LACIE-00430 (REVA)

JSC-11343

LARGE AREA CROP INVENTORY EXPERIMENT (LACIE) CROP INVENTORY

0U 0 Nm

tn

I- NASA NOAA USDA 4

WHEATYIELD -MODELSEq FOR THE

= USSR

t~~AUGl 1977 RECEIVED

~NASA

SN)

STI FACILIW CINPUT BRANCH

NationalAeronautics and Space Administration

LYNDON B JOHNSON SPACE CENTER Houston Texas

JUNE 1977

httpsntrsnasagovsearchjspR=19770023630 2018-05-21T144235+0000Z

DOCUMENT

PREPARED BY

NOAA PERSONNEL

CENTER FOR CLIMATIC AND ENVIRONMENTAL ASSESSMENT

COLUMBIA MISSOURI

TECHNICAL NOTE 77-2

YIELD MODELS FOR THE USSR

MAY 1977

Authorized by for Norton D Strommen

Director CCEA June 10 1977

ACKNOWLEDGMENT

The authors are pleased to recognize the supporting staff

at the Center for Climatic and Environmental Assessment for their

assistance in the completion of this project and report Rita Fobian

Rita Terry Jeanne Beare Nancy Beever and Paula Rosenkoetter were

helpful in data analysis drafting typing and editing of the work

contained herein It would have been difficult to complete this

study in the allocated time without them

iii

WHEAT YIELD ESTIMATION MODELS

FOR THE USSR

Clarence M Sakamoto and Sharon K LeDuc

Introduction

The Union of Soviet Socialist Republics (USSR) is the leading

wheat-pioducer in the world However USSR production has been highly

variable primarily because of weather conditions Much of the USSR

wheat is grown under extreme climatic conditions

This study reports on a quantitative model determining the

relationship between weather conditions and wheat yield in the USSR

The purpose of the model is to provide reliable forecasts on the size

of the USSR wheat harvest earlier than do currently available reports

Since wheat is grown in many areas of the USSR under diverse

climatic and cultural conditions separate models were developed for

different geographic locations- The basic geographic-area represented

by a model was a crop region Because of data limitations occasionally

two or more crop regions were combined

Separate models are developed for spring-wheat and for winter shy

the two major wheat classes in the USSR -Differences in yield potential

and responses to stress conditions and cultural improvements necessitate

models for each class

1

2

The basic yield data were obtained from various sources for the

period 1958-1973 (CIA Personal Communication Manellya et al 1972

Economic Research Service USDA Personal Communication) A problem of

unknown scope with USSR statistics is the practice of reporting grain

yields and production in bunker weight - the weight of the grain as it

comes from the combine (Pope et al 1973) That is the data represent

grain containing varying amounts of moisture and foreign matter depending

on weather conditions during harvest Hence some annual variation would

be expected if bunker weight were converted to a standard measure

representing usable grain

The USSR was divided into 33 regions Most of these include

more than one Oblast (Figure 1) Production and acreage information were

available for each Oblast The yield for a region was calculated by

dividing the total production by the total acreage in each region In

some cases only yield data not acreage and production were available

for the latter years particularly for 1972 and 1973 Wheat yield data

for the period 1947-1969 are published (Manellya et al 1972) for

parts of the USSR but corresponding climatic data are not readily

available

The climatological data base 1961-1973 was developed by ETACQ

the Environmental Technical Application Branch of the Air Force For the

period 1961-1965 the meteorological data were extracted by hand from

weather maps The data bases contain the unweighted average of the

observations within a region Since it was desirable to increase the

sample size the data base for the period 1957 through 1961 was estimated

with the use of World Meteorological Organization (WMO) climatological

3

USS R

-- b

00 1412

9 is 20 22

70 it 0-- 26 21 22- I

ie Crprgonscsowigaesoywchhatmdl1 hveen

4

Figure 1 Crop regions showing areas fo r which wheat models have been

developed The hatched-lines within a darkened line area show the inclusion

of more than one crop region in a single model

4

records (USDC ESSA 1966 1967) The data were plotted by computer

and analyzed subjectively for each region through the precipitation

isohyets and temperature isotherms for each month of th years covered

Factors Affecting Wheat Production

The USSR produces approximately one-fourth of the total

world wheat (Bureau of Agricultural Economics 1974) Winter wheat is

grown primarily in European USSR while spring wheat is the principal

wheat grown in Asiatic USSR Production of all wheat increased

40 percent from 1959-1964 to 1969-1973 However planted acreage and

harvested acreage has changed little since 1955 (Figure 2) The increased

production is therefore due to an upward trend in yield (Manellya

et al 1972) Approximately 75 percent of the total wheat-sown area

is planted to spring wheat the remainder to winter wheat Figure 2

shows the total area sown to each during the period 1950 through 1973

During those years where winterkill was substantial eg 1960 1969

replanting to spring wheat was evident The variation in harvested

acreage has been associated with the variability in weather (eg 1960

1969 1972) Winterkill and moisture stress are two major weather

hazards that reduce wheat production in the Soviet Union

Since 1949 both spring and winter wheat have shown an upward

yield trend (Figures 3 and 4) Factors contributing to higher yield

include improved varieties increased mechanization greater fertilizer

use irrigation of more acres application of pesticides on more hectares

etc

The bulk of the Russian wheat is harvested from June through

August Winter wheat is usually harvested earlier than spring wheat

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

DOCUMENT

PREPARED BY

NOAA PERSONNEL

CENTER FOR CLIMATIC AND ENVIRONMENTAL ASSESSMENT

COLUMBIA MISSOURI

TECHNICAL NOTE 77-2

YIELD MODELS FOR THE USSR

MAY 1977

Authorized by for Norton D Strommen

Director CCEA June 10 1977

ACKNOWLEDGMENT

The authors are pleased to recognize the supporting staff

at the Center for Climatic and Environmental Assessment for their

assistance in the completion of this project and report Rita Fobian

Rita Terry Jeanne Beare Nancy Beever and Paula Rosenkoetter were

helpful in data analysis drafting typing and editing of the work

contained herein It would have been difficult to complete this

study in the allocated time without them

iii

WHEAT YIELD ESTIMATION MODELS

FOR THE USSR

Clarence M Sakamoto and Sharon K LeDuc

Introduction

The Union of Soviet Socialist Republics (USSR) is the leading

wheat-pioducer in the world However USSR production has been highly

variable primarily because of weather conditions Much of the USSR

wheat is grown under extreme climatic conditions

This study reports on a quantitative model determining the

relationship between weather conditions and wheat yield in the USSR

The purpose of the model is to provide reliable forecasts on the size

of the USSR wheat harvest earlier than do currently available reports

Since wheat is grown in many areas of the USSR under diverse

climatic and cultural conditions separate models were developed for

different geographic locations- The basic geographic-area represented

by a model was a crop region Because of data limitations occasionally

two or more crop regions were combined

Separate models are developed for spring-wheat and for winter shy

the two major wheat classes in the USSR -Differences in yield potential

and responses to stress conditions and cultural improvements necessitate

models for each class

1

2

The basic yield data were obtained from various sources for the

period 1958-1973 (CIA Personal Communication Manellya et al 1972

Economic Research Service USDA Personal Communication) A problem of

unknown scope with USSR statistics is the practice of reporting grain

yields and production in bunker weight - the weight of the grain as it

comes from the combine (Pope et al 1973) That is the data represent

grain containing varying amounts of moisture and foreign matter depending

on weather conditions during harvest Hence some annual variation would

be expected if bunker weight were converted to a standard measure

representing usable grain

The USSR was divided into 33 regions Most of these include

more than one Oblast (Figure 1) Production and acreage information were

available for each Oblast The yield for a region was calculated by

dividing the total production by the total acreage in each region In

some cases only yield data not acreage and production were available

for the latter years particularly for 1972 and 1973 Wheat yield data

for the period 1947-1969 are published (Manellya et al 1972) for

parts of the USSR but corresponding climatic data are not readily

available

The climatological data base 1961-1973 was developed by ETACQ

the Environmental Technical Application Branch of the Air Force For the

period 1961-1965 the meteorological data were extracted by hand from

weather maps The data bases contain the unweighted average of the

observations within a region Since it was desirable to increase the

sample size the data base for the period 1957 through 1961 was estimated

with the use of World Meteorological Organization (WMO) climatological

3

USS R

-- b

00 1412

9 is 20 22

70 it 0-- 26 21 22- I

ie Crprgonscsowigaesoywchhatmdl1 hveen

4

Figure 1 Crop regions showing areas fo r which wheat models have been

developed The hatched-lines within a darkened line area show the inclusion

of more than one crop region in a single model

4

records (USDC ESSA 1966 1967) The data were plotted by computer

and analyzed subjectively for each region through the precipitation

isohyets and temperature isotherms for each month of th years covered

Factors Affecting Wheat Production

The USSR produces approximately one-fourth of the total

world wheat (Bureau of Agricultural Economics 1974) Winter wheat is

grown primarily in European USSR while spring wheat is the principal

wheat grown in Asiatic USSR Production of all wheat increased

40 percent from 1959-1964 to 1969-1973 However planted acreage and

harvested acreage has changed little since 1955 (Figure 2) The increased

production is therefore due to an upward trend in yield (Manellya

et al 1972) Approximately 75 percent of the total wheat-sown area

is planted to spring wheat the remainder to winter wheat Figure 2

shows the total area sown to each during the period 1950 through 1973

During those years where winterkill was substantial eg 1960 1969

replanting to spring wheat was evident The variation in harvested

acreage has been associated with the variability in weather (eg 1960

1969 1972) Winterkill and moisture stress are two major weather

hazards that reduce wheat production in the Soviet Union

Since 1949 both spring and winter wheat have shown an upward

yield trend (Figures 3 and 4) Factors contributing to higher yield

include improved varieties increased mechanization greater fertilizer

use irrigation of more acres application of pesticides on more hectares

etc

The bulk of the Russian wheat is harvested from June through

August Winter wheat is usually harvested earlier than spring wheat

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

ACKNOWLEDGMENT

The authors are pleased to recognize the supporting staff

at the Center for Climatic and Environmental Assessment for their

assistance in the completion of this project and report Rita Fobian

Rita Terry Jeanne Beare Nancy Beever and Paula Rosenkoetter were

helpful in data analysis drafting typing and editing of the work

contained herein It would have been difficult to complete this

study in the allocated time without them

iii

WHEAT YIELD ESTIMATION MODELS

FOR THE USSR

Clarence M Sakamoto and Sharon K LeDuc

Introduction

The Union of Soviet Socialist Republics (USSR) is the leading

wheat-pioducer in the world However USSR production has been highly

variable primarily because of weather conditions Much of the USSR

wheat is grown under extreme climatic conditions

This study reports on a quantitative model determining the

relationship between weather conditions and wheat yield in the USSR

The purpose of the model is to provide reliable forecasts on the size

of the USSR wheat harvest earlier than do currently available reports

Since wheat is grown in many areas of the USSR under diverse

climatic and cultural conditions separate models were developed for

different geographic locations- The basic geographic-area represented

by a model was a crop region Because of data limitations occasionally

two or more crop regions were combined

Separate models are developed for spring-wheat and for winter shy

the two major wheat classes in the USSR -Differences in yield potential

and responses to stress conditions and cultural improvements necessitate

models for each class

1

2

The basic yield data were obtained from various sources for the

period 1958-1973 (CIA Personal Communication Manellya et al 1972

Economic Research Service USDA Personal Communication) A problem of

unknown scope with USSR statistics is the practice of reporting grain

yields and production in bunker weight - the weight of the grain as it

comes from the combine (Pope et al 1973) That is the data represent

grain containing varying amounts of moisture and foreign matter depending

on weather conditions during harvest Hence some annual variation would

be expected if bunker weight were converted to a standard measure

representing usable grain

The USSR was divided into 33 regions Most of these include

more than one Oblast (Figure 1) Production and acreage information were

available for each Oblast The yield for a region was calculated by

dividing the total production by the total acreage in each region In

some cases only yield data not acreage and production were available

for the latter years particularly for 1972 and 1973 Wheat yield data

for the period 1947-1969 are published (Manellya et al 1972) for

parts of the USSR but corresponding climatic data are not readily

available

The climatological data base 1961-1973 was developed by ETACQ

the Environmental Technical Application Branch of the Air Force For the

period 1961-1965 the meteorological data were extracted by hand from

weather maps The data bases contain the unweighted average of the

observations within a region Since it was desirable to increase the

sample size the data base for the period 1957 through 1961 was estimated

with the use of World Meteorological Organization (WMO) climatological

3

USS R

-- b

00 1412

9 is 20 22

70 it 0-- 26 21 22- I

ie Crprgonscsowigaesoywchhatmdl1 hveen

4

Figure 1 Crop regions showing areas fo r which wheat models have been

developed The hatched-lines within a darkened line area show the inclusion

of more than one crop region in a single model

4

records (USDC ESSA 1966 1967) The data were plotted by computer

and analyzed subjectively for each region through the precipitation

isohyets and temperature isotherms for each month of th years covered

Factors Affecting Wheat Production

The USSR produces approximately one-fourth of the total

world wheat (Bureau of Agricultural Economics 1974) Winter wheat is

grown primarily in European USSR while spring wheat is the principal

wheat grown in Asiatic USSR Production of all wheat increased

40 percent from 1959-1964 to 1969-1973 However planted acreage and

harvested acreage has changed little since 1955 (Figure 2) The increased

production is therefore due to an upward trend in yield (Manellya

et al 1972) Approximately 75 percent of the total wheat-sown area

is planted to spring wheat the remainder to winter wheat Figure 2

shows the total area sown to each during the period 1950 through 1973

During those years where winterkill was substantial eg 1960 1969

replanting to spring wheat was evident The variation in harvested

acreage has been associated with the variability in weather (eg 1960

1969 1972) Winterkill and moisture stress are two major weather

hazards that reduce wheat production in the Soviet Union

Since 1949 both spring and winter wheat have shown an upward

yield trend (Figures 3 and 4) Factors contributing to higher yield

include improved varieties increased mechanization greater fertilizer

use irrigation of more acres application of pesticides on more hectares

etc

The bulk of the Russian wheat is harvested from June through

August Winter wheat is usually harvested earlier than spring wheat

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

WHEAT YIELD ESTIMATION MODELS

FOR THE USSR

Clarence M Sakamoto and Sharon K LeDuc

Introduction

The Union of Soviet Socialist Republics (USSR) is the leading

wheat-pioducer in the world However USSR production has been highly

variable primarily because of weather conditions Much of the USSR

wheat is grown under extreme climatic conditions

This study reports on a quantitative model determining the

relationship between weather conditions and wheat yield in the USSR

The purpose of the model is to provide reliable forecasts on the size

of the USSR wheat harvest earlier than do currently available reports

Since wheat is grown in many areas of the USSR under diverse

climatic and cultural conditions separate models were developed for

different geographic locations- The basic geographic-area represented

by a model was a crop region Because of data limitations occasionally

two or more crop regions were combined

Separate models are developed for spring-wheat and for winter shy

the two major wheat classes in the USSR -Differences in yield potential

and responses to stress conditions and cultural improvements necessitate

models for each class

1

2

The basic yield data were obtained from various sources for the

period 1958-1973 (CIA Personal Communication Manellya et al 1972

Economic Research Service USDA Personal Communication) A problem of

unknown scope with USSR statistics is the practice of reporting grain

yields and production in bunker weight - the weight of the grain as it

comes from the combine (Pope et al 1973) That is the data represent

grain containing varying amounts of moisture and foreign matter depending

on weather conditions during harvest Hence some annual variation would

be expected if bunker weight were converted to a standard measure

representing usable grain

The USSR was divided into 33 regions Most of these include

more than one Oblast (Figure 1) Production and acreage information were

available for each Oblast The yield for a region was calculated by

dividing the total production by the total acreage in each region In

some cases only yield data not acreage and production were available

for the latter years particularly for 1972 and 1973 Wheat yield data

for the period 1947-1969 are published (Manellya et al 1972) for

parts of the USSR but corresponding climatic data are not readily

available

The climatological data base 1961-1973 was developed by ETACQ

the Environmental Technical Application Branch of the Air Force For the

period 1961-1965 the meteorological data were extracted by hand from

weather maps The data bases contain the unweighted average of the

observations within a region Since it was desirable to increase the

sample size the data base for the period 1957 through 1961 was estimated

with the use of World Meteorological Organization (WMO) climatological

3

USS R

-- b

00 1412

9 is 20 22

70 it 0-- 26 21 22- I

ie Crprgonscsowigaesoywchhatmdl1 hveen

4

Figure 1 Crop regions showing areas fo r which wheat models have been

developed The hatched-lines within a darkened line area show the inclusion

of more than one crop region in a single model

4

records (USDC ESSA 1966 1967) The data were plotted by computer

and analyzed subjectively for each region through the precipitation

isohyets and temperature isotherms for each month of th years covered

Factors Affecting Wheat Production

The USSR produces approximately one-fourth of the total

world wheat (Bureau of Agricultural Economics 1974) Winter wheat is

grown primarily in European USSR while spring wheat is the principal

wheat grown in Asiatic USSR Production of all wheat increased

40 percent from 1959-1964 to 1969-1973 However planted acreage and

harvested acreage has changed little since 1955 (Figure 2) The increased

production is therefore due to an upward trend in yield (Manellya

et al 1972) Approximately 75 percent of the total wheat-sown area

is planted to spring wheat the remainder to winter wheat Figure 2

shows the total area sown to each during the period 1950 through 1973

During those years where winterkill was substantial eg 1960 1969

replanting to spring wheat was evident The variation in harvested

acreage has been associated with the variability in weather (eg 1960

1969 1972) Winterkill and moisture stress are two major weather

hazards that reduce wheat production in the Soviet Union

Since 1949 both spring and winter wheat have shown an upward

yield trend (Figures 3 and 4) Factors contributing to higher yield

include improved varieties increased mechanization greater fertilizer

use irrigation of more acres application of pesticides on more hectares

etc

The bulk of the Russian wheat is harvested from June through

August Winter wheat is usually harvested earlier than spring wheat

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

2

The basic yield data were obtained from various sources for the

period 1958-1973 (CIA Personal Communication Manellya et al 1972

Economic Research Service USDA Personal Communication) A problem of

unknown scope with USSR statistics is the practice of reporting grain

yields and production in bunker weight - the weight of the grain as it

comes from the combine (Pope et al 1973) That is the data represent

grain containing varying amounts of moisture and foreign matter depending

on weather conditions during harvest Hence some annual variation would

be expected if bunker weight were converted to a standard measure

representing usable grain

The USSR was divided into 33 regions Most of these include

more than one Oblast (Figure 1) Production and acreage information were

available for each Oblast The yield for a region was calculated by

dividing the total production by the total acreage in each region In

some cases only yield data not acreage and production were available

for the latter years particularly for 1972 and 1973 Wheat yield data

for the period 1947-1969 are published (Manellya et al 1972) for

parts of the USSR but corresponding climatic data are not readily

available

The climatological data base 1961-1973 was developed by ETACQ

the Environmental Technical Application Branch of the Air Force For the

period 1961-1965 the meteorological data were extracted by hand from

weather maps The data bases contain the unweighted average of the

observations within a region Since it was desirable to increase the

sample size the data base for the period 1957 through 1961 was estimated

with the use of World Meteorological Organization (WMO) climatological

3

USS R

-- b

00 1412

9 is 20 22

70 it 0-- 26 21 22- I

ie Crprgonscsowigaesoywchhatmdl1 hveen

4

Figure 1 Crop regions showing areas fo r which wheat models have been

developed The hatched-lines within a darkened line area show the inclusion

of more than one crop region in a single model

4

records (USDC ESSA 1966 1967) The data were plotted by computer

and analyzed subjectively for each region through the precipitation

isohyets and temperature isotherms for each month of th years covered

Factors Affecting Wheat Production

The USSR produces approximately one-fourth of the total

world wheat (Bureau of Agricultural Economics 1974) Winter wheat is

grown primarily in European USSR while spring wheat is the principal

wheat grown in Asiatic USSR Production of all wheat increased

40 percent from 1959-1964 to 1969-1973 However planted acreage and

harvested acreage has changed little since 1955 (Figure 2) The increased

production is therefore due to an upward trend in yield (Manellya

et al 1972) Approximately 75 percent of the total wheat-sown area

is planted to spring wheat the remainder to winter wheat Figure 2

shows the total area sown to each during the period 1950 through 1973

During those years where winterkill was substantial eg 1960 1969

replanting to spring wheat was evident The variation in harvested

acreage has been associated with the variability in weather (eg 1960

1969 1972) Winterkill and moisture stress are two major weather

hazards that reduce wheat production in the Soviet Union

Since 1949 both spring and winter wheat have shown an upward

yield trend (Figures 3 and 4) Factors contributing to higher yield

include improved varieties increased mechanization greater fertilizer

use irrigation of more acres application of pesticides on more hectares

etc

The bulk of the Russian wheat is harvested from June through

August Winter wheat is usually harvested earlier than spring wheat

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

3

USS R

-- b

00 1412

9 is 20 22

70 it 0-- 26 21 22- I

ie Crprgonscsowigaesoywchhatmdl1 hveen

4

Figure 1 Crop regions showing areas fo r which wheat models have been

developed The hatched-lines within a darkened line area show the inclusion

of more than one crop region in a single model

4

records (USDC ESSA 1966 1967) The data were plotted by computer

and analyzed subjectively for each region through the precipitation

isohyets and temperature isotherms for each month of th years covered

Factors Affecting Wheat Production

The USSR produces approximately one-fourth of the total

world wheat (Bureau of Agricultural Economics 1974) Winter wheat is

grown primarily in European USSR while spring wheat is the principal

wheat grown in Asiatic USSR Production of all wheat increased

40 percent from 1959-1964 to 1969-1973 However planted acreage and

harvested acreage has changed little since 1955 (Figure 2) The increased

production is therefore due to an upward trend in yield (Manellya

et al 1972) Approximately 75 percent of the total wheat-sown area

is planted to spring wheat the remainder to winter wheat Figure 2

shows the total area sown to each during the period 1950 through 1973

During those years where winterkill was substantial eg 1960 1969

replanting to spring wheat was evident The variation in harvested

acreage has been associated with the variability in weather (eg 1960

1969 1972) Winterkill and moisture stress are two major weather

hazards that reduce wheat production in the Soviet Union

Since 1949 both spring and winter wheat have shown an upward

yield trend (Figures 3 and 4) Factors contributing to higher yield

include improved varieties increased mechanization greater fertilizer

use irrigation of more acres application of pesticides on more hectares

etc

The bulk of the Russian wheat is harvested from June through

August Winter wheat is usually harvested earlier than spring wheat

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

4

records (USDC ESSA 1966 1967) The data were plotted by computer

and analyzed subjectively for each region through the precipitation

isohyets and temperature isotherms for each month of th years covered

Factors Affecting Wheat Production

The USSR produces approximately one-fourth of the total

world wheat (Bureau of Agricultural Economics 1974) Winter wheat is

grown primarily in European USSR while spring wheat is the principal

wheat grown in Asiatic USSR Production of all wheat increased

40 percent from 1959-1964 to 1969-1973 However planted acreage and

harvested acreage has changed little since 1955 (Figure 2) The increased

production is therefore due to an upward trend in yield (Manellya

et al 1972) Approximately 75 percent of the total wheat-sown area

is planted to spring wheat the remainder to winter wheat Figure 2

shows the total area sown to each during the period 1950 through 1973

During those years where winterkill was substantial eg 1960 1969

replanting to spring wheat was evident The variation in harvested

acreage has been associated with the variability in weather (eg 1960

1969 1972) Winterkill and moisture stress are two major weather

hazards that reduce wheat production in the Soviet Union

Since 1949 both spring and winter wheat have shown an upward

yield trend (Figures 3 and 4) Factors contributing to higher yield

include improved varieties increased mechanization greater fertilizer

use irrigation of more acres application of pesticides on more hectares

etc

The bulk of the Russian wheat is harvested from June through

August Winter wheat is usually harvested earlier than spring wheat

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

USSR

5

WHEAT

PRODUCTION

~Total

100

1-4

80

so

60

02

1950 55 60 65 70 73

-AREA SOWN

20 0

950 0190 5-5 60 65 0 73

Eigure 2 March of production and spring and winter wheat sown area in the USSR from 1950-1973 (source CIA 1974)

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

15

6

RSFSR SPRING WHEAT YIELDS

i II Iiii

dii10

5shy

0

1948 1952 1956 1960 1964 1968

Year

Figure 3 Spring wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya at al 1972)

1972

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

7

RSFSR WINTER WHEAT YIELDS

25

20

IC

U

15

5

1964 19681948 1952 1956 1960

Year

Figure 4 Winter wheat yield in the Russian Soviet Federated Socialist Republic (RSFSR) 1949-1972 (data Manellya et al 1972)

1972

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

8

The wheat-growing area in the USSR covers a wide range of

climate The distance between the northern and southern latitudes spans

over a thousand miles Other features such as mountains and distance

from oceans vary widely Consequently each region has unique perennial

weather-related problems that affect wheat yield For example regions

close to the Black Sea 6 7 and 9 are influenced by the moderating

effect of the waters which can lead to wheat rust problems In

Regions 13 and 14 excessive moisture during spring is a major concern

In Kazakhstan and regions north and east of the Caspian Sea drought

and sukhovei (a hot dry wind) onset are perennial yield reducing

problems East of the Ural Mountains in Regions 20 26 and 27 excessive

spring rains affect planting and fall frosts affect the ripening of grain

The time of moisture stress relative to the growth stage

affects the degree of yield reduction If moisture stress is experienced

at the heading through flowering phase and the filling phase yield is

reduced substantially Yield is also reduced when stress occurs during

earlier growth stages but reduction is not as great as when stress

occurs during the heading period (Bauer 1972 Panomarev 1962)

High temperature can also be detrimental to wheat production

Temperatures above 32C (90F) can hurt wheat crop yield during critical

periods such as flowering (Jensen and Lund 1971 Kogan 1966 Panomarev

-1962) Low temperatures affect the wheat plant differently depending on

the growth stage and variety Areas with a continental climate

particularly in European USSR have the highest probability of low

temperature damage A combination of poor snow cover low humidity

and strong winds can cause extensive damage For example as much as

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

9

35 percent of the fall-sown winter grains was estimated to have been

winterkilled in 1969 (CIA 1974) The Soviets have suggested that snow

-cover should be at-least 30 cmlin European USSR and 40 cm in Asiatic

USSR to provide protection from the temperature hazards of winter

(CIA 1974) Winter wheat can withstand a temperature of -400C (-400 F)

if the crop is hardened prior to the low temperature and protected by

the snow cover Without a snow cover the same crop could withstand

temperatures as low as -320C (-250F) (Martin and Leonard 1949) Martin

and Leonard also indicate that spring wheat can withstand temperatures as

low as -90c (150F) However temperatures a degree or two-below freezing

during the period from heading through grain development can reduce yield

substantially The extent to which yield is affected depends upon the

duration of the low temperature as well as the variety of wheat

A phenomenon which can also reduce wheat yield in a short

period of time from a few hours to a few days is the sukhovei - hot dry

winds that occur most frequently in the southern and southeastern sections

of European USSR in Kazakhstan east of the Volga and in Western

Siberia On a sukhovei day the relative humidity-frequently drops below

30 percent evapotranspiration increases to a point where the plant even

wilts although moisture is present in the soil The relative humidity

at night during a sukhovei is sometimes lower than during a drought (Borisov

1959) The frequency of the sukhovei resembles a drought frequency chart

in scope as well as in percentage (Figure 5 after Alpatev in Vitkevich 1960)

Most of the precipitation in the USSR falls during the months

of April through September (Figure 6) In the northern Belorussia and

Central Regions the maximum occurs late in July and August which hampers

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

10

32 40 4 56 64

6 =C

60

ouht DFigre req eny Cartin heUSSR (o uretik vc16)

FF 4 te so

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

9O 40 t0 0 100 IKO 140 toO I0

5 o r~mo c50-ro

rit

of pecipiationin th pimto mlmth ApilSDistrbutio warm of yer e

Figure 6 Average precipitation during the warm period April through September

(source10orisov1959)

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

12

harvesting operations Also in these areas low temperatures and frost

can reduce yield substantially (Jakovlev 1973)

Although rainfall during a critical period is beneficial

excessive rainfall can have a depressing effect on yield Bogdanov (1965)

for example found that for spring wheat excessive rainfall from the

period following flowering-to waxy ripe or hard dough stage reduced yield

in the central non-Chernozem region In this report these areas include

Regions 11 and 12 of Figure 1 Jakovlev (1973) also reported that in

northern Kazakhstan high yields were characterized by above normal

May-July rainfall (1757185 mm) with temperatures below 200C in July

Winter wheat productivity is affected not only by spring and

summer weather but also by precipitation during the preceding fall and

winter which adds to the soil moisture reserve and supplements the

spring and summer rainfall If the soil moisture reserve is low and May

precipitation is less than12 mm in the Steppe Regions of Ukraine and

Northern Caucasus winter wheat yield will be low (Ulanova 1966) Yields

may also be lowered if May precipitation is excessive (more than 80 mm)

However if soil moisture reserve is low high yields are possible if May

precipitation is high

The Regression Models

A mathematical model was developed for each_region regressing

wheat yield against a time variable as a surrogate for factors affecting

yield trend and a set of weather variables measuring the influence of

weather The basic general model for a particularregion which may include

several subregions is n

Y =a + OT + EkWik ii h k=lr - i

where

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

13

i = year

j = subregion j 1 2 m and m differs with models

k = weather variable k = 1 n and n differs with models

Yj estimated yield for the ith year and jth subregion

aj = donstant for the Jth subregion

=coefficient for trend T

T= trend for ith year (1958=1 1959=2 1973=16)

Yjk = coefficient for kth weather variable Wijk where

These are the aridity index temperature anomaly andor

precipitation anomaly or the square of one of these variables

(these weather variables are based on monthly data only) The

kth weather variable is not the same function for each model

n = the number of distinct weather variables and will vary by region

Eij = unexplained variation of the ith year and jth subregion

In most cases a linear trend is included in the model but where

a time variable failed to improve the predictive equation the coefficient

a was then assumed to be zero

The Weather Variables

The basic weather data consisting of monthly temperature and

monthly precipitation are used to derive monthly weather variables

consisting of an aridity indexi- a monthly temperature departure from

normal and a monthly precipitation departure from normal The aridity

index also expressed as the departure from normal where normal is the

average value (usually 1958-1973) is defined as monthly precipitation minus

potential evapotranspiration (PET) Thornthwaites procedure (Palmer

and Havens 1958 Thornthwaite 1948) for estimating potential evapotransshy

piration is utilized The formula for PET is

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

14

160 10 (T)mIlaPET =

where PET = monthly potential evapotranspiration in millimeters for

the month m

(T)m = monthly mean temperature ( C) for month m 12

=I heat index = E hm mn=l

and hm = 1514

for m7i (January)through m712 (December)

-a = 675 x 10-7I 3 - 771 x 10-5I 2 + 179 x 10 2 + 049

Expressions for a and h were determined empirically by Thornthwaite (1948)

I is a heat index which is a constant for a given location Daylight

corrections are applied as a fraction of 12 hours

In some cases the departure of the observed precipitation Pm

from the average precipitation Pm was used in lieu of the aridity index

In most cases the first weather variable to enter the model is typically

the accumulated preseason moisture generally from September through

March of the growing season

The monthly temperature departure from normal is defined as

T - T where T is the observed temperature and T is the averagem m - m _

temperature over the data period for month m The data period was

generally 1958-1973

Estimates of wneat yield are desired as early in the season as

possible Hence truncated models were developed using as much weather

data as is available at the truncated period For example a truncated

winter wheat model for March used weather coefficients through the month

of March

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

15

Selection of Weather Variables

In selecting the final model for a region the four basic

guidelines used were

1 The coefficient signs are agronomically feasible

2 The standard error is reduced with each truncation

3 The variable selected in the initial truncation is maintained

for subsequent truncation

4 The final model explains as much of the yield variability

as possible

The selection of weather variables usually began with determining

a preseason variable such as total precipitation from September through

April (preseason moisture) for spring wheat The months included for

preseason moisture varied with regions (eg September through March

or November through March) In some areas such as the Kazakhstan regions

preseason accumulated precipitation failed to show any statistical

importance This is probably-due to the relative dryness of the arid and

semi-arid zone where rainfall prior to planting has evaporated and is not

available in the subsoil for later use

In the winter wheat areaswinter temperatures are important to

the winterkill problem This leads to the problem of determining what

constitutes -thewinter months For example in those regions in-the

European USSR near the Bl ackSea--the winter-months include January

and February for the assessment of winter temperature Farther to the

interior of the USSR these months include November or December through

March Different months were tested to determine the best fit of a winter

temperature variable to yield

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

16

The aridity index value precipitation minus PET which

combines both temperature and precipitation was generally tried first

for the spring months In some cases where this aridity index failed to

show its significance precipitation was included for analysis The

inclusion of only precipitation for the spring and summer months indicates

that this variable was abetter indicator of yield response than the

aridity index

April temperature was often important in wheat growing areas

Generally speaking higher temperature is associated with the enhancement

of regrowth of the winter wheat and the establishment of spring wheat

Where the spring temperature shows a negative coefficient (eg Region

13) this can be interpreted-to mean that too early a warming period

during April will enhance vegetative growth at the expense of grain

development in winter wheat

In some cases the introduction of a vaiiable increased the standard

error of estimate slightly but this variable was maintained if it was

determined to be agronomically reasonable and the addition of another

variable for the subsequent truncation period increased the fit of the

data to the model This would not have occurred if the variable in the

previous truncation period had been removed

The description of each model is included in the Appendix A

list of all models for specified regions is also attached The darkened

outline for an area indicates a particular model which may include

more than one region If more than one region is included in a model

this is noted by hatched lines (see Figure 1)

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

17

-Summary

The models for the USSR have been developed with limited

meteorological and yield data

It is suggested that those using these models apply a flagging

system to detect extreme temperatures andor precipitation A suggested

flagging system might include flagging precipitation values greater than

the 90th percentile andor less than the 10th percentile temperature

values greater than the 95th percentile andor less than the-5th

percentile might also be flagged In these instances the value for the

10th or 90th percentile for precipitation or the 5th or 95th

percentile for temperaturemight be used in lieu of the extreme value

Furthermore it is suggested that yield results less than zero be

assumed to be zero

Additional years should help to stabilize the coefficients

involved in the equation The extension of the time trend three years

into the future is dangerous because of the size of the coefficient and

the potential instability

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

REFERENCES

Australia Bureau of Agricultural Economics 1974 Wheat Situation

and Outlook Canberra

Bauer A 1972 Effect of Water Supply and Seasonal Distribution on

Spring Wheat Yields Bulletin 490 North Dakota Agricultural

Experiment Station Fargo

Bogdanov T F 1965 The Dependence of the Spring Wheat Yield on the

Amount of Precipitation in the Central Non-Chernozem Zojie

Meteorologiya i Gidrologiya 746-48 (in Russian)

Borisov A A 1959 Climates of the USSR ed by G A Halstead

trans by R A Ledward Chicago Aldine

Central Intelligence Agency 1974 USSR Agriculture Atlas

Washington December

Jakovlev N N 1973 Agrometeorological Factors Influencing Spring

Wheat Yield and Grain Quality in the Soviet Socialist Republics

Plant Response to Climatic Factors Proceedings of the Uppsala

Symposium ed by R 0 Slayter Paris UNESCO

Jensen 1 A and H R Lund 1971 How Cereal Crops Grow

Extension Bulletin Number 3 North Dakota State University Fargo

Kogan F N 1966 Estimate of the Summer Wheat Yield by Meteorological

Data in Regions with a Clearly Continental Climate Meteorologiya

i Gidrologiya 10 14-18 (in Russian)

Manellya A I N N Nagnibelova A A Frenkel and L I Vashchukov

1972 Dinamika Urozhaynosti Selskokhozyaystvennykh Kultur v RSFSR

(Dynamics of Agricultural Crop Yields in the RSFSR) Moscow

Statistika

18

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

19

Martin J F and W H Leonard 1949 Principles of Field Crop

Production New York McMillan

Palmer W C and A V Havens 1958 A Graphical Technique for

Determining Fvapotranspiration by the Thornthwaite Method

Monthly Weather Review

Panomarev B P 1962 An Appraisal of Agro-Meteorological Conditions

of Spring Wheat Production in the Steppe and Forest-Steppe

Zones of the RFSFR Transactions Tsentr Institute Prognozov

1013-24 (in Russian)

Pope Fletcher Jr V Zabijaka and W Ragsdale 1973 Agriculture

in the United States and the Soviet Union FAS Report Number 92

Washington US Department of Agriculture Economic Research Service

Thornthwaite C W 1948 An Approach Toward a Pational Classification of

Climate Geographical Review 3855-94

Ulanova E S 1966 The Effect of May Precipitation on Yields of Tinter

Wheatin the Steppe Regions of the Ukraine and Northern Caucasus

Meteorologiya i Gidrologiya 517-25

US Department of Commerce Environmental Science Services Administration

1966 World Weather Records Vol 2 Europe Washington

US Department of Commerce Environmental Science Services Administration

1967 World Weather Records Vol 4 Asia Washington

Vitkevich V 1 1960 Agricultural Meteorology Jerusalem Israel

Program for Scientific Translation

APPENDIX

USSR WINTER WHEAT MODELS

TranscaucasusBaltics-Belorussia

1 Baltics 2 Belorussia

North Ukraine

3 West Ukraine 4 North Central Ukraine 5 Northeast Ukraine

Ukraine-Krasnodar

6 Eastern Ukraine 7 Southern Ukraine 9 Krasnodar

Moldavia

8 Moldavia

Caucasus-Volga

10 Northeast Caucasus 17 Lower Volga

Black Soil Zone

11 West Black Soil Zone 12 East Black Soil Zone

Central District

13 Central Region

Volga-Vyatsk

14 Volga-Vyatsk

Upper Volga

15 Upper Volga

Middle Volga

16 Middle Volga

Northwest Urals

18 Northwest Urals

A-1

28 Transcaucasus

South Kazakhstan

29 South Kazakhstan

Central Asia

30 Central Asia

Northwest

33 Northwest

APPENDIX

USSR SPRING WHEAT MODELS

Black Soil Zone South Kazakhstan

11 WestBlack Soil Zone 29 South Kazakhstan 12 East Black Soil Zone

Central Asia Central District

30 Central Asia 13 Central Region

Eastern Siberia Volga-Vyatsk 31 Eastern Siberia

14 Volga-Vyatsk

Far East Upper Volga

32 Far East

15 Upper Volga Northwest

Middle Volga 33 Northwest

16 Middle Volga

Caucasus-Volga

10 Northeast Caucasus 17 Lower Volga

Northwest Urals

18 Northwestern Urals

Southern Urals-Western Kazakhstan

19 Southern Urals 21 Western Kazakhstan

Northeastern Urals

20 Northeastern Urals

Northeast Kazakh

22 Kustanay 23 Tselinograd 24 Northern Kazakhstan 25 Pavlodar

Siberia-Altai

26 Western Siberia 27 Altai Krai

A-2

BALTICS-BELORUSSIA WINTER WHEAT COVARIANCE MODEL

Region

Baltics - Crop Region I

Belorussia - Crop Region 2

PET A = 946 April Daylength = 11674 Latitude = 55degN PET I = 27816 May Daylength = 13374

June Daylength = 14254

Crop Region 1 Constant = 1 if Data from Crop Region 1 Otherwise 0

Variable Deviation Normal Trend March April May June

Overall Constant 100 433592 456263 488144 482387 479744 Region 1 Constant 100 281226 234473 220686 237189 242756 Linear Trend (1958-1973) 1600 110882 110965 108025 107731 107715 Dec-Mar Avg Temp (0C) DFN -411 054305 063471 069105 068059 Apr Prec - PET (mm) DFamp 223 003842 003889 004869 May Prec - PET (mm) DFI -3164 -002818 -002756 Jun Prec - PET (mm) DFN -5621 002180

R Squared 081682 085246 086025 086928 087596 Standard Error (QHa) 263715 240863 238720 235275 233725 Standard Variance (QHa) 695458 580150 569874 553542 546273

Standard Deviation of Yields = 595955 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 1 and 2 =DFNSquared Departure from Normal Yields Based on 1958-1973

Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1973

May 1977

NORTH UKRAINE WINTER WHEAT COVARIANCE MODEL

Region

West Ukraine - Crop Region 3 North Central Ukraine - Crop Region 4 Northeast Ukraine - Crop Region 5

PET A = 1030 PET I = 33428

April Daylength = 11393 May Daylength 12773 June Daylength = 13460

Latitude = 50ON

Crop Region 3 Constant Crop Region 4 Constant

= 1 if Data from Crop Region 3 Otherwise 0 = 1 if Data from Crop Region 4 Otherwise 0

Variable Deviation Normal Trend March April May June

Overall Constant Region 3 Constant Region 4 Constant Linear Trend (1958-1973) Sep-Mar Pree (mm) Dec-Mar Temp (degC) Dec-Mar Temp (degC) Apr Prec - PET (mm) May Prec - PET (mm) May Pree - PET (mm) Jun Prec - PET (mnn) Jun Prec - PET (mm)

DFN DEN SDFN DEN DFN SDFN DFN SDFN

100 100 100

1600 28765 -296 -296 -698

-3672 -3672 -5252 -5252

1402232 -112029 041235 090861

1703209 -401435 -134084 084046 000779 131408

-023401

1691113 -456768 -139607 085960 000595 138943

-019124 003334

1767622 -532192 -150568 083308 000476 132271

-014792 004418 002763

-000046

1926082 -673875 -153973 074242 000371 111158

-009266 001664 004871

-000063 003712

-000028

R Squared Standard Error (QHa) Standard Variance (QHa)

058101 375913

1413103

079652 271383 736489

080477 269128 724300

082606 260628 679269

084547 252388 636995

Standard Deviation of Yields = 561906 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled over Crop Regions 3 4 and 5 SDFN = Squared Departure from Normal Yields Based on 1958-1973 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1973

May 1977

UKRAINE-KRASNODAR WINTER WHEAT COVARIANCE MODEL

Region

Eastern Ukraine - Crop Region 6 Southern Ukraine - Crop Region 7 Krasnodar - Crop Region 9

PET A 1206 April Daylength = 11251 Latitude = 47degN PET I 45130

Crop Region 6 Constant = I if Data from Crop Region 6 Otherwise 0 Crop Region 7 Constant = 1 if Data from Crop Region 7 Otherwise 0

Variable Deviation Normal Trend February March April

Overall Constant Region 6 Constant Region 7 Constant Linear Trend (1958-1973) Jan-Feb Temp (degC) Jan-Feb Temp (degC) Sep-Mar Prec (mm) Apr Prec - PET (mm)

DFN SDFN DFN DFN

100 100 100

1500 -231 -231 30267 -1128

2208902 -606706 -533688 056707

1813271 -182993 -469991 092905 126688

-006415

1784735 -106709 -345187 087673 115271

-006032 001385

1703027 -080185 -316404 095955 121937

-006372 001332 003454

R Squared Standard Error (QHa)

046541 409730

076945 275885

079243 265198

080735 258917

Standard Variance (QHa) 1678789 761124 703298 670382

Standard Deviation of Yields = 540947 QhHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields and Climatic data are Pooled Over Crop Regions 6 7 and 9 Yields Based on 1958-1972 Meteorological Normals Based on 1958-1972

May 1977

MOLDAVIA WINTER WHEAT MODEL

Region

Moldavia - Crop Region 8

PET A PET I

1186 43795

March Daylength = 9808 April Daylength - 11251

Latitude 47 N

Variable Deviation Normal Trend February March April June July

Constant Linear Trend (1958-1973) Jan-Feb Avg Temp (0C) Mar Prec - PET (mm) Apr Prec - PET (mm) Jun Temp (0C) Jul Prec (mm)

DFN DFN DFN DFN DFN

100 1600 -226 2081

-1421 1886 6063

1049481 120124

909938 136541 125431

833258 145563 120052

-006288

738836 156671 125488

-007146 006763

697522 161532 084182

-014263 006089

-223464

465335 188847 084113

-010165 008502

-139325 -007373

R Squared Standard Error (QHa) Standard Variance (QHa)

050283 588632

3464873

063447 523781

2743462

066253 523821 2743881

071022 506981

2570300

076977 473951

2246297

080253 462680

2140732

Standard Deviation of Yields = 806514 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

CAUCASUS-VOLGA WINTER WHfEAT COVARIANCE MODEL

Region

Northeast Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1184 May Dayiength = 12573 Latitude = 480 N PET I = 43641

Crop Region 10 Constant 1 if Data from Crop Region 10 Otherwise 0

Variable Deviation Normal Trend March April May

Overall Constant Region 10 Constant Sep-Mar Pree (mm) Nov-Mar Temp (0C) Nov-Mar Temp (degC) Apr Temp (C)

Apr Temp (00) May Prec - PET (mm) May Prec - PET (mm)

DFN DFN SDFN DFN SDFN DFN SDFN

100 100

23375 -298 -298 917 917

-5703 -5703

1435914 135574

1663994 -247534 002834 112799 -006090

1677922 -255532 002759 092628

-009846 050509 003074

1816074 -252471 002877 074880

-010528 061397

-006899 005800

-000141

R Squared Standard Error (QHa) Standard Variance (QHa)

002583 432000

1866241

052925 319291

1019468

056642 320685

1028391

070205 279479 781085

Standard Deviation of Yields = 429508 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 10 and 17 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

APPENDIX

USSR SPRING WHEAT MODELS

Black Soil Zone South Kazakhstan

11 WestBlack Soil Zone 29 South Kazakhstan 12 East Black Soil Zone

Central Asia Central District

30 Central Asia 13 Central Region

Eastern Siberia Volga-Vyatsk 31 Eastern Siberia

14 Volga-Vyatsk

Far East Upper Volga

32 Far East

15 Upper Volga Northwest

Middle Volga 33 Northwest

16 Middle Volga

Caucasus-Volga

10 Northeast Caucasus 17 Lower Volga

Northwest Urals

18 Northwestern Urals

Southern Urals-Western Kazakhstan

19 Southern Urals 21 Western Kazakhstan

Northeastern Urals

20 Northeastern Urals

Northeast Kazakh

22 Kustanay 23 Tselinograd 24 Northern Kazakhstan 25 Pavlodar

Siberia-Altai

26 Western Siberia 27 Altai Krai

A-2

BALTICS-BELORUSSIA WINTER WHEAT COVARIANCE MODEL

Region

Baltics - Crop Region I

Belorussia - Crop Region 2

PET A = 946 April Daylength = 11674 Latitude = 55degN PET I = 27816 May Daylength = 13374

June Daylength = 14254

Crop Region 1 Constant = 1 if Data from Crop Region 1 Otherwise 0

Variable Deviation Normal Trend March April May June

Overall Constant 100 433592 456263 488144 482387 479744 Region 1 Constant 100 281226 234473 220686 237189 242756 Linear Trend (1958-1973) 1600 110882 110965 108025 107731 107715 Dec-Mar Avg Temp (0C) DFN -411 054305 063471 069105 068059 Apr Prec - PET (mm) DFamp 223 003842 003889 004869 May Prec - PET (mm) DFI -3164 -002818 -002756 Jun Prec - PET (mm) DFN -5621 002180

R Squared 081682 085246 086025 086928 087596 Standard Error (QHa) 263715 240863 238720 235275 233725 Standard Variance (QHa) 695458 580150 569874 553542 546273

Standard Deviation of Yields = 595955 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 1 and 2 =DFNSquared Departure from Normal Yields Based on 1958-1973

Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1973

May 1977

NORTH UKRAINE WINTER WHEAT COVARIANCE MODEL

Region

West Ukraine - Crop Region 3 North Central Ukraine - Crop Region 4 Northeast Ukraine - Crop Region 5

PET A = 1030 PET I = 33428

April Daylength = 11393 May Daylength 12773 June Daylength = 13460

Latitude = 50ON

Crop Region 3 Constant Crop Region 4 Constant

= 1 if Data from Crop Region 3 Otherwise 0 = 1 if Data from Crop Region 4 Otherwise 0

Variable Deviation Normal Trend March April May June

Overall Constant Region 3 Constant Region 4 Constant Linear Trend (1958-1973) Sep-Mar Pree (mm) Dec-Mar Temp (degC) Dec-Mar Temp (degC) Apr Prec - PET (mm) May Prec - PET (mm) May Pree - PET (mm) Jun Prec - PET (mnn) Jun Prec - PET (mm)

DFN DEN SDFN DEN DFN SDFN DFN SDFN

100 100 100

1600 28765 -296 -296 -698

-3672 -3672 -5252 -5252

1402232 -112029 041235 090861

1703209 -401435 -134084 084046 000779 131408

-023401

1691113 -456768 -139607 085960 000595 138943

-019124 003334

1767622 -532192 -150568 083308 000476 132271

-014792 004418 002763

-000046

1926082 -673875 -153973 074242 000371 111158

-009266 001664 004871

-000063 003712

-000028

R Squared Standard Error (QHa) Standard Variance (QHa)

058101 375913

1413103

079652 271383 736489

080477 269128 724300

082606 260628 679269

084547 252388 636995

Standard Deviation of Yields = 561906 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled over Crop Regions 3 4 and 5 SDFN = Squared Departure from Normal Yields Based on 1958-1973 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1973

May 1977

UKRAINE-KRASNODAR WINTER WHEAT COVARIANCE MODEL

Region

Eastern Ukraine - Crop Region 6 Southern Ukraine - Crop Region 7 Krasnodar - Crop Region 9

PET A 1206 April Daylength = 11251 Latitude = 47degN PET I 45130

Crop Region 6 Constant = I if Data from Crop Region 6 Otherwise 0 Crop Region 7 Constant = 1 if Data from Crop Region 7 Otherwise 0

Variable Deviation Normal Trend February March April

Overall Constant Region 6 Constant Region 7 Constant Linear Trend (1958-1973) Jan-Feb Temp (degC) Jan-Feb Temp (degC) Sep-Mar Prec (mm) Apr Prec - PET (mm)

DFN SDFN DFN DFN

100 100 100

1500 -231 -231 30267 -1128

2208902 -606706 -533688 056707

1813271 -182993 -469991 092905 126688

-006415

1784735 -106709 -345187 087673 115271

-006032 001385

1703027 -080185 -316404 095955 121937

-006372 001332 003454

R Squared Standard Error (QHa)

046541 409730

076945 275885

079243 265198

080735 258917

Standard Variance (QHa) 1678789 761124 703298 670382

Standard Deviation of Yields = 540947 QhHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields and Climatic data are Pooled Over Crop Regions 6 7 and 9 Yields Based on 1958-1972 Meteorological Normals Based on 1958-1972

May 1977

MOLDAVIA WINTER WHEAT MODEL

Region

Moldavia - Crop Region 8

PET A PET I

1186 43795

March Daylength = 9808 April Daylength - 11251

Latitude 47 N

Variable Deviation Normal Trend February March April June July

Constant Linear Trend (1958-1973) Jan-Feb Avg Temp (0C) Mar Prec - PET (mm) Apr Prec - PET (mm) Jun Temp (0C) Jul Prec (mm)

DFN DFN DFN DFN DFN

100 1600 -226 2081

-1421 1886 6063

1049481 120124

909938 136541 125431

833258 145563 120052

-006288

738836 156671 125488

-007146 006763

697522 161532 084182

-014263 006089

-223464

465335 188847 084113

-010165 008502

-139325 -007373

R Squared Standard Error (QHa) Standard Variance (QHa)

050283 588632

3464873

063447 523781

2743462

066253 523821 2743881

071022 506981

2570300

076977 473951

2246297

080253 462680

2140732

Standard Deviation of Yields = 806514 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

CAUCASUS-VOLGA WINTER WHfEAT COVARIANCE MODEL

Region

Northeast Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1184 May Dayiength = 12573 Latitude = 480 N PET I = 43641

Crop Region 10 Constant 1 if Data from Crop Region 10 Otherwise 0

Variable Deviation Normal Trend March April May

Overall Constant Region 10 Constant Sep-Mar Pree (mm) Nov-Mar Temp (0C) Nov-Mar Temp (degC) Apr Temp (C)

Apr Temp (00) May Prec - PET (mm) May Prec - PET (mm)

DFN DFN SDFN DFN SDFN DFN SDFN

100 100

23375 -298 -298 917 917

-5703 -5703

1435914 135574

1663994 -247534 002834 112799 -006090

1677922 -255532 002759 092628

-009846 050509 003074

1816074 -252471 002877 074880

-010528 061397

-006899 005800

-000141

R Squared Standard Error (QHa) Standard Variance (QHa)

002583 432000

1866241

052925 319291

1019468

056642 320685

1028391

070205 279479 781085

Standard Deviation of Yields = 429508 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 10 and 17 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

BALTICS-BELORUSSIA WINTER WHEAT COVARIANCE MODEL

Region

Baltics - Crop Region I

Belorussia - Crop Region 2

PET A = 946 April Daylength = 11674 Latitude = 55degN PET I = 27816 May Daylength = 13374

June Daylength = 14254

Crop Region 1 Constant = 1 if Data from Crop Region 1 Otherwise 0

Variable Deviation Normal Trend March April May June

Overall Constant 100 433592 456263 488144 482387 479744 Region 1 Constant 100 281226 234473 220686 237189 242756 Linear Trend (1958-1973) 1600 110882 110965 108025 107731 107715 Dec-Mar Avg Temp (0C) DFN -411 054305 063471 069105 068059 Apr Prec - PET (mm) DFamp 223 003842 003889 004869 May Prec - PET (mm) DFI -3164 -002818 -002756 Jun Prec - PET (mm) DFN -5621 002180

R Squared 081682 085246 086025 086928 087596 Standard Error (QHa) 263715 240863 238720 235275 233725 Standard Variance (QHa) 695458 580150 569874 553542 546273

Standard Deviation of Yields = 595955 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 1 and 2 =DFNSquared Departure from Normal Yields Based on 1958-1973

Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1973

May 1977

NORTH UKRAINE WINTER WHEAT COVARIANCE MODEL

Region

West Ukraine - Crop Region 3 North Central Ukraine - Crop Region 4 Northeast Ukraine - Crop Region 5

PET A = 1030 PET I = 33428

April Daylength = 11393 May Daylength 12773 June Daylength = 13460

Latitude = 50ON

Crop Region 3 Constant Crop Region 4 Constant

= 1 if Data from Crop Region 3 Otherwise 0 = 1 if Data from Crop Region 4 Otherwise 0

Variable Deviation Normal Trend March April May June

Overall Constant Region 3 Constant Region 4 Constant Linear Trend (1958-1973) Sep-Mar Pree (mm) Dec-Mar Temp (degC) Dec-Mar Temp (degC) Apr Prec - PET (mm) May Prec - PET (mm) May Pree - PET (mm) Jun Prec - PET (mnn) Jun Prec - PET (mm)

DFN DEN SDFN DEN DFN SDFN DFN SDFN

100 100 100

1600 28765 -296 -296 -698

-3672 -3672 -5252 -5252

1402232 -112029 041235 090861

1703209 -401435 -134084 084046 000779 131408

-023401

1691113 -456768 -139607 085960 000595 138943

-019124 003334

1767622 -532192 -150568 083308 000476 132271

-014792 004418 002763

-000046

1926082 -673875 -153973 074242 000371 111158

-009266 001664 004871

-000063 003712

-000028

R Squared Standard Error (QHa) Standard Variance (QHa)

058101 375913

1413103

079652 271383 736489

080477 269128 724300

082606 260628 679269

084547 252388 636995

Standard Deviation of Yields = 561906 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled over Crop Regions 3 4 and 5 SDFN = Squared Departure from Normal Yields Based on 1958-1973 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1973

May 1977

UKRAINE-KRASNODAR WINTER WHEAT COVARIANCE MODEL

Region

Eastern Ukraine - Crop Region 6 Southern Ukraine - Crop Region 7 Krasnodar - Crop Region 9

PET A 1206 April Daylength = 11251 Latitude = 47degN PET I 45130

Crop Region 6 Constant = I if Data from Crop Region 6 Otherwise 0 Crop Region 7 Constant = 1 if Data from Crop Region 7 Otherwise 0

Variable Deviation Normal Trend February March April

Overall Constant Region 6 Constant Region 7 Constant Linear Trend (1958-1973) Jan-Feb Temp (degC) Jan-Feb Temp (degC) Sep-Mar Prec (mm) Apr Prec - PET (mm)

DFN SDFN DFN DFN

100 100 100

1500 -231 -231 30267 -1128

2208902 -606706 -533688 056707

1813271 -182993 -469991 092905 126688

-006415

1784735 -106709 -345187 087673 115271

-006032 001385

1703027 -080185 -316404 095955 121937

-006372 001332 003454

R Squared Standard Error (QHa)

046541 409730

076945 275885

079243 265198

080735 258917

Standard Variance (QHa) 1678789 761124 703298 670382

Standard Deviation of Yields = 540947 QhHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields and Climatic data are Pooled Over Crop Regions 6 7 and 9 Yields Based on 1958-1972 Meteorological Normals Based on 1958-1972

May 1977

MOLDAVIA WINTER WHEAT MODEL

Region

Moldavia - Crop Region 8

PET A PET I

1186 43795

March Daylength = 9808 April Daylength - 11251

Latitude 47 N

Variable Deviation Normal Trend February March April June July

Constant Linear Trend (1958-1973) Jan-Feb Avg Temp (0C) Mar Prec - PET (mm) Apr Prec - PET (mm) Jun Temp (0C) Jul Prec (mm)

DFN DFN DFN DFN DFN

100 1600 -226 2081

-1421 1886 6063

1049481 120124

909938 136541 125431

833258 145563 120052

-006288

738836 156671 125488

-007146 006763

697522 161532 084182

-014263 006089

-223464

465335 188847 084113

-010165 008502

-139325 -007373

R Squared Standard Error (QHa) Standard Variance (QHa)

050283 588632

3464873

063447 523781

2743462

066253 523821 2743881

071022 506981

2570300

076977 473951

2246297

080253 462680

2140732

Standard Deviation of Yields = 806514 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

CAUCASUS-VOLGA WINTER WHfEAT COVARIANCE MODEL

Region

Northeast Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1184 May Dayiength = 12573 Latitude = 480 N PET I = 43641

Crop Region 10 Constant 1 if Data from Crop Region 10 Otherwise 0

Variable Deviation Normal Trend March April May

Overall Constant Region 10 Constant Sep-Mar Pree (mm) Nov-Mar Temp (0C) Nov-Mar Temp (degC) Apr Temp (C)

Apr Temp (00) May Prec - PET (mm) May Prec - PET (mm)

DFN DFN SDFN DFN SDFN DFN SDFN

100 100

23375 -298 -298 917 917

-5703 -5703

1435914 135574

1663994 -247534 002834 112799 -006090

1677922 -255532 002759 092628

-009846 050509 003074

1816074 -252471 002877 074880

-010528 061397

-006899 005800

-000141

R Squared Standard Error (QHa) Standard Variance (QHa)

002583 432000

1866241

052925 319291

1019468

056642 320685

1028391

070205 279479 781085

Standard Deviation of Yields = 429508 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 10 and 17 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

NORTH UKRAINE WINTER WHEAT COVARIANCE MODEL

Region

West Ukraine - Crop Region 3 North Central Ukraine - Crop Region 4 Northeast Ukraine - Crop Region 5

PET A = 1030 PET I = 33428

April Daylength = 11393 May Daylength 12773 June Daylength = 13460

Latitude = 50ON

Crop Region 3 Constant Crop Region 4 Constant

= 1 if Data from Crop Region 3 Otherwise 0 = 1 if Data from Crop Region 4 Otherwise 0

Variable Deviation Normal Trend March April May June

Overall Constant Region 3 Constant Region 4 Constant Linear Trend (1958-1973) Sep-Mar Pree (mm) Dec-Mar Temp (degC) Dec-Mar Temp (degC) Apr Prec - PET (mm) May Prec - PET (mm) May Pree - PET (mm) Jun Prec - PET (mnn) Jun Prec - PET (mm)

DFN DEN SDFN DEN DFN SDFN DFN SDFN

100 100 100

1600 28765 -296 -296 -698

-3672 -3672 -5252 -5252

1402232 -112029 041235 090861

1703209 -401435 -134084 084046 000779 131408

-023401

1691113 -456768 -139607 085960 000595 138943

-019124 003334

1767622 -532192 -150568 083308 000476 132271

-014792 004418 002763

-000046

1926082 -673875 -153973 074242 000371 111158

-009266 001664 004871

-000063 003712

-000028

R Squared Standard Error (QHa) Standard Variance (QHa)

058101 375913

1413103

079652 271383 736489

080477 269128 724300

082606 260628 679269

084547 252388 636995

Standard Deviation of Yields = 561906 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled over Crop Regions 3 4 and 5 SDFN = Squared Departure from Normal Yields Based on 1958-1973 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1973

May 1977

UKRAINE-KRASNODAR WINTER WHEAT COVARIANCE MODEL

Region

Eastern Ukraine - Crop Region 6 Southern Ukraine - Crop Region 7 Krasnodar - Crop Region 9

PET A 1206 April Daylength = 11251 Latitude = 47degN PET I 45130

Crop Region 6 Constant = I if Data from Crop Region 6 Otherwise 0 Crop Region 7 Constant = 1 if Data from Crop Region 7 Otherwise 0

Variable Deviation Normal Trend February March April

Overall Constant Region 6 Constant Region 7 Constant Linear Trend (1958-1973) Jan-Feb Temp (degC) Jan-Feb Temp (degC) Sep-Mar Prec (mm) Apr Prec - PET (mm)

DFN SDFN DFN DFN

100 100 100

1500 -231 -231 30267 -1128

2208902 -606706 -533688 056707

1813271 -182993 -469991 092905 126688

-006415

1784735 -106709 -345187 087673 115271

-006032 001385

1703027 -080185 -316404 095955 121937

-006372 001332 003454

R Squared Standard Error (QHa)

046541 409730

076945 275885

079243 265198

080735 258917

Standard Variance (QHa) 1678789 761124 703298 670382

Standard Deviation of Yields = 540947 QhHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields and Climatic data are Pooled Over Crop Regions 6 7 and 9 Yields Based on 1958-1972 Meteorological Normals Based on 1958-1972

May 1977

MOLDAVIA WINTER WHEAT MODEL

Region

Moldavia - Crop Region 8

PET A PET I

1186 43795

March Daylength = 9808 April Daylength - 11251

Latitude 47 N

Variable Deviation Normal Trend February March April June July

Constant Linear Trend (1958-1973) Jan-Feb Avg Temp (0C) Mar Prec - PET (mm) Apr Prec - PET (mm) Jun Temp (0C) Jul Prec (mm)

DFN DFN DFN DFN DFN

100 1600 -226 2081

-1421 1886 6063

1049481 120124

909938 136541 125431

833258 145563 120052

-006288

738836 156671 125488

-007146 006763

697522 161532 084182

-014263 006089

-223464

465335 188847 084113

-010165 008502

-139325 -007373

R Squared Standard Error (QHa) Standard Variance (QHa)

050283 588632

3464873

063447 523781

2743462

066253 523821 2743881

071022 506981

2570300

076977 473951

2246297

080253 462680

2140732

Standard Deviation of Yields = 806514 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

CAUCASUS-VOLGA WINTER WHfEAT COVARIANCE MODEL

Region

Northeast Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1184 May Dayiength = 12573 Latitude = 480 N PET I = 43641

Crop Region 10 Constant 1 if Data from Crop Region 10 Otherwise 0

Variable Deviation Normal Trend March April May

Overall Constant Region 10 Constant Sep-Mar Pree (mm) Nov-Mar Temp (0C) Nov-Mar Temp (degC) Apr Temp (C)

Apr Temp (00) May Prec - PET (mm) May Prec - PET (mm)

DFN DFN SDFN DFN SDFN DFN SDFN

100 100

23375 -298 -298 917 917

-5703 -5703

1435914 135574

1663994 -247534 002834 112799 -006090

1677922 -255532 002759 092628

-009846 050509 003074

1816074 -252471 002877 074880

-010528 061397

-006899 005800

-000141

R Squared Standard Error (QHa) Standard Variance (QHa)

002583 432000

1866241

052925 319291

1019468

056642 320685

1028391

070205 279479 781085

Standard Deviation of Yields = 429508 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 10 and 17 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

UKRAINE-KRASNODAR WINTER WHEAT COVARIANCE MODEL

Region

Eastern Ukraine - Crop Region 6 Southern Ukraine - Crop Region 7 Krasnodar - Crop Region 9

PET A 1206 April Daylength = 11251 Latitude = 47degN PET I 45130

Crop Region 6 Constant = I if Data from Crop Region 6 Otherwise 0 Crop Region 7 Constant = 1 if Data from Crop Region 7 Otherwise 0

Variable Deviation Normal Trend February March April

Overall Constant Region 6 Constant Region 7 Constant Linear Trend (1958-1973) Jan-Feb Temp (degC) Jan-Feb Temp (degC) Sep-Mar Prec (mm) Apr Prec - PET (mm)

DFN SDFN DFN DFN

100 100 100

1500 -231 -231 30267 -1128

2208902 -606706 -533688 056707

1813271 -182993 -469991 092905 126688

-006415

1784735 -106709 -345187 087673 115271

-006032 001385

1703027 -080185 -316404 095955 121937

-006372 001332 003454

R Squared Standard Error (QHa)

046541 409730

076945 275885

079243 265198

080735 258917

Standard Variance (QHa) 1678789 761124 703298 670382

Standard Deviation of Yields = 540947 QhHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields and Climatic data are Pooled Over Crop Regions 6 7 and 9 Yields Based on 1958-1972 Meteorological Normals Based on 1958-1972

May 1977

MOLDAVIA WINTER WHEAT MODEL

Region

Moldavia - Crop Region 8

PET A PET I

1186 43795

March Daylength = 9808 April Daylength - 11251

Latitude 47 N

Variable Deviation Normal Trend February March April June July

Constant Linear Trend (1958-1973) Jan-Feb Avg Temp (0C) Mar Prec - PET (mm) Apr Prec - PET (mm) Jun Temp (0C) Jul Prec (mm)

DFN DFN DFN DFN DFN

100 1600 -226 2081

-1421 1886 6063

1049481 120124

909938 136541 125431

833258 145563 120052

-006288

738836 156671 125488

-007146 006763

697522 161532 084182

-014263 006089

-223464

465335 188847 084113

-010165 008502

-139325 -007373

R Squared Standard Error (QHa) Standard Variance (QHa)

050283 588632

3464873

063447 523781

2743462

066253 523821 2743881

071022 506981

2570300

076977 473951

2246297

080253 462680

2140732

Standard Deviation of Yields = 806514 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

CAUCASUS-VOLGA WINTER WHfEAT COVARIANCE MODEL

Region

Northeast Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1184 May Dayiength = 12573 Latitude = 480 N PET I = 43641

Crop Region 10 Constant 1 if Data from Crop Region 10 Otherwise 0

Variable Deviation Normal Trend March April May

Overall Constant Region 10 Constant Sep-Mar Pree (mm) Nov-Mar Temp (0C) Nov-Mar Temp (degC) Apr Temp (C)

Apr Temp (00) May Prec - PET (mm) May Prec - PET (mm)

DFN DFN SDFN DFN SDFN DFN SDFN

100 100

23375 -298 -298 917 917

-5703 -5703

1435914 135574

1663994 -247534 002834 112799 -006090

1677922 -255532 002759 092628

-009846 050509 003074

1816074 -252471 002877 074880

-010528 061397

-006899 005800

-000141

R Squared Standard Error (QHa) Standard Variance (QHa)

002583 432000

1866241

052925 319291

1019468

056642 320685

1028391

070205 279479 781085

Standard Deviation of Yields = 429508 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 10 and 17 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

MOLDAVIA WINTER WHEAT MODEL

Region

Moldavia - Crop Region 8

PET A PET I

1186 43795

March Daylength = 9808 April Daylength - 11251

Latitude 47 N

Variable Deviation Normal Trend February March April June July

Constant Linear Trend (1958-1973) Jan-Feb Avg Temp (0C) Mar Prec - PET (mm) Apr Prec - PET (mm) Jun Temp (0C) Jul Prec (mm)

DFN DFN DFN DFN DFN

100 1600 -226 2081

-1421 1886 6063

1049481 120124

909938 136541 125431

833258 145563 120052

-006288

738836 156671 125488

-007146 006763

697522 161532 084182

-014263 006089

-223464

465335 188847 084113

-010165 008502

-139325 -007373

R Squared Standard Error (QHa) Standard Variance (QHa)

050283 588632

3464873

063447 523781

2743462

066253 523821 2743881

071022 506981

2570300

076977 473951

2246297

080253 462680

2140732

Standard Deviation of Yields = 806514 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

CAUCASUS-VOLGA WINTER WHfEAT COVARIANCE MODEL

Region

Northeast Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1184 May Dayiength = 12573 Latitude = 480 N PET I = 43641

Crop Region 10 Constant 1 if Data from Crop Region 10 Otherwise 0

Variable Deviation Normal Trend March April May

Overall Constant Region 10 Constant Sep-Mar Pree (mm) Nov-Mar Temp (0C) Nov-Mar Temp (degC) Apr Temp (C)

Apr Temp (00) May Prec - PET (mm) May Prec - PET (mm)

DFN DFN SDFN DFN SDFN DFN SDFN

100 100

23375 -298 -298 917 917

-5703 -5703

1435914 135574

1663994 -247534 002834 112799 -006090

1677922 -255532 002759 092628

-009846 050509 003074

1816074 -252471 002877 074880

-010528 061397

-006899 005800

-000141

R Squared Standard Error (QHa) Standard Variance (QHa)

002583 432000

1866241

052925 319291

1019468

056642 320685

1028391

070205 279479 781085

Standard Deviation of Yields = 429508 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 10 and 17 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

CAUCASUS-VOLGA WINTER WHfEAT COVARIANCE MODEL

Region

Northeast Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1184 May Dayiength = 12573 Latitude = 480 N PET I = 43641

Crop Region 10 Constant 1 if Data from Crop Region 10 Otherwise 0

Variable Deviation Normal Trend March April May

Overall Constant Region 10 Constant Sep-Mar Pree (mm) Nov-Mar Temp (0C) Nov-Mar Temp (degC) Apr Temp (C)

Apr Temp (00) May Prec - PET (mm) May Prec - PET (mm)

DFN DFN SDFN DFN SDFN DFN SDFN

100 100

23375 -298 -298 917 917

-5703 -5703

1435914 135574

1663994 -247534 002834 112799 -006090

1677922 -255532 002759 092628

-009846 050509 003074

1816074 -252471 002877 074880

-010528 061397

-006899 005800

-000141

R Squared Standard Error (QHa) Standard Variance (QHa)

002583 432000

1866241

052925 319291

1019468

056642 320685

1028391

070205 279479 781085

Standard Deviation of Yields = 429508 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 10 and 17 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

BLACK SOIL ZONE WINTER WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 May Daylength = 12880 Latitude = 510N PET I = 32810

Crop Region 12 Constant = 1 if Data from Crop Region 12 Otherwise 0

Variable Deviation Normal Trend February March April May

Overall Constant 100 1263277 972778 1039611 1110661 1100843 Region 12 Constant 100 065617 180616 168806 185011 176580 Linear Trend (1958-1971) 1400 047866 078932 070808 063560 064652 Jan-Feb Temp (oC) DFN -776 084960 064729 036669 032586 Mar Temp (degC) DFN -314 032550 070083 067848 Apr Prec (mm) DFN 3600 003461 003232 Apr Prec (mm) SDFN 360 000262 000274

to Apr Temp (0Q) SDFN 660 -017461 -016711 May Prec - PET (mm) DFN -4395 001999

R Squared 022628 K 062085 063946 075049 077045 Standard Error (QHa) 383018 273651 272588 243180 239308 Standard Variance (QHa) 1467027 748847 743044 591366 572683

Standard Deviation of Yields = 419001 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

CENTRAL DISTRICT WINTER WHEAT MODEL

Region

Central District - Crop Region 13

PET A = 937 May Daylength - 13517 Latitude = 56ON PET I = 27226

Variable Deviation Normal Trend March April May

Overall Constant 100 698680 661694 743347 808181 Linear Trend (1958-1973) 1600 065394 069745 067756 062374 Dec-Mar Temp (OC) DFN -735 035037 033625 025120 Apr Temp (0) SDFN 531 -018615 -024105 May Prec - PET (mm) DFN -3604 003500

R Squared 071230 077284 082751 086092 Standard Error (QHa) 204810 188861 171292 160651 Standard Variance (QHa) 419473 356687 293409 258087

Standard Deviation of Yields = 368892 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

VOLGA-VYATSK WINTER WHEAT MODEL

Region

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude = 560N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant Linear Trend (1958-1973) Apr Temp (OC) Apr Temp (Oc) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm)

DIN SDFN DFN DEN SDFN

100 1600 381 381

-3941 -5599 -5599

870076 040203

991247 042958

018745 -027819

1042161 031702 036502

-019206 005659

1092689 025930 050192

-002053 006963 006491 -000118

L R Squared Standard Error (QHa) Standard Variance (QHa)

035399 267641 716317

057413 234717 550921

072518 196935 387834

083989 166181 276161

Standard Deviation of Yields = 321701 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1973 Meteorological Normals Based on 1958-1973

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

UPPER VOLGA WINTER WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 May Daylength = 13240 Latitude =540N PET I = 29088 June Daylength = 14074

Variable Deviation Normal Trend April June

Overall Constant 100 868658 lb09648 1031692 Linear Tread (1958-1971) 1200 064203 070462 064266 Apr Temp ( C) DFN 381 031508 032207 Apr Temp (degC) SDFN 381 -042804 -037505 Jun Pree - PET (mm) DFN -6626 004861

R Squared 044277 075727 084134 Standard Error (QHa) 290232 209838 178825 Standard Variance (QHa) 842344 440319 319785

Standard Deviation of Yields = 373550 QHa

DFN = Departure from Normal Yields Based on 1958-1971 SDN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

MIDDLE VOLGA WINTER WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 May Daylength = 12994 Latitude 52degN PET I = 35238

Variable Deviation Normal April may

Overall Constant 100 1620480 1654855 Apr Temp (0C) DFN 623 096544 172873 Apr Temp (0C) SDFN 623 -039161 -046741 May Prec - PET (mm) DFN -5929 016253

R Squared 033013 080749 Standard Error (QHa) 398903 224280 Standard Variance (QHa) 1591238 503017

Standard Deviation of Yields = 448328 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

NORTHWEST URALS WINTER WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 PET I = 23120

May Daylength = 13834 June Daylength = 14885 July Daylength = 14247

Latitude = 580N

Variable Deviation Normal March April May June July

Overall Constant Dec-Mar Temp (C) Dec-Mar Temp (C) Apr Temp (C) May Prec - PET (mm) Jun Prec - PET (mm) Jun Prec - PET (mm) Jul Pree - PET (mm)

DFN SDFN DFN DFN DEN SDFN DEN

100 -1168 -1168

287 -4475 -6152 -6152 -6047

1135794 007397

-020443

1207928 021037

-032667 055667

1163479 025064

-022040 067742 003711

1201433 034808

-017960 083435 004858

-000761 -000064

1200717 034215

-014958 093487 005975

-000407 -000091 -001758

R Squared

Standard Error (QHa) Standard Variance (QHa)

029633 197784 391186

050815 175387 307605

069021 148802 221420

078888 145348 211260

082644 147342 217097

Standard Deviation of Yields = 213270 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1969 Meteorological Normals Based on 1958-1973

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

TRANSCAUCASUS WINT-R WHEAT MODEL

Transcaucasus - Crop Region 28

PET A = 1441 June Daylength = 12463 Latitude = 410N PET I = 60315

Variable Deviation Normal Trend April May June

Overall Constant 100 713531 748573 757169 764755 Linear Trend (1958-1974) 1700 047916 048970 046731 047485 Apr Prec (mm) DFN 2682 -002195 -002818 -003459 Apt Prec (mm) SDFN 2682 -000340 -000252 -000208 May Temp (0C) DFN 1819 -031632 -005342 Jun Prec - PET (mm) DFN -10697 002749 Jun Prec - PET (mm) SDFN -10697 -000063

R Squared 076412 080493 081955 087758 Standard Error (QHa) 138844 135629 135774 122506 Standard Variance (QHa) 192776 183951 184345 150077

Standard Deviation of Yields = 276801 QHa

DEN Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1974 Yields Measured in Quintals per Hectare

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

SOUTH KAZAKHSTAN WINTER WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET I = 1365 May Daylength = 12066 Latitude = 420N PET A = 55497

Variable Deviation Normal Constant March April May June

Overall Constant Dec-Mar Temp (C) Apr Temp (0C) Apr Temp (C) May Pree - ThET (mm) May Prec - PET (mm) Jun Temp (degC)

DFN DFN SDFN DFN SDN DFN

100 044

1286 1286

-4462 -4462 2321

1045508 1045508 020381

1070239 016862

-062323 -012794

1199482 010457

-016378 -008628 006023 -000121

1188507 015290

-021217 -006721 005791

-000115 -047889

R Squared Standard Error (QKa) Standard Variance (QHa)

000000 300576 903459

002432 306636 940255

014520 308301 950495

065295 213556 456060

066878 218812 478788

Standard Deviation of Yields = 300576 QHa

DFN = Departure from Normal Yields Based on 1958-1974 SDFN = Squared Departure from Normal Meteorological Normals Based on 1957-1974 Yields Measured in Quintals per Hectare

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

CENTRAL ASIAWINTER WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = 1421 PET I = 59091

April Daylength = 10977 May Daylength = 11921

Latitude = 400N

Variable Deviation Normal Trend March April May June

Overall Constant Linear Trend (1958-1974) Nov-Mar Pree (m) Apr Prec - PET (mm) May Prec - PET (mm) Jun Temp (oC)

DFN DFN DFN DFN

100 1700

24171 2417

-5230 2415

566360 029145

520955 034190 001265

526420 033583 001185 000771

553685 030553 000623 000129 001897

542305 031818 000739 000123 001828

-015456

R Squared Standard Error (QHa) Standard Variance (QHa)

055286 136695 186856

067740 120184 144441

069627 121019 146456

075215 113784 129467

075529 118088 139448

Standard Deviation of Yields = 197934 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

NORTHWEST WINTER WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = PET I =

891 24247

May Daylength June Daylength JulyDaylength

13834 14885 14247

Latitude = 58degN

Variable Deviation Normal Trend March May June July

Overall Constant Linear Trend (1958-1971) Sep-liar Prec (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (nu)

DEN DFN DEN DFN

100 1400 28171 -3118 -6383 -6154

825618 032679

807855 034996 -000462

802580 035804 -000359 -000764

817219 033897

-000303 -000919 -000529

815096 036044 000953

-001702 -001552 -004188

R Squared Standard Error (QHa) Standard Variance (QHa)

059864 121037 146500

060864 125354 157136

062479 129380 167393

063189 135924 184753

086430 088224 077834

Standard Deviation of Yields = 182919 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1965 and 1967-1971 Meteorological Normals Based on 1958-1971

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

CAUCASUS-VOLGA SPRING WIEAT COVARIANCE MODEL

Region

Northeastern Caucasus - Crop Region 10 Lower Volga - Crop Region 17

PET A = 1193 May Daylength 12573 Latitude =48N PET I = 44247 July Daylength = 12826

Variable Deviation Normal Constant April May June July

Overall Constant 100 933175 926464 897282 894580 919142 Sep-Apr Prec (mm) Sep-Apr Prec (mm) Apr Mean Temp (oC) May Prec - PET (mm) May Prec - PET (mm) Jun Prec (mm) Jul Prec - PET (mn) Jul Prec - PET (mm)

DFN SDFN DFN DFN SDFN DFN DFN SDFN

26157 26157

936 -5792 -5792 4647

-11428 -11428

002714 000002 010724

002454 000010 041367 007652

-000016

002924 000014 038757 008253

-000034 -002531

003112 000018 030637 007940

-000008 -000874 -001664 -000089

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 338297

1144451

031240 296263 877718

059491 236683 560186

060645 238304 567888

067168 227791 518885

Standard Deviation of Yields = 338297 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Regions 10 and 17 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

BLACK SOIL ZONE SPRING WHEAT COVARIANCE MODEL

Region

West Black Soil Zone - Crop Region 11 East Black Soil Zone - Crop Region 12

PET A = 1021 June Daylength = 13600 Latitude 51ON PET I = 32810 July Daylength = 13170

Variable Deviation Normal Trend Februar May June July

Overall Constant 100 695206 754990 786415 901441 735854 660397 Linear Trend (1958-1971) 1400 080050 072078 067888 066978 076547 085523 Jan-Feb Avg Temp (0C) DFN -776 -021800 -025891 -042134 -039183 -047549 Apr Mean Temp (0O) DFN 660 024151 019529 028549 025310 May Prec (mm) DFN 4661 007030 006518 009128 May Prec (mm) SDFN 4661 -000242 -000167 -000183 Jun Prec PET (mm) DFN -6240 001118 001017 Jun Frec - PET (mm) SDFN -6240 000059 000074 Jul Frec - PET (mm) DFN -7754 -002477

R Squared 067730 070732 072231 083343 087270 088660 Standard Error (QHa) 231145 224490 223174 180531 165525 160285 Standard Variance (QHa) 534280 503958 498066 325915 273985 256914

Standard Deviation of Yields = 399291 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 11 and 12 SDFN = Squared Departure from Normal Yields Based on 1958-1971 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1971

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

ENTIHAL DISTRICT SPRING WHEAT MODEL

Region

Central District - Crop Region 13

Latitude - 560N

Variable Deviation Normal Trend April June August

Overall Constant 100 440233 519195 578767 553506 Linear Trend (1958-1973) Apr Mean Temp (0C) Apr Mean Temp (0C)

DFN SDFN

1600 531 531

074424 072646 -004278 -018358

068813 010158

-013446

079917 002698

-013102 Jun Pree (mm) DFN 6306 003033 002720 Jun Prec (mm) SDFN 6306 -000075 -000079 Aug Prec (mm) DrN 6313 004753 Aug Prec (mm) SDFN 6313 -000180

R Squared 074121 078510 081250 088586 Standard Error (QHa) 216720 213312 218268 190394 Standard Variance (QHa) 469674 455020 476409 362500

Standard Deviation of Yields = 411566 QHa

DFN Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

VOLGA-VYATSK SPRING WHEAT MODEL

itegion

Volga-Vyatsk - Crop Region 14

PET A = 914 May Daylength = 13517 Latitude 56 N PET I = 25737 June Daylength = 14448

Variable Deviation Normal Trend April May June

Overall Constant 100 480093 266753 367734 405194 Linear Trend (1958-1973) 1600 061530 086628 082821 080001 Sep-Apr Prec (mm) DFN 31744 -002538 -002706 -002086 May Prec - PET (mm) DFN -3941 002670 002393 May Pree -PET (mm) SDFN -3941 -000119 -000125 Jun Prec - PET (mm) DFN -5599 002452 Jun Pree - PET (mm) SDFN -5599 -000013

R Squared 063230 070384 079482 081666 Standard Error (QHa) 231232 215357 194864 203646

Standard Variance (QHa) 534684 463785 379718 414717

Standard Deviation of Yields = 368399 QHa

DFN = Departure from Normal Yields Based on 1958-1973 SDFN Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

- May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

UPPER VOLGA SPRMM WHEAT MODEL

Region

Upper Volga - Crop Region 15

PET A = 965 July Daylength = 13573 Latitude = 540N =rET I 29088

Variable Deviation Normal Trend April July

Overall Constant 100 731689 537479 641439 Linear Trend (1958-1971) 1400 067783 093677 073847 Sep-Apr Prec (mm) DFN 28350 -002527 -002242 Jul Prec - PET (mm) DFN -7923 005480 Jul Prec - PET (mm) SDFN -7923 000097

R Squared 070224 082836 091394 Standard Error (QHa) 192183 152398 119300 Standard Variance (QHa) 369342 232253 142324

Standard Deviationof Yields = 338375 QHa DFN Departure from Normal Yields Based on 1958-1971

SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

MIDDLE VOLGA SPRING WHEAT MODEL

Region

Middle Volga - Crop Region 16

PET A = 1058 June Daylength = 13748 Latitude 520N PET I 35238 July Daylength = 13296

Variable Deviation Normal Constant April June July

Overall Constant 100 982458 982458 982458 982458 Sep-Apr Pree (nn) DFN 26993 002395 002296 002006 Jun Prec - PET (mm) DFN -7604 005673 005150 Jul Pree - PET (mm) DFN -9344 002358

R Squared 000000 042909 062026 068602 Standard Error (QHa) 241340 189799 161676 154188 Standard Variance (QHa) 582449 360236 261392 237740

degStandard Deviation of Yields = 241340 QHa

DFN Departure from Normal Yields Based on 1958-1971 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1971 Yields Measured in Quintals per Hectare

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

NORTHWEST URALS SPRING WHEAT MODEL

Region

Northwest Urals - Crop Region 18

PET A = 874 April Daylength = 1882 Latitude = 580N PET I = 23120 May Daylength 13834

June Daylength = 14885

Variable Deviation Normal Trend April May June

Overall Constant 100 624429 818627 778111 813741 Linear Trend (1958-1973) 1600 027531 004685 009451 009651 Apr Prec - PET (mm) DEN 839 009554 009193 006438 Apr Mean Temp (SC) DFN 287 093806 078612 053556 May Prec - PET (mm) DEN -4475 -001376 -002616 Jun Prec - PET (mm) DFN -6152 004317 Jun Prec - PET (mm) SDrN -6152 -000040

R Squared 031130 056019 057666 076002 Standard Error (QHa) 201803 174188 178494 148573 Standard Variance (QHa) 407246 303414 318602 220739

Standard Deviation of Yields = 241340 QHa

DIN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

SOUTHERN URALSrWESTERN KAZAKHSTAN SPRING WHEAT COVARIANCE MODEL

Region

Southern Urals - Crop Region 19 Western Kazakhstan - Crop Region 21

0 PET A = 1076 May Daylength = 14010 Latitude = 59 N PET I = 36473 June Daylength = 15135

Crop Region 21 Constant = 1 if Data from Crop Region 21 Otherwise 0

Variable Deviation Normal Constant April May June July

Overall Constant 100 114404 1050547 1065578 1075772 1013858 Crop Region 21 Constant Nov-Apr Prec (mm) Nov-Apr Pree (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jul Mean Temp (degC)

DFN SDFN DFN DYN DEN

100 14194 14194 -7382

-10597 2173

-435112 -290132 004463 000008

-320907 004705 000006

-001246

-262653 003239

-000012 -002435 005190

-183449 003203

-000003 shy002567 002902

-066473

R Squared Standard Error (QHa) Standard Variance (QHa)

030510 328612

1079856

056484 272145 740627

056877 277604 770642

063295 262769 690474

071302 238715 569849

Standard Deviation of Yields = 385906 QHa

DFN Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 19 and 21 SDFN = Squared Departure from Normal Yields Based on 1958-1973 1962-1964 1969-1970 and 1972-1973 Yields Measured in Quintals per Hectare Missing for Western Kazakhstan

Meteorological Normals Based on 1958-1973

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

NORTHEASTERN URALS SPRING WHEAT MODEL

Region

Northeastern Urals - Crop Region 20

PET A = 898 June Daylength = 14448 Latitude 560N PET I = 24720

Variable Deviation Normal Trend April June August

Overall Constant 100 937018 997322 1272468 1268680 Linear Trend (1958-1973) 1600 042498 035404 003033 003479 Apr Pree (mm) DFN 2356 008081 000936 001663 Jun Prec - PET (mm) DEN -6288 009048 010930 Aug Prec (mm) DFN 5588 -005692

R Squared 031550 038293 066771 076703 Standard Error (QHa) 308486 303954 232156 203031 Standard Variance (QHa) 951633 923880 538965 412215

Standard Deviation of Yields = 360219 QHa

DEN = Departure from Normal Yields Based on 1958-1973 SDFN = Squared Departure from Normal Meteorological Normals Based on 1958-1973 Yields Measured in Quintals per Hectare

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

NORTHEAST KAZAKH SPRING-WHEAT COVARIANCE MODEL

Region

Kunstanay - Crop Region 22 Tsslinograd - Crop Region 23 Northern Kazakhstan - Crop Region 24 Pavlodar - Crop Region 25

PET A = 987 May Daylength - 13113 Latitude = 53degN PET I = 30533 June Daylength = 13906

July Daylength = 13431

Crop Region 24 Constant = 1 if Data from Crop Region 24 Otherwise 0

Variable Deviation Normal Constant April May June Jul

Overall Constant 100 739502 760706 765250 793874 934027 Crop Region 24 Constant Apr Mean Temp (0C) May Prec - PET (mm) Jun Prec - PET (mm) Jul Prec - PET (mm) Jul Mean Temp (0C)

DFN DFN DFN SDFN DITN

100 406

-5555 -9426 -8595 2031

210275 176968 -045418

169216 -012129 004311

143237 -023457 002434 007773

080349 -050309 002165 007456

-000127 -051645

R Squared 009543 020096 032184 052166 072607 Standard Error (QHa) 288452 275181 257445 219674 171874 Standard Variance (QHa) 832046 757247 662778 482567 295407

Standard Deviation of Yields = 298922 QHa

DFN = Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 22 23 24 and 25 SDFN Squared Departure from Normal Yields Based on 1958-1961 1965-1968 1971

19 58 19 71 Yields Measured in Quintals per Hectare Meteorological Normals Based on r

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

SIBERIA-ALTAI SPRING W EAT COVARIANCE MODEL

Region

West Siberia - Crop Region 26 Altai Krai - Crop Region 27

0 PET A = 922 May Daylength = 13517 Latitude = 56 N PET I = 26232 June Daylength = 14448

July Daylength = 13887

Crop Region 26 Constant = 1 if Data from Crop Region 26 Otherwise 0

Variable Deviation Normal Constant March April May June July August

Overall Constant 100 1036206 1014462 1072857 1246659 1169695 1312888 1323614 Crop Region 26 Constant 100 -050450 -006966 -014280 -165014 -166298 -235021 -217003 Sep-Mar Pree (mm) DFN 19333 003362 -000437 -000827 -002072 -001831 -001377 Apr Prec (mm) DEN 2597 022124 014560 012189 008049 010557 Apr Prec (mm) SDFN 2597 -000446 -000514 -000382 -000480 000526 May Prec - PET (mm) DEN -4988 005790 004042 004680 005530 May Prec - PET (mm) SDFN -4988 -000106 -000034 -000049 -000036 Jun Prec - PET (mm) DFN -7445 006239 007056 007219 Jul Pree - PET (mm) SDFN -7885 -000064 -000084 Aug Prec (mm) DFN 5377 -005937

R Squared 000447 010830 042824 056393 068148 072495 080402 Standard Error (QHa) 389871 375750 312686 284698 248789 236630 204675 Standard Variance (QHa) 1519996 1411882 977723 810532 618958 559937 418919

Standard Deviation of Yields 383949 (QHa)

DFN= Departure from Normal Yields and Climatic Data are Pooled Over Crop Regions 26 and 27 SDFN = Squared Departure from Normal Yields Based on 1958-1972 Yields Measured in Quintals per Hectare Meteorological Normals Based on 1958-1972

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

SOUTH KAZAKHSTAN SPRING WHEAT MODEL

Region

South Kazakhstan - Crop Region 29

PET A = 1015

PET I = 32393 June Daylength = 13460 July Daylength = 13049

Latitude =50N

Variable Deviation Normal Constant April May June July August

Overall Constant Sep-Apr Prec (mm) May Temp (oC) Jun Prec - PET (mm) Jul Pree - PET (mm) Aug Prec (mm)

DFN DFN DrN DFN DFN

100 17012 1319

-9493 -9729 3261

820883 822386 003913

835113 004524

-062806

809219 006256

-021515 010224

807708 006507

-017299 010043 000757

788205 005346

-018741 009599 000658 -005057

R Squared Standard Error (QHa) Standard Variance (QHa)

000000 279059 778739

021318 256877 659859

055796 200400 401602

078559 145777 212510

079261 150366 226098

081376 150203 225608

Standard Deviation of Yields = 279059 QHa

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1971-1974 Meteorological No~mals Based on 1957-1974

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

CENTRAL ASIA SPRING WHEAT MODEL

Region

Central Asia - Crop Region 30

PET A = PET I =

1421 59091

April Daylength = 10977 May Daylength 11921 June Daylength = 12373

Latitude = 400N

Variable Deviation Normal Constant April May June July

Overall Constant Apr Prec - PET (mm) Apr Prec - PET (mm) May Prec - PET (mm) May Prec - PET (mm) Jun Prec - PET (mm) Jun Pree - PET (mm) Jul Temp (oC)

DFN SDFN DFN SDFN DFN SDFN DEN

100 2417 2417

-5230 -5230

-12127 -12127

2594

585231 633719 001504

-000040

678623 000626

-000040 001943

-000044

744896 000780

-000050 001957

-000061 -000686 -000179

743362 000821

-000049 001872

-000060 -000755 -000178 -006632

R SquaredStandard Error (QHa)

Standard Variance (QHa)

000000 117600

138298

028803 106080

112530

062768 082858

068654

083811 059852 035823

084042 062638 039236

Standard Deviation of Yields = 117600 QHa

DFN = Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1974 Meteorological Normals Based on 1958-1974

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

EASTERN SIBERIA SPRING WHEAT MODEL

Region

Eastern Siberia - Crop Region 31

PET A = 906 June Daylength = 13906 Latitude =53 N PET I = 25181

Variable Deviation Normal Trend May June July August

Overall Constant 100 921112 932541 1017852 1023747 968920 Linear Trend (1958-1972) 1500 026451 025022 014358 013621 020475 Mar-Say Prec (mm) DFN 6873 001594 002380 002315 002714 Jun Pree - PET (mm) DFN -6808 007714 005760 006060 Jul Temp (0C) DFN 1912 -044442 -012261 Aug Pree (mm) DFN 6080 -003368

R Squared 027949 030623 071120 076052 085004 Standard Error (QHa) 197101 201307 135656 129562 108070 Standard Variance (QHa) 388489 405244 184026 167863 116790

Standard Deviation of Yields = 223757 QHa

DFN = Departure from Normal Yields Based on 1958-1972 SDFN = Squared Departure from Normal Meteorological Normal Based on 1958-1972 Yields Measured in Quintals per Hectare

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

FAR EAST SPRING WHEAT MODEL

Region

Far East - Crop Region 32

PET A = 997 June Daylength m 13460 Latitude = 500N PET I = 31201 July Daylength = 13049

Variable Deviation Normal Trend May June July September

Overall Constant Linear Trend (1958-1972) May Temp (0C) Jun Prec - PET (mm) Jun Free - PET (mm) Jul Pree - PET (mm) Sep Pree (mm)

DFN DFN SDFN DFN DFN

100 1500 1148

-3137 -3137 -1188 7607

547145 037941

599671 029597 076039

647163 033527 048272 001584

-000025

660890 036973 008222 001990

-000037 000946

675554 042602

-085102 002472

-000052 002187

-002711

LA R SquaredStandard Error (QHa) Standard Variance (QHa)

053412 165844

275042

062298 155826

242818

077856 132027

174312

079712 134037

179658

086153 118379

140136

Standard Deviation of Yields = 233443 Q1a

DFN Departure from Normal SDFN = Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1968 and 1970-1972 Meteorological Normals Based on 1958-1972 for One Station -

Blagoveschesk

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977

NORTHWEST SPRING WHEAT MODEL

Region

Northwest - Crop Region 33

PET A = 897 June Daylength = 14885 Latitude = 58degN FET I = 24646

Variable Deviation Normal Trend April June July

Overall Constant Linear Trend (1958-1972) Apr Pree (mm) Jun Pree - PET (mm) Jun Prec - PET (mm) Jul Temp (0C)

DFN DFN SDFN DFN

100 1500 3480

-6610 -6610 1757

441524 046762

448170 045829 000461

513108 045822 001411 001664

-000059

518313 045239 001182 001306

-000059 -016707

LA

R Squared Standard Error (QHa) Standard Variance (QHa)

064011 157275 247355

064068 164139 269414

069258 167847 281725

070450 174541 304646

Standard Deviation of Yields = 251880 QHa

DEN = Departure from Normal SDFN Squared Departure from Normal Yields Measured in Quintals per Hectare

Yields Based on 1958-1970 and 1972 Meteorological Normals Based on 1958-1972

NASA-JSC

May 1977