Aridity in Telangana Region: An Analysis of Drought

IRJMSH Vol 6 Issue 5 [Year 2015] ISSN 2277 – 9809 (0nline) 2348–9359 (Print)

International Research Journal of Management Sociology & Humanity ( IRJMSH ) Page 55

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Aridity in Telangana Region: An Analysis of Drought

Satyendra Singh Narwaria

Ritesh Ranjan Pushkar1

Introduction

Drought can be termed as a temporary reduction in water or moisture availability

significantly below the normal amount for a specific period. However, it can be said that

drought is a term which is very difficult to be defined precisely. It embraces a phenomenon

which is very diverse and complex.

There has been no universally acceptable definition of drought. However most of the

definitions of drought may be categorized in:

Meteorological definitions: These are the most common definitions of drought,

which usually compare precipitation levels to a long term average. Meteorological

drought refers to a specific degree of dryness for a given duration.

Hydrological drought: These definitions focus on the surface and sub-surface water.

Usually these studies aim at unraveling the relationship between meteorological

drought and water supply.

Agricultural drought: These definitions include the emphasis on deficits in meeting

the crop water needs. These definitions are relatively more important in rained

agricultural systems.

Socio-economic drought: It includes those definitions of drought, which highlight

the effects of water shortage on human society and economy. These definitions are

very rarely used.

All these four categories of drought definitions point towards the same phenomenon i.e.

shortage in precipitation which leads to water shortage.

It is quite interesting to note that any area at any point of time may or may not experience the

drought of more than one type. E.g. an area may not be having hydrological drought in spite

of having meteorological drought. This is because of the higher than the normal precipitation

may have occurred in previous terms.

Similarly, a region may not have agricultural drought in spite of having meteorological

1 Satyendra and Ritesh are the Ph.D scholars in Centre for the South Asian Studies in School of International Studies

and in Centre for the Studies of Regional Development in School of Social Sciences respectively of Jawaharlal

Nehru University, New Delhi-110067



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drought. This may be because of the well-developed agricultural systems.

Operational definition of drought: Drought is a region occurs when there is less than 20%

Of the total rainfall received in a particular period.

Criteria will be: (as per IMD)

Variability in rainfall (%) Condition

< -50.00 % Severe drought

-25.00 - 50.00 % Deficit rainfall

- 19.00 - 19.00 % Normal Departure

19.00 – 50.00 % Excess rainfall

>50.00 Extreme / Flood condition

About Telangana: Telangana region is the interior part of the state of Andhra Pradesh. Of the three regions of

the state, Telangana has the largest area, with 1,14,800 km².The Telangana plateau is

composed of Archean Gneissic rocks and drained by Godavari and Krishna rivers. The entire

region is divided into two main regions namely Ghats and pen plains. The surface is dotted

with low depressions.

The region lies on the Deccan plateau to the west of the Eastern Ghats range, and includes the

northwestern interior districts of Warangal, Adilabad, Khammam, Mahabubnagar, Nalgonda,

Rangareddy, Karimnagar, Nizamabad, Medak, and the state capital, Hyderabad. The Krishna

and Godavari rivers flow through the region from west to east.

Statement of the problem: Drought is one of those concepts which have the highest

relevance in today’s age of global warming. For the present study, meteorological drought of

the Telangana region will be studied.

Objectives: Following objectives have been formulated:

I. To study the annual rainfall variability of various meteorological stations in

Telangana region.

II. To study the monthly rainfall variability of various meteorological station in

http://en.wikipedia.org/wiki/Andhra_Pradesh

http://en.wikipedia.org/wiki/Archean

http://en.wikipedia.org/wiki/Godavari_River

http://en.wikipedia.org/wiki/Krishna

http://en.wikipedia.org/wiki/Deccan

http://en.wikipedia.org/wiki/Eastern_Ghats

http://en.wikipedia.org/wiki/Warangal

http://en.wikipedia.org/wiki/Khammam

http://en.wikipedia.org/wiki/Mahabubnagar



http://en.wikipedia.org/wiki/Nizamabad

http://en.wikipedia.org/wiki/Medak

http://en.wikipedia.org/wiki/Hyderabad,_India

http://en.wikipedia.org/wiki/Krishna_River

http://en.wikipedia.org/wiki/Godavari_River



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Telangana region.

III. To study the trend of occurrence of drought in various meteorological stations.

IV. To study the annual probability of the occurrence of Drought in various

meteorological stations.

V. To study the monthly probability of the occurrence of Drought in various

meteorological stations.

Database:

Daily weather reports of the Indian Meteorological Department (IMD) Year: 1982-2007

Methodology:

Following steps have been taken in the analysis of data:

Col lec t ion of data: the data of ACTUAL RAINFAL & NORMAL RAINFALL has been

taken.

Calcula t ion of the deviation:

(i) Deviation = Actual data – normal data

(ii) % deviation =( deviation/normal data)* 100Then the data has been categorized into

various meteorological conditions like drought, normal and excess rainfall.

P robabi l i ty of occurrence of drought conditions has been calculated by dividing

t h e no of drought years, months by number of normal rainfall of that particular

month, day.

Literature review:

Gregory, S (1985) attempted to study the change in frequency of drought of India for a

period of 115 years (1871-1985). He emphasized the vital role of summer monsoon rainfall

(mainly in the four months June to September inclusive). While doing literature review he

found that throughout all the literature, the occurrence of individual drought years, or

successive years of low rainfall, has always been noted and commented upon.

He faced the difficulties in : (i) the changing definition of drought or significant rainfall

deficit, (ii) changes in the space units considered, from individual stations to subdivisions,

macro-regions or All-India.

He used the database provided by various scholars who studied thae rainfall in India

previously.



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The purpose of his paper was to examine the extent to which drought frequency has changed

over and within the period 1871-1985, and the differences in such changes from one part of

India to another.

He divided India into 10 major regions with 29 meteorological substations and 306 District

stations. His regions were: Region 1: Assam Region 2: Northern West Bengal and Bihar

Region 3: Southern West Bengal and Bihar Region 4: North-East Peninsula Region 5: Uttar

Pradesh Region 6: The North-West Region 7: Gujarat, Saurashtra and Kutch Region 8:

North-West and North-Centre Peninsula Region 9: South-East Peninsula Region 10: South-

West Peninsula

In each case, droughts were seen as occurring in a region under the following circumstances:

(i) the driest ten per cent of years, i.e. the driest 11 years in any region; (ii) years in which the

Summer monsoon rainfall deficit was more than 20 per cent i.e. rainfall was less than 80 per

cent of the 1871-1985 average. (iii) Years in which much bigger deficits occurred, this

applying to only some of the regions.

And finally he presented the findings based on the above mentioned criterions.

Skaggs, Richard H. (1975) studied the Drought in the United States, 1931-40. He used the

palmer index of meteorological drought as the measure of dryness (and wetness). The palmer

index is a normalized measure of intensity of dryness or wetness over an area.

The values may be compared directly between locations and through time. The palmer index

ranges from greater than 4.00 for extremely wet condition to less than -4.00 for extreme

drought. A value of zero indicates normal moisture conditions. He calculated the palmer Index

for monthly periods of climatologically divisions. He calculated the index on a regular basis for

all climatological divisions of the United States since January 1931. Then he analyses the data

using various complex mathematical series.

He found that 1931-40 period was dry on a national scale. The northern Rocky Mountains, the

northern plains, and the central plains were the major drought area and experienced the most

intense and longest drought. The most intense drought was found to be occurred in 1933-34,

1936 and 1939-40.

Radcliffe, Miles, Rydz and Shaw (1978) studied the meteorological Aspects of the 1975-76

droughts in Western Europe. other than the meteorology, they included a few facts about

evaporation during the period, drawn attention to some associations and possible feedback

mechanisms involving the atmosphere, oceans and ice cover which might have contributed to

its onset and maintenance and also made an attempt to put the drought in a historical

perspective.

Their methodology was linked to getting the facts from the reviews of the related literatures

and other meteorological data available from laboratories e.g. Synoptic Climatology Branch.

Then they have given a clarification about the causes of this drought. They provided the

description of drought. They defined drought as occurring over the 16 month period May 1975



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to August 1976 inclusive.

Over England and Wales as a whole the 16 month period had about 10 % less rain than was

recorded over any other 16 month period since 1820 and that was without doubt the driest

such period since records began in 1727. The severest drought was in central southern

England and northern France but much of Europe was affected to some extent. They focused

their study to the rainfall events of England and Wales as a whole.

They added meteorological description to the drought. Firstly, in addition to their dryness,

the winters 1971-4 were all mild, not only in Britain but over most of Europe as far east as

Moscow and also in the Russian Arctic. As a result, the coldest air in the Northern

Hemisphere was displaced west- wards to Canada and the North Pacific, where winters were

all notably colder than the 1951-70 averages.

The second interesting fact was that the jet stream in the east Atlantic/European sector was

displaced between 5 and 10 degrees of latitude northwards over the 16 month drought period

compared with the same 1951-70 averaging period. This northward movement occurred in

the late autumn of 1974 and, on a monthly basis, was persistent, with only short period

variations until September 1976, suggesting a good deal of inertia in the atmosphere over this

16 month period.

Thirdly, they not iced t h a t the Pacific Ocean north of 40o

N was continuously colder than

usual, especially from spring 1975 to summer 1976 inclusive. It is probable that the coldness

of the ocean was partly due to the coldness of the winters of the early 1970s in that sector of

the hemisphere: in particular, ice was excessive in the North Pacific in late winter 1975 and

1976, and its melting may well have been partly responsible for the sharp increase of negative

sea tempera- true anomalies in the springs and summers of those years.

They concluded that: (i) The drought was the result of complicated interaction between a

number of large-scale meteorological and oceanographic factors. (ii) Feedback mechanisms

involving ocean temperatures in the Atlantic and Pacific and also the dryness of the ground

itself probably helped to maintain the atmospheric mode longer than it otherwise would have

done. (iii) There appears no evidence to suggest a climatic change or trend; rather the drought

stands out as an isolated but very unusual event. (iv) The enhanced Pacific flow and the

winter coldness over Canada appear to have been important factors in the drought.

INTERPRETATTIONS:

1.1 frequency of drought (annual)

From sheet-1, we can say that almost all the districts are having more or less

prevalence of rainfall deficiency. As we can say that every district is experiencing drought

condition. However Khammam, Ramagundam and Mehboob nagar are having frequent

occurrence of drought condition. Here Mehboob nagar is the worstly affected

meteorological station in the region, where drought condition has prevailed in more than

50% of the years under study. However Hyderabad and Nizamabad are least affected

meteorological stations with 2 and 4 times of occurrence of drought in past 26 years

respectively.



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The number of drought years in past 26 years may be summarized as :

TABLE - I

Meteorological station No. Of drought years

Hanamkomda 6

Hyderabad 2

Khammam 7

Mehboonagar 14

Nizamabad 4

Ramagundam 7

Now the monthly rainfall variability of the various stations in the telangana region may

be studied with the help of sheet-2

1.2 frequency of drought (monthly)

Hanamkonda : Hanamkonda is a moderate drought prone region which has 6

times occurrence of drought in past 26 years. The monthly analysis of the data

reveals theVulnerability of the Hanamkonda district towards drought. Here every month in

one or other year is experiencing the drought condition. However the months having

less amount of normal monthly rainfall (winter months) are worstly affected. This is

because that even a minor change in the received rainfall may cause very high percent of the

rainfall variability in the meteorological station. February and august are the least drought

prone months. The monthly table of the rainfall variability of Hanamkonda is:

TABLE-II (HANAMKONDA)

MONTH OCCURENCE OF DROUGHT IN

PAST

26 YEARS ( 1982-2007) JAN 18

FEB 5

MAR 18

APR 19

MAY 16

JUN 19

JUL 11

AUG 9

SEP 13

OCT 12

NOV 15

DEC 20



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Hyderabad: Hyderabad is one of the least drought prone districts of the telangana region. So

monthly analysis of the data is required, so as to know the months which are vulnerable to

the drought condition. Hyderabad is also the more droughts prone in case of low rainfall

month’s .i.e. winter season.

Khammam: this is the most vulnerable meteorological station to the drought conditions. If

we see the monthly occurrence of the rainfall in this region then it can be interpreted that this

station has recorded the highest variability in rainfall received. It has drought condition in

case of December month in 22 out of 26 years under study. Number of drought years is also

very high in case of the rainy season months.

(HYDERABAD)

MONTH OCCURENCE OF DROUGHT IN PAST 26

YEARS ( 1982-2007)

JAN 16

FEB 19

MAR 15

APR 13

MAY 18

JUN 8

JUL 10

AUG 5

SEP 17

OCT 10

NOV 13

DEC 18

TABLE-IV

(KHAMMAM) MONTH OCCURENCE OF DROUGHT IN PAST 26

YEARS ( 1982-2007)

JAN 15

FEB 7

MAR 21

APR 19

MAY 18

JUN 18

JUL 12

AUG 4

SEP 16

OCT 18

NOV 19

DEC 22



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Mehboob nagar: comparatively this station also records high chances of drought months in

case of winter months like November, December, January, and February. It has recorded

highest occurrence of drought in May, where it has drought in 23 out of 26 years under

study.

Table V

(MEHBOOBNAGAR)


YEARS ( 1982-2007)

JAN 21

FEB 17

MAR 13

APR 17

MAY 23

JUN 11

JUL 8

AUG 16

SEP 15

OCT 14

NOV 18

DEC 19

Nizamabad : This station behaves like Hyderabad in one or other way. This station also

records relatively lesser number of drought years as comparable to other stations. However

there is a strange finding that this region has recorded about 25 times drought situation out

of 26 years under study in May month.

TABLE-VI (NIZAMABAD)


YEARS ( 1982-2007)

JAN 18

FEB 15

MAR 17

APR 12

MAY 14

JUN 25

JUL 10

AUG 11

SEP 13

OCT 10

NOV 17

DEC 14



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Ramagundam: This station has received the least number of drought months in the

month of May, where it has recorded only 2 months under drought situation in past 26

years. However similar to Nizamabad station this station has also received highest

frequency of drought occurrence in the month of May , where it has recorded 24 years of

drought out of 26 years under study. TABLE-VII

(RAMAGUNDAM)

MONTH OCCURENCE OF DROUGHT IN PAST

26

YEARS ( 1982-2007) JAN 17

FEB 16

MAR 16

APR 9

MAY 2

JUN 24

JUL 12

AUG 9

SEP 17

OCT 14

NOV 15

DEC 20

1.3 Probability of drought (annual) : probability of drought is a very difficult to be

calculated criteria. However for the present study it has been calculated the actual

occurrence of drought divided by total number of years under study.

TABLE – VIII PROBAILITY OF DROUGHT ( ANNUAL)

Meteorological station No. Of drought years Probability of drought

Hanamkomda 6 .23

Hyderabad 2 .08

Khammam 7 .27

Mehboonagar 14 .54

Nizamabad 4 .15

Ramagundam 7 .27

This table reveals that Mehboob nagar is the highest drought prone station of the region

with a probability of 0.54 for occurrence of drought. It is followed by the meteorological

stations of Khammam, Ramagundam and Hanamkonda with probabilities of 0.27, 0.27 and

0.23 Respectively. Hyderabad and Nizamabad are the meteorological stations with least

chances of occurrence of drought i.e. 0.08 and 0.15 probability respectively.



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1.4 Probability of drought (monthly): probability of occurrence of drought in various

months has been tabulated in table-IX.

TABLE – IX

PROBAILITY OF DROUGHT ( MONTHLY)

Hanamkonda

Hyderabad

Khammam

Mehboob

nagar

Nizamabad

Ramagundam

JAN 0.69 0.62 0.58 0.81 0.69 0.65

FEB 0.19 0.73 0.27 0.65 0.58 0.62

MAR 0.69 0.58 0.81 0.50 0.65 0.62

APR 0.73 0.50 0.73 0.65 0.46 0.35

MAY 0.62 0.69 0.69 0.88 0.54 0.08

JUN 0.73 0.31 0.69 0.42 0.96 0.92

JUL 0.42 0.38 0.46 0.31 0.38 0.46

AUG 0.35 0.19 0.15 0.62 0.42 0.35

SEP 0.50 0.65 0.62 0.58 0.50 0.65

OCT 0.46 0.38 0.69 0.54 0.38 0.54

NOV 0.58 0.50 0.73 0.69 0.65 0.58

DEC 0.77 0.69 0.85 0.73 0.54 0.77

This table-IX tells us about the probability of occurrence of drought in various months

at various meteorological stations. Here the highest probability of occurrence is there in

the month of June for the Nizamabad and Ramagundam. This very high occurrence of

drought in this month may be attributed to late onset of the SW monsoon.

Month of august is least affected month as far as the occurrence of drought is concerned.

Hyderabad and Khammam have probabilities of 0.19 and 0.15 of occurrence of drought in

the month of August respectively.

Findings:

Khammam, Ramagundam and Mehboob nagar are having frequent occurrence

of drought condition. Here Mehboob nagar is the worstly affected



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meteorological station in the region, where drought condition has prevailed

in more than 50% of the years under study. However Hyderabad and

Nizamabad are least affected meteorological stations in past 26 years with 2

and 4 times of occurrence of drought respectively.

However the months having less amount of normal monthly rainfall ( winter

months) are worstly affected. This is because that even a minor change in the

received rainfall may cause very high percent of the rainfall variability in the

meteorological station.

Month of August is least affected month as far as the occurrence of drought is

concerned.

Some meteorological stations in like Nizamabad and Ramagundam have very

high occurrence of drought in June month. It may be attributed to late onset

of the SW monsoon.

References:

M o r a l e s , Chorister (1977). Rainfall Variability: A Natural Phenomenon. Ambio,

Vol. 6, No.1, Water: A Special Issue (1977), pp. 30-33

G r e g o r y , S. (1989). The Changing Frequency of Drought in India, 1871-

1985 .The Geographical Journal, Vol. 155, No. 3 (Nov., 1989), pp. 322-33

B a g l a , Pallava. (2002). Drought Exposes Cracks in India's Monsoon Model.

Science, New Series, Vol. 297, No. 5585 (Aug. 23, 2002), pp. 1265-1267

R a n g a s w a m i , Amrita (1974). The Uses of ‘Drought’. Economic and Political

Weekly, Vol. 9, No. 50 (Dec. 14, 1974), pp. 2069+2071-2074

R at c l i f f e , Miles, Rydz and Shaw. (1978). Meteorological Aspects of the 1975-76

Drought [and Discussion] . Proceedings of the Royal Society of London. Series A,

Mathematical and Physical Sciences, Vol. 363, No. 1712 (Nov. 1, 1978), pp. 3-20

H u l m e , Mike (1990). The Changing Rainfall Resources of Sudan .Transactions of

theInstitute of British Geographers. New Series, Vol. 15, No. 1 (1990), pp. 21-34

Walsh, Hulme and Campbell. (1998). Recent Rainfall Changes and Their Impact on

Hydrology and Water Supply in the Semi- Arid Zone of the Sudan. The Geographical

Journal, Vol. 154, No. 2 (Jul., 1988), pp. 181-197

S k a g g s , Richard H. (1975). Drought in the United States , 1931-40. Annals

of the Association of American Geographers, Vol. 65, No. 3 (Sep., 1975), pp. 391-402

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Aridity in Telangana Region: An Analysis of Drought

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