Blue Earth 16Dec 2015
Crop
Weather Outlook
2017 & Beyond
• Before the Pyramids, people knew the sun appeared in different places according to season. The Moon too.
• But, for the Moon, it was 18.6 years after the Moon came up furthest North until it did it again.
Super Moon Flood Tide
•
Dr. Tiffany Troxler and correspondent David Begnaud in a street suffering from a “king tide” made worse by the supermoon. CBS NEWS
Chinook
Wind Shift With Season
Wind Shift with time of Day
Wind Shift with time of Day
2016 10 days of low wind in June
http://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=173&network=SD_ASOS&zstation=YKN&units=mph&_opt_p1=on&p1=0501-0510&_
Rain days per year have increased substantially
y = 0.0517x - 69.076
0
10
20
30
40
50
60
1880 1900 1920 1940 1960 1980 2000 2020
Ames, IA Precipitation by year 1893-2007
100+ yr Precipitation, 20%+ increase
1950-1993 Precipitation
Most of the United States experienced significant precipitation increase. Diminished Tropical Storms impacted Florida.
Heavy rain events are more common?
Increased River Flow (NE Iowa)
y = 6.932x - 12627
0
500
1000
1500
2000
2500
3000
3500
1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 2020
Turkey River at Garber, IA
6-fold increase of Flood Prone Years
2-fold increase in annual river flow
Kishwaukee @ DeKalb
y = 18.825x - 35716
0
1000
2000
3000
4000
5000
6000
1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
mea
n an
nual
cfs
Year
Nishnabotna @Hamburg, IAhttp://nwis.waterdata.usgs.gov/ia/nwis/annual
(SW Iowa)
2-fold increase in annual river flow
6-fold increase of Flood Prone Years
stable period 2 stable period 3 stable period 4
137
Beyond
History Forecast
Farmer Benner in 1885 noted dry/wet cycle. Dust Bowl
1992-2004
Periodic Impacts IA Corn
020406080
100120140160180
1900 1920 1940 1960 1980 2000
Year
Bu/
aIA Corn1-in-3 chance of drought
vs 1-in-12 or 13
Farmer Benner
•
On the average drought has a an 18.6 yr. period.
2012
Weather Volatility
Climate RISK in Agriculture is likely to be greater during the next 20 years Management of RISK is of increasing importance
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/season.JFM.nao.gif
Gleissberg
19 yr Dry/Wet Tree rings indicate climate cycles.
wet
dry
Heat & Water Stress
& 90 year cycles
Tree Rings Roanoke, NC cypress tree. Dennis Blanton, Wm & Mary College, David Stahle, Univ. of Arkansas.
U.S. drought starts here.
800 Year Rain (Virginia)
La Nina : Extremes
How to Evaluate the Crop Year
Part 1: Knowing the Yield Trend
http://yourweatherservice.com/
http://yourweatherservice.com/
Annual precipitation 27.64 inch
•
NOTE
•
mygeohub.org/groups/u2u/acv
•
mygeohub.org/groups/u2u/acv
•
mygeohub.org/groups/u2u/acv
•
Webster County IA
• What changed: 2011, 2012, 2013, 2014? • Were 1999 & 2000 identical?
•
•
• The USDA yield estimate is based on : – Crop Development – Crop Condition – Some factors that influence yield do not
show up in the estimate considerations. • Growing Degree Days, Heat Stress, Relative
Precipitation
mygeohub.org/groups/u2u/acv
M
flood
X
X
X
2009 High Yield SE SD 2011 Low Yield SE SD
http://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=32&network=SDCLIMATE&station=SDC009&year=2011&var=low&dpi=100&_fmt=png
• mesonet.agron.iastate.edu/plotting/auto/?q=32
•
mesonet.agron.iastate.edu/plotting/auto/?q=108
•
mesonet.agron.iastate.edu/plotting/auto/?q=108
Flood Low Big
Flood Low Big
Flood Low Big
Low Low High
Low Low High
Low Low High
High High Low
High High Low
High High Low
Elwynn Taylor Iowa State University
Climatologist
END
WWW.twitter.com/elwynntaylor [email protected]
County Yield Trend and My Yield Trend
• 30-year trend for Corn and Soy is publically available for the Nation, state, and most Corn belt counties.
• Graphs, interactive graphs, and data sets are available at: mygeohub.org/groups/u2u/acv
• Expand the map to find your county and click on any “red” spot shown in the county (a few counties do not have yield trend, so use one adjacent to the original choice).
• After locating the county of interest, click on any red spot and then click “Select this station” then select “Yield Trend.”
• See the 30-year trend with yearly yields and options to see the numerical values for yield and yield trend. (you will later compute the % deviation from the trend for chosen years.)
Know the yield record for your farm and for your county.
•
The bushel per acre yield is important, but the “Time Trend” is essential to the evaluation of the crop success (or failure). Do not judge a crop by the Bushel yield as compared to yields of a few years past. Yields over time are best evaluated by comparative “percent of trend.” First get your county yield history. The trend is ideally determined from a 30-year record. County yield records (displayed as a graph or as a data sheet) are available from “mygeohub…” a website produced by a consortium of extension across the Midwest. Second compile the history and trend of the fields or farms you operate. Do not despair because you record is less than 30 years, use the records you have. Most accomplish this using Microsoft Excel or the equivalent. Should you not have the spreadsheet program or are less than comfortable operating it I suggest employing a 12-yr old in this project (if your local youth refuses, ask for a suggested computer geek he/she knows). The Excel program will plot yields according to year and insert a trend line, equation of the trend line, and compute what the trend yield is for each year. You can have it display the yield as a percent of trend for any chosen year or years. A yield that is 90% (or less) of the trend legally a drought. It is useful to take note of yield as a percent of trend for the evaluation of “Good,