Climate Variability and Climate Change: Decision Making under Uncertainty

Gerrit HoogenboomDirector, AgWeatherNet &

Professor of AgrometeorologyWashington State University, USA

AgMIP–Pakistan Kickoff Workshop &International Seminar on Climate Change

University of Agriculture Faisalabad, PakistanJune 4-6, 2013

4,000 km

Winter OutlookWeather and Agriculture

• Weather has an important impact on agriculture, both crop and animal production.

• For dryland agriculture more than 90% of the variability in yield can be explained by weather conditions.

Winter OutlookClimate and Weather

• Does a farmer have options to modify or change his production system?

• If so, what are these options?• Can weather and climate information play a

role?• How do we provide this information?

National Weather Service

• Cooperative Weather Station Network– Volunteer data collection network– Limited set of data (temperature and rainfall)– Approximately 85 stations in Georgia– Long-term records– Data collected at Griffin Experiment Station since 1926

Georgia Automated Environmental Monitoring Network

First weather station was installed in 1991

Air temperature, rainfall, relative humidity, wind speed and direction, solar radiation, soil moisture

Georgia Automated Environmental Monitoring Network

Weather StationWeather Station

Web ServerWeb Server

SatelliteSatellite

FTP FTP

TransferTransfer

Weather ServerWeather Server

InternetInternet

Current ConditionsCurrent Conditions

Climate DataClimate Data

Water BalanceWater Balance

Crop ModelingCrop Modeling

www.Georgiaweather.net

Winter OutlookWind Machines & Frost

Weather Data and Applications

Climate in the southeastern USAWhy should farmers care?

Climate Variability and Climate Change

Climate Variability2-3 months

Inter-annual

Decadal

Climate ChangeSeveral decades

50+ years

Centuries

Changing Ocean Temperatures

Impacts the climateacross the globe

El Niño and La Niña• El Niño: above-average

sea-surface temperatures that develop across the east-central equatorial Pacific.

• La Niña: cold phase

Why are El Niño and La Niña important?

Effects of El Niño

Why are El Niño and La Niña important?

Effects of La Niña

El Niño, La Niña and Neutral Phases

Climate in the southeastern USAWhy should farmers care?

Deviation From the Mean

-80

-60

-40

-20

0

20

40

60

80

NEUTRAL LA NINA EL NINO

De

via

tion

fro

m m

ea

n s

eve

rity

(%

)

Field observations (188 fields, 5 seasons)

ENSO and Tomato Spotted Wilt Virus (TSWV) severity in peanut

a b

* Courtesy of Dr. D. Riley, UGA

(a). Leaf symptoms of TSWV on peanut (b). Western Flower Thrips (vector)

Farmers and Climate: Why models?

• Traditional agronomic approach:– Experimental trial and error

• Systems Approach– Computer models– Experimental data

• Understand Predict Control & Manage– (H. Nix, 1983)

• Options for adaptive management and risk reduction

Soil Conditions Weather data

Model Model

Simulation Simulation

Crop Management Genetics

GrowthGrowth DevelopmentDevelopment

YieldYield

Soil Conditions Weather data

Model Model

Simulation Simulation

Crop Management Genetics

GrowthGrowth DevelopmentDevelopment

YieldYield

Net IncomeNet IncomePollutionPollution Resource UseResource Use

Linkage Between Data and Simulations

Model credibility and evaluation Input data needs:

Weather and soil dataCrop ManagementSpecific crop and cultivar informationEconomic data

Observed Yield vs. Rainfall (mm/d)

0

500

1000

1500

2000

2500

3000

3500

4000

0 2 4 6 8

Rainfall (mm/d)

Yie

ld (

kg/h

a)

Simulated Yield vs. Rainfall (mm/d)

0

500

1000

1500

2000

2500

3000

3500

4000

0 2 4 6 8

Rainfall (mm/d)

Yie

ld (

kg/h

a)

Observed and simulated soybean yield as a function of seasonal average rainfall (Georgia

yield trials)

Observed Yields

0500

1000150020002500300035004000

25 27 29 31 33

Max Temp Average (C)

Yie

ld (

kg/h

a)

Simulated Yields

0500

100015002000

2500300035004000

25 27 29 31 33

Max Temp Average (C)

Yie

ld (

kg/h

a)

Observed and simulated soybean yield as a function of average max temperature

(Georgia yield trials)

• Three representative soil profiles for each county• Soil surface data• Soil horizons

• Crop management options:– Crop selection– Variety selection– Planting date– Irrigated versus rainfed– Fertilizer applications

• Prices and production costs

Spatial DataAlabama, Florida and Georgia

Simulations: Cotton Yield Variety “DP555 BG/RR”

9 planting dates, rainfed vs irrigated38 – 107 years of daily historical weather data

-150

-100

-50

0

50

100

150

Planting date

Rainfed

Yie

ld D

evia

tion

s fr

om N

eutr

al

-150

-100

-50

0

50

100

150

Irrigated

El Niño

La Niña

Climate in the southeastern USAHow do farmers make decisions?

Farmers and Climate Interviews

• 38 farmers

• 21 counties in GA

• Semi-structured interviews - Risk management

strategies

- Access of weather & climate information

Farmers and Climate Risk Reducing Options

Potential Use Freq.Crop selection 23

Planting timing 16

Input management 14

Land management 13

Variety selection 11

Marketing 8

Harvesting dates 4

Insurance 3

Herd management 2

Hog lagoon mgmt. 1

Farmers and Climate Risk Reducing Options

Potential Use Freq.Crop selection 23

Planting timing 16

Input management 14

Land management 13

Variety selection 11

Marketing 8

Harvesting dates 4

Insurance 3

Herd management 2

Hog lagoon mgmt. 1

Forecast Use: Irwin CountySpring 2006 forecast for summer drought widespread shift from

long- to short-cycle peanut variety

Farmer Joe’s Questions

El NiñoLa Niña

Management Decisions• Crop selection• Variety selection• Planting dates• Acreage allocation• Irrigation• Pest management• Amount and type of crop

insurance

WWW.AGROCLIMATE.ORG

Historical weather data (1900-2005)

ENSO Phases

Planting dates

Soil types

Select AL, FL, GAcounties

Yield

Total amount of irrigation

No. of irrigationeventsCSM-CROPGRO

Peanut Model

April 16, 23May 1, 8, 15, 22, 29June 5, 12

Crop Simulations

Georgia

Crop Simulations: Research Analysis

Crop Simulations: AgroClimateExtension, Producers and Consultants

AgroClimate Tools

Interaction &Participation

Forecasts,Climatology

Web-based DSSwww.AgroClimate.org

Climate-based Management

Options

Stand aloneDecision Aid

Tools

Needs for Specific Commodities

Crop Models & Climate-based Tools

Extension Agents& Specialists

Farmers/Growers

Climate in the SoutheasternUSA: How do

farmers make decisions?

Climate Change and Climate Variability

The impact of climate change and climate variability on agricultural production and the potential for mitigation and adaptation

• Future issues can only be studied with simulation models

• “What-If” type of scenarios

Agriculture and Climate ChangeImpact and Adaptation

Camilla, Mitchell County, Georgia

Maximum and Minimum Temperature

Precipitation

Maize Yield (kg/ha) Mitchell County, Georgia, USA

4 varieties, 3 soils, rainfed and irrigatedLong-term historical weather data

Corn Yield (kg/ha) Agriculture and Climate Change

Mitchell County, Georgia, USA4 varieties, 3 soils, rainfed and irrigated

Historical weather GCM-ModifiedCSIROMK2, Scenario IS92a, 2010-2039

Agricultural Irrigation Water Demand forecast for 2011 to 2050

• University of Georgia (UGA) and the State of Georgia Environmental Protection Division

• Purpose: – Prepare forecasts of irrigation water demand

that meet the needs for the agricultural sector of the Georgia economy during the first half of this century.

Model Evaluation

• DSSAT Version 4.5• Five cropping seasons: 2000-2004• Crop Management : UGA Extension

Production Guidelines• Field specific water use data:

Agricultural Water Pumping (AWP) project

Irrigation Depth for CornMitchell County

Irrigation by Month

0

1

2

3

4

5

6

7

8

9

3 4 5 6 7

Month

Inch

es

S1 S2 S3 Obs

Irrigation by Year

0

5

10

15

20

25

2000 2001 2002 2003 2004

Year

Inch

es

S1 S2 S3 Obs

Irrigation Water Amount by Crop

Estimation of Irrigation Amounts

• Use crop models to simulate irrigation depths for multiple years

• Weather data : 1950 to 2007

• For major producing counties – 3 most important soils on which irrigation

occurs – Average planting date for county or region– Estimate daily water application; sum by

month• Corn and Cotton 88• Peanut and Soybean 66

March AprilMay

June July

Maize Monthly Irrigation Amounts

Soybean

CottonMaize

Peanut

Winter OutlookCommunication & Information

Communication & Information

Winter OutlookCell Phone Alerts

Winter OutlookWeather Insurance

• ““We like to tackle and solve some of the world’s most challenging problems,” Friedberg says, on what’s next for The Climate Corporation beyond insuring farmers, “A farmer is about as analog as it gets. To be able tell a farmer this is what’s going to happen at the end of a season, that’s mind-blowing.” TechCrunch, June 14, 2012

The Climate Corporation

Winter OutlookRainfall Insurance

Why do we need a model?

Weather/Climate and Modeling: Crop and Pest Prediction

Current Weather Weather Prediction Climate Prediction

Crop/Livestock/Pest/Disease/Irrigation Model

Bud Break Flowering Harvest Maturity

Information delivery to producers

Social scientists/agronomists/atmospheric scientists & engineers

DSSAT 2014

International Training Program on Crop

Modeling

May 19-24, 2014The University of Georgia,

Griffin, Georgia, USA

Weather conditions and weather-based decision support tools

www.weather.wsu.eduwww.georgiaweather.net

Southeast climate information and tools: www.agroclimate.org

For crop model information: www.DSSAT.net

www.GerritHoogenboom.comGerrit.Hoogenboom@wsu.edu