Climate Change and Agriculture in the Great Lakes Region

Potential Impacts of Climatic Variability and Change

Jeffrey A. Andresen

Dept. of Geography

Michigan State University

Climate Change andAgricultural Productivity

• Crop, forage productivity and production costs– Changing temperature, precipitation

– CO2 enrichment

– Occurrence of extremes

Climate Change andAgricultural Productivity

• Soil suitability– Soil Erosion– Oxidation of organic matter

Climate Change andAgricultural Productivity

• Livestock productivity and production cost

– Animal mortality– Feed conversion rates– Rates of gain– Milk production– Conception rates

Climate Change andAgricultural Productivity

• Irrigation water supply– Changes in precipitation frequency and totals– Changes in groundwater recharge rates– Changes in nonagricultural usage

Annual trends (yr-1) for selected simulated variables, soybean, 1895-1996

StationPPT(mm)

PET(mm)

ET/ PETPAVfp

(mm)

S(mm)

Yield (kg/ha)

WUE (kg/ha/mm)

Chatham .722 .126 .190* .235* -.032 9.188* .024*

Coldwater .066 -.326* .079* .167 -.236* 1.783 .007

Eau Claire .227 -.133* .084* .000 -.233* 4.543* .009*

Grand Rapids

1.881* .090 .224* .250* -.308* 9.652* .020*

Madison .465 .047 .080* .185* -.079 4.944* .010*

Waseca 1.286* -.373* .193* .479* -.294 15.069* .032*

Worthing-ton

-.235 -.564* .126* .167 -.164 6.390* .014*

* Trend significant at =0.05 level

Projected Changes in Climate: Great Lakes Region

• While considerable differences and uncertainty exist, the majority of future climate simulations suggest a warmer and wetter climate across the region.

Estimated changes in national crop production in 2030 relative to 2000

(Reilly et al., 2001)

Crop Dryland Yield

Irrigated Yield

Irrigation Water Use

Corn +11 to +20%

+1 to +21% -32 to +57%

Soybeans +7 to +49% +23% 0 to +18%

Soft Wheat -3 to +58% -5 to +5% -26 to +3%

Potatoes +7 to +8% -4 to –1% -3 to 0%

Ratios of GCM-projected future and POR historical scenario crop yields averaged over all stations

Alfalfa Maize Soybean

Scenario HADCM2 CGCM1 HADCM2 CGCM1 HADCM2 CGCM1

Future without CO2 vs. Historical

1.06 1.06 1.11 1.26 1.13 1.24

Future with CO2 vs. Historical

1.18 1.16 1.23 1.40 1.64 1.81

Future with CO2 vs. Future without CO2

1.11 1.09 1.11 1.11 1.45 1.46

Simulated Historical and Projected Future Growing Season and Water Balance for Maize, Bay City, MI

Precipitation (mm)

Evapotrans-piration (mm)

Runoff(mm) Drainage(mm)Change in storage(mm)

Time Period

HAD CGCM HAD CGCM HAD CGCM HAD CGCM HAD CGCM

2026 – 2035 410 314 -460 -432 -50 -20 -7 -5 106 143

2090 – 2099 394 267 -394 -364 -53 -29 -5 -4 57 130

Histor-

ical 321 -410 -48 -7 145

Agricultural strategies for coping with climate change

• Adaptation– Learn to change, adapt

• Mitigation– Reduction of carbon and other GHG

• Carbon sequestration• Production of fuels/energy from biomass/animal waste• Reduction of CH4 and N2O• Use of alternative energy sources in production

Probability Distribution of Simulated Dryland Double Crop Soybean Yields

by Planting DateAdrian, MI, 1895-2000

0

500

1000

1500

2000

2500

00.20.40.60.81

Probability

Yield (kg/ha)

1-Jun

15-Jun

1-Jul

15-Jul

Probability Distribution of Simulated Irrigated Double Crop Soybean Yields

by Planting Date Adrian, MI, 1895-2000

0

500

1000

1500

2000

2500

3000

3500

4000

4500

00.20.40.60.81

Probability

Yield (kg/ha)

1-Jun

15-Jun

1-Jul

15-Jul

Summary

• A changing climate leads to many potential challenges for agricultural production systems.

• Observed climate has become wetter and cloudier in the Great Lakes Region, especially during the last 50 years.

• The single most important climatological variable associated with crop yields regionally is precipitation. Growing season length and GDD accumulation were relatively more important at northern study sites.

Summary (continued)

• The warmer and wetter climate suggested by the many GCM projections for our region would suggest yield increases for many crops. Yields of some crops in the region might decline.

• A significant portion of any future yield increases will be associated with CO2 enrichment.

• Recent research results suggest greater agronomic potential for northern sections of the region, even with less suitable soils.

• More research is needed, especially regarding indirect impacts of climate change and extreme events.