Scott A. Malcolm

Agricultural Adaptation to a Changing Climate: Economic and Environmental Implications Vary by U.S. Region

Global climate models predict increases over time in average temperature worldwide, with significant impacts on local patterns of temperature and precipitation. The extent to which such changes present a risk to food supplies, farmer livelihoods, and rural communities depends in part on the direction, magnitude, and rate of such changes, but equally importantly on the ability of the agricultural sector to adapt to changing patterns of yield and productivity, production cost, and resource availability. Study findings suggest that, while impacts are highly sensitive to uncertain climate projections, farmers have considerable fl exibility to adapt to changes in local weather, resource conditions, and price signals by adjusting crops, rotations, and production practices. Such adaptation, using existing crop production technologies, can partially mitigate the impacts of climate change on national agricultural markets. Adaptive redistribution of production, however, may have signifi cant implications for both regional land use and environmental quality.

Agricultural Production under Climate Change: The Potential Impacts of Shifting Regional Water Balances in the United States

General circulation models predict significant and accelerating changes in local patterns of precipitation and temperature during the twenty-first century. Agricultures vulnerability to climate change will depend on both the biophysical impacts of climate change on crop yields and on the agricultural systems ability to adapt to changing production conditions. Shifts in the extent and distribution of irrigated and dryland production are a potentially important adaptation response. Farmer flexibility to adapt may be limited, however, by changes in the availability of irrigation water under future climate conditions. This study uses a suite of models to explore the biophysical and economic impacts of climate change on U.S. fieldcrop production under several potential future climate projections, and to explore the potential limits and opportunities for adaptation arising from shifting regional water balances. The study findings suggest that, while irrigation shortages attributable to climate change have varying effects on cropland use, the aggregate impacts on national production are small relative to the direct biophysical impacts of climate change on yield.