Issues in the Impacts of Climate Variability and Change on Agriculture

Abstract

As the title of this special issue suggests, the commonality of the papers included herein is a focus on the interaction of agriculture with climate variability and change in the southeastern United States. The range of topics covered is considerable , from climate modeling to remote sensing to economics. All papers result from two major projects funded by NASA MTPE and the U.S. EPA NCQERA. In addition, the USDA-ERS funded part of one study concerning economics of agriculture under climate change. We chose to study the Southeast because it possesses characteristics that we assumed would further our main project interests, which included exploration of the uncertainty of spatial scale of climate scenarios, uncertainties in modeling adaptation in agricultural assessment work, and exploration of relationships between large scale climate modes, vegetation condition, and local daily weather variables. A central question thus arises: do the papers represent true regional studies, being fundamentally about the southeastern U.S., or do the papers concern methodological/conceptual studies, wherein the Southeast should be viewed as an apt application region? Most of the papers are hybrids, embodying characteristics of both types of studies (regional and methodological), but on balance the Southeast serves more as an apposite application region. The Southeast is an agriculturally diverse region, where a wide variety of crops are grown. It produces about 40% of the national total value of cotton, 23% of rice, and a considerable portion of the total value for most vegetables and citrus fruits. While not significant in terms of total national production, wheat, corn, soybean, and sorghum are also produced (Hansen et al., 2001). It is a region that could be highly vulnerable to climate change given its current climate, which is probably above the optimum (in terms of temperature), for such crops as wheat and soybeans. It is also a region with physiographic characteristics that suggest it might benefit from application of higher resolution scenarios for a climate change assessment of agriculture. Such characteristics include the presence of mountains (Appalachians), complex land-use patterns, and complex coastlines. Furthermore, it is a region that has been considerably studied from the point of view of the influence of large scale climate modes, such as El Niño-Southern Oscillation, on its climate, vegetation, and crop production. This collection of characteristics and previous research indicated thus that the Southeast would act as an excellent application region for our research goals. The first five papers form an integrated project concerning the uncertainty in agricultural and economic impacts that result from varying scales of climate change Climatic Change 60: 1-6, 2003.