ABSTRACT

This chapter provides preliminary estimates of the potential effects of climate change on global agriculture. It focuses on identifying the sensitivities of the system, the types of market responses one might expect from the agricultural system, and issues requiring further research. Climatologists use general circulation models (GCM)—large, complex computer models—to test the sensitivity of the climate system to increases in greenhouse-gas concentrations in the atmosphere. The broad changes in climate projected by GCMs offer some guidance for assessing agricultural effects, but, to evaluate regional-specific effects on crop growth, they must be complemented with more-detailed information on specific daily and seasonal patterns of temperature and precipitation. Changes in agricultural production in other countries, especially from producers, affect global agricultural prices and trade flows that in turn affect consumer and producer welfare in the United States (US). The global and US welfare effects as a percentage of world gross domestic product from the scenarios are quite modest.