Effects of climate change on US crop production: simulation results using two different GCM scenarios. Part I: Wheat, potato, maize, and citrus

摘要

We projected US agricultural production in 2030 and 2090 at 45 representative sites, using 2 scenarios of climate change, developed with the Hadley Centre Model and the Canadian Centre Climate Model, and the DSSAT (Decision Support Systems for Agro-technology Transfer) dynamic crop-growth models. These simulation results have previously been aggregated nationally with the aid of economic models to show an increase in overall US agricultural output under climate change. In this work, we analyzed the regional distribution of the simulated yields, showing that positive results largely depend on the precipitation increases projected by the climate scenarios. In contrast, in some important rainfed production areas where precipitation was projected to decrease, such as the Kansas and Oklahoma Bread Basket regions under the Canadian Centre Climate Model scenario, climate change resulted in significant reductions of grain yield (-30 to -40%), accompanied by increased year-to-year variability. We also discussed the response to additional factors affecting the simulated US crop production under climate change, such as higher temperature and elevated CO2. [References: 19]