Using the AIR Weather Index to Estimate the Contribution of Climate to Corn and Soybean Yields in the U.S.

Using historical production data at the county level and statistical analysis, we investigate climate contributions to corn and soybean yields between 1974-2003. Crop yield trends are decomposed into two components: the technology-derived trend and the trend resulting from climate variability. Implications for agricultural risk management and farm policy are discussed.