Climate Change and Large‐Area Corn Yield in the Southeastern United States

Abstract

AbstractThere is concern about the negative effects that a possible trace‐gas‐induced climate change will have on crop yields. This study determines the effect of climate change already observed on large‐area corn yield (Zea mays L.) in the southeastern USA. Our multiple regression models differ from most previous large‐area models in two important respects. First, we modeled simultaneously the technological trend and the climate. This is required because of the warming of Southeastern nights during the past 50 yr. Second, we used maximum and minimum temperatures, rather than average temperature. Our results generally associate yield reductions with increases in daytime temperatures during the month of corn pollination. In the Middle and Upper South, increased yield is associated with warming of nighttime temperatures during mid‐season. A trace‐gas‐induced warming should produce minimal change in maximum temperatures. Because projections of future climate generally indicate more night warming than day warming, our results argue that Southeastern corn yield will either change very little or may increase slightly beyond the increase normally expected from technological advancement.