Historical Adaptability of U.S. Maize to Climate Change: A Reassessment

Abstract

The threat that climate change poses on food security is accentuated by the fact that we need to increase our food supply in light of a growing global population and higher per capita demand. The prospect of these challenges is made all the more alarming by several studies in the scientific and economic literature that have found no evidence of successful adaptation to climate change by farmers. This paper uses the “Long Differences” approach employed in previous works to reassess the evidence in U.S. maize farming for adaptation to temperature changes. It demonstrates that the results of these adaptation analyses are sensitive to the choice of the number of weather stations used to calculate the weather data for the model, with much stronger successful adaptation observed when using only one weather station as compared to seven, as in past studies. This difference in results is due to the suppression of extreme temperatures that arises from the latter’s averaging process, and so the single weather station data are proposed here to be a better representation of the weather that crops actually experience. The systemic deflation of any indication for adaptation obtained in previous studies is analyzed both empirically and analytically through a simplified version of the model. The conclusions drawn here of successful past adaptation offer a more optimistic outlook in terms of the prospect for mitigating some of the future effects of climate change on food production through farmer adaptation.