Adapting to climate change: Facing the consequences | The Economist

A fine-grained analysis of historical data from the United States by Wolfram Schlenker of Columbia University and Michael Roberts of North Carolina State University found such thresholds for maize (corn), soya and cotton, America’s largest crops by value. One extremely hot day, their model suggests, can cut annual productivity by 7%. Applying their findings to models of a world with unabated emissions, they found yield declines of 63-82% by the end of the century, with hefty drops even in the relatively clement first half.

This study, like many, made no provision for CO2 fertilisation.