Estimating Global Impacts to Agriculture from Climate Change Accounting for Adaptation

Abstract

Climate change threatens global food systems, but the extent to which adaptation will reduce losses remains unknown. Here, we empirically estimate the net impact of producer adaptations around the world using longitudinal data on six staple crops spanning 12,658 sub-national units, capturing two-thirds of global crop calories. We project that adaptation and income growth nearly halve global losses at end-of-century, but substantial residual losses remain for all staples except rice. Global damages are dominated by losses to modern-day breadbaskets that currently exhibit limited adaptation due to favorable climates. We estimate global production declines 5.8 x 10^14 kCal annually per 1C rise in global mean surface temperature (4.6% of current production or 130kCal/person/day, per 1C; p<0.001). These results suggest a scale of innovation, cropland expansion and/or additional adaptation that might be necessary to ensure global food security in a changing climate.