A Hotter Planet Doesn’t Have to Be Hungrier: Michael J. Roberts - Businessweek

In its most recent report, in 2007, the Intergovernmental Panel on Climate Change concluded, “Globally, the potential for food production is projected to increase with increases in local average temperature over a range of 1 to 3 degrees Centigrade.”
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Research just published by my colleagues David Lobell, of Stanford University, and Wolfram Schlenker, of Columbia University, estimates that climate change has already caused a 4 percent to 5 percent reduction in world production of wheat and corn. This happened even though North America has thus far escaped warming during crucial growing-season months. If warming proceeds as the IPCC has projected, an extrapolation based on historical relationships between yield and weather indicates that, by 2035, U.S. yields will be 20 percent to 30 percent lower than they would have been without warming. By 2085, that shortfall will be as much as 80 percent.
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If world prosperity were not so disparate, I suspect we could easily adapt to climate change. We might eat less meat, build space-age greenhouses or industrialize food production on a scale beyond anything heretofore dreamed. Or we might all start growing our own gardens and keeping chickens. We would spend a greater share of our income on food, but life would be a far cry from Malthusian misery.