Agriculture is the industry whose fate is most closely linked to climate, and California is by far the biggest agricultural producer in the country.So some economists say that California's agriculture is optimized for its weather, along with its soil, labor, market, etc. Just like agriculture everywhere else.
The state grows more than half of the nation's fruits, nuts and vegetables and is virtually the sole source of more than a dozen crops, including nectarines, raisins, artichokes and olives. Texas is a distant second, bringing in less than half of the $26 billion grossed by California farmers and ranchers.
Other states may escape relatively unscathed, and some studies show that the uptick in temperature and longer growing season predicted by climate models could actually be a boon to agriculture in the northernmost states.
But California's climate is already close to ideal for many of the fruits and vegetables it is famous for, and even the most optimistic predictions show California on the losing end. ``At the current crop mix that we have, we're pretty much at the optimum, so changing that would push us over the peak of that curve,'' said economist Olivier Deschjnes of the University of California-Santa Barbara.
In a forthcoming study in the American Economic Review, Deschjnes and Michael Greenstone of the Massachusetts Institute of Technology estimated that global warming will result in a 4 percent, or $1.3 billion, increase in agricultural profits for the United States by the end of the century. But California may see an annual loss of 15 percent, or $750 million.
Any climate change will cause disruptions, but it is reasonable to assume that farmers will adapt, and optimize their crop production for the new weather conditions. If you want to measure the effect of global warming, then you should compare current production to the likely optimized production of the future.
For certain weather-sensitive crops like premium wine grapes, any change at all is likely to change what grape farms produce the best grapes. This change is as likely to be for the better or for the worse. There is no chance that we will run out of premium wine grapes. These newspapers that run scare stories about how premium wine production might fall by 4% are irresponsible.