“The changes in cropping that we quantified with remotely sensed data were stunning,” Mustard said. “We can use those satellite data to better understand what’s happening from a climate, economic, and sociological standpoint.”

The study showed that temperature increases of 1 degree Celsius were associated with substantial decreases in both total crop area and double cropping. In fact, those decreases accounted for 70 percent of the overall loss in production found in the study. Only the remaining 30 percent was attributable to crop yield.

“Had we looked at yield alone, as most studies do, we would have missed the production losses associated with these other variables,” VanWey said.

Taken together, the results suggest that traditional studies “may be underestimating the magnitude of the link between climate and agricultural production,” Cohn said.

That’s especially true in places like Brazil, where agricultural subsidies are scarce compared with places like the U.S.

“This is an agricultural frontier in the tropics in a middle-income country,” VanWey said. “This is where the vast majority of agricultural development is going to happen in the next 30 to 50 years. So understanding how people respond in this kind of environment is going to be really important.”

VanWey said a next step for this line of research might be to repeat it in the U.S. to see if increased subsidies or insurance help to guard against these kinds of shocks. If so, it might inform policy decisions in emerging agricultural regions like Mato Grosso.

Source: Impact of climate change on agriculture may be underestimated — ScienceDaily