Global warming could overheat crops

SEATTLE, Jan. 9 (UPI) -- U.S. researchers say global warming is likely to result in lower crop yields in the tropics and subtropics. leading to serious food shortages.

The food shortages could hurt half of the world's population, said David Battisti, a University of Washington atmospheric sciences professor.

The report, published in the journal Science, said higher temperatures in the tropics can be expected to cut yields of the primary food crops, maize and rice, by 20 percent to 40 percent. Rising temperatures also are likely to play havoc with soil moisture, cutting yields even further.

"The stresses on global food production from temperature alone are going to be huge, and that doesn't take into account water supplies stressed by the higher temperatures," Battisti said Thursday in a release.

Co-author Rosamond Naylor, director of Stanford University's Program on Food Security and the Environment, warned that it will take decades to develop new food crop varieties that can better withstand a warmer climate.

"We have to be rethinking agriculture systems as a whole, not only thinking about new varieties but also recognizing that many people will just move out of agriculture, and even move from the lands where they live now," Naylor said.