Climate change threatens West's water, world's crops

The potential that global warming has to dry up water resources in the American West and the food supplies of 1 billion people in the poorest regions of Africa and Asia are the focus of two studies released today.

One of the studies published in the journal Science found that nearly 60% of the changes in river flow, snow pack and winter temperatures in the West over the past 50 years are due to warming caused by human activities, such as the burning of fossil fuels like coal, oil and natural gas.

"We're headed for a potential disaster because of the lack of snowpack," says lead author Tim Barnett, a marine research physicist at Scripps Institution of Oceanography at the University of California, San Diego. "In California, we don't have enough reservoirs, so we rely heavily on the Sierra snowpack for our water."

Already, the changes of the past five decades have meant less snow pack and more rain in the mountains, rivers that run dry by summer, and overall drier summers in the region.



http://www.usatoday.com/weather/climate/globalwarming/2008-02-01-water-crops_N.htm