The Southwest's current drought could be the start of the Dust Bowl-like future that some scientists have already predicted will come from human-caused warming.
Or, it could just be another in the long line of natural, cyclical droughts in this region dating back 1,000 years.
But one of the nation's leading climate scientists, the University of Arizona's Nobel Prize-sharing Jonathan Overpeck, says he's coming to believe there's "a real likelihood" the drought is caused by global warming. New research at the UA backs that up.
Some other scientists disagree, even as leading climate experts generally agree that someday, global warming will make the Southwest drier.
This drought is already known as the region's worst in more than a century and one of the worst in the past 500 years.
The dispute has implications for Tucson's water supply. The drought has already shrunk water levels in the Colorado River, which furnishes Central Arizona Project water that's pumped to Tucson.
If those believing this drought is caused by warming are right, major shortages could occur much sooner than expected on the river, says Connie Woodhouse, a University of Arizona geography professor who has studied tree-ring records to understand river runoff patterns.
Full Story: http://www.azstarnet.com/allheadlines/235060.php