Will The Sunbelt Dry Up?

"More than anything else, lack of water could define the limits to America's future growth. If global warming, manmade or otherwise, is contributing to a drying out of both the Southeast and the Southwest, then that's trouble, because those regions are where people are headed: older people, in search of cheap land and dry heat, and younger people chasing jobs in high-tech industries that are shifting south, attracted by lower taxes and laissez-faire state governments.

Arizona is the fastest-growing state in the union. Its population increased by 3.6 per cent last year. Nevada is No. 2: Its population grew by 3.5 per cent. Both are mostly desert.

Tuscon and Phoenix - with populations of a million and four million, respectively - are sprawling toward each other, and are expected to merge in the next decade. Planners project a Phoenix-Tucson population of 10 million within 30 years. Even without worsening drought, that will exceed the capacity of existing water supplies - and Phoenix has supplemented its groundwater supplies by diverting rivers, such as the Colorado. Further increasing Phoenix's water capacity could mean impoverishing water supplies elsewhere.

The long-term prospects for Southern California are deeply troubling. A recent study by the Lamont-Doherty Earth Observatory at Columbia University warns that global warming, though it will actually increase precipitation overall, will entrench current dry conditions in the American southwest permanently within a couple of decades...Global warming or no, there will be future droughts, and no one expects anything other than continued growth in the southeast and southwest."