Permanent drought could strike the Southwest U.S. by 2050, thanks to global warming, and experts predict water wars, as cities and farmers face shortages. Computer models show that the drying has already begun. Jonathan Overpeck, a climate researcher at the University of Arizona, says the data tell “a story which is pretty darn scary and very strong.”
Researchers warn that the country's fastest-growing region should prepare to address issues of water allocation between cities and agriculture, and between states. “This is a situation that is going to cause water wars,” said Kevin Trenberth, a scientist at the National Center for Atmospheric Research. (More environment stories.)