Study says global warming threatens to create a Dust Bowl-like period. Water politics could also get heated.

The driest periods of the last century — the Dust Bowl of the 1930s and the droughts of the 1950s — may become the norm in the Southwest United States within decades because of global warming, according to a study released Thursday.

The research suggests that the transformation may already be underway. Much of the region has been in a severe drought since 2000, which the study’s analysis of computer climate models shows as the beginning of a long dry period.

The study, published online in the journal Science, predicted a permanent drought by 2050 throughout the Southwest — one of the fastest-growing regions in the nation.

The data tell “a story which is pretty darn scary and very strong,” said Jonathan Overpeck, a climate researcher at the University of Arizona who was not involved in the study.

Richard Seager, a research scientist at Lamont-Doherty Earth Observatory at Columbia University and the lead author of the study, said the changes would force an adjustment to the social and economic order from Colorado to California.

“There are going to be some tough decisions on how to allocate water,” he said. “Is it going to be the cities, or is it going to be agriculture?”

http://www.latimes.com/news/science/la-sci-swdrought6apr06,0,122112.story?coll=la-home-headlines