Randolph E. Schmid, Associated Press
April 5, 2007 — Changing climate will mean increasing drought in the Southwest — a region where water already is in tight supply — according to a new study.
"The bottom line message for the average person and also for the states and federal government is that they'd better start planning for a Southwest region in which the water resources are increasingly stretched," said Richard Seager of Columbia University's Lamont Doherty Earth Observatory.
Seager is lead author of the study published online Thursday by the journal Science.
Researchers studied 19 computer models of the climate, using data dating back to 1860 and projecting into the future. The same models were used in preparing the reports of the Intergovernmental Panel on Climate Change.
The consensus of the models was that climate in the southwestern United States and parts of northern Mexico began a transition to drier conditions late in the 20th century and is continuing the trend in this century, as climate change alters the movement of storms and moisture in the atmosphere.
The reduction in rainfall could reach levels of the 1930s Midwest dust bowl, Seager said in a telephone interview.
That doesn't mean there would be dust storms like those of the 1930s, Seager said, because conditions at that time were also complicated by poor agricultural practices. But he said the reduction in rainfall could be equivalent to those times when thousands of farmers abandoned their parched land and moved away in search of jobs.
