"Running air conditioners is not a formula for sustainable living," said Becker. "It's not good news for the planet that people are choosing a lifestyle that is dependent on more energy."
If these scientists and their models are correct, severe drought could ignite conflicts over water that will have epic effects on development, immigration and even international politics.
"Being in the desert is unnatural," said Seager. "The whole Southwest is dependent on massive works of engineering, all of which were built assuming there would be more water available than there really is. How is that whole system going to stand up to this kind of stress? Who gets the water?"
Droughts as far back as the medieval period have devastated populations across the United States. During the medieval period, a series of megadroughts of multi-decadal length struck the West and one of these, at the end of the 13th century, has been linked to the demise of the Anasazi culture.
The Dust Bowl on the Plains in the 1930s and droughts in 1950s had catastrophic effects on agriculture, migration and employment. Since the recent drought of the 1990s and 2000s, the water levels in Nevada's Lake Mead and Arizona's Lake Powell are only half full.
Without smart growth and good planning, says Seager, a long-lasting modern drought could stretch water resources to the "point of social conflict."
Border and immigration conflicts could flare as drought in Mexico pushes thousands more poor, rural migrants into the United States looking for work. International treaties with that country may also be strained in the quest for water.
Lamont Doherty scientists said adjustments can be made to deal with the change, perhaps by withdrawing some land from production and by conserving water in urban areas. But green policies often collide with green backs.
"We like to think that a developed country can adjust to these things," said Seager. "But look at the catastrophic response to Katrina.That doesn't inspire confidence at all."