As a result of global warming the chances of the southwestern United States a 30-year-long "megadrought" may be as high as 50 percent.
A research team also predicted the chance of a decade-long drought in the region was at least 50 percent, Cornell University reported.
"For the southwestern U.S., I'm not optimistic about avoiding real megadroughts," said Toby Ault, Cornell assistant professor of earth and atmospheric sciences and lead author of the paper. "As we add greenhouse gases into the atmosphere - and we haven't put the brakes on stopping this - we are weighting the dice for megadrought conditions."
California is currently in a state of D4 "exceptional drought," which is the most sever category possible; Oregon, Arizona, New Mexico, Oklahoma and Texas all fall somewhere in between moderate and exceptional drought.
"With ongoing climate change, this is a glimpse of things to come. It's a preview of our future," Ault said.
In a computer model the researchers demonstrated the possibility of what would be the worst drought in over 2,000 years. It also showed parts of Washington and Montana were at a lower risk of drought. Southern Africa, Australia, and the Amazon basin are also vulnerable to the possibility of experiencing megadroughts.
"These results help us take the long view of future drought risk in the Southwest - and the picture is not pretty. We hope this opens up new discussions about how to best use and conserve the precious water that we have," said Julia Cole, UA professor of geosciences and of atmospheric sciences," Ault said.
The National Science Foundation, National Center for Atmospheric Research, the U.S. Geological Survey and the National Oceanic and Atmospheric Administration funded the research. The study, , "Assessing the Risk of Persistent Drought Using Climate Model Simulations and Paleoclimate Data," were published recently in the Journal of Climate.
