A new study finds an increased possibility of severe and long-term megadrought affecting Southwestern United States. John Russell reports.
The Southwestern United States could face a decade long drought according to a new study by Cornell, University of Arizona and U.S. Geological Survey researchers. According to lead author and Cornell assistant professor of earth and atmospheric sciences Toby Ault, climate change is increasing the possibility of a "megadrought" - a drought that could last over thirty years. SOUNDBITE Toby Ault, Cornell assistant professor of earth and atmospheric sciences, saying: "The risk of a decade long drought is normally about 50 per cent but with climate change it goes up to about 80 or 90 per cent according to our results. And for a multiple decade long drought, a megadrought, the risk is usually in the order of 5 to 15 per cent but with climate change it goes up to between 20 and 50 percent for a lot of the Southwest." The study is based on historical data of previous droughts and uses current changes in precipitation patterns caused by global warming to evaluate the risks of severe droughts in the near future. Ault says that while the drought will happen regardless of climate changes, the accelerated rate of these changes could increase the severity of the drought. SOUNDBITE Toby Ault, Cornell assistant professor of earth and atmospheric sciences, saying: "The southwest is not alone in facing this level of risk. Northern Mexico is exposed to similar, if not higher, levels of risk. Australia, parts of South Africa and the Mediterranean all come out on our analysis as being exposed to similar, comparable levels of megadrought risk." While a drought is inevitable, Ault points to the importance of staying optimistic and starting conversations on the use of water. The study will be published in the American Meteorological Society's Journal of Climate.