A new study has revealed that the U.S. Southwest and Central Plains could experience drought in the last half of this century and that these events could be far worse than what these regions have experienced over the last 1,000 years.
Researchers of the study published in the journal Science Advances on Thursday have warned that these droughts could be far longer and drier and that elevated emissions of greenhouse gas could increase the risks of severe droughts in these areas.
Study researcher and climate scientist Ben Cook, from NASA's Goddard Institute for Space Studies, said that natural droughts such as the Dust Bowl that occurred in the 1930s and the drought that is currently happening in the Southwest historically lasted a decade or less but their results suggest of droughts that can last for at least 30 years.
It also appears that the amount of carbon released into the atmosphere can influence the severity of such droughts. Cook said that odds of a megadrought, which lasts more than three decades, is currently at 12 percent but the likelihood of it happening in the Southwest and Central Plains in the years 2050 to 2099 could go up to 80 percent if current emissions continue to rise.
To come up with their prediction, Cook and colleagues looked at the record of climate derived from tree rings from the past 1,000 years. Tree rings hint of how much moisture the tree receives for a given year based on their width.
The researchers then used 17 climate models that incorporate data of soil moisture to come up with a drought prediction for the Southwest and Central Plains over the next century if emission of greenhouse gas remains unabated and if the emissions are moderated.
"In both the Southwest and Central Plains, we're talking about levels of risk of 80% of a 35-year-long drought by the end of the century, if climate change goes unmitigated," said study co-author Toby Ault, from Cornell University.
Ault nonetheless said that actions can still be made to curb the effects of the increasing amount of greenhouses gases on the world's temperatures.
Droughts would mean water shortages and crop failures. Cook said that although there are current strategies for dealing with these events such as the usage of groundwater and the development of drought resistance crops, if future drought become more severe, these strategies may need to be extended or new ones may be needed.
