Plains, Southwest headed for decades-long droughts, say climate scientists
© Copyright Agri-Pulse Communications, Inc.
WASHINGTON, Feb. 12, 2015 - Imagine the 1930s Dust Bowl going on for decades. Researchers say that's what the Plains and Southwest could be in for later in this century because of climate change.
A new study released Thursday says droughts in the latter half of this century are likely to be more severe than even the decades-long “megadroughts” that hit the Southwest and central Plains during Medieval times - “an unprecedented fundamental climate shift.”
"Even when selecting for the worst megadrought-dominated period, the 21st century projections make the megadroughts seem like quaint walks through the Garden of Eden." Jason Smerdon, a co-author and climate scientist at the Lamont-Doherty Earth Observatory, part of the Earth Institute at Columbia University.
Another scientist on the project, Toby Ault of Cornell University, said in a webinar with reporters that the future megadroughts could be as severe as the 1930s or 1950s droughts and last for at least 35 years.
The scientists used 17 different climate models to analyze the future impact of rising temperatures on the regions. They compared those models to two global warming scenarios, one that assumed that the rise in greenhouse gases would continue unabated and another that assumed the emissions would moderate over the century.
Each scenario would result in major droughts.
[Learn about the benefits of subscribing to Agri-Pulse. Sign up for your four-week free trial Agri-Pulse subscription.]
Previous forecasts have projected that the region would be plagued by more severe droughts as the climate changes, but the researchers said their study was the first to show that the droughts could be worse than those the region experienced during the Medieval period. Scientists have estimated the severity of drought during that period by studying tree rings.
“Our results point to a markedly drier future that falls far outside the contemporary experience of natural and human systems in Western North America, conditions that may present a substantial challenge to adaptation,” the scientists reported in the study published online Thursday in Science Advances, an sister, open-access publication of the journal Science.
The scientists cited the ongoing Sahel drought in Africa as a current example of a megadrought.