Monday, March 30, 2015

Megadroughts the Future of the U.S., NASA Study Says

The United States will likely experience 'megadroughts' the magnitude of which haven't been experienced in a millennium, due in large part to man-made climate change, a new study conducted by NASA, Columbia University and Cornell University scientists said. 
The study analyzed climate models and tree ring records in portions of at least 16 states and found that global temperature rise due to man-made climate change, and not a lack of precipitation, could increase the chance of the West and Southwest experiencing a megadrought -- a  severe drought lasting decades -- by the year 2100 to more than 80 percent, National Geographic reports.  
"This is an amazing result ... The precipitation is not so dire. It is the escalation in temperature that is driving the model simulations toward dramatic aridity, " David Stahle, a paleoclimatologist at the University of Arkansas points out to LiveScience.com.
A rise in temperatures due to man-made climate change is creating 'unprecedented' drying across the nation, Smithsonian Magazine reports. Such a megadrought could last decades and be worse than the drought which ended the ancient Anasazi civilization more than 1,000 years ago, LiveScience.com says.   
"The future of drought in western North America is likely to be worse than anybody has experienced in the history of the United States," said Benjamin Cook, the study's lead author and a climate scientist at NASA's Goddard Institute for Space Studies in New York City.
Jonathan Overpeck, co-director of the Institute of the Environment at the University of Arizona, says this megadrought may even surpass the severity of megadroughts in medieval times, SmithsonianMag.com reported. 
This drought could prove disastrous for the West as it will impact agriculture, ecosystems and city water supplies significantly, National Geographic reports.
Cook said that some of the potential impacts from such a drought can currently be observed in California, which is in the middle of a record-breaking drought
However, a dire situation for other regions, like the Central Plains,  is still uncertain, LiveScience notes. Tree-ring records used to examine the likelihood of a megadrought in the West are far more detailed than those available on the Plains. 
The future for our Western states looks bleak, but there may be a light at the end of the tunnel.
"I am optimistic that we can cope with the threat of megadrought in the future because it doesn't mean no water. It means significantly less water than we are used to," said Toby Ault, one of the study's researchers from Cornell University.
The study's findings were published on Feb. 12, 2015 in the scientific journal Science Advances.