Climate change is likely intensifying California’s record-breaking drought, according to a Columbia University study released Thursday.
Researchers say the drought is a mostly natural phenomena, but blamed man-made global warming for increasing its intensity, by up to 20 percent.
“Recent drought was naturally driven and modestly intensified by warming,” the report says in a summary of its findings. “Warming has rapidly amplified the probability of severe drought.”
The paper says the root cause of the drought is a “persistent ridge of high atmosphere pressure” that has blocked wet weather from reaching California and its parched Central Valley.
Researchers say that global warming has likely contributed to the drought by sapping soil of its moisture, to the tune of 8 percent to 27 percent between 2012 and 2014.
The researchers, led by Columbia University climate scientist A. Park Williams, projected that global warming is likely to exacerbate future droughts in much the same way. They warned that droughts are likely to increasingly impact society by reducing groundwater reserves.
Global warming, the report said, “has intensified the recent drought as part of a chronic trend toward enhanced drought that is becoming increasingly detectable and is projected to continue growing throughout the rest of this century.”
President Obama and Gov. Jerry Brown (D-Calif.) have both blamed climate change for contributing to California’s drought, which is now in its fourth year.
The drought has kicked up political battles as well. The White House has said it’s willing to work with Congress on reforming the way wildfire efforts are funded, but Republican efforts to increase the water supply for California’s Central Valley have stalled due to Democratic opposition.