California Can Blame Climate Change for a Fifth of its Drought

Speaking to the paper’s significance, Jonathan Overpeck, co-director of the Institute of the Environment at the University of Arizona, said: “It’s important to have quantitative estimates of how much human-caused warming is already making droughts more severe”.

But the Columbia researchers say rising temperatures, which have crept up “in step with building fossil-fuel emissions”, are making things worse by driving moisture from plants and soil into the air. The study estimates that global warming may have worsened the natural drought by contributing as much as 25 percent, The Washington Post reports.

“A lot of people think that the amount of rain that falls out the sky is the only thing that matters”, said Mr. Williams. “But warming changes the baseline amount of water that’s available to us, because it sends water back into the sky”.

He explained further to Al Jazeera America: “Rising temperatures mean we have to get more rain just to break even. Each raindrop and each snowflake is a little less valuable”. That increase, combined with the lack of rainfall in California over the last few years, quickened the moisture loss in already dry soil and trees. He estimated that global warming probably accounted for about 15% to 20% of the drought severity. “When this happens, the danger is that it will lull people into thinking that everything is now OK, back to normal”, said Williams.

“It used to be that half the years were warm, and half were cool”, Dr. Noah Diffenbaugh, the Stanford study’s lead author, told The New York Times. Wildfires are accelerating, reservoirs are drained, cropland is out of production and farm worker unemployment is growing.

Researchers at the University of California – Davis (UCD) also tried to quantify how the drought is affecting the state’s economy through the agriculture industry. “But it’s definitely made worse by global warming”. “It would be a fairly bad drought no matter what”.

Earlier this month, Governor Brown penned an open letter to Republican presidential candidates ahead of their first debate, asking them to detail their plans to address climate change. JamesInhofe, R-Okla., calls the link between human activities and climate the “biggest hoax perpetrated against mankind”. The state’s snowpack, which is crucial for the state’s water supply, diminished to virtually nothing. The Triple-R, as it’s been dubbed, has been lingering over the Pacific Ocean and steering storms away from California’s coast.

“The real driver of the drought of course has been the drop in precipitation”, Seager said in an interview.

Other research bolsters the case for a connection between warming and the intensity of the drought. A March study out of Stanford University said that California droughts have been intensified by higher temperatures, and gives similar warnings for the future. By the 2060s, Williams said, more or less permanent drought conditions will set in, with evaporation overpowering short bursts of intense rainfall.