Caught in a withering drought, California is also shattering a 120-year-old record for heat.
For the first half of 2014, the state has been an average of 4.6 degrees Fahrenheit warmer than normal, and 1 degree warmer than the previous record set in 1934, according to the National Climatic Data Center.
“In the business of climate science, this is a shattering of a record,” said Jonathan Overpeck, of the University of Arizona’s Institute of the Environment. As for what’s driving this unprecedented heat, Overpeck told the Palm Springs Desert Sun, “We are fairly certain that the unusual warmth is mostly due to human-caused global warming.”
California’s current drought, Overpeck added, is a “global warming drought” and a harbinger of things to come.
“I’m just ‘Wow,’ looking at these trends,” Richard Heim, a drought expert with the National Climatic Data Center in Asheville, North Carolina, told USA Today regarding the records being broken in California. “Can it get any worse? Well, the models say yeah. But how much more can we take as a society, as individual people. And how much more of this can the infrastructure and policies that have been put in place to deal with this at the state level, federal level, local level, how much more of this can you guys take?”
Unfortunately for California, it appears the best prospect for easing the brutal drought — a strong El Niño — seems less and less likely. Last week, NOAA’s Climate Prediction Center (CPC) reduced the chance of El Niño to 65 percent. “And if we do see one, it’s likely to be either weak or moderate,” Joe Romm noted.
A new study by German climate scientists reports that weather extremes like the western U.S. drought are becoming much more common as so-called “blocking patterns” in which hot or wet weather lingers over a region are happening twice as often over the past decade. The blocking patterns occur when the normal meandering of the jet stream slows down.
“Since 2000 we have seen a cluster of these events,” Dr. Dim Coumou of the Potsdam Institute for Climate Impact Research told the Guardian. “When these high altitude waves become quasi-stationary, then we see more extreme weather at the surface. It is especially noticeable for heat extremes.”