New study: California's epic drought probably wasn't caused by climate change http://t.co/K8Ep0PdNPr pic.twitter.com/ymA4qYq4bM
— Mother Jones (@MotherJones) December 9, 2014But according to new research by the National Oceanic and Atmospheric Administration, California's drought was primarily produced by a lack of precipitation driven by natural atmospheric cycles that are unrelated to man-made climate change. In other words, climate change may have worsened the impacts of the drought, but it isn't the underlying cause.
"The preponderance of evidence is that the events of the last three winters [when California gets the majority of its precipitation] were the product of natural variability," said lead author Richard Seager, a Columbia University oceanographer.
"The preponderance of evidence is that the events of the last three winters were the product of natural variability."
Over the last three years, Seager said, unpredictable atmospheric circulation patterns, combined with La Niña, formed high-pressure systems in winter over the West Coast, blocking storms from the Pacific that would have brought rain to California. The result has been the second-lowest three-year winter precipitation total since record-keeping began in 1895. But that pattern doesn't match what models predict as an outcome of climate change, said Seager. In fact, the study's models indicate that as global warming proceeds, winter precipitation in California is actually predicted to increase, thanks to an increased likelihood of low-pressure systems that allow winter storms to pass from the ocean to the mainland. Tim McDonnell/Mother Jones
