A new federal report says last year's drought was a freak of nature and can't be blamed on man-made global warming.

Spencer Platt, Getty Images

Scientists say the main cause of the drought in the nation's midsection was the lack of moisture that usually pushes up from the Gulf of Mexico.

The report by dozens of scientists from five different federal agencies looked into why forecasters didn't see the drought coming. The researchers concluded that it was so unusual and unpredictable that it couldn't have been forecast.

They focused on six states but the drought spread much farther.

Study lead author Martin Hoerling of the National Oceanic and Atmospheric Administration said the jet stream that brings moisture north was stuck unusually north in Canada.


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