'Last year's huge drought was a freak of nature that wasn't caused by man-made global warming, a new federal science study finds. Scientists say the lack of moisture usually pushed up from the Gulf of Mexico was the main reason for the drought in the nation's midsection. Thursday's 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. "This is one of those events that comes along once every couple hundreds of years," said lead author Martin Hoerling, a research meteorologist at the National Oceanic and Atmospheric Administration. "Climate change was not a significant part, if any, of the event."
Other scientists have linked recent changes in the jet stream to shrinking Arctic sea ice, but Hoerling and study co-author Richard Seager of Columbia University said those global warming connections are not valid.
Hoerling used computer simulations to see if he could replicate the drought using man-made global warming conditions. He couldn't. So that means it was a random event, he said.