2016-03-28. Scientists Find a Way to Predict U.S. Heat Waves Weeks in Advance.

posted Mar 29, 2016, 3:03 AM by Alan Gould
By Henry Fountain, The New York Times. For GSS Climate Change chapter 8. Excerpt: Deadly summer heat waves in the eastern United States may be predictable nearly two months before they occur, giving emergency planners and farmers more time to prepare, scientists reported on Monday. The key to such an advance forecast, scientists said, is the occurrence of a distinctive pattern of water temperatures across a wide stretch of the North Pacific Ocean. While the existence of the pattern does not guarantee that a heat wave will occur, it significantly increases the odds of one happening as much as 50 days later. ...From 1999 to 2010, about 620 people died each year, on average, from heat-related illness in the United States, according to the Centers for Disease Control and Prevention. ...In a study published on Monday in the journal Nature Geoscience, the researchers first identified extremely hot summer days in the eastern half of the country from 1982 to 2015. Then they looked at temperature data for sea surfaces — specifically, the extent to which temperatures were above or below normal — for the same period. “The pattern popped out at us really clearly,” said Karen A. McKinnon, a postdoctoral researcher at the National Center for Atmospheric Research, in Boulder, Colo., and the lead author of the study. Not only did it exist on those hot days — defined as about 12 degrees hotter than normal summer temperatures — “but importantly, up to seven weeks before,” Dr. McKinnon said....  http://www.nytimes.com/2016/03/29/science/heat-wave-predictions-weather.html