Global warming has increased risk of record heat, say Stanford scientists

http://www.eurekalert.org/pub_releases/2013-09/su-gwh090413.php

Public release date: 5-Sep-2013
Contact: Noah Diffenbaugh
Stanford University

Drought shriveled crops in the Midwest, massive wildfires raged in the West and East Coast cities sweltered. The summer of 2012 was a season of epic proportions, especially July, the hottest month in the history of U.S. weather record keeping.

And it's likely that we'll continue to see such calamitous weather.

In the north-central and northeastern United States, extreme weather is more than four times as likely to occur than it was in the pre-industrial era, according to a new study by Noah Diffenbaugh, a Stanford associate professor of environmental Earth system science, and Martin Scherer, a research assistant in the department.

Diffenbaugh and Scherer found strong evidence that the high levels of greenhouse gases now in the atmosphere have increased the likelihood of severe heat such as occurred in the United States in 2012.

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