USA's heavy rain events rising due to climate change

by Dave Gram, USA Today, July 31, 2012

MONTPELIER, Vt. – Nearly a year after the remnants of Hurricane Irene unleashed devastating floods in much of Vermont, a new report by an environmental group says extreme downpours and snowfalls are the new normal — up 85% in New England since 1948.

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  By Austen Danforth, AP
  Bennington Police Chief Paul Doucette looks at a collapsed bridge on Aug. 28, 2011, in Bennington, Vt. The remnants of Hurricane Irene dumped torrential rains on Vermont.

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By Austen Danforth, AP

Bennington Police Chief Paul Doucette looks at a collapsed bridge on Aug. 28, 2011, in Bennington, Vt. The remnants of Hurricane Irene dumped torrential rains on Vermont.

Nationally, Environment America's report found that storms with extreme precipitation increased in frequency by 30% across the contiguous United States from 1948 to 2011. 

It said the largest annual storms produced 10% more precipitation, on average. 

It said New England was the region where the trend was most pronounced. Intense storms more than doubled in New Hampshire during the period studied while increasing 84 percent in Vermont. 

The report, which analyzed 80 million daily precipitation records from the contiguous U.S., attributed the increase in severity of the downpours in part to global warming. 

The report did not come as a surprise either to the head of the Vermont Public Interest Research Group (VPRIG) which released it in the state Tuesday, or to Andy Nash, meteorologist in charge at the National Weather Service station in South Burlington. Paul Burns, executive director of VPIRG, said Irene was Vermont's third major flood of 2011. He agreed that the extreme weather should be taken as evidence of climate change caused by humans. 

"This report proves that the storms really are getting worse, and if we want to reduce the likelihood of more devastating storms in the future, it's time now to stand up to all those who continue to deny science, shirk responsibility and oppose progress on clean energy solutions," Burns said. 

[snip -- local denier rubbish]

Higher temperatures cause greater evaporation and help the air hold more water. The group said it used data from 3,700 weather stations and a methodology originally developed by scientists at the National Climatic Data Center and the Illinois State Water Survey. Environment America defined an extreme storm as the average biggest annual rainfall or snowfall during a 24-hour period at a given location.

http://www.usatoday.com/weather/climate/globalwarming/story/2012-07-31/heavy-rain-climate-change-global-warming-environment-america/56621946/1