‘Life-Threatening’ Rain Targeting New Orleans Has Climate Link

(Bloomberg) -- The kind of ‘life-threatening’ rainfall that could flood New Orleans from Hurricane Ida likely has a link to climate change. 

Warmer air means hurricanes can hold more water-vapor, which leads to an increase in intense downpours. The atmosphere can hold about 7% more moisture for every 1 degree Celsius (1.8 Fahrenheit) the world’s temperature rises, according to scientists. And Earth’s temperatures have risen 1.1 degrees Celsius in the last century, according to the latest report by the UN Intergovernmental Panel on Climate Change.

“Any given hurricane today is holding more water and producing more precipitation than an equivalent strength hurricane would have produced 30 or 40 years ago,” said Daniel Swain, a climate researcher at the University of California at Los Angeles and the Nature Conservancy. 

New Orleans could see as much as 12 inches of rain from Ida, according to the National Weather Service. That could cause widespread flooding throughout the city even if its levee system holds back an expected storm surge. Even before Ida arrives, New Orleans will be drenched with torrential downpours bringing as much as 2 inches of rain Friday, with some areas getting as much as 6 inches, according to a flash flood watch issued by the National Weather Service.

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