Storms in a Warming Climate

http://floodlist.com/america/usa/us-record-rainfall-unprecedented-predicted

15 August, 2014 by Richard Davies

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The intensity of extreme precipitation seen in the USA this week is exactly how the National Climate Assessment had predicted.

The National Climate Assessment (NCA) report of May this year said:

Heavy downpours are increasing nationally, especially over the last three to five decades. Largest increases are in the Midwest and Northeast. Increases in the frequency and intensity of extreme precipitation events are projected for all U.S. regions.

The report goes on to demonstrate that rainfall totals in the heaviest rain events in the Northeast have increased by 71% since 1958.

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The NCA report is in no doubt that the increase in rainfall intensity is down to a changing climate.

Warmer air can contain more water vapor than cooler air. Global analyses show that the amount of water vapor in the atmosphere has in fact increased over both land and oceans. Climate change also alters dynamical characteristics of the atmosphere that in turn affect weather patterns and storms. In the mid-latitudes, where most of the continental U.S. is located, there is an upward trend in extreme precipitation in the vicinity of fronts associated with mid-latitude storms. Locally, natural variations can also be important.

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tags: extreme weather