Sandra Hines and Alan Buis in University of Washington Today: A hemisphere-wide phenomenon – and not just regional forces – has caused record-breaking amounts of freshwater to accumulate in the Arctic’s Beaufort Sea.Frigid freshwater flowing into the Arctic Ocean from three of Russia’s mighty rivers was diverted hundreds of miles to a completely different part of the ocean in response to a decades-long shift in atmospheric pressure associated with the phenomenon called the Arctic Oscillation, according to findings published in the Jan. 5 issue of Nature.
The new findings show that a low pressure pattern created by the Arctic Oscillation from 2005 to 2008 drew Russian river water away from the Eurasian Basin, between Russia and Greenland, and into the Beaufort Sea, a part of the Canada Basin bordered by the United States and Canada. It was like adding 10 feet (3 meters) of freshwater over the central part of the Beaufort Sea.
“Knowing the pathways of freshwater in the upper ocean is important to understanding global climate because of freshwater’s role in protecting sea ice – it can help create a barrier between the ice and warmer ocean water below – and its role in global ocean circulation. Too much freshwater exiting the Arctic would inhibit the interplay of cold water from the poles and warm water from the tropics,” said Jamie Morison, an oceanographer with the University of Washington’s Applied Physics Laboratory and lead author of the Nature paper.
...“Changes in the volume and extent of Arctic sea ice in recent years have focused attention on the impacts of melting ice,” said co-author Ron Kwok, senior research scientist with the Jet Propulsion Laboratory in Pasadena, Calif. “The combined GRACE and ICESat data allow us to now examine the impacts of widespread changes in ocean circulation.”...
River near Monchegorsk in Russia, crossing M18-road. Shot by kallerna, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license
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