From Climate Signals.
A massive, growing pool of icy meltwater in the Arctic Ocean is a wild card in future climate scenarios, European researchers said today.
Estimated in 2009 at more than 7,500 cubic km – twice the volume of Africa’s Lake Victoria – and growing, the water could flush quickly into the Atlantic with unpredictable effect when prevailing atmospheric patterns shift, as occurred most recently in the 1960s and 1990s.
The situation is one of many disquieting findings captured by project CLAMER, a collaboration of 17 institutes in 10 European countries to inventory and synthesize the research of almost 300 EU-funded projects over 13 years related to climate change and Europe’s oceans and near-shore waters, and the Baltic and Black Seas.The full inventory and synthesis will be presented at an international conference at the Royal Flemish Academy of Belgium, Brussels, Sept. 14-15.
Oceanographer Laura de Steur of the Royal Netherlands Institute for Sea Research says a mostly clockwise wind pattern for the past 12 years in the Arctic has contained – largely in an area known as the Beaufort Gyre (also called the Canada Basin) – a pool of relatively fresh water from unusually high river discharge and melting sea ice.
When the general atmospheric circulation pattern does shift, the fresh, cold water is expected to enter the North Atlantic, with unpredictable impact on an ocean current system important to both European weather and marine food chain. Signs of such an atmospheric shift appeared in 2009 but the episode was too short to cause a major flush.
Says Dr. de Steur: “The volume of water discharged into the Arctic Ocean, largely from Canadian and Siberian rivers, is higher than usual due to warmer temperatures in the north causing ice to melt. Sea ice is also melting quickly – another new record low for ocean area covered was documented this past January by the National Snow and Ice Data Center (http://nsidc.org/arcticseaicenews) – adding even more freshwater to the relatively calm Arctic Ocean.”