Improved Understanding of Ocean Circulation

GRACE tracks near-surface and deep-ocean currents to improve our understanding of ocean circulation. Earlier this year, a NASA study detected a previously unknown redistribution of freshwater during the past decade from the Eurasian half of the Arctic Ocean to the Canadian half. Yet despite the redistirbution, they found no change in the net amount of freshwater in the Arctic that might signal a change in the global "ocean conveyor belt" that redistributes heat around our planet, allaying concerns that melting Arctic sea ice could be increasing the amount of freshwater in the Arctic enough to impact global ocean circulation. In the image here, increasing freshwater on the U.S. and Canadian side of the Arctic from 2005 to 2008 is balanced by decreasing freshwater on the Russian side, so that on average the Arctic did not have more freshwater. Blue represents maximum freshwater increases and yellows and oranges represent maximum freshwater decreases.

Image credit: University of Washington