M.G. McPhee, A. Proshutinsky, J. H. Morison, M. Steele, M. B. Alkire, GRS, 36, Rapid change in freshwater content of the Arctic Ocean

Geophysical Research Letters, 36, L10602; doi:10.1029/2009GL037525.

Rapid change in freshwater content of the Arctic Ocean

M. G. McPhee (McPhee Research Co., Naches, WA, U.S.A.), A. Proshutinsky (Woods Hole Oceanographic Institute, Woods Hole, MA, U.S.A.), J. H. Morison (Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, WA, U.S.A.), M. Steele (Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, WA, U.S.A.), and M. B. Alkire (College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, OR, U.S.A.)

Abstract

The dramatic reduction in minimum Arctic sea ice extent in recent years has been accompanied by surprising changes in the thermohaline structure of the Arctic Ocean, with potentially important impact on convection in the North Atlantic and the meridional overturning circulation of the world ocean. Extensive aerial hydrographic surveys carried out in March–April, 2008, indicate major shifts in the amount and distribution of fresh-water content (FWC) when compared with winter climatological values, including substantial freshening on the Pacific side of the Lomonosov Ridge. Measurements in the Canada and Makarov Basins suggest that total FWC there has increased by as much as 8,500 cubic kilometers in the area surveyed, effecting significant changes in the sea-surface dynamic topography, with an increase of about 75% in steric level difference from the Canada to Eurasian Basins, and a major shift in both surface geostrophic currents and freshwater transport in the Beaufort Gyre.

(Received 28 January 2009; accepted 21 April 2009; published 21 May 2009.)

McPhee, M. G., A. Proshutinsky, J. H. Morison, M. Steele, & M. B. Alkire (2009), Rapid change in freshwater content of the Arctic Ocean, Geophysical Research Letters, 36, L10602; doi:10.1029/2009GL037525.

Link to abstract: http://www.agu.org/pubs/crossref/2009/2009GL037525.shtml