Mechanisms of summertime upper Arctic Ocean warming and the effect on sea ice melt
Article first published online: 6 NOV 2010
Copyright 2010 by the American Geophysical Union.
Journal of Geophysical Research: Oceans (1978–2012)
Volume 115, Issue C11, November 2010
How to Cite
2010), Mechanisms of summertime upper Arctic Ocean warming and the effect on sea ice melt, J. Geophys. Res., 115, C11004, doi:10.1029/2009JC005849., , and (
- Issue published online: 6 NOV 2010
- Article first published online: 6 NOV 2010
- Manuscript Accepted: 10 AUG 2010
- Manuscript Revised: 15 JUL 2010
- Manuscript Received: 1 OCT 2009
- Arctic Ocean;
- ocean warming;
- sea ice melt
 In this study, we use a numerical sea-ice-ocean model to examine what causes summertime upper ocean warming and sea ice melt during the 21st century in the Arctic Ocean. Our first question is, “What causes the ocean to warm in the Pacific Sector during the summer”? We find that about 80% of total heating over this region comes from ocean surface heat flux, with the remaining 20% originating in ocean lateral heat flux convergence. The latter occurs mostly within a few hundred kilometers of the northwest Alaskan coast. In the summer of 2007, the ocean gained just over twice the amount of heat it did over the average of the previous 7 years. Our second question is, “What causes sea ice to melt in the Pacific Sector during summer”? Our analysis shows that top melt dominates total melt early in the summer, while bottom melt (and in particular, bottom melt due to ocean heat transport) dominates later in the summer as atmospheric heating declines. Bottom melt rates in summer 2007 were 34% higher relative to the previous 7 year average. The modeled partition of top versus bottom melt closely matches observed melt rates obtained by a drifting buoy. Bottom melting contributes about 2/3 of total volume melt but is geographically confined to the Marginal Ice Zone, while top melting contributes a lesser 1/3 of volume melt but occurs over a much broader area of the ice pack.