HR: 09:45h
AN: C51C-08    [Abstracts]
TI: Sea ice properties and processes in a warming Arctic
AU: * Maykut, G A
EM: maykut@serv.net
AF: Dept of Atmospheric Sciences, University of Washington, Seattle, WA 98195 United States
AB: The Arctic sea ice cover is changing. Over the past few decades there has been a marked decrease in the areal extent and thickness of multiyear ice. Open water fraction in summer has been increasing, with corresponding increases in first-year ice fraction during the remainder of the year. Such changes have a profound impact on air-sea-ice interactions in the Arctic. For example, there is increased input of solar heat to the ocean that is producing a positive feedback on ice formation and decay, as well as affecting biological activity in the ice and ocean. Recent observations in the Chukchi and Beaufort Seas help to illustrate the magnitude of the environmental changes. Work during the SHEBA Program has shown substantial thinning of second-year and multiyear ice in this region, with almost half of the total summer melt occurring at the base of the ice due to heat transfer from the ocean. Surface hydrography and tracer studies indicate that solar heating of the mixed layer, enhanced by a more mobile ice cover with larger fractions of leads and open water, plays the major role in ocean-ice heat transfer. Future sea ice research in the Arctic needs to focus strongly on the consequences of these and other ongoing changes. To do so will require interdisciplinary studies that combine field observations and large-scale modeling efforts. Such studies and a more fundamental understanding of the underlying processes are needed to assess potential changes in western Arctic shelf ecosystems and the related impacts on coastal communities.
DE: 3349 Polar meteorology
DE: 4540 Ice mechanics and air/sea/ice exchange processes
DE: 1620 Climate dynamics (3309)
DE: 1635 Oceans (4203)
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting