HR: 11:05h
AN: C52A-04 INVITED     [Abstracts]
TI: On large outflows of Arctic sea ice into the Barents Sea
AU: * Kwok, R
EM: ron.kwok@jpl.nasa.gov
AF: Jet Propulsion Laboratory, MS 300-235 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Laxon, S W
EM: swl@cpom.ucl.ac.uk
AF: University College London, Centre for Polar Observation and Modelling Pearson Building, London, WC1E 6BT United Kingdom
AU: Maslowski, W
EM: maslowsk@nps.edu
AF: Naval Postgraduate School, Dept of Oceanography 1 University Circle, Monterey, CA 93948 United States
AB: We find an anomalously high outflow of Arctic sea ice through the passage between Svalbard and Franz Josef Land (S-FJL) during the winter of 2003. This is preconditioned by the unusually high concentration of thick perennial ice over the Nansen Basin at the end of the 2002 summer. Together with a Dec-Mar sea-level pressure pattern, a deep low situated over the eastern Barents Sea, the consequence is an enhancement of ice export through this passage. As well, this winter (Oct through May) saw the lowest Fram Strait ice area flux over the 25 year ice flux record - 288x10$^3$ km$^2$ compared to the mean of 491x10$^3$ km$^2$. The Oct-May ice area flux through the S-FJL passage, at 113x10$^3$ km$^2$, is not only unusual in magnitude but also remarkable in that almost ~70$%$ the area is multiyear ice. Using ice thickness from radar altimetry, we estimate this year's winter ice volume flux to be ~ 350 km$^3$. This can be compared to an export of ~1060 km$^3$ through the Fram Strait over the same period. Examining a 10-year record with satellite motion and thickness estimates, we find the mean volume export through the S-FJL passage to be ~63 km$^3$. Another anomalously large outflow of Arctic sea ice through this passage, comparable to that in 2003, is found in 1996. This southward flux of sea ice represents one of the two major sources of freshwater in the Barents Sea; the other is the eastward flux of water via the Norwegian Coastal Current. With model simulations, the consequences of variability in freshwater input on the Barents Sea hydrography and its impact on transformation of Atlantic Water along its way towards the Arctic Ocean are discussed.
DE: 4207 Arctic and Antarctic oceanography
DE: 4215 Climate and interannual variability (3309)
DE: 1640 Remote sensing
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting