HR: 0830h
AN: OS21C-1142    [PDF]
TI: Interannual Variability of Sea-ice over the Eurasian Shelf Seas and its Interaction with Large-scale Atmospheric Circulation
AU: * Zhang, X
EM: xdz@iarc.uaf.edu
AF: International Arctic Research Center, University of Alaska Fairbanks, 930 Koyukuk Dr., Fairbanks, AK 99775 United States
AU: Walsh, J E
EM: jwalsh@iarc.uaf.edu
AF: International Arctic Research Center, University of Alaska Fairbanks, 930 Koyukuk Dr., Fairbanks, AK 99775 United States
AU: Bhatt, U S
EM: bhatt@iarc.uaf.edu
AF: International Arctic Research Center, University of Alaska Fairbanks, 930 Koyukuk Dr., Fairbanks, AK 99775 United States
AB: It has been documented that the sea-ice over the Eurasian shelf seas has large variance on interannual time scale. Not only does the sea-ice in this area serve as a freshwater source in solid form but also its variability considerably affect oceanic freshwater distribution. In this study, we detected dominant spatiotemporal modes of the interannual variability of sea-ice over the Eurasian shelf seas (from the Barents Sea to the East Siberian Sea) by a frequency domain singular value decomposition of monthly sea-ice concentration data from HadISST1.1 from 1979-2002. Three significant oscillatory modes, with periods of quasi-biennial, 4.5 year and 5-6 year, are isolated. These modes explain about 60-70% of the total variance at their respective local frequency. The reconstructed time evolution of spatial patterns show that the 5-6 year mode has stationary characteristics with large fluctuations over the Barents and Kara Seas, the 4.5 year mode has two centers of action in the Barents-Kara Sea and the western Laptev Sea, respectively, with the larger fluctuations in the Barents-Kara Sea, and the quasi-biennial mode has two centers of action located over the Barents-Kara Sea and the western Laptev-East Siberian Sea, respectively. Apparent feature of eastward propagation of sea-ice anomaly appears in the quasi-biennial mode. This analysis extends to sea level pressure and surface air temperature to examine coherence of sea-ice and atmospheric variability and to investigate their interactions.
DE: 1635 Oceans (4203)
DE: 1655 Water cycles (1836)
DE: 4215 Climate and interannual variability (3309)
DE: 4283 Water masses
DE: 4532 General circulation
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting