Ocean fronts around Alaska from satellite SST data

Ocean fronts of the Bering, Chukchi, Beaufort Seas and the Gulf of Alaska are studied from in situ and remote sensing data. The main goal of this study is to produce an up-to-date climatology of all major fronts of the study area and explore the seasonal and interannual variability of the frontal pattern and individual fronts as well as their relations to environmental parameters. All the known fronts of the study area are rigorously determined and their parameters (thermohaline ranges etc.) quantified, from the most complete dataset of cross-frontal hydrographic sections (CTD and bottle data) assembled. The inner, middle, and outer (shelfbreak) fronts of the Bering Sea shelf are traced in the alongshelf direction up to, respectively, the Bering Strait, Gulf of Anadyr, and off of Cape Navarin, and possibly beyond. TS-fronts of the Chukchi and Beaufort Seas are determined and traced in a similar fashion. Relations between TS-parameters of the northern Bering Sea fronts and the Chukchi Sea fronts are explored. Satellite AVHRR data are used to study surface signatures of thermal fronts. The main source of satellite data is the Pathfinder SST data with 9-km resolution, acquired twice-daily over a 12-year period, 1985-1996. This unique dataset is used to objectively derive, map and analyze SST fronts, using the Cayula-Cornillon algorithms for front detection and declouding developed at the University of Rhode Island . The seasonal and interannual variability of the frontal patterns and individual fronts in each sea is explored. Possible relations between the frontal patterns and parameters, on one hand, and various environmental parameters (bottom topography, sea ice cover, air temperature, river runoff, Bering Strait transport, and wind stress), on the other hand, is explored on a variety of scales, from seasonal to interannual to decadal.