Mooring observations of the thermal structure, salinity, and currents in the SE Bering Sea basin

Utilizing recently developed deep-sea mooring technology, we present the first interannual time series measurements of the ocean temperature, salinity, and velocity fields in the Bering Sea basin. These were made during spring and summer of 1992 and 1993 and late winter to summer of 1994, in 2195 m of water. Results show a weak background flow of ∼5 cm/s with semidiurnal tides superimposed. Anticyclonic (clockwise) eddies pass by sporadically, inducing currents up to ∼80 cm/s and depressing the isopycnals and isotherms up to ∼200 m. The thermal structure in the upper 400 m shows a deep temperature maximum from warm Alaskan Stream inflows and a minimum above due to winter cooling. A sea surface cooling event was observed in the late winter of 1994, with cold water penetrating to ∼120-m depth. Spring warming begins in late April to early May of each year, marked by the arrival of the 3.75°C isotherm. The local wind plays little role in forcing ocean currents at the site except at the inertial frequency.

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