FY 1988

Geostrophic flow in the Central Bering Sea, Fall 1986 and Summer 1987

Reed, R.K., J.D. Schumacher, and A.T. Roach

NOAA Tech. Report ERL 433-PMEL 38, NTIS: PB88-174354, 13 pp (1988)

Data from a synoptic CTD survey over a large region in the central Bering Sea in fall 1986 are used to derive the major features of circulation. Geopotential topographies reveal the following flows: (1) a well-developed eastward flow that subsequently turned toward the northwest; (2) a cyclonic gyre north of Amukta Pass; and (3) a weak flow, with some local intensifications, paralleling the continental slope. Volume transports, relative to 1000 db, in these branches (in the order above) were approximately (1) 4 × 10 s s (2) 2 × 10 m s; and (3) 1 × 10 generally, but -4 × 10 m s in two locations. Also, a northward inflow through Amukta Pass was inferred from subsurface temperature. Data from a cruise in summer 1987 reveal a relatively strong northward flow through Amchitka Pass but the absence of inflow in Amukta Pass. Previous climatological and synoptic data sets have shown numerous eddylike features that appear to be transient. Comparison of results from various circulation patterns suggests that the eastward flow that turns toward the northwest frequently occurs.