FY 1986

Sea ice dynamics and regional meteorology for the Arctic Polynya Experiment (APEX)—Bering Sea 1985

Pease, C.H., R.M. Reynolds, G.A. Galasso, V.L. Long, S.A. Salo, and B.D. Webster

NOAA Tech. Memo ERL PMEL-64, NTIS: PB86-148038/XAB, 120 pp (1985)

This memorandum summarizes the deployment of drifting ARGOS buoys, some with GOES ice stations in the northern Bering Sea, and stationary GOES meteorological stations on St. Lawrence Island in support of the Arctic Polynya Experiment (APEX). Weather conditions during January 1985 over the eastern Bering Sea and western Alaska were extremely anomalous with the warmest air temperatures on record and the least ice ever recorded for the month, both due to prolonged southerly winds throughout the month. During the last three weeks in February, the wind shifted to northerly, air temperatures dropped to -20 to -30°C, and the ice recovered its previous maximum both by freezing in situ and by the return of Bering Sea ice from the Chukchi Sea. Flying conditions were generally very good during this period, so all the buoys and drifting stations were deployed between 19 and 23 February. The ARGOS buoys initially drifted south to southwestward. The buoys deployed on the west side of St. Lawrence Island turned and drifted northward on 27 February and the buoys deployed on the east side of the island turned on 28 February. This is consistent with the idea that reversals (periods of southward flow) in Anadyr Strait are of shorter duration than in Shpanberg Strait, although this was certainly one of the longest reversals ever observed for Anadyr Strait. After 7 March, the buoys on the west side of St. Lawrence again drifted southwestward and the buoys on the east side of the island drifted southward. There was considerable strain over the arrays. Particularly, the eastern array lost two ARGOS buoys on the southward transit past St. Lawrence Island, one on the northward transit and one along the western end of Nunivak Island due to crushing or shear. Both arrays exhibited greater deformation than the MIZEX-West array did while passing St. Matthew Island during 1983.