Comparison of Circulation Estimates and Winds Based on Shipboard and Satellite-Tracked Buoy Data in Bransfield Strait, 9-14 March, 1985, Part 3

摘要

The INPE freely drifting prototype oceanographic buoy (System ARGOS) was launched successfully on 9 March at 19:31 GMT, for a several day test experiment. During the 9 to 14 March, 1985, interval, a set of 7 hydrographic stations was made in the Bransfield Strait to obtain information about temperature, salinity and density. Results of the several day drifter trajectory are presented together with a comparison with geostrophic circulation, surface winds and air and sea temperatures. Mean drifter velocity was 27.0 cm/s toward 042 deg and confirmed a predicted NE movement for the surface water layer. The surface geostrophic current was toward 020 deg at 4 cm/s, at 10 m depth the current was toward 045 deg at 5 cm/s. Best agreement was found between the rifter trajectory and the geostrophic current at 10 m depth. At the time of buoy launch and for about one day thereafter, winds were weak and toward 090 deg; after another day, however, the surface winds changed and blew generally toward 250 deg at speeds that gradually increased up to 16 kts, in opposition to the surface water motion. Air and water temperatures measured from the buoy are also discussed and compared with measurements made at the hydrographic stations.