Coastal ocean circulation near Barbados, West Indies, spring 1990 and 1991

Abstract

Results are presented of two oceanographic surveys of the coastal waters surrounding Barbados, West Indies, during April and May of 1990 and 1991. In both years, observations of the hydrographic structure were made with a dense grid of conductivity‐temperature‐depth stations over the upper 500 m of the water column. Acoustic Doppler current profiler (ADCP) measurements of currents in the upper 250 m were made on radial transects from the island during three short surveys in each year. One fixed mooring was deployed south of the island for the duration of each cruise. Results from both years showed the circulation to be energetic, highly variable over short timescales, and sometimes flowing contrary to historical means. Surface ADCP and geostrophic flow patterns during 1990 suggested that the Barbados Ridge, north of the island, played an important role in steering the circulation north of the island. The sudden reversal of the current south of the island between legs 1 and 2 of 1990, coupled with the presence of low‐salinity surface water, suggested we may have witnessed an encounter between the island and the northern edge of a thin (less than 35 m) mesoscale pool of Brazilian Current retroflexion region origin. On the other hand, in 1991, several eddies, both cyclonic and anticyclonic, were observed near the island, suggesting the possibility of shedding of Von Karman type eddies from the island.