Thermohaline structure in the equatorial Indian Ocean during Monsoon-77

Abstract

The hydrographic and BT data sets collected in the upper 200 m water column along three zonal transects (2°N, equator and 2°S) in the equatorial Indian Ocean (between 70oE and 90OE) made by USSR ships during the field observational programme of Monsoon-77 (end May/early June 1977) showed prominent eastward depression of thermocline in association with the surface easterly equatorial jet. In the central indian. Ocean, the mixed layer cooling and deepening rates were weak with the. Onset and sway of the summer monsoon over a two month period from end May 1977, but relatively significant changes were noticed in the salinity of the upper 200 m water column. In this region, on a synoptic scale a mild increase in SST is in accor4ance with the net surface heat gain during the last week of July 1977.