On the thermal response of upper eastern Arabian Sea to the summer monsoonal forcing during Monsoon-77

Abstract

The thermal response of upper eastern Arabian Sea to the summer monsoon forcing is documented with the aid of surface marine meteorological and upper ocean temperature (BT) time series data collected from two Indian stationary ships during Monsoon-77. Near surface mixed layer cooled over 2 deg. C and deepened non-penetratively of the order of 25-35 m with the onset and progress of monsoon. Depth-time sections of temperature constructed with daily averaged BT data revealed upwelling below mixed layer resulting a cooling of 2 deg. to 3 deg, C, A double cored maxima in the vertical thermal gradient was noticed only at the northern location while at the southern location a single cored maximum was noticed throughout, Diminishing tendency in the heat content of top most 100 m and 200 m layers was attributed to the upwelled colder waters from below.