Interaction of the summer monsoon current with water surface Over the Arabian Sea

Abstract

A critical examination has been made of the papers Colon (1964) and Bunker (19651 on the subject. Bunker’s data are for days when there were weal monsoon conditions as Judged from subsequent rainfall on the west coast of the Peninsula; Colon's data are for active or strong monsoon conditions on the west coast. Convergence in lower levels in the eastern Arabian Sea within about 500 km of the coast due to falling jet velocities or decrease in speeds cannot alone explain the large amounts of rainfall over the area and the coast. Presence of (1) characteristic airmass stratification over the Arabian sea and (2) the Western Ghats, is largely responsible for considerable precipitation over and off the coast and in making the moist current about 6.0 km deep over the Peninsula. The inversion is due to airmasses and not due to subsidence.

            A model for vertical distribution of airmasses over the Arabian Sea when there is characteristic airmass stratification during active or strong monsoon conditions on the West coast is suggested and data for variations of low level jet given by Bunker are discussed with reference to the same.