Relation Between Air-Sea Exchange over the Arabian Sea and the Fluctuations of the Western Indian Summer Monsoon.

To determine the thermal structure and modifications of the summer monsoon air mass of the Arabian Sea, the author draws on observations made by research aircraft during the summer of 1963. Five-day running averages of daily marine meteorological data over the sea were computed for the period June 20 through July 19, 1963. These averages, centered at the middle date of each five-day period, were substituted in transfer equations to compute quasi-synoptic scale daily transfer of latent heat and sensible heat between the sea and the atmosphere. Patterns of latent heat transfer and its transport along the surface four-day trajectories were considered relative to fluctuations in precipitation at the west coast of India. Conclusions are that air-sea exchanges over the sea do not control the fluctuations but are themselves influenced by variation in intensity of the mid-tropospheric subtropical cyclone, which depends for its onset on the moisture supply from the Bay of Bengal and is the main rain-producing system at the west coast of India. 63 pp. Ref.