On evaporation from the Indian Ocean

Abstract

 The problem of evaporation from the oceans is briefly reviewed. Seasonal charts of evaporation are presented .for the Indian Ocean area; Combining these charts, with the precipitation charts of Jacobs, the main sources of moisture-supply to the atmosphere in this area are located. From a knowledge of Bowen’s ratio, computations are made of the relative magnitudes of the sensible heat (enthalpy) and the total convective heat-energy lost by the sea- surface to the atmosphere, These computations confirm that the main mode of, energy-transfer in the region of the trades is in the form of latent heat. A comparative discussion is given of the available estimates of the excess of evaporation over precipitation between the latitudes 40oN and 40°8. The question of how far quantitative determinations of the mass-circulation of the trade wind cell and the toroidal and eddy-fluxes of water-vapour across its high-latitude boundaries can provide an independent aerological check on such estimates is examined.