A semi-diagnostic calculation of climatic circulation in the western Indian Ocean

A 3-dimensional, semi-diagnostic circulation model is used to compute the climatic circulation in the upper levels of western tropical Indian Ocean (20 degrees S-30 degrees N and 35 degrees E-80 degrees E) during the premonsoon month of May. The model involves the sea surface topography function used as the integral function, and is driven with the wind stress at the surface and thermohaline forcing at different levels. A steady state solution is obtained within 40 days of model integration. Computed currents are compared with available observations on currents at selected regions in the model area and it has been found that both agreed fairly well. Computed results are also explained in terms of the model forcing parameters and the dynamics considered in the model.