Modelling of Upwelling Processes during Pre-Monsoon and Monsoon along the West Coast of India

The 3-dimensional Princeton Ocean Model is used in the present study which uses sigma-coordinate system in the vertical. The model has been configured for the west coast of India to study the circulation and coastal upwelling during March-September. The model uses monthly data fields of temperature and salinity from "Levitus94" and monthly wind stress forcing inferred from daSilva94. Both diagnostic and prognostic computations are utilized for understanding coastal circulation and temperature along the vertical transects off some selected locations along the coast. During this period, Lakashadweep Low is also simulated in the South East Arabian Sea. The simulation of coastal upwelling is very predominant during July off the southern coastal stretch and its intensity gradually decreases towards north. The model simulations of temperature and currents are in qualitative agreement with the available in-situ observations and satellite imageries. The effect of freshwater outflow on the circulation from the rivers joining the Arabian Sea is found to be minimal.