NUMERICAL MODELING OF COASTAL UPWELLING IN THE BAY-OF-BENGAL

A baroclinic numerical model is applied to evolve thermal structure ne ar the coast. The driving mechanism consists of wind-stress forcing re presentative of that applied during pre-monsoon (May), monsoon (July), and post-monsoon (November) seasons. During the monsoon season, a lar ge quantity of fresh water is expected to be discharged from the Hoogh li and Mahanadi rivers. Therefore, the simulations are carried out for July with a combination of wind stress and northern boundary forcing. The simulations show that the May winds are favourable for upwelling processes off Visakhapatnam. The upwelling off Visakhapatnam expected in July in the presence of southwesterly surface wind stress forcing i s suppressed by the northern fresh water discharge and replaced by loc al sinking. The simulations for November indicate that the winds are f avourable only for downwelling off Visakhapatnam.