Composites of Florida State University winds (1970-1999) for four different climate scenarios are used to force an Indian Ocean model. In addition to the mean climatology, the cases includes La Nina, El Nino and the Indian Ocean Dipole (IOD). The differences in upper ocean water mass exchanges between the Arabian Sea and the Bay of Bengal are investigated and shows that during El Nino and IOD years, the average clockwise Indian Ocean circulation is intensified, while its is weakened during La Nina years. As a consequence, high salinity water export from the Arabian Sea into the Bay of Bengal is enhanced during El Nino and IOD years, while transport of low-salinity waters from the Bay of Bengal into the Arabian Sea is enhanced during La Nina years. This provides a venue for interannual salinity variations in the northern Indian Ocean.