Comparison of aerosol radiative forcing over the Arabian Sea and the Bay of Bengal

Abstract

Aerosols play an important role in controlling the earth’s radiation budget, which influence the climatic processes. Marine aerosols are the single largest contributor of the aerosol optical depth. Ocean Color Monitor data onboard Indian Remote Sensing Satellite Polar Series 4 (IRS-P4) has been analyzed to retrieve the aerosol parameters over the Arabian Sea and the Bay of Bengal. Top of the Atmosphere (TOA) and the surface forcing have been deduced over the Arabian Sea and the Bay of Bengal. The nature of the aerosol forcing and seasonal effects over the Bay of Bengal and the Arabian Sea have been compared. Surface forcing shows strong seasonal influence, which has not been found on the TOA forcing. In general, higher forcing over the atmosphere has been observed over the Bay of Bengal (−30 to −54 W/m 2) compared to those over the Arabian Sea (−26 to −48 W/m 2). During the winter season, the surface forcing over the Arabian Sea (−28 to −45 W/m 2) is observed to be higher than the Bay of Bengal (−25 to −38 W/m 2).