Latitudinal variations of aerosols in the MABL over Bay of Bengal

Advection of aerosols from adjoint continental regions into the Bay of Bengal (BoB) is considered important in view of its potential aerosol radiative impacts on Indian summer monsoon. WICARB was conducted to study the spatio-temporal heterogeneity in AODs and aerosol mass concentration during the winter time. Measurements of AOD over BoB in W-ICARB campaign coupled with the MODIS level 3 data over the region are investigated to bring out the mean picture of AOD and the deviations in daily AODs from monthly means. The AODs are found to show a steep latitudinal gradient as the ship moves away from the coast towards the pristine oceanic region. Increased AOD at 500 nm and aerosol mass loading noticed with increase in latitude. The total mass concentration is found to vary between 15 and 45 μg m^-3, with higher loadings near the east coast and northern parts of BoB. Latitudinal gradients in AOD and water vapor indicated higher aerosol loading with low water vapor situations over north BoB region suggesting predominance of coarse mode aerosols on certain occasions.