Outflow of continental aerosols from peninsular India to Bay of Bengal

Abstract

Aerosols are complex entities to assess in the atmosphere. This complexity arises due to their high variability both spatially and temporally, because of the different types of sources at different locations and their transport to different locations. Aerosols produced over a particular region are often transported to other regions due to atmospheric circulation. Aerosols, usually produced close to the Earth’s surface, can get transported to higher altitudes in the atmosphere by various mechanisms such as convective eddies, eddy diffusion, and dispersion. This high variability and transportation of aerosols is portrayed here by choosing two different locations, Bangalore and the Bay of Bengal (BoB). Measurements carried out at these locations, along with satellite data and models, are utilized to investigate the spatial heterogeneity and the transport of aerosols from peninsular India to the Bay of Bengal. Ship-borne measurements of aerosols over the BoB have revealed the influence of continental anthropogenic activity over the ocean. It was also observed that the sea-salt production rate is influenced by the salinity conditions prevailing over the BoB, which contradicts previous observations over other oceans, but aligns with controlled lab experiments. The vertical distribution of aerosols, studied using a micro-pulse lidar, indicates the presence of elevated aerosol layers, which is indicative of transport.