Spatiotemporal variations of Modelled Aerosols and Aerosol Subtypes over a Tropical region in South India: The Influence of Meteorology Dynamics

Aerosols plays a crucial role in climate dynamics and human health through atmospheric processes. Their effects, both direct and indirect, contribute to the cooling and warming of the earth. This paper provides an analysis of the spatiotemporal variation of different types of aerosols over Andhra Pradesh (AP) state in South India, retrieved from the Modern-Era Retrospective Analysis for Research and Application, Version 2 (MERRA-2) reanalysis data. We comprehensively analysed the datasets on the aerosol optical depth (AOD) and the optical depths of their subtypes (Black Carbon, Organic Carbon, Dust, Sea Salt, and Sulphate). The significant results revealed that the higher AOD observed in the northern coastal AP were influenced by anthropogenic emissions and natural sources such as sea spray and wind-blown dust. Seasonal trends indicate an elevated AOD during the premonsoon period due to an increase in the transportation of dust and during monsoon because of the high humidity and sea salt aerosols; meanwhile, in the winter and postmonsoon seasons, we discovered lower AOD levels. In addition, the anomalies in the AOD were primarily linked to meteorological parameters such as wind patterns, temperature, and relative humidity, as well as emissions from the different industrial, vehicular, and agricultural activities in the central and northern parts of AP. This study highlights the influence of synoptic meteorological conditions, including monsoonal wind dynamics and regional temperature variations, which leads to the spatial distribution and transport of aerosols types. These findings provide crucial insights into aerosol dynamics over AP state, aiding in air quality management and climate impact assessments.