LAUSR

Abstract Understanding the global distribution pattern of aerosol particles is of paramount importance as it has applications of many fields that include, but are not limited to energy and environment, the study of aerosol particles is building blocks for nanotechnology. Therefore, the keen observation of aerosols through satellite remote sensors namely: MODIS (Moderate Resolution Imaging Spectroradiometer) and CALIOP (Cloud–Aerosol Lidar with Orthogonal Polarization) is important. The newly launched MODIS collection 6.1 (C061) aerosol product are containing three different aerosol inversion algorithms such as the Dark Target (DT) algorithm for land, the DT algorithm for the ocean, and the Deep Blue (DB) algorithm for land. In this study, we have used a combined aerosol product based on DT and DB to present emerging patterns in global and regional aerosol characteristics over short-term (2001-2007) and long-term (2001-2018) observation periods. The CALIOP, a Lidar instrument on aboard of the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite which presents the 3-dimensional view of aerosol climatology, is also used during special cases to investigate the aerosol distribution patterns. Based on MODIS observations the aerosol distribution patterns show strong seasonal differences. The seasonal characteristics vary with latitude and longitude across the globe. The regional characteristics clearly showed their region-specific behavior. Interestingly, MODIS observations captured high concentrations over the regions traced in the developing countries particularly South and East Asia, where observations show strong seasonality. The averaged MODIS AOD trend over global is found slightly negative. On regional scales, positive trends found over the Arabian Peninsula, Africa (Sahel), Eastern China, Northern part of India. These regions are next to major monsoon regions. The increasing concentration of aerosols over these regions may modulate the monsoon rainfall distribution pattern. In contrast, the negative trend observed over Eastern America, Europe, the southeast part of Africa as well as in the associated dust outflow over the North Atlantic.