Long-term trends in Aerosol Optical Depth obtained across the globe using multi-satellite measurements

Although trends in the Aerosol Optical Depth (AOD) have been examined broadly but effects due to prevailing background conditions on these still remain uncertain, for which a multivariate regression trend model has implemented this study. Long-term AOD across globe are obtained from multi-satellite measurements that include MODerate resolution Imaging Spectral-radiometer (MODIS on-board Terra (T) and Aqua (A), between 2001 2020), Multi-angle Spectral-Radiometer (MISR, 2001–2020), Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP, 2006–2020) observations using both linear as well analysis. Before evaluating trends, detailed comparison made ground-based AEronet RObotic NETwork (AERONET) (2001–2020) more than 80 stations covering globe. A high (above 0.7) medium (from 0.3 spatial correlation is noticed among all satellite except CALIOP (over few sites) observations. However, MISR (CALIOP) observed values underestimated (overestimated) measured by AERONET over aerosol loaded regions. In addition, Modern-Era Retrospective analysis Research Application version-2 (MERRA-2) dataset also able simulate mean decreasing mostly seen connection implementation of emission control policies (Eastern North America, Europe, Eastern Central China), reduction forest fires (South America), stilling surface winds arid regions (Western Africa). On other hand, perceived South Africa region increased reported earlier. Surprisingly, sensor shown rather significantly Middle-East region. When compared, region-wise declined give any statistically significant huge variability such Africa, Middle-East, China, Indian These robust findings will form firm basis evaluate dependence physical chemical characteristics so impact varied aerosols sources can be quantified accurately different • measurements. policies. Region-wise values. further evaluation characteristics.