Analysis of the Winter AOD Trends over Iran from 2000 to 2020 and Associated Meteorological Effects

High aerosol levels pose severe air pollution and climate change challenges in Iran. Although regional optical depth (AOD) trends have been analyzed during the dusty season over Iran, specific factors that are driving spatio-temporal variations winter AOD influence of meteorological dynamics on remain unclear. This study analyzes long-term Iran period 2000–2020 using updated Modern-Era Retrospective Analysis for Research Applications version 2 (MERRA-2) Moderate Resolution Imaging Spectroradiometer (MODIS) datasets. Our results showed exhibited a significant upward trend 2000–2010 followed by decrease 2010–2018. We found important this arid region due to multiple mechanisms which also affect following spring/summer period. Ground-based observations from Aerosol Robotic Network data (AERONET) Middle East display comparable those both MERRA-2 MODIS indicated aeolian dust associated with it play central role changes. Furthermore, downward sea level pressure (SLP) early (2000–2010) induced hot dry winds originated desert regions Iraq Arabia blew toward reducing relative humidity (RH) raising temperature thus promoting soil drying accumulation. In contrast, increase SLP late (2010–2018) cold wet northwestern increased RH lowered temperature, AOD. suggests changes highly influenced seasonal variabilities. These highlight importance examining wintertime climatic their effects East.