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The present study documents the winter aerosol optical depth (AOD) trends over the Eastern Mediterranean and Middle East (EMME) region using MERRA‐2 and moderate‐resolution imaging spectroradiometer (MODIS) collection 6.1 data. A significant upward AOD trend was identified during the years 2000–2010, whereas the AOD followed a significant downward trend during the years 2010–2017. Our analysis indicates that aeolian dust is the main contributor to AOD changes. The winter AOD changes are related to meteorological factors over the EMME region. During the early period (2000–2010), a significant decrease in sea level pressure induced dry and hot southeasterly winds blowing from the desert regions in the Middle East toward the EMME, which increased the temperature and reduced the relative humidity, thus enhancing evaporation and promoting soil drying. In contrast, during the late period (2010–2017), a significant increase in sea level pressure, accompanied by an increase in the North Atlantic Oscillation (NAO) index, induced northwesterly winds from higher latitudes, which decreased the temperature and increased the relative humidity, reducing dust mobilization in the EMME, in particular, in Iraq and Egypt. This shows to what extent AOD trends in the EMME region are controlled by changing meteorological weather conditions.

This study assessed the aerosol climatology over Iran, based on the monthly data of aerosol optical depth (AOD) derived from the reanalysis-based Modern Era Retrospective Analysis for Research and Applications (MERRA-2) and the satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS). In addition, sea level pressure, wind speed, temperature, relative humidity, precipitation, and soil moisture from the ERA5 reanalysis dataset were applied to investigate the climate-related effects on temporal AOD changes. Our analysis identified positive and negative AOD trends during 2000–2010 and 2010–2018, respectively, which are likely linked to aeolian dust changes. The dust-driven AOD trends were supported by changes in the Ångström exponent (AE) and fine mode fraction (FMF) of aerosols over Iran. During the early period (2000–2010), results of AOD-meteorology correlation analyses suggest reduced soil moisture, leading to increased dust emissions, whereas our results suggest that during the later period (2010–2018) an increase of soil moisture led to decreased AOD levels. Soil moisture appears to be a key factor in dust mobilization in the region, notably in southwestern Iran, being influenced by adjacent mineral dust sources. These phenomena were affected by large-scale sea level pressure transformations and the associated meteorology in the preceding winter seasons. Using a multiple linear regression model, AOD variability was linked to various meteorological factors in different regions. Our results suggest that climatic variations strongly affect the dust cycle, with a strong dependence on wintertime conditions in the region.