A Meteorology‐Based Aerosol Favorability Index for the Middle East: Long‐Term Trends and Intensification Over 1940–2024

ABSTRACT Atmospheric aerosol occurrence over the Middle East is influenced by meteorological conditions that govern particle mobilization, vertical mixing, and transport. This study develops a Meteorology‐Based Aerosol Favorability Index (MAFI) to characterize the spatiotemporal variability of these conditions across the region from 1940 to 2024. Daily ERA5 reanalysis data for 1940–2024 and MODIS/Aqua aerosol optical depth (AOD) data for 2003–2024 were used to derive and evaluate five meteorological indices: the Thermal Index (TI), Ventilation Index (VI), surface wind‐based Dust Uplift Potential (DUP), Vertical Ascent Index (VA), and Moisture Flux Index (MFI). A Random Forest model was used to estimate the relative importance of the indices in relation to AOD variability and derive their weights for MAFI. TI was the most influential index in spring, summer, and autumn, whereas MFI ranked highest in winter. Seasonal mean MAFI was highest in summer (0.416), followed by autumn (0.375), spring (0.371), and winter (0.286). Mean seasonal Spearman correlations between MAFI and AOD were 0.37 in winter, spring, and summer, and 0.57 in autumn. After false discovery rate (FDR) correction, correlations were statistically significant in 97.8%–99.8% of grid cells. Trend analysis showed significant increases in MAFI across most seasons, with the strongest and most spatially extensive increases in summer. Trends over the satellite era (2003–2024) were weaker than those over the full analysis period (1940–2024). These findings indicate an increase in meteorological conditions favourable to aerosol occurrence and transport across much of the Middle East. However, MAFI represents meteorological favorability rather than aerosol loading itself, and the observed trends cannot be attributed directly to anthropogenic climate change without further detection‐and‐attribution analysis.