Three-dimensional climatology, trends, and meteorological drivers of global and regional tropospheric type-dependent aerosols: insights from 13 years (2007–2019) of CALIOP observations

Abstract. Globally gridded aerosol extinction data from the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) during 2007–2019 are utilized to investigate three-dimensional (3D) climatological distribution of tropospheric type-dependent aerosols and identify trends in column optical depth (AOD), partitioned within different altitude regimes, their meteorological drivers. Using detection samples layer aerosols, we also yield a 3D frequency occurrence (FoO) subtypes classified by CALIOP. The results show that coefficient (AEC) shows contrasting vertical patterns over land ocean, former possessing significant geographical dependence, while enhancement AEC latter is mainly located below 1 km. structures AECs, however, strongly dependent on altitude. When total AOD (TAOD) into planetary boundary (PBL) free troposphere (FT), demonstrate PBL FT contribute 62.08 % 37.92 %, respectively, global TAOD averaged daytime nighttime. Yet this CALIOP-based partitioning varies significantly. Among all 12 typical regions interest analyzed, more than 50 lower (0–2 km), contribution less 2 above 6 In average terms, found FoO layers 4.45 largest “clean marine” (1.79 %) smallest continental” (0.05 %). Overall, exhibit pattern similar AEC. resulting trend analyses CALIOP accurately captures regional anomalies TAOD, as observed other satellite measurements reanalysis. Our correlation analysis between factors suggests interannual variability related precipitation (PPT), volumetric soil moisture (VSM), wind speed (WS) particular regions. For instance, positive equatorial central Pacific attributable increased PPT decreased WS. contrast, dry convective dominated dust smoke, variability/trend largely modified VSM driven PPT. Additionally, further these correlations robust significantly weakened or even reversed FT. This highlights superiority using proxy variable for widely applied explore relationships atmospheric pollution meteorology.