Comparisons between the distributions of dust and combustion aerosols in MERRA-2, FLEXPART, and CALIPSO and implications for deposition freezing over wintertime Siberia

Abstract. Aerosol distributions have a potentially large influence on climate-relevant cloud properties but can be difficult to observe over the Arctic given pervasive cloudiness, long polar nights, data paucity remote regions, and periodic diamond dust events that satellites misclassify as aerosol. We compared 2008–2015 mineral combustion aerosol from Cloud-Aerosol Lidar Infrared Pathfinder Satellite Observation (CALIPSO) satellite, Modern-Era Retrospective analysis for Research Applications, Version 2 (MERRA-2) reanalysis products, FLEXible PARTicle (FLEXPART) dispersion model. Based coincident, seasonal Atmospheric Sounder (AIRS) satellite meteorological data, may occur up 60 % of time in winter, it hardly ever occurs summer. In its absence, MERRA-2 FLEXPART each predict vertical horizontal distribution large-scale patterns aerosols with relatively high confidence (Kendall tau rank correlation > 0.6), although sizable amount variability is still unaccounted for. They do same dust, except conditions conducive formation where CALIPSO likely misclassifying near surface (< ∼ km) overpredicting local emissions. Comparisons ground suggest concentrations improved by addition sources. All three products predicted wintertime most frequently Siberian regions common winter. This suggests impacts ice phase processes particularly Siberia, further model validation non-CALIPSO observations needed. assessment paves way applying model-based simulations range regional-scale aerosol–cloud interaction studies greater confidence.