Effects of aerosol climatologies on weather forecast in NWP models

We present a study of the effects of different aerosol climatologies on the weather forecast of air temperature at 2 meters over Northern Eurasia using NWP mesoscale COSMO 5.6 model system. The application of different aerosol climatologies (Tanre, Tegen, MACv2) has revealed the differences in air temperature in the regions of southern Europe, Middle East, and Central Asia mainly due to changes in aerosol optical thickness. We show that the application of the modern Macv2 climatology in COSMO-Ru model simulations has led to the improvement of air temperature forecast at 2 meters with the decrease in the root-mean-square error by 0.1–0.2°C (to 0.5°C for some stations). In cloudless conditions, this error reduction can reach 1°C. However, above 850 hPa, the decrease does not exceed 0.1°C.