Atmospheric Chemistry and Physics Feedback between dust particles and atmospheric processes over

Abstract. We used the comprehensive model system COSMO-ART to quantify the impact of mineral dust on the radiative fluxes, the temperature and the feedback between dust particles and their emissions. We simulated two dust storms over West Africa in March 2006 and in June 2007. Simulations with and without coupling of the actual dust con-centration with the radiative fluxes and the thermodynamics were carried out for each case. The model results for the 2006 case were compared with observations of the AMMA campaign. At the surface the shortwave radiative effect of min-eral dust can be described by a linear relation between the changes in net surface radiation and the aerosol optical depth (AOD). For an AOD at 450 nm of 1 the average shortwave radiation reduction amounts −140 W m−2 during noon. Th