Daytime Variations Of Absorbing Aerosols Above Clouds And Their Direct Radiative Effects In South Atlantic

Daytime variations of aerosol properties above maritime stratocumulus clouds in the southeast Atlantic are investigated by merging geostationary data from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) with NASA A-Train data sets. SEVIRI's 15-minute above cloud aerosol optical depth (AOD) and below aerosol cloud optical depth (COD) retrieval provides the opportunity to assess their direct radiative effects using retrieved cloud and aerosol properties from solar channels. This approach differs from assumed fixed values from instantaneous polar-orbiting measurements to calculate diurnally-averaged radiative effects. A comparison in the radiative effects between a fixed optical properties and SEVIRI-retrieved optical properties are evaluated. Uncertainty analyses of the estimation of optical properties and radiative effects are addressed.