Temporal Variations of Absorbing Aerosols above Clouds

Geostationary data from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) and radiative transfer calculations are used to track and assess optical properties of absorbing aerosols above clouds (AAC) and their radiative effects over the southeast Atlantic. With SEVIRI's high temporal resolution (15-minute), we assess the diurnal variation of AAC during austral winters (May – October). During each day, we collocate SEVIRI data with A-Train sensors to validate SEVIRI-derived AAC. We also examine the spatial coverage of pristine clouds, cloud-free aerosols over ocean, and aerosols above clouds at various timescales over the southeast Atlantic. Uncertainty analyses of aerosol properties, cloud properties, and their height distributions based on radiative transfer calculations will be discussed.