We present a method for deriving the radiative effects of absorbing aerosols in cloudy scenes from satel- lite retrievals only. We use data of 20052007 from various passive sensors aboard satellites of the A-Train constella- tion. The study area is restricted to the tropical- and subtrop- ical Atlantic Ocean. To identify the dependence of the local planetary albedo in cloudy scenes on cloud liquid water path and aerosol optical depth (AOD), we perform a multiple lin- ear regression. The OMI UV-Aerosolindex serves as an in- dicator for absorbing-aerosol presence. In our method, the aerosol influences the local planetary albedo through direct- (scattering and absorption) and indirect (Twomey) aerosol ef- fects. We find an increase of the local planetary albedo (LPA) with increasing AOD of mostly scattering aerosol and a de- crease of the LPA with increasing AOD of mostly absorbing aerosol. These results allowus to derive the direct aerosol ef- fect of absorbing aerosols in cloudy scenes, with the effect of cloudy-scene aerosol absorption in the tropical- and subtrop- ical Atlantic contributing (+21.211.1)103Wm2 to the global top of the atmosphere radiative forcing.
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