Abstract
The conversion of radiances measured by the METEOSAT visible channel into broadband radiances can be performed as long as the appropriate conversion factors are known. A simple model allowing a spectral description of the optical properties of cloud free atmospheres and land surfaces is used to estimate these conversion factors. A sensitivity study of these factors indicates that a knowledge of the optical properties of the surfaces (described through spectrally averaged albedos and spectral band ratios) is decisive for retrieving broadband conversion factors. A parameterization is proposed which permits estimation of METEOSAT conversion factors for radiation budget calculations.
