CM-SAF high-resolution radiation budget products

Abstract

In this paper the system employed at the Royal Meteorological Institute of Belgium (RMIB) within the Climate Monitoring Satellite Application Facility (CM-SAF) for the production of Top Of the Atmosphere (TOA) radiation budget components is described. One of the goals of the CM-SAF is to provide consistent TOA and surface radiation budget components and cloud properties at high spatial resolution and on an approximate equal area grid for a region that covers at least Europe and part of the North Atlantic Ocean. The TOA radiation products will be based on data from polar orbiting satellites for northern latitudes, and on data from MSG (METEOSAT Second Generation) for mid latitudes. The instruments used for the reflected solar and emitted thermal flux estimates will be GERB (Geostationary Earth Radiation Budget) and SEVIRI as the geostationary instruments and CERES (Clouds and the Earth's Radiant Energy System) for the non geostationary instruments. Daily means, monthly means and monthly mean diurnal cycles are to be provided. Until MSG fluxes will become available, fluxes from METEOSAT and CERES are used for development. At the TOA the three radiative flux components of incoming solar radiation, reflected solar radiation and emitted thermal radiation will be given. The daily mean GERB and CERES fluxes will be merged to produce a homogenized TOA flux product. The method used for the merging of the TOA fluxes and together with results using currently available input data are shown. The merging consists in the collocation of the two instruments, detection and the removal of the systematic dependencies of the flux estimates on scene type and viewing angles and regridding on a common grid.