Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 9 15 2009 10.5194/acp-9-5751-2009 http://www.atmos-chem-phys.net/9/5751/2009/ http://www.atmos-chem-phys.net/9/5751/2009/acp-9-5751-2009.html http://www.atmos-chem-phys.net/9/5751/2009/acp-9-5751-2009.pdf 5751 5758 2009-08-12 A simple model for cloud radiative forcing T. Corti thierry.corti@env.ethz.ch T. Peter Institute for Atmospheric and Climate Science, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland We present a simple model for the longwave and shortwave cloud radiative forcing based on the evaluation of extensive radiative transfer calculations, covering a global range of conditions. The simplicity of the model equations fosters the understanding on how clouds affect the Earth's energy balance. In comparison with results from a comprehensive radiative transfer model, the accuracy of our parameterization is typically better than 20%. 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