ACP Atmospheric Chemistry and Physics ACP Atmos. Chem. Phys. 1680-7324 Copernicus Publications Göttingen, Germany 10.5194/acp-9-5751-2009 A simple model for cloud radiative forcing Corti T. 1 Peter T. 1 Institute for Atmospheric and Climate Science, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland 12 08 2009 9 15 5751 5758 Copyright: © 2009 T. Corti 2009 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/articles/9/5751/2009/acp-9-5751-2009.html The full text article is available as a PDF file from https://acp.copernicus.org/articles/9/5751/2009/acp-9-5751-2009.pdf

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%. We demonstrate the usefulness of our model using the example of tropical cirrus clouds. We conclude that possible applications for the model include the convenient estimate of cloud radiative forcing for a wide range of conditions, the evaluation of the sensitivity to changes in environmental conditions, and as a tool in education. An online version of the model is available at <a href="http://www.iac.ethz.ch/url/crf"target="_blank">http://www.iac.ethz.ch/url/crf</a>.

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