ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-457-2011 Influence of convection and aerosol pollution on ice cloud particle effective radius Jiang J. H. 1 Su H. 1 Zhai C. 1 Massie S. T. 2 Schoeberl M. R. 3 Colarco P. R. 4 Platnick S. 4 Gu Y. 5 Liou K.-N. 5 Jet propulsion Laboratory, California Institute of Technology, Pasadena, California, USA National Center for Atmospheric Research, Boulder, Colorado, USA Science and Technology Corporation, Columbia, Maryland, USA NASA Goddard Space Flight Center, Greenbelt, Maryland, USA Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, USA 17 01 2011 11 2 457 463 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/11/457/2011/acp-11-457-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/457/2011/acp-11-457-2011.pdf

Satellite observations show that ice cloud effective radius (<i>r</i><sub>e</sub>) increases with ice water content (IWC) but decreases with aerosol optical thickness (AOT). Using least-squares fitting to the observed data, we obtain an analytical formula to describe the variations of <i>r</i><sub>e</sub> with IWC and AOT for several regions with distinct characteristics of <i>r</i><sub>e</sub>-IWC-AOT relationships. As IWC directly relates to convective strength and AOT represents aerosol loading, our empirical formula provides a means to quantify the relative roles of dynamics and aerosols in controlling <i>r</i><sub>e</sub> in different geographical regions, and to establish a framework for parameterization of aerosol effects on <i>r</i><sub>e</sub> in climate models.

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