ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-12-1003-2012 A hybrid bin scheme to solve the condensation/evaporation equation using a cubic distribution function Dinh T. 1 Durran D. R. 1 Department of Atmospheric Sciences, University of Washington, Seattle, Washington 98195, USA 20 01 2012 12 2 1003 1011 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/12/1003/2012/acp-12-1003-2012.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/12/1003/2012/acp-12-1003-2012.pdf

A computationally efficient method is proposed to replace the piecewise linear number distribution in a hybrid bin scheme with a piecewise cubic polynomial. When the linear distribution is replaced by a cubic, the errors generated in solutions to the condensation/evaporation equation are reduced by a factor of two to three. Alternatively, using the cubic distribution function allows reducing the number of bins by 20 ± 5% when solving the condensation/evaporation problem without sacrificing accuracy.

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