ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-8-15-2008 Aerosols' influence on the interplay between condensation, evaporation and rain in warm cumulus cloud Altaratz O. 1 Koren I. 1 Reisin T. 2 Kostinski A. 3 Feingold G. 4 Levin Z. 5 Yin Y. 6 Department of Environmental Sciences, Weizmann Institute, Rehovot, Israel Soreq Nuclear Research Center, Yavne, Israel Department of Physics, Michigan Technological University, Houghton, Michigan, USA NOAA Earth System Research Laboratory, Boulder, Colorado, USA Department of Geophysics and Planetary Sciences, Tel Aviv University, Tel Aviv, Israel Department of Applied Meteorology, Nanjing University Information Science & Technology, Nanjing, China 04 01 2008 8 1 15 24 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/8/15/2008/acp-8-15-2008.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/8/15/2008/acp-8-15-2008.pdf

A numerical cloud model is used to study the influence of aerosol on the microphysics and dynamics of moderate-sized, coastal, convective clouds that develop under the same meteorological conditions. The results show that polluted convective clouds start their precipitation later and precipitate less than clean clouds but produce larger rain drops. The evaporation process is more significant at the margins of the polluted clouds (compared to the clean cloud) due to a higher drop surface area to volume ratio and it is mostly from small drops. It was found that the formation of larger raindrops in the polluted cloud is due to a more efficient collection process.

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