Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 3 2007 10.5194/acpd-7-8141-2007 http://www.atmos-chem-phys-discuss.net/7/8141/2007/ http://www.atmos-chem-phys-discuss.net/7/8141/2007/acpd-7-8141-2007.html http://www.atmos-chem-phys-discuss.net/7/8141/2007/acpd-7-8141-2007.pdf 8141 8158 2007-06-11 The effect of H₂O adsorption on cloud-drop activation of insoluble particles: a theoretical framework R. Sorjamaa riikka.sorjamaa@uku.fi A. Laaksonen University of Kuopio, Department of Physics, P.O. Box 1627, 70211 Kuopio, Finland Finnish Meteorological Institute, P.O. Box 503, 00101 Helsinki, Finland Cloud droplet activation of wettable insoluble compounds has been studied theoretically by assuming droplet growth to happen through multilayer adsorption. The idea is to include an adsorption isotherm in Köhler theory instead of the solute term. 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