Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 8 5 2008 10.5194/acp-8-1225-2008 http://www.atmos-chem-phys.net/8/1225/2008/ http://www.atmos-chem-phys.net/8/1225/2008/acp-8-1225-2008.html http://www.atmos-chem-phys.net/8/1225/2008/acp-8-1225-2008.pdf 1225 1230 2008-03-04 Does the threshold representation associated with the autoconversion process matter? H. Guo hguo@bnl.gov Y. Liu J. E. Penner Atmospheric Science Division, Brookhaven National Laboratory, Upton, NY, USA Department of Atmospheric, Oceanic and Space Sciences, the University of Michigan, Ann Arbor, MI, USA Different ad hoc threshold functions associated with the autoconversion process have been arbitrarily used in atmospheric models. However, it is unclear how these ad hoc functions impact model results. 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