Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 9 20 2009 10.5194/acp-9-7825-2009 http://www.atmos-chem-phys.net/9/7825/2009/ http://www.atmos-chem-phys.net/9/7825/2009/acp-9-7825-2009.html http://www.atmos-chem-phys.net/9/7825/2009/acp-9-7825-2009.pdf 7825 7845 2009-10-20 Orographic cirrus in a future climate H. Joos hanna.joos@env.ethz.ch P. Spichtinger U. Lohmann Institute for Atmospheric and Climate Science, ETH Zurich, Universitaetsstrasse 16, 8092 Zurich, Switzerland A cloud resolving model (CRM) is used to investigate the formation of orographic cirrus clouds in the current and future climate. The formation of cirrus clouds depends on a variety of dynamical and thermodynamical processes, which act on different scales. First, the capability of the CRM in realistically simulating orographic cirrus clouds has been tested by comparing the simulated results to aircraft measurements of an orographic cirrus cloud. 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