Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 9 6 2009 10.5194/acpd-9-23589-2009 http://www.atmos-chem-phys-discuss.net/9/23589/2009/ http://www.atmos-chem-phys-discuss.net/9/23589/2009/acpd-9-23589-2009.html http://www.atmos-chem-phys-discuss.net/9/23589/2009/acpd-9-23589-2009.pdf 23589 23622 2009-11-05 On the transitions in marine boundary layer cloudiness I. Sandu irina.sandu@zmaw.de B. Stevens R. Pincus Max Planck Institute for Meteorology, Hamburg, Germany University of California at Los Angeles, Los Angeles, California, USA University of Colorado/NOAA Earth System Research Lab, Boulder, Colorado, USA Satellite observations and meteorological reanalysis are used to examine the transition from unbroken sheets of stratocumulus to fields of scattered cumulus, and the processes controlling them, in four subtropical ocean basins. 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