Aerosol Effects on the Stratocumulus and Evaluations of Microphysics

  • Yuan WangEmail author
Part of the Springer Theses book series (Springer Theses)


This study aims at assessing the aerosol effects on the maritime stratocumulus (Sc) clouds and improving the cloud microphysical schemes for more realistic simulations of aerosol and cloud properties in regional and climate models. The double-moment Morrison bulk microphysical scheme presently implemented in the WRF model (Morrison et al. 2005) has been modified by replacing the prescribed aerosols in the original bulk scheme (Bulk-OR) with a prognostic double-moment aerosol representation (Bulk-2M). Furthermore, the impacts of the parameterizations of droplet diffusional growth and autoconversion and the selection of the embryonic raindrop radius on the performance of the bulk microphysical scheme have also been evaluated by the field observations and spectral bin microphysics (SBM) simulations. A maritime Sc system has been investigated over the Southeast Pacific Ocean from an international program, VAMOS Ocean-Cloud-Atmosphere-Land Study (VOCALS), the major goal of which is to advance the scientific understanding of land-ocean-atmosphere coupled system over the Southeast Pacific region. The warm Sc system is selected because the microphysical and dynamical processes are relatively simple to identify the differences between bulk and SBM microphysics and to evaluate the causes and effects of different treatments in the microphysics.


Aerosol indirect effect Cloud microphysics Stratocumulus clouds 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.California Institute of TechnologyPasadenaUSA

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