Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Atmos. Chem. Phys., 14, 11935-11948, 2014
http://www.atmos-chem-phys.net/14/11935/2014/
doi:10.5194/acp-14-11935-2014
© Author(s) 2014. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
13 Nov 2014
The effects of aerosols on water cloud microphysics and macrophysics based on satellite-retrieved data over East Asia and the North Pacific
T. Michibata1,3, K. Kawamoto2, and T. Takemura3 1Department of Earth System Science and Technology, Kyushu University, Fukuoka, Japan
2Graduate School of Fisheries Science and Environmental Studies, Nagasaki University, Nagasaki, Japan
3Research Institute for Applied Mechanics, Kyushu University, Fukuoka, Japan
Abstract. This study examines the characteristics of the microphysics and macrophysics of water clouds from East Asia to the North Pacific, using data from active CloudSat radar measurements and passive MODerate-resolution Imaging Spectroradiometer (MODIS) retrievals. Our goals are to clarify differences in microphysics and macrophysics between land and oceanic clouds, seasonal differences unique to the midlatitudes, characteristics of the drizzling process, and cloud vertical structure. In pristine oceanic areas, fractional occurrences of cloud optical thickness (COT) and cloud droplet effective radius (CDR) increase systematically with an increase in drizzle intensity, but these characteristics of the COT and CDR transition are less evident in polluted land areas. In addition, regional and seasonal differences are identified in terms of drizzle intensity as a function of the liquid water path (LWP) and cloud droplet number concentration (Nc). The correlations between drizzle intensity and LWP, and between drizzle intensity and Nc, are both more robust over oceanic areas than over land areas. We also demonstrate regional and seasonal characteristics of the cloud vertical structure. Our results suggest that aerosol–cloud interaction mainly occurs around the cloud base in polluted land areas during the winter season. In addition, a difference between polluted and pristine areas in the efficiency of cloud droplet growth is confirmed. These results suggest that water clouds over the midlatitudes exhibit a different drizzle system to those over the tropics.

Citation: Michibata, T., Kawamoto, K., and Takemura, T.: The effects of aerosols on water cloud microphysics and macrophysics based on satellite-retrieved data over East Asia and the North Pacific, Atmos. Chem. Phys., 14, 11935-11948, doi:10.5194/acp-14-11935-2014, 2014.
Publications Copernicus
Download
Short summary
This study examines the characteristics of the microphysics and macrophysics of water clouds from East Asia to the North Pacific, using data from CloudSat and MODIS retrievals. We demonstrate regional and seasonal characteristics of the cloud vertical structure and found a difference in the “contoured frequency by optical-depth diagram” (CFODD) between the pristine oceanic area and the polluted land area, implying aerosol-–cloud interaction.
This study examines the characteristics of the microphysics and macrophysics of water clouds...
Share