HR: 1340h
AN: A53A-0141    [Abstracts]
TI: Aerosol-cloud Interactions During 1980-2000 With A Coupled Climate-aerosol Model
AU: * Wang, M
EM: minghuai@umich.edu
AF: Department of Atmospheric, Oceanic, and Space Sciences University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143 United States
AU: Penner, J E
EM: penner@umich.edu
AF: Department of Atmospheric, Oceanic, and Space Sciences University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143 United States
AU: Liu, X
EM: xhliu@umich.edu
AF: Department of Atmospheric, Oceanic, and Space Sciences University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143 United States
AB: Aerosol indirectly affects the climate by modifying the cloud. Firstly, as CCN, larger aerosol number concentration leads to larger cloud number concentration and smaller cloud droplets, which increase the cloud optical depth (1st indirect effect), and surpass the precipitation (2nd indirect effect). Secondly, the absorption of aerosol will decrease the cloud cover (semi-indirect effect). A series of 20-year simulations of a coupled climate-aerosol model (the NCAR CAM3 climate model and the LLNL/Umich IMPACT aerosol model) with the historical SST, sea ice and aerosol emission are used to investigate the different effects of aerosol on the climate during 1980-2000. A prognostic cloud number concentration equation is added to CAM3 to investigate aerosol-cloud interaction. The semi-indirect effect, the 1st indirect effect, and the 2nd indirect effect are checked in the series of simulations. The temporal change of the cloud fields and the radiative fields are analyzed. The model results are compared with the cloud effective radius and other cloud fields from the AVHRR satellite during the same time period.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005