HR: 11:04h
AN: A22D-03    [Abstracts]
TI: Implications of cloud resolving model simulations of aerosol indirect effects on cloud radiative properties and precipitation to global climate
AU: * Cotton, W R
EM: cotton@atmos.colostate.edu
AF: Colorado State University, Dept. of Atmospheric Science Colorado State University, Fort Collins, CO 80523,
AB: There is mounting evidence from my group's modeling studies of aerosol impacts on cloud radiative properties and precipitation as well as a number of other research groups, that once the precipitation process is modified, the cloud response is highly nonlinear. In some cases the clouds may respond to pollution aerosols by becoming optically thicker and raining less while in other cases just the opposite happens. This is true for marine stratocumulus clouds, tradewind cumuli, and cumulonimbi. In this talk I provide examples of such responses. The implication of this work is that cloud responses to pollution aerosols are very difficult to parameterize realistically in general circulation models and moreover that those responses are quite unpredictable at the present time. This is not to say that pollution aerosol impacts on the climate system is not important, but that quantifying that impact is a great deal more challenging than we have been lead to believe.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting