HR: 11:15h
AN: A32B-04    [Abstracts]
TI: Is it okay to treat absorbing aerosols as steady in a climate model?
AU: * Chung, C E
EM: cchung@fiji.ucsd.edu
AF: Scripps Institution of Oceanography, mail code: 0221, La Jolla, CA 92093 United States
AB: Absorbing aerosols are another atmospheric diabatic heating source, and their distribution and amounts fluctuate as circulation and precipitation change. In this study, the author generates two sets of aerosol-induced diabatic heating which are identical in a monthly mean sense. In one set the aerosol distribution and amount are simulated and thus adapt to rapidly-changing circulation and precipitation, while the other set uses steady aerosols. The author coupled Rasch's aerosol wet deposition scheme to the NACR/CCM3, and modified the CCM3 radiation code to include the aerosol-generated diabatic heating. The Indian aerosols are simulated with prescribed aerosol emissions over India. The diabatic heating resulting from this Indian haze increases the precipitation over the haze area. The steady haze heating leads to a larger precipitation increase (larger by about 30%) than the simulated haze heating. In case of the Chinese haze, the simulated and steady haze heatings have about the same amplitude of impact on precipitation. It is also found that the East Asian climate is less sensitive to aerosol heating than the South Asian climate.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0545 Modeling (4255)
DE: 1620 Climate dynamics (0429, 3309)
DE: 1637 Regional climate change
DE: 1807 Climate impacts
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005