HR: 15:25h
AN: A43E-08 [Abstracts]
TI: Climate Response of Direct Radiative Forcing of Anthropogenic Black Carbon}
AU: * Chung, S H
EM: serenac@its.caltech.edu
AF: California Institute of Technology, 1200 E. California Blvd
MC 210-41, Pasadena, CA 91125
United States
AU: Seinfeld, J H
EM: seinfeld@caltech.edu
AF: California Institute of Technology, 1200 E. California Blvd
MC 210-41, Pasadena, CA 91125
United States
AB:
The equilibrium climate effect of direct radiative forcing of anthropogenic black carbon (BC) is examined by 100-year
simulations in the Goddard Institute for Space Studies General Circulation Model II-prime with a mixed-layer ocean model.
Anthropogenic BC is predicted to raise globally and annually averaged equilibrium surface air temperature by 0.20 K if BC is
assumed to be externally mixed. The predicted increase is significantly greater in the Northern Hemisphere (0.29 K) than in
the Southern Hemisphere (0.11 K). If BC is assumed to be internally mixed with the present-day level of sulfate aerosol, the
predicted annual mean surface temperature increase rises to 0.37 K globally, 0.54 K for the Northern Hemisphere, and 0.20 K
for the Southern Hemisphere. In the tropics and midlatitudes,
the largest temperature increase is predicted to occur in the upper troposphere. Direct radiative forcing of anthropogenic
BC is also predicted to lead to a change of precipitation patterns in the tropics; precipitation is predicted to increase
between 0 and 20$\deg$N and decrease between 0 and 20$\deg$S. If BC is assumed to be internally mixed with sulfate instead of
externally mixed, the change in precipitation pattern is enhanced. The change in precipitation pattern is not predicted to
alter the global burden of BC significantly because that occurs predominantly in regions removed from BC sources.
DE: 1610 Atmosphere (0315, 0325)
DE: 1620 Climate dynamics (3309)
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting