HR: 1340h
AN: A13B-0907 [Abstracts]
TI: Sensitivity of Global Ozone and PM2.5 Concentrations to Climate Change
AU: * Racherla, P N
EM: pavanracherla@cmu.edu
AF: Carnegie Mellon University,
Dept of Engineering and Public Policy,
Dept of Mechanical Engineering, Baker Hall 128-C, Pittsburgh, PA 15213
United States
AU: Adams, P J
EM: peteradams@cmu.edu
AF: Carnegie Mellon University,
Dept of Civil and Environmental Engineering,
Dept of Engineering and Public Policy, Porter Hall 118-L, Pittsburgh, PA 15213
United States
AB:
An integrated global model of climate, tropospheric gas-phase
chemistry and aerosols has been used to investigate the sensitivity of
global O3 and PM2.5 concentrations to climate change.
Representative future climate has been imposed on the system using
ocean boundary conditions corresponding to the IPCC SRES A2 scenario
for the 2050s decade.
The simulated future climate corresponds to a 1.7 K increase in the
global annual-average surface temperature and a 13% increase in the
tropospheric water vapor burden.
Tropospheric O3 burden and lifetime in the future climate run
decrease due to increased loss rates by O3 photolysis in the
presence of water vapor, which more than compensates for the increased
O3 chemical production associated with increased temperatures. The
predicted changes in surface O3 correlate strongly with the changes
in local water vapor concentrations, and to a lesser extent, the
changes in local O3 chemical production.
The global burdens of PM2.5 species in the future climate run
decrease due to increased wet deposition loss rates, associated with
increased global annual-average precipitation. Regional-scale changes
in the predicted surface PM2.5 concentrations depend upon the
changes in the regional precipitation, the processes leading to the
formation of the species and transport. The robustness of the
predicted regional PM2.5 changes is strongly dependent upon a
competition between regional-scale precipitation changes, production
rates, and gas-aerosol partitioning.
DE: 1630 Impacts of global change (1225)
DE: 3305 Climate change and variability (1616, 1635, 3309, 4215, 4513)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005