HR: 0800h
AN: A51B-0044    [Abstracts]
TI: Sensitivity of Global Tropospheric Ozone and OH to Meteorological Fields and Other Variables
AU: * Wu, S
EM: wu18@fas.harvard.edu
AF: Harvard University, 29 Oxford Street, Cambridge, MA 02138 United States
AU: Jacob, D J
EM: djacob@fas.harvard.edu
AF: Harvard University, 29 Oxford Street, Cambridge, MA 02138 United States
AU: Mickley, L J
EM: ljm@io.as.harvard.edu
AF: Harvard University, 29 Oxford Street, Cambridge, MA 02138 United States
AB: A global 3-D model of tropospheric chemistry (GEOS-Chem) is used to examine the sensitivity of tropospheric ozone and OH to meteorological fields and other variables including NOx emission, isoprene emission and stratosphere-troposphere exchange (STE). Meteorological fields from 3 different models, namely GEOS_3, GEOS_4 and GISS GCM (3 years), are used to drive GEOS-Chem. The global photochemical production of ozone varies from 4250 to 4700 Tg O3 yr-1 depending on the meteorological fields used. It is also very sensitive to NOx emission, especially from lightning; a 25% increase of NOx emissions from anthropogenic sources and lightning (5.9 Tg N yr-1 and 1.2 Tg N yr-1 respectively in our model) results in an increase of 3.6% and 4.2% respectively for global ozone photochemical production. Globally STE and isoprene emission have little influence on the photochemical production and loss of ozone although regionally they may have large effects. Tropospheric OH is very sensitive to lightning NOx and isoprene emission; a 25% increase of NOx emission from lightning enhances the global OH by 5.3% and a 25% decrease (100 Tg C yr-1 in our model) of isoprene emission results in 4.6% increase of global OH.
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005