Impact of surface emissions to the zonal variability of tropical tropospheric ozone and carbon monoxide for november 2004

K. W. Bowman (1) , D. Jones (2) , J. Logan (3) , H. Worden (1) , F. Boersma (3) , R. Chang (4) , S. Kulawik (1) , G. Osterman (1) , J. Worden (1)

1 JPL - Jet Propulsion Laboratory
2 Department of Physics [Toronto]
3 SEAS - Harvard John A. Paulson School of Engineering and Applied Sciences
4 Department of Chemistry

The chemical and dynamical processes governing the zonal variability of tropical tropospheric ozone and carbon monoxide are investigated for November 2004 using satellite observations, in-situ measurements, and chemical transport models in conjunction with inverse-estimated surface emissions. Vertical ozone profile estimates from the Tropospheric Emission Spectrometer (TES) and ozone sonde measurements from the Southern Hemisphere Additional Ozonesondes (SHADOZ) network show the so-called zonal "wave-one" pattern, which is characterized by peak ozone concentrations (70?80 ppb) centered over the Atlantic, as well as elevated concentrations of ozone over Indonesia and Australia (60?70 ppb) in the lower troposphere. Observational evidence from TES CO vertical profiles and Ozone Monitoring Instrument (OMI) NO₂ columns point to regional surface emissions as an important contributor to the elevated ozone over Indonesia. This contribution is investigated with the GEOS-Chem chemistry and transport model using surface emission estimates derived from an optimal inverse model, which was constrained by TES and Measurements Of Pollution In The Troposphere (MOPITT) CO profiles (Jones et al., 2007). These a posteriori estimates, which were over a factor of 2 greater than climatological emissions, reduced differences between GEOS-Chem and TES ozone observations by 30?40% and led to changes in GEOS-Chem upper tropospheric ozone of up to 40% over Indonesia. The remaining residual differences can be explained in part by upper tropospheric ozone produced from lightning NO_x in the South Atlantic. Furthermore, model simulations from GEOS-Chem indicate that ozone over Indonesian/Australian is more sensitive to changes in surface emissions of NO_x than ozone over the tropical Atlantic.

Domaines: Océan, Atmosphère

K. W. Bowman, D. Jones, J. Logan, H. Worden, F. Boersma, et al.. Impact of surface emissions to the zonal variability of tropical tropospheric ozone and carbon monoxide for november 2004. Atmospheric Chemistry and Physics Discussions, 2008, 8 (1), pp.1505-1548. ⟨hal-00303272⟩