HR: 09:50h
AN: AE21A-10    [Abstracts]
TI: The Effects of Lightning-Produced NO$_x$ and its Vertical Distribution on Atmospheric Chemistry: Sensitivity Simulations with the Model of Atmospheric Chemistry and Transport, Max-Planck Institute for chemistry version (MATCH-MPIC)
AU: * Labrador, L J
EM: lorenzo@mpch-mainz.mpg.de
AF: Max-Planck Institute for Chemistry, P. O. Box 3060, Mainz, D-55020 Germany
AU: von Kuhlmann, R
EM: kuhlmann@mpch-mainz.mpg.de
AF: Max-Planck Institute for Chemistry, P. O. Box 3060, Mainz, D-55020 Germany
AU: Lawrence, M G
EM: lawrence@mpch-mainz.mpg.de
AF: Max-Planck Institute for Chemistry, P. O. Box 3060, Mainz, D-55020 Germany
AB: The impact of different assumptions concerning the source magnitude as well as the vertical placement of lightning-produced nitrogen oxides is studied using the global chemistry transport model MATCH-MPIC. The responses of NO$_x$, O$_3$, OH, HNO$_3$ and peroxyacetyl-nitrate (PAN) are investigated. A marked sensitivity to both parameters was found. NO$_x$ burdens globally can be enhanced up to 100% depending on the vertical placement and source magnitude strength. In all cases, the largest enhancements occur in the tropical upper troposphere, where lifetimes of most trace gases are longer and where they thus become more susceptible to long-range transport by long-range circulation patterns. Comparison with observations indicate that the 0 and 20 Tg/yr(N) production rates of NO$_x$ from lightning are too low and too high, respectively. However, no single intermediate production rate or vertical distribution can be singled out as best fitting the observations due to the large scatter in the datasets. This underscores the need for further measurement campaigns in key regions, particularly in the tropics.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0320 Cloud physics and chemistry
DE: 0322 Constituent sources and sinks
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric and Space Electricity [AE]
MN: 2004 AGU Fall Meeting