chemical sources and sinks of ocs in the lower atmosphere of venus
DESCRIPTION
Chemical Sources and Sinks of OCS in the Lower Atmosphere of Venus. Yuk L. Yung M. C. Liang, California Institute of Technology [email protected] EGU Meeting 2008. Important Processes in the Atmosphere of Venus. Catalytic Chemical Cycles Heterogeneous Chemistry - PowerPoint PPT PresentationTRANSCRIPT
Chemical Sources and Sinks of OCS in the Lower Atmosphere of Venus
Yuk L. YungM. C. Liang,
California Institute of [email protected]
EGU Meeting2008
Important Processes in the Atmosphere of Venus
• Catalytic Chemical Cycles
• Heterogeneous Chemistry
• Middle Atmosphere Circulation
• OCS as tracers of chemistry and dynamics
Venus model description
• Two-dimensional Caltech/JPL KINETICS chemical transport model
• Solve continuity equation for 24 species with ~200 chemical reactions (subset of Mills’)
Role of circulation
• Affect the upward flux of OCS from the surface
• Reduce OCS abundances at high latitudes
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S2 OCS
S3 S4S8
hv
S
S
hv
hv
hv
hv
CO
S4
S2
S
S3
S4
hv S
Conclusions
• Scale height of OCS cannot be explained by photolysis alone
• Photosensitized dissociation of OCS via polysulfur photochemistry
• Integrated destruction rate of OCS is 23,000 Tg- S/yr [Earth = 10 Tg-S/yr]
Acknowledgements
• NASA and ESA• P. Drossart• R. L. Shia• K. Baines• D. Crisp• C. Lee• X. Jiang • B. Bezard• E. Marq
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