Sources of SO and SO2 in the Mesosphere of Venus

Yuk L. Yung, X. Zhang, M. C. Liang, F. P. Mills, D. A. Belyaev

Caltech

EPSC-DPS 2011, NANTES, FRANCE

Belyaev et al. (2011)

Zhang et al. (2011)

SO (H2SO4 Case)

SO2 (H2SO4 Case)

SO3 (H2SO4 Case)

SO (Sx Case)

SO2 (Sx Case)

SO3 (Sx Case)

Conclusion

• A sulfur source is required to explain the SO2 inversion layer above 80 km.

• The evaporation of the aerosols composed of sulfuric acid or polysulfur above 90 km could provide the sulfur source.

• Measurements of SO3 and SO (a1∆→X3∑) emission at 1.7 μm may be the key to distinguish between the two models.

Acknowledgement

• NASA Grant • Venus Express Project

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• Sandor, B. J., et al., 2010, Sulfur chemistry in the Venus mesosphere from SO2 and SO microwave spectra, Icarus 208, 49-60.

• Sandor, B.J., Clancy, R.T., Moriarty-Schieven, G.H., 2011, Upper limits for H2SO4 in the mesosphere of Venus. Icarus. doi:10.1016/j.icarus.2011.03.032.

• Zhang, X., et al., 2011, Sulfur chemistry in the middle atmosphere of Venus. Icarus, doi:10.1016/j.icarus.2011.06.016.