Investigating the parameters controlling transport in Jovian stratosphere is important for understanding sources and sinks of aerosols in the upper atmosphere of this giant planet. Since C_2H_6 is the most abundant and stable hydrocarbon in the Jovian stratosphere, we use the Caltech/JPL 2-D photochemical model to treat C_2H_6 as a tracer of dynamical processes. For non-dissipative motion, we adopt the advection by the residual circulation derived from West et al. (1992). Horizontal and vertical diffusive transport by large-scale quasi-geostrophic eddies are included as free parameters in determining the tracer motions. The observation of zonally averaged mixing ratios of C_2H_6 by the University of Texas infrared echelle spectrometer shows enhancement of C_2H_6 in the northern polar region. Therefore, enhanced downward fluxes of C_2H_6 at the upper boundary in the polar regions are treated as another parameter in this model because of the possible formation of hydrocarbons in the ionosphere by auroral chemistry. Comparisons between our model calculations and the observed C_2H_6 zonal mean distribution provide constraints on meridional diffusive transport, vertical transport, and the formation rate of hydrocarbons in upper atmosphere of Jupiter by auroral chemistry.
AAS/Division for Planetary Sciences Meeting Abstracts #30
- Pub Date:
- September 1998