Previous abstract Next abstract
Reported preliminary observational results from the impact of the Shoemaker-Levy 9 impacts with Jupiter reveal an unexpected lack of water and an abundance of sulfur-bearing species, especially hydrogen sulfide. One early interpretation involved the notion that impactors reached down to the ammonium hydrosulfide cloud layer but not the water cloud. We construct one-dimensional models of Jovian cloud structure and moist convective processes to assess the plausibility of such a picture and to consider alternative ones. The following results are obtained: (1) In order to dredge up larger amounts of hydrogen sulfide moleculesversus water, the bolides must predominently stir up a very narrow region withinthe atmosphere of Jupiter, less than 20 km in vertical extent. This is implausible. (2) An alternative model devolves from the result that the water cloud is subject to vigorous moist convection in contrast to the overlying ammonium hydrosulfide and ammonia layers, based on our momentum-balance plume models. This allows water to be heterogeneously distributed in the horizontal direction to a much greater extent than the hydrosulfide clouds, with water-rich upwelling plumes occupying a relatively small area of the disk. It is therefore possible that the bolides dredged up material from the dryer, sinking parts of the Jovian disk, leading to a depressed oxygen-to-sulfur ratio in the material observed spectroscopically. Implications for interpretation of Galileo probe water measurements are potentially important and will be outlined.
Tuesday program listing