Numerical Modeling of Moist Convection in Jupiter's Atmosphere
Abstract
We developed a two-dimensional numerical model of Jupiter's cloud convection that incorporates condensation of H2O and NH3 and the production reaction of NH4SH, and investigated the dependency of vertical cloud structure and convective motion on the abundances of condensible volatiles. Radiative forcing model is given as a function of height to drive the convective motion. When the deep abundances of condensible volatiles are larger than 1 times solar, convective motion in the model tend to be separated at the H2O condensation level, but the NH3 condensation level and the NH4SH reaction level don't act as a stationary dynamical boundary. On the other hand, when the abundances of condensible volatiles are taken at 0.1 times solar, even H2O condensation level don't act as a stationary dynamical boundary, and downdraft takes dry air from upper levels to several ten bars level. When the abundances of condensible volatiles are taken at 5 or 10 times solar, moist convection occurs intermittently. In the active period, H2O and NH4SH cloud particles in strong convective clouds is advected above the NH3 condensation level. This single layered structure is in significant contrast to the classical "three layered" cloud structure suggested by one-dimensional thermodynamical models. In the quiet period, two separated cloud layer develop: the lower one contains H2O and NH4SH cloud particles, and upper one consists of the NH3 cloud.We developed a two-dimensional numerical model of Jupiter's cloud convection that incorporates condensation of H2O and NH3 and the production reaction of NH4SH, and investigated the dependency of vertical cloud structure and convective motion on the abundances of condensible volatiles. Radiative forcing model is given as a function of height to drive the convective motion. When the deep abundances of condensible volatiles are larger than 1 times solar, convective motion in the model tend to be separated at the H2O condensation level, but the NH3 condensation level and the NH4SH reaction level don't act as a stationary dynamical boundary. On the other hand, when the abundances of condensible volatiles are taken at 0.1 times solar, even H2O condensation level don't act as a stationary dynamical boundary, and downdraft takes dry air from upper levels to several ten bars level. When the abundances of condensible volatiles are taken at 5 or 10 times solar, moist convection occurs intermittently. In the active period, H2O and NH4SH cloud particles in strong convective clouds is advected above the NH3 condensation level. This single layered structure is in significant contrast to the classical "three layered" cloud structure suggested by one-dimensional thermodynamical models. In the quiet period, two separated cloud layer develop: the lower one contains H2O and NH4SH cloud particles, and upper one consists of the NH3 cloud.
- Publication:
-
Planetary Atmospheres
- Pub Date:
- 2007
- Bibcode:
- 2007plat.work..122S