Exploring the role of water in Jupiter's weather layer: Implication to the evolution and interior of gas giants
Abstract
Water is the major carrier of oxygen in Jupiter's atmosphere. Its abundance sheds light on the evolution and formation history of Jupiter and our solar system. Here, we study the role of water, particularly on the heat transport and thermal structure, in Jupiter's weather layer. The fundamental mechanism of heat transport in a giant planet is thermal convection, in which warm air rises and cold air sinks. Evolution models of giant planets all presumed that convective heat transport efficiently delivers the heat from the interior to the photosphere, where the heat is radiated to space. However, the condensation and mass loading effect of water prohibit thermal convection. Convective heat transport becomes inefficient or even fails in the stably stratified region of the planet, known as the problem of convective inhibition. Here, we perform high-resolution 3D cloud-resolving simulations of moist convection in Jupiter's atmosphere. We found the nature of moist convection to be three-fold. First, the stable layer induced by the condensation of water prohibits convection, and convective heat transport for an extensive range of deep water abundances is 1-to-3 times solar. Second, raining and its subsequent evaporation/boiling is the key to relaying the heat transport across the stably stratified layer. Third, shallow convection triggers deep convection. They are disjointed by the stable layer at all times if the deep water abundance is greater than 3 times solar. Deep convection lags the cloud-level convection by about a few hours to half a day. The combined ground-based monitoring of cloud-level convective storms and the current Juno microwave remote sensing of deeper layers may verify the connection between the disjointed convection on Jupiter. Our findings also suggest that the water stable layer forms a persistent superadiabatic layer that substantially affects the observational retrieval and changes our understanding of the interior and evolution of Jupiter. The interior temperature could be warmer by about 5 K, which leads to a core that can sustain more metallicity. Jupiter may cool slower than in the scenario without taking water vapor into account. The impact of condensable volatiles on the evolution of planets can apply to other objects with hydrogen envelopes.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.P25B..04G