Lightning generation in moist convective clouds and constraints on the water abundance in Jupiter

Abstract

Recent Juno observations have greatly extended the temporal and spatial coverage of lightning detection on Jupiter. We use these data to constrain a model of moist convection and lightning generation in Jupiter's atmosphere, and derive a roughly solar abundance of water at the base of the water cloud. Shallow lightning, observed by Juno (Becker et al., 2020, Nature, 584, 55-58) and defined as flashes originating at altitudes corresponding to pressure less than 2 bars, is reproduced, as is lightning at a deeper range of pressures, including those below the water cloud base. It is found that the generation of lightning requires ammonia to stabilize liquid water at altitudes corresponding to sub-freezing temperatures. We find a range of local water abundances in which lightning is possible, including subsolar values of water--consistent with other determinations of deep oxygen abundance.

47 pages, 7 figures, to be published in Journal of Geophysical Research - Planets

References in corpus (4)

• Comparing Jupiter interior structure models to Juno gravity measurements and the role of a dilute core
• The water abundance in Jupiter's equatorial zone
• Simulating Non-hydrostatic atmospheres on Planets (SNAP): formulation, validation and application to the Jovian atmosphere
• New Insights on Jupiter's Deep Water Abundance from Disequilibrium Species

Cited by in corpus (1)

• A subsolar oxygen abundance or a radiative region deep in Jupiter revealed by thermochemical modelling