A new convective parameterization applied to Jupiter: implications for water abundance near the $24^\circ$ N region

TL;DR

This study introduces a new convective parameterization in a GCM to better understand water-related convective storms on Jupiter, revealing water abundance limits near the $24^\u00b0$ N jetstream.

Contribution

The paper develops a sub-grid scale moist convective module for the EPIC GCM, applied specifically to Jupiter's atmosphere at $24^\u00b0$ N, to analyze water's role in storm formation.

Findings

Convective potential correlates with water amount.

Vertical fluxes are strongly linked to water content.

Water abundance near the jet is limited to twice the solar [O/H] ratio.

Abstract

Jupiter's atmosphere features a variety of clouds that are formed from the interplay of chemistry and atmospheric dynamics, from the deep red color of the Great Red Spot to the high altitude white ammonia clouds present in the zones (bright bands in Jupiter's atmosphere). Beneath these upper level clouds, water condensation occurs, and sporadically leads to the formation of towering convective storms, driven by the release of large amounts of latent heat. These storms result in a widespread disruption of the cloud and dynamical structure of the atmosphere at the latitude where they form, making the study of these events paramount in understanding the dynamics at depth, and the role of water in the jovian atmosphere. In this work, we use the Explicit Planetary hybrid-Isentropic Coordinate (EPIC) General Circulation Model (GCM) to study the jovian atmosphere, with a focus on moist convective storm formation from water condensation. We present the addition of a sub-grid scale moist convective module to model convective water cloud formation. We focus on the $24^\circ$ N latitude, the location of a high speed jetstream, where convective upwellings have been observed every 4-5 years. We find that the potential of convection, and vertical mass and energy flux of the atmosphere is strongly correlated with the amount of water, and we determine an upper limit of the amount of water in the the region surrounding the jet as twice the solar [O/H] ratio.