PI: Celine Guervilly

Spectacular cyclonic structures were discovered in the polar regions of Jupiter by NASA’s Juno spacecraft in 2016. These polar cyclones are vast in size, long-lived, and arranged in clusters of five and eight circumpolar vortices around a larger polar vortex at the south and north poles respectively. This arrangement has essentially remained unchanged over nearly a decade of observation. The origin of these polar cyclones has remained a mystery so far. The goal of our study is to explain the formation, structure and saturation of these large-scale vortices, and how they interact with the convective layer of Jupiter’s atmosphere. The Jovian atmosphere has a low Prandtl number (ratio of momentum diffusivity to thermal diffusivity). At this value, convective flows become oscillatory at the onset of rotating convection, and so part of the study is to determine how this impacts the LSVs. We perform 3D, local box simulations to model rapidly-rotating, Boussinesq convection at low Prandtl numbers.

Figure 1 – Kinetic energy of the flow in an horizontal plane at a given height from one of 3D simulations of rapidly-rotating, Boussinesq convection.