Fluid flow at the top of Jupiter's dynamo region
File(s)
Accepted version
Author(s)
Sharan, Shivangi
Type
Journal Article
Abstract
The magnetic main field (MF) and secular variation (SV) models for Jupiter can be used to gain insights about the internal dynamo and the flow that drives the field. We use two such models computed from Juno observations up to spherical harmonic degrees 16 and 8 for the MF and SV, respectively. We solve the radial magnetic induction equation in the frozen-flux approximation, at the dynamo region outer boundary assuming zero radial velocity for four large-scale physical flow assumptions- unconstrained, toroidal, tangentially geostrophic and columnar. We find flows with root mean square velocity varying between 100 and 400 km/yr (0.3-1.3 cm/s) when the dynamo region spherical boundary is taken at 0.83 Jupiter radius. Equatorially symmetric, toroidal and non-zonal velocity components are larger than the anti-symmetric, poloidal and zonal components, respectively, for almost all cases. Toroidal and tangentially geostrophic flows display similar velocity values and patterns, despite relying on different physical assumptions. The four inverted solutions indicate that the Jovian interior has dominant eastward flows near
the Great Blue Spot, in agreement with previous studies. In addition, our more complex flow models shed light on some new features such as a large non-zonal component,
meridional flows in the southern hemisphere and field-aligned flows in the north. Finally, our unconstrained flow solution suggests upwelling near the south pole, consistent withn thermal wind theory.
the Great Blue Spot, in agreement with previous studies. In addition, our more complex flow models shed light on some new features such as a large non-zonal component,
meridional flows in the southern hemisphere and field-aligned flows in the north. Finally, our unconstrained flow solution suggests upwelling near the south pole, consistent withn thermal wind theory.
Date Acceptance
2025-12-03
Citation
Journal of Geophysical Research: Planets
ISSN
2169-9097
Publisher
American Geophysical Union
Journal / Book Title
Journal of Geophysical Research: Planets
Copyright Statement
Copyright This paper is embargoed until publication. Once published the Version of Record (VoR) will be available on immediate open access.
License URL
Publication Status
Accepted