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(Junjun Liu and Tapio Schneider, 2010)

We have carried out the first 3D simulations of all four giant planets (Jupiter, Saturn, Uranus, Neptune) with closed energy and angular momentum balances that are consistent with observations (Liu and Schneider 2010). The simulations reproduce many large-scale features of the observed flows, such as equatorial superrotation on Jupiter and Saturn and equatorial subrotation on Uranus and Neptune.

The simulations resolve the flow in the upper atmospheres of the giant planets, with implicit links to the (convective) flow, mean meridional circulations and (likely magnetohydrodynamic) dissipation mechanisms at depth. Below are animations of the zonal wind and vorticity at the level in the model that corresponds roughly to the estimated level of the cloud tops from which the observed flows are inferred.

Coherent vortices form in these simulations and are recognizable in the vorticity fields. They are particularly large in the polar regions, where the largest vortices are cyclonic: see the polar projections of the vorticity in the Jupiter and Saturn simulations. Similar cyclonic vortices have recently been observed by the Juno mission.

Earlier we had carried out simulations of Jupiter with the same model (Schneider and Liu 2009), but with slightly different choices of dissipation parameters (which are poorly constrained by data). This leads to weaker and narrower jets than in the later simulations: [zonal wind] [vorticity]

Liu, J., and T. Schneider, 2010: Mechanisms of jet formation on the giant planets. Journal of the Atmospheric Sciences67, 3652-3672. [PDF] [Official version]

Schneider, T., and J. Liu, 2009: Formation of jets and equatorial superrotation on Jupiter. Journal of the Atmospheric Sciences66, 579-601. [PDF] [Official version]