Equatorial Superrotation and Barotropic Instability: Static Stability Variants

Equatorial Superrotation and Barotropic Instability: Static Stability Variants

Altering the tropospheric static stability changes the nature of the equatorial superrotation associated with unstable, low-latitude, westerly jets, according to calculations with a dry, global, multilevel, spectral, primitive equation model subject to a simple Newtonian heating function. For a low static stability, the superrotation fluxes with the simplest structure occur when the stratospher...

Barotropic Instability and Equatorial Superrotation

Baroclinically unstable zones in midlatitudes normally produce medium-scale planetary waves that propagate toward the equator where they generate easterlies while transferring westerly momentum poleward, so that the jet lies in higher latitudes than in the corresponding axisymmetric (eddy-free) state. When the baroclinically unstable zone is moved into low latitudes, however, the equatorward si...

Equatorial superrotation in shallow atmospheres

[1] Simple, shallow-water models have been successful in reproducing two key observables in the atmospheres of the giant planets: the formation of robust, and fully turbulent, latitudinal jets and the decrease of the zonal wind amplitude with latitude. However, they have to date consistently failed in reproducing the strong prograde (superrotating) equatorial winds that are often observed on su...

The Matsuno‐Gill model and equatorial superrotation

[1] Equatorial superrotation can be generated in global general circulation models (GCMs) when forced with longitudinally varying heating, similar to that postulated in the Matsuno‐Gill model. However, the implications of the classical Matsuno‐Gill theory for equatorial superrotation have not, to date, been addressed. Here, we show that the classic, shallow‐water Matsuno‐Gill solutions do not e...

Equatorial Superrotation on Tidally Locked Exoplanets