Astronomy and Astrophysics – Astronomy
Scientific paper
Jul 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997dps....29.2406d&link_type=abstract
American Astronomical Society, DPS meeting #29, #24.06; Bulletin of the American Astronomical Society, Vol. 29, p.1017
Astronomy and Astrophysics
Astronomy
Scientific paper
We study the simplest possible coupled atmosphere-interior model for a gas-giant planet. The model is quasigeostrophic and consists of two active layers. Layer 1 models the thin spherical-shell extratropical atmosphere and is characterized by planetary-vorticity gradient beta_1 = df/dy. Nondimensionalizing by the horizontal wind speed, U, and the horizontal length scale, L, the value for Jupiter is beta_1 ~ 1/3, which expresses the violation of the sufficient barotropic shear-stability criterion (|beta_1 | >= 1) found on Jupiter. To capture the deep spherical geometry and Taylor-Proudman effect, we follow Ingersoll and Pollard and examine beta_2 ~ -1 != beta_1 . We study the linear stability problem, calculate growth rates for unstable initial configurations, identify stable and marginally stable configurations, and run fully nonlinear simulations of unstable configurations. Two key parameters are the ratio of upper-layer to lower-layer depth, delta , which is typically kept small, and the inverse square of the upper-layer deformation radius, or Froude number, F_1. When initialized with random turbulence, the model spontaneously forms alternating jets in the deep layer that evolve to become barotropically stable (beta_2 <= -1), basically following the Rhines scaling, and forms similar alternating jets in the upper layer that violate the barotropic stability condition but are nevertheless stable with respect to Arnol'd's 2nd stability criterion. Isolated eddies tend to persist in the simulations after the jets have emerged, which is characteristic of the gas-giant planets. These results are consistent with the Voyager data analysis and modeling of Dowling (1993, J. Atmos. Sci. 50: 14--22), and motivate full-scale atmosphere-interior modeling efforts.
Dowling Timothy E.
Flierl Glenn R.
No associations
LandOfFree
Alternating Jets in a Coupled Two-Layer Atmosphere-Interior Model of the Extratropical Latitudes of a Gas-Giant Planet does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Alternating Jets in a Coupled Two-Layer Atmosphere-Interior Model of the Extratropical Latitudes of a Gas-Giant Planet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Alternating Jets in a Coupled Two-Layer Atmosphere-Interior Model of the Extratropical Latitudes of a Gas-Giant Planet will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1188720