Articles | Volume 12, issue 6
Nonlin. Processes Geophys., 12, 947–953, 2005
https://doi.org/10.5194/npg-12-947-2005

Special issue: Turbulent transport in geosciences

Nonlin. Processes Geophys., 12, 947–953, 2005
https://doi.org/10.5194/npg-12-947-2005

  04 Nov 2005

04 Nov 2005

Rossby-wave turbulence in a rapidly rotating sphere

N. Schaeffer and P. Cardin N. Schaeffer and P. Cardin
  • LGIT, Observatoire de Grenoble, Universit\'e Joseph Fourier, Grenoble, France

Abstract. We use a quasi-geostrophic numerical model to study the turbulence of rotating flows in a sphere, with realistic Ekman friction and bulk viscous dissipation. The forcing is caused by the destabilization of an axisymmetric Stewartson shear layer, generated by differential rotation, resulting in a forcing at rather large scales.
The equilibrium regime is strongly anisotropic and inhomogeneous but exhibits a steep m-5 spectrum in the azimuthal (periodic) direction, at scales smaller than the injection scale. This spectrum has been proposed by Rhines for a Rossby wave turbulence. For some parameter range, we observe a turbulent flow dominated by a large scale vortex located in the shear layer, reminding us of the Great Red Spot of Jupiter.