Nonlinear Processes in Oceanic and Atmospheric Flows

Presentation

Zonal jet growth as a phase instability

Author: Louis Marié, Laboratoire de Physique des Océans, UMR 6523.

Names and affiliation of other authors:

Oral or poster: Oral presentation

Downloadable talk file:

Zonal jet growth as a phase instability

(Louis_Marie_NLOA2008.pdf, 757748 bytes)

Abstract:
We study the linear instability of plane Rossby waves to zonal perturbations (jets).
Using a phase dynamics formalism, we derive simple equations describing the interactions between the jets and waves.
We show that the growth of the jets can be easily understood as a phase instability of the waves, for which different mechanisms can be isolated depending on the various parameters.
The accuracy of the asymptotic results is satisfactorily checked against numerical simulations.

*Satellite images from NASA and ESA

Nonlinear Processes in Oceanic and Atmospheric Flows. July 2-4, 2008. Castro Urdiales, Cantabria, Spain.