Ecoulements géophysiques


How does planetary rotation affects geophysical vortices ?

J. Park - Paul Billant

Geophysical vortices

Geophysical vortices are one the most famous subjects in geophysical fluid dynamics since, for example, they affect mixing properties in the oceans.

Numerical simulation of the Medditerranean eddy, from Ménesguen et al. 2009

Relative instability

Geophysical vortices are unstable due to an inertia-gravity wave emission, know as the radiative instability

Radiative instability on the flow around a rotating cylinder, from Riedinger et al. 2011

Objectives

Investigate an effect of planetary rotation on the radiative instability of a columnar vortex in stratified fluids.

Methods

Numerical and asymptotic linear stability analyses.

Results

The radiative instability is stabilized in the presence of both cyclonic and strong anticyclonic planetary rotations.

References

J. Fluid Mech., X.Riedienger, S. Le Dizès and P. Meunier (2010).
Geophys. Res. Lett., C. Ménesguen et al. (2009)
J. Fluid Mech., J. Park and P. Billant (2012)