Vortex interaction with a zonal Rossby wave in a quasi-geostrophic model

Computer Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1

Scientific paper

An analytical theory is presented for the motion of a localized vortex in the presence of a zonal Rossby wave on the β-plane. In the framework of the equivalent-barotropic quasi-geostrophic model, the analytical method developed by Sutyrin and Flierl [Sutyrin G.G., Flierl G.R., 1994. Intense vortex motion on the β-plane: development of the beta gyres. J. Atmos. Sci. 51, 773 790] for intense vortices with piecewise-constant potential vorticity is generalized to take into account a slowly propagating Rossby wave which modifies the background potential vorticity. The predictions of these asymptotic expansions are compared with the results of numerical simulations. The theory describes the vortex advection by the wave and the vortex drift due to the background potential vorticity gradient. The net vortex drift speed due to the wave is found to be smaller than the maximum wave velocity; this is due to the baroclinic β-effect and to the periodic structure of the background potential vorticity gradient. Besides known elliptical core deformations, triangular deformations are generated by the wave on the core boundary. Additionally, the planetary β-effect provides a predominantly westward vortex drift with nearly the same speed as the wave propagation speed. The asymptotic theory is shown to agree well the results of a numerical pseudo-spectral, high-resolution biperiodic model when the vortex velocity is much larger than the wave velocity. Both meridional and zonal vortex drifts are slightly overestimated when the wave velocity is comparable with the vortex velocity. Vortex size is shown to be more influential on vortex trajectory than the Rossby wave length. In particular, smaller vortices drift westward farther and faster than large ones. Vortex core deformations typically contain modes 2 and 3 with a stronger mode 3 component for more intense Rossby waves as predicted by theory.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Vortex interaction with a zonal Rossby wave in a quasi-geostrophic model 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 Vortex interaction with a zonal Rossby wave in a quasi-geostrophic model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vortex interaction with a zonal Rossby wave in a quasi-geostrophic model will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1059136

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.