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| Baey, Jean-michel; Carton, Xavier. |
| The stability of elliptically perturbed circular vortices is investigated in a two-layer shallow-water model, with constant background rotation. The fluid is bounded above and below by rigid and flat surfaces. The linear stability analysis shows that elliptical perturbations are most unstable for moderate Burger numbers and vorticity shears. Shorter waves dominate for more sheared vortices. Shallow-water and quasigeostrophic growth rates exhibit a striking similarity, except at each end of the Burger number domain. There, cyclones (anticyclones) with finite Rossby numbers are more (less) unstable than their quasi-geostrophic counterparts. A simple model gives a first-order trend for this bias. Nonlinear model runs with initially perturbed vortices also... |
| Tipo: Text |
Palavras-chave: Stability analysis; Vortex; Shallow water. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/publication-645.pdf |
