Dynamics of a Quasigeostrophic Ellipsoidal Vortex Moment Model


Neil Burrell, Keith Julien, Jeff Weiss,

University of Colorado, Boulder



Stably stratified atmospheres and oceans are well-approximated by the 3D-quasigeostrophic equations. Numerical simulations show that the fluid is populated by nearly ellipsoidal, moderate aspect-ratio coherent vortices. The ellipsoidal moment model provides a Hamiltonian description of these vortices. For two vortices, after reduction, the moment model has an eight dimensional phase space. We investigate the dynamics of this system, focusing on the physically important processes of vortex merger and vertical alignment.