The decay of dipolar vortices due to wave radiation #

Matthew Crowe

10:30 Tuesday in 4Q07.

Part of the Geophysics and climate session.

Abstract #

Modons, or dipolar vortices, are a family of analytic solutions describing a co-propagating vortex pair. These solutions exist for a wide range of problems in geophysical fluid dynamics and have been used to model atmospheric and oceanic phenomena. When travelling through a fluid which supports waves, modons can generate a wave wake and gradually decay as their energy is transferred into the wave field and radiated away. In this talk, I will outline how an energy balance can be used to derive simplified equations describing the evolution of the vortex speed and radius. This theory is then applied to a range of different problems including shallow-water coastal flow, 2D stratified flow and quasi-geostrophic flow over a beta-plane and tested using numerical simulations.