Wave-wave interaction of unstable baroclinic waves.

Abstract

Two slightly unstable baroclinic waves in the 2-layer Phillips model are allowed to interact with each other as well as the mean flow. A theory for small dissipation rates is developed to examine the role of wave-wave interaction in the dynamics of vacillation and aperiodicity in unstable systems. In particular, dissipation proportional to potential vorticity is shown to expunge amplitude vacillation due to wave-mean flow interaction. Wave-wave interaction, however, can yield amplitude vacillation. As the dissipation is decreased, the solutions evolve from steady waves (although propagating) to periodic vacillation until finally at small dissipation rates, chaotic behavior is obtained.-from Authors