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arXiv · 2004.08148

Wave Triad with Forcings as a Nambu System

Richard Blender·Joscha Fregin
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Abstract

The dynamics of an ideal wave triad with real amplitudes has a well-known Nambu representation with energy and enstrophy as conservation laws. Here we derive Nambu representations for systems with constant forcings. These equations have been applied to triads of Rossby-Haurwitz waves in the atmosphere where they are forced with orography. The conservation laws are based on relations for the unforced amplitudes and a Hamiltonian given by the total energy plus terms involving the unforced amplitudes. The forcing of the unstable wavenumber causes a recharge cycle.

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Richard Blender, Joscha Fregin. 2020-04-17. Wave Triad with Forcings as a Nambu System. https://arxiv.org/abs/2004.08148

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