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arXiv · 1309.6197

Beta-plane turbulence: experiments with altimetry

Y. Zhang·Y. D. Afanasyev
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Abstract

Results from a new series of experiments on barotropic and baroclinic turbulent flows generated in a rotating tank with topographic beta-effect are presented. The velocity fields are measured by the Altimetric Imaging Velocimetry. The turbulent flows observed in the experiments develop zonal jets which are latent in a stationary forced-dissipative regime of the flow but become prominent in the decaying flow. The two-dimensional energy spectra of the flows exhibit the development of anisotropy towards zonal motions. The experiments demonstrate dual turbulent cascade with energy and enstrophy ranges. The frequency-wavenumber spectra reveal the presence of Rossby waves at low wavenumbers which are excited by the turbulent motions. The experimental results are compared with available theory of beta-plane turbulence.

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Y. Zhang, Y. D. Afanasyev. 2013-12-20. Beta-plane turbulence: experiments with altimetry. https://doi.org/10.1063/1.4864339

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