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- Sergey Danilov
- Alfred Wegener Institute for Polar and Marine Research, 27515 Bremerhaven, Germany
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- David Gurarie
- Case Western Reserve University, Cleveland, Ohio 44106
書誌事項
- 公開日
- 2004-07-01
- DOI
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- 10.1063/1.1752928
- 公開者
- AIP Publishing
この論文をさがす
説明
<jats:p>A beta-plane approximation of the two-dimensional quasigeostrophic model describes a single layer (barotropic) fluid subjected to a latitudinally varying Coriolis parameter or topography. Rhines (1975) initiated the study of beta-plane turbulence. He predicted the inverse energy cascade into predominantly zonal modes, hence an array of eastward–westward jets, and estimated the jet number (celebrated Rhines scale). He also proposed a k−5 scaling law of zonal energy spectra. Our paper re-examines scaling, spectra, and zonal structure of beta-plane turbulence, based on theoretical predictions and numeric experiments. We show that the inverse cascade gives rise to strong organized zonal jets that evolve a peculiar frontal-band (“saw-tooth”) vorticity profile. Such structure affects all spectral properties of the system, by creating organized sequences of spectral peaks, and thus confounds any putative “scaling behavior.” The frontal-band structure appears consistently in all stochastically forced beta-plane flows, independent of dissipation and/or other details. But the resulting turbulent quasiequilibrium is not unique, its gross parameters (jets number, mean vorticity gradient) retain memory of the initial state and/or history.</jats:p>
収録刊行物
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- Physics of Fluids
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Physics of Fluids 16 (7), 2592-2603, 2004-07-01
AIP Publishing
