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arXiv · 0805.0390

What drives mesoscale atmospheric turbulence?

H. Xia·H. Punzmann·G. Falkovich·M. Shats
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Abstract

Measurements of atmospheric winds in the mesoscale range (10-500 km) reveal remarkably universal spectra with the $k^{-5/3}$ power law. Despite initial expectations of the inverse energy cascade, as in two-dimensional (2D) turbulence, measurements of the third velocity moment in atmosphere, suggested a direct energy cascade. Here we propose a possible solution to this controversy by accounting for the presence of a large-scale coherent flow, or a spectral condensate. We present new experimental laboratory data and show that the presence of a large-scale shear flow modifies the third-order velocity moment in spectrally condensed 2D turbulence, making it, in some conditions, similar to that observed in the atmosphere.

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H. Xia, H. Punzmann, G. Falkovich, M. Shats. 2008-05-04. What drives mesoscale atmospheric turbulence?. https://arxiv.org/abs/0805.0390

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