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arXiv · 0705.0011

Statistics of an Unstable Barotropic Jet from a Cumulant Expansion

J. B. Marston·E. Conover·Tapio Schneider
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Abstract

Low-order equal-time statistics of a barotropic flow on a rotating sphere are investigated. The flow is driven by linear relaxation toward an unstable zonal jet. For relatively short relaxation times, the flow is dominated by critical-layer waves. For sufficiently long relaxation times, the flow is turbulent. Statistics obtained from a second-order cumulant expansion are compared to those accumulated in direct numerical simulations, revealing the strengths and limitations of the expansion for different relaxation times.

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BibTeXRIS

J. B. Marston, E. Conover, Tapio Schneider. 2007-04-30. Statistics of an Unstable Barotropic Jet from a Cumulant Expansion. https://doi.org/10.1175/2007jas2510.1

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