Statistics of an Unstable Barotropic Jet from a Cumulant Expansion
نویسندگان
چکیده
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.
منابع مشابه
Direct statistical simulation of out-of-equilibrium jets.
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