Stability of a two-layer fluid model to nongeostrophic disturbances

William Blumen

doi:10.3402/tellusa.v25i1.9640

Stability of a two-layer fluid model to nongeostrophic disturbances

Tellus

Volume 25 (1973): Issue 1

By: William Blumen

Open Access

|Jan 1973

Abstract

Sufficient conditions for stability of a linear inviscid two-layer model to nongeostrophic disturbances are derived. A bound on the growth rate of an unstable disturbance is also found. When the Rossby number R_0≪1, these conditions reduce to the results established by Pedlosky (1964) within the confines of quasi-geostrophic theory. The present analysis provides a theoretical framework for further investigations of fluid systems characterized by strong concentrations of horizontal momentum, such that R₀ ≤ 0(1). Application to atmospheric jet streams and the Gulf Stream, for example, is suggested by observationally established characteristics of these flow regimes.

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