The viscous nonlinear symmetric baroclinic instability of a zonal shear flow
- 15 April 1975
- journal article
- research article
- Published by Cambridge University Press (CUP) in Journal of Fluid Mechanics
- Vol. 68 (4) , 757-768
- https://doi.org/10.1017/s0022112075001218
Abstract
The stability of a baroclinic zonal current to symmetric perturbations on a meridionally unboundedf-plane is considered. The lower boundary is at rest but the upper one moves with a constant velocity in keeping with the velocity of the zonal current. Following Stone (1966) a horizontal length scaleO(Ro) is taken, whereRois the Rossby number, with the Richardson numberRi=O(1). Instability sets in when the wavelength isO(E1/3), whereEis the Ekman number based on the distance between the rigid horizontal boundaries, which corresponds to Stone's inviscid value zero, and to McIntyre's (1970) value infinity on a length scaleO(E½).A nonlinear analysis about the point of onset of instability yields the result that for the monotonic mode zonal momentum is convected polewards. The possible implications of this result for the dynamics of Jupiter's atmosphere are discussed.Keywords
This publication has 1 reference indexed in Scilit:
- Nonlinear Stability TheoryAnnual Review of Fluid Mechanics, 1971