Wave-averaged balance: a simple example

Kafiabad, Hossein A.; Vanneste, Jacques; Young, William R.

Abstract

In the presence of inertia-gravity waves, the geostrophic and hydrostatic balance that characterises the slow dynamics of rapidly rotating, strongly stratified flows holds in a time-averaged sense and applies to the Lagrangian-mean velocity and buoyancy. We give an elementary derivation of this wave-averaged balance and illustrate its accuracy in numerical solutions of the three-dimensional Boussinesq equations, using a simple configuration in which vertically planar near-inertial waves interact with a barotropic anticylonic vortex. We further use the conservation of the wave-averaged potential vorticity to predict the change in the barotropic vortex induced by the waves.

Citation

Kafiabad, H. A., Vanneste, J., & Young, W. R. (2021). Wave-averaged balance: a simple example. Journal of Fluid Mechanics, 911, Article R1. https://doi.org/10.1017/jfm.2020.1032

• Journal Article Type: Article
• Acceptance Date: Nov 11, 2020
• Online Publication Date: Jan 25, 2021
• Publication Date: Mar 25, 2021
• Deposit Date: Oct 31, 2024
• Journal: Journal of Fluid Mechanics
• Print ISSN: 0022-1120
• Electronic ISSN: 1469-7645
• Publisher: Cambridge University Press
• Peer Reviewed: Peer Reviewed
• Volume: 911
• Article Number: R1
• DOI: https://doi.org/10.1017/jfm.2020.1032
• Public URL: https://durham-repository.worktribe.com/output/2994123