Bulletin of the American Physical Society
71st Annual Meeting of the APS Division of Fluid Dynamics
Volume 63, Number 13
Sunday–Tuesday, November 18–20, 2018; Atlanta, Georgia
Session KP1: Poster Session (3:20-4:05pm)
Monday, November 19, 2018
Georgia World Congress Center Room: Level 1, Exhibit Hall B2 by the GFM videos
Abstract ID: BAPS.2018.DFD.KP1.106
Abstract: KP1.00106 : Decay of a mesoscale oceanic eddy: analysis of linear stability dynamics and critical levels
This study addresses the linear stability of an oceanic mesoscale eddy. A linear stability analysis of the quasi-geostrophic potential vorticity equation governing an idealized Gaussian vortex in a continuous stratification is performed, and the properties of the instability are analyzed. We show how growth of the instability is via mutual amplification of waves at different levels in the eddy, analogous to the Eady baroclinic instability. The fastest growing mode gives rise to enhanced vertical and horizontal density gradients that coincide with the critical level in the vicinity of the perturbed eddy; at this level, the mean angular speed is equal to the angular phase speed of the perturbation. We show how these enhanced density gradients relate to maximal radial water parcel displacement at the critical level. Results shed light on the physics of mesoscale eddy decay and further demonstrate the role of enhanced mixing at critical levels in the ocean.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2018.DFD.KP1.106
The American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics.
1 Physics Ellipse, College Park, MD 20740-3844
Editorial Office 1 Research Road, Ridge, NY 11961-2701 (631) 591-4000
Office of Public Affairs 529 14th St NW, Suite 1050, Washington, D.C. 20045-2001 (202) 662-8700