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An experimental study of homogeneous lenses in a stratified rotating fluid

Published online by Cambridge University Press:  21 April 2006

Katherine Hedstrom  and
Laurence Armi
Katherine Hedstrom
Affiliation:
Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093, USA Present address: Institute for Naval Oceanography, NSTL, MS 39529, USA.
Laurence Armi
Affiliation:
Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093, USA
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Abstract

Injection of a homogeneous fluid into a linearly stratified and rotating background fluid produced anticyclonic lenses which were studied for up to 600 rotation periods. Velocity measurements showed that the interior core rotates as a solid body with a decreasing, nearly axisymmetric exterior velocity field. Gill's (1981) model predicts well both the velocity and aspect ratio vs. Rossby number of the lenses. Lens decay occurred in two stages: symmetric rapid spin-down, with an associated half-life of ≈ 70 rotation periods followed by asymmetric shedding at a nearly constant core Rossby number, Ro ≈ 0.06.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 191 , June 1988 , pp. 535 - 556
Copyright
© 1988 Cambridge University Press

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