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Trapped internal waves over undular topography

Published online by Cambridge University Press:  26 April 2006

C. Kranenburg
Affiliation:
Department of Civil Engineering, Delft University of Technology, PO Box 5048, 2600 GA Delft, The Netherlands
J. D. Pietrzak
Affiliation:
Delft Hydraulics, PO Box 177, 2600 MH Delft, The Netherlands Present address: Department of Oceanography, University of British Columbia, Vancouver, BC. Canada V6T 1W5.
G. Abraham
Affiliation:
Delft Hydraulics, PO Box 177, 2600 MH Delft, The Netherlands

Abstract

We describe observations of slowly decelerating stratified flow over undular bottom topography in an estuary. The flow, which initially was supercritical with respect to the first internal wave mode, approached a resonance after it had become subcritical. A series of acoustic images showed large-amplitude first-mode trapped waves during this phase of the tide. We derive a criterion for quasi-steady response, and present an extension of Yih's class II linear finite-amplitude solutions that accounts for the waves observed.

Type
Research Article
Copyright
© 1991 Cambridge University Press

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