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Waves induced by sources near the ocean surface

Published online by Cambridge University Press:  21 April 2006

Y. P. Guo
Y. P. Guo
Affiliation:
Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK
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Abstract

The problem of wave generation by sources near the ocean surface is examined. The model is used to deduce that in the ocean, at low frequencies, both sound and surface gravity waves are possibly induced by the same sources. Sound radiation from particular sources is significantly influenced, at low frequencies, by surface waves which themselves are almost unmodified by fluid compressibility. The wave fields and energy levels are calculated analytically in a simple model of point-source excitation, which reveals considerable character. The theory is used to interpret measurements from the real ocean in the case where the source is a finite distribution of surface pressure fluctuations caused by winds. Good consistency is found in both structure and order of magnitude. Our main conclusions are that surface waves and wave-related sound are not necessarily cause and effect; a considerable proportion of the wave-associated underwater sound in the ocean is very likely generated by the same sources that produced the surface waves themselves.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 181 , August 1987 , pp. 293 - 310
Copyright
© 1987 Cambridge University Press

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