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An instability of internal gravity waves

Published online by Cambridge University Press:  29 March 2006

Ronald Smith
Affiliation:
Fluid Mechanics Research Institute, University of Essex

Abstract

When water is slightly stratified, internal gravity waves are considerably shorter than surface waves of comparable frequency. Here, this fact is exploited in demonstrating that an internal wave is unstable when it forms part of a resonant triad with a surface wave and another internal wave whose wave number is approximately equal to that of the original internal wave. It is suggested that in a system where there are two classes of waves of comparable frequencies but greatly differing wavelengths the short waves may be expected to generate long waves by this mechanism.

Type
Research Article
Copyright
© 1972 Cambridge University Press

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References

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