Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-27T12:42:52.299Z Has data issue: false hasContentIssue false

Wave propagation across the continental shelf

Published online by Cambridge University Press:  29 March 2006

John W. Miles
Affiliation:
Institute of Geophysics and Planetary Physics, University of California, La Jolla

Abstract

Wave propagation across the continental shelf is studied by analogy with transmission-line theory. Fourier transformation along the contours of constant depth, which are assumed parallel to a straight coastline, yields a Sturm-Liouville equation for a prescribed depth profile h(x). The modal spectrum of the profile, which comprises a finite, discrete spectrum of trapped modes and a continuous spectrum of radiated modes, is established. The Green's function for a point source on the coastline is constructed by Fourier superposition over this spectrum. Detailed results are calculated for a two-step model (level shelf separated from level abyss by vertical cliff) and for a gradually sloping shelf that merges smoothly into a level abyss. The radiation impedance of a harbour is calculated, and the effects of the continental shelf on the resonant response of the harbour to a tsunami are discussed.

Type
Research Article
Copyright
© 1972 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ince, E. L. 1944 Ordinary Differential Equations. Dover.
Jeffreys, H. & Jeffreys, B. S. 1950 Methods of Mathematical Physics. Cambridge University Press.
Lamb, H. 1932 Hydrodynamics. Cambridge University Press.
Miles, J. W. 1971 Resonant response of harbours: an equivalent-circuit analysis. J. Fluid Mech. 46, 241265.Google Scholar
Munk, W., Snodgrass, F. & Gilbert, F. 1964 Long waves on the continental shelf: an experiment to separate trapped and leaky modes. J. Fluid Mech. 20, 529554.Google Scholar
Watson, G. N. 1945 A Treatise on the Theory of Bessel Functions. Cambridge University Press.