Coupling of Acoustic Modes in the Ocean, A Comparison of Approximate Solutions

  • Yves Desaubies
Part of the NATO Conference Series book series (NATOCS, volume 16)

Abstract

The representation of the acoustic field in a waveguide in terms of an infinite sum of normal modes is exact. However, when the properties of the waveguide are range-dependent, the modes (and their associated eigenvalues) can only be defined locally. The range variation of the amplitudes of the modes is a coupled set of ordinary second order differential equations. Under some conditions the coupling can be neglected and one obtains the adiabatic approximation to the solution1, 2. We have discussed elsewhere3, 4 the conditions of validity of the adiabatic solution by carrying out a formal asymptotic series solution. It was found that for typical mesoscale eddies in the ocean coupling could be significant. Further modelling presented here confirms those findings.

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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • Yves Desaubies
    • 1
  1. 1.Institut Francais de Recherche pour l’Exploitation de la MerBrest CedexFrance

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