Phase and Travel-Time Variability of Adiabatic Acoustic Normal Modes due to Scattering from a Rough Sea Surface, with Applications to Propagation in Shallow-Water and High-Latitude Regions

摘要

Simple theoretical expressions are generated for the phase and travel-time variations (specifically wander and bias) of normal modes due to scattering by a rough ocean surface. These expressions are explicitly demonstrated for two canonical waveguide examples, the hard-bottom (shallow water) waveguide and the n2-linear (high latitude) waveguide. Numerical examples of the scattering statistics generated for both waveguides are given, and the implications of the examples for shallow-water acoustics, high-latitude acoustics, and ocean acoustic tomography are discussed. An application of the theory developed to the cross coherence of modes measured in an Arctic waveguide during FRAM IV is also shown. Keywords: Rough surface scattering, Adiabatic mode theory, Travel time perturbation, Reprints. (JHD)