Nonlinear Propagation in a Depth-Dependent Ocean.

Abstract : The propagation of finite-amplitude sound in a depth-dependent ocean has been studied analytically and numerically, using a model based on weak-shock theory and the high frequency ray approximation. Results are presented for the equivalent propagation distance, in a uniform ocean, which reproduces the nonlinear distortion in the real situation. Numerical results for typical ocean properties are collapsed by means of an asymptotic theory, for ray paths along which the sound speed increases or decreases monotonically. Results are also shown for rays which form caustics.