An Empirical Model for Estimating the Geographic Location of Nonlinear Internal Solitary Waves

Abstract

This paper describes the development and performance of a new approach for estimating the geographic location of high-frequency nonlinear internal waves. The approach makes use of the internal wave signatures recorded in satellite imagery to determine the parameters of a model function that relates the internal wave phase speed to depth. The phase speed map produced by the parameterized model function establishes a propagation time and propagation path between an origin and any location in the region of interest. Contours of propagation time represent the internal wave locations for a particular time since generation. The parameters of the model function are found by minimizing the difference between the calculated propagation times and the observed propagation times. This approach is applied to the internal solitary waves observed in the northern portion of the South China Sea west of the Luzon Strait. Propagation time estimates based on this new approach have errors of ±1.32 h (1σ) for depths greater than 1000 m and ±2.55 h (1σ) for all depths over which the waves are observed.