An Internal Wave as a Frequency Filter for Surface Gravity Waves on Water

TL;DR

This paper models the interaction between internal and surface gravity waves on water, showing that internal waves can act as a frequency filter for surface gravity waves in an idealized one-dimensional setting.

Contribution

It introduces a simplified one-dimensional model demonstrating how internal waves can serve as a frequency filter for surface gravity waves, ignoring effects like surface tension and wind.

Findings

Flow acts as a frequency filter for gravitational waves

Approximate solutions for surface wave height were derived

Internal waves influence surface wave behavior

Abstract

We consider one-dimensional model of the interaction between surface and the internal gravity water waves. The internal wave is modeled by its basic form: a non-dispersive field with a horizontal current that is uniform over all depth, insignificantly affected by the surface waves, while ignoring surface tension and wind growth/decay effects. The depth is infinite. Approximation for the height of the surface wave on the flow by the "elementary quasi stationary" solutions was found. It was shown that the flow acts as a frequency filter for gravitational waves on water.