Bifurcations of the modal structure of internal waves in a fluid induced by a spatially periodical variation of the hydrostatic stability parameter

Abstract

The dispersion law of internal gravity waves in a stratified fluid at rest is investigated: it is shown that the introduction of an oscillating component of the stratification parameter along the vertical direction introduces an infinite number of branches of the dispersion relation. The importance of this effect for the estimate of the triadic nonlinear interaction between internal waves is suggested as one of the most relevant consequences of the results reported.