Study of the generation of non-stationary non-linear long waves by atmospheric pressure disturbances

Abstract

In a non-linear statement, this paper considers the generation of long waves by periodic atmospheric pressure disturbances in a confined basin of variable depth filled with homogeneous fluids. The study is conducted using a non-stationary finite-difference model. The contribution of dissipative forces to the development and stabilization of fluid oscillations is analysed. The paper also considers how the growth of the amplitude of atmospheric pressure disturbances may enhance the non-linearity of the wave process. It is shown that as the pressure amplitude becomes larger, the number of significant harmonics with multiple frequencies in the spectrum of sea level elevations increases. For the weakly non-linear case, wave velocities and free surface elevations, with oscillations stabilized, are compared with their counterparts derived through the perturbation technique.