2024/02/02 by Alexey Slunyaev, Slunyaev, A. V., Yury Stepanyants +1
Earth and Planetary Sciences · Engineering · #Arctic and Antarctic ice dynamics #FOS: Physical sciences #Geophysics (physics.geo-ph) #Pattern Formation and Solitons (nlin.PS) #Underwater Acoustics Research #Wave and Wind Energy Systems
paper · pdf · doi:10.48550/arxiv.2402.01164
openalex publication_date 2024/02/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study analytically and numerically a frequency downshifting due to power-type frequency-dependent decay of surface waves in the ocean covered by ice floes. The downshifting is obtained both within the linear model and within the nonlinear Schrödinger (NLS) equation augmented by viscous terms for the initial condition in the form of an NLS envelope soliton. It is shown that the frequency-dependent dissipation produces a more substantial downshifting when the spectrum is relatively wide. As a result, the nonlinear adiabatic scenario of wavetrain evolution provides a downshifting remarkably smaller in magnitude than in the linear regime. Meanwhile, interactions between nonlinear wavegroups lead to spectral broadening and thus, result in fast substantial frequency downshifts. Analytic estimates are obtained for an arbitrary power n of the dependence of a dissipation rate on frequency ∼ ωn. The developed theory is validated by the numerical modelling of the generalized NLS equation with dissipative terms. Estimates of frequency downshift are given for oceanic waves of realistic parameters.