Laser-like wave amplification in straits

We present research on the excitation of ocean surface wind waves in non-homogeneous situations, for case a deep water strait presence constant wind, blowing perpendicular to coast line. The statistical wave model used is based Hasselmann equation with high-wavenumbers wave-breaking dissipation, exact non-linear four-wave interaction, and ZRP (Zakharov-Resio-Pushkarev (Zakharov et al. Nonlin Process Geophys 24:581–597 2017) input term. At first stage, propagate direction step-like moving front manner, which combination self-similar fetch-limited duration-limited solutions equation. second stage begins after intermediate linear asymptotics energy built along fetch. Beginning that time, groups, propagating across against due nonlinear are observed. Despite absence long-wave system asymptotically evolves into complex quasi-stationary state, comprised “wind sea” direction, quasi-monochromatic waves, radiating close orthogonally respect while slightly tilting from perfectly orthogonal angle slant increasing toward turbulence origination shore line, reaching 15∘ it. total asymptotic state exceeds sea by factor two quasi-orthogonal counter fields. Very similar structure was previously observed experimentally; this paper presents theoretical explanation these results.