Universality of Sea Wave Growth and Its Physical Roots

TL;DR

This paper proposes a universal law linking wave steepness to development time or fetch, emphasizing nonlinear interactions over wind forcing, supported by simulations and experiments, challenging traditional wave modeling approaches.

Contribution

It introduces a simple, wind-independent relationship for wave growth based on nonlinear interactions, supported by numerical, in situ, and tank data.

Findings

Wave steepness correlates with development time and fetch.

The proposed law is validated by multiple experimental methods.

It challenges conventional wind-driven wave growth models.

Abstract

Modern day studies of wind-driven sea waves are usually focused on wind forcing rather than on the effect of resonant nonlinear wave interactions. The authors assume that these effects are dominating and propose a simple relationship between instant wave steepness and time or fetch of wave development expressed in wave periods or lengths. This law does not contain wind speed explicitly and relies upon this asymptotic theory. The validity of this law is illustrated by results of numerical simulations, in situ measurements of growing wind seas and wind wave tank experiments. The impact of the new vision of sea wave physics is discussed in the context of conventional approaches to wave modeling and forecasting.