Estimation of a Freak Wave Lifetime in the Shallow Sea

Abstract

Unexpected large waves known as freak or rogue waves are a phenomenon emerging in the World Ocean and are causing significant damage to vessels and coastal structures. These waves are often associated with deep-water waves; however, they can also be dangerously close to the shore. The present study is devoted to the numerical modeling of the sea state with parameters close to the ones of the freak wave event that happened in Tillamook Bay, Oregon, on 25 January 2007. Parameters of waves and winds are taken from the description of the event and from the reanalysis model ERA5, which proved to be in good agreement. The Korteweg–de Vries equation is chosen to be the model for the numerical simulation as it is an etalon model for water waves in shallow water with weak nonlinearity and dispersion. Possible scenarios of occurrence of freak waves have been analyzed. Lifetimes of freak waves of different shapes have been estimated.