SESZIONE DI TORINO
After a brief overview on operational models commonly used for predicting significant wave heights and wave periods on the ocean, I will discuss some mechanisms of formation of extreme waves. Using the weak turbulence approach, I will show how strong deviations from Gaussian statistics of the surface elevation (extreme waves) can be naturally included in the description of water waves. Closed equations for third and fourth order moments of the surface elevation as a function of the spectral wave action density are derived. These results represent a first step towards the possibility of forecasting freak waves. Analytical results will be also compared with experimental data recently obtained in Marintek (Norway), one of the largest wave basins in the world. The possibility of deviations from Gaussian statistics in crossing sea states (wind sea and swell) will also be discussed in terms of coupled Nonlinear Schroedinger equations.

DATA: 15-02-2008