Modeling the climatic variability of directional wave spectra

The problem of sea wave climate description through climatic directional spectra is addressed and an example application is made to Portuguese coastal waters and Northeast Atlantic locations. The 44-year HIPOCAS hindcast data set is used for spectral parameterization, and statistical calculations are made for five locations: Figueira da Foz, Sines, Azores, Madeira (Caniçal) and Canaries. The occurrences of the spectral classes are estimated, and for each class the variability of the spectral parameters is described in terms of joint distributions. Different approaches for its parametric estimation are considered. These statistics are used for calculation of synthetic directional wave spectra (including extreme sea states) for different wave-making conditions.