An investigation on the performance of the Hilbert-Huang Transform on the analysis of ocean waves time series

This work discusses the performance of the Hilbert-Huang method applied to the time-frequency analysis of ocean wave data. Brief conceptual and practical reviews are presented for both Fourier and Hilbert-Huang approaches to the analysis of ocean wave data. Then, both methods are applied to the analysis of real wave time series. The time series subject to analyses were obtained by a directional wave meter installed on the southern Brazil continental shelf (32 10′S, 51 58′W). The water depth at the location is 15 meters and the data were obtained during three years. The Hilbert-Huang results for spectra are compared with those of the Fourier analysis. The application of the time-frequency method leads to significant improvements regarding the representation of both nonlinear and non-stationary ocean wave processes.