Frequency Spectra and Surface Wave Height Distributions Based on the Measurements of Sakhalin Island

Spectral characteristics of long-term measurements of surface sea waves off the coast of Sakhalin Island by bottom pressure stations are analyzed. The shapes of frequency spectra in the wind wave range demonstrate great diversity and variability. The frequency of sea state conditions are determined in terms of the parameters of the frequency spectrum width and wave nonlinearity taking into account the change in the dimensionless parameter of depth at the measurement point. A significant decrease in the probability of high waves with increasing spectrum width, as well as with an increase in the ratio of the characteristic wave amplitude to depth or with an increase in the Ursell parameter is shown. The result is most clearly manifested when estimating the spectrum width through the Goda parameter.