On the distribution of significant wave height and associated peak periods

This study uses 21 years (1958-1978) significant wave height and associated peak periods off Azores in the North Atlantic Ocean, extracted from 44 years HIPOCAS database. Empirical average conditional exceedances of peak periods are executed. Plausibility of judging the distribution of the peak periods by modelling average conditional exceedance of peak periods by Erlang, generalized Pareto and three-parameter Weibull models is investigated and we also assessed certain peak period statistics predicted by the models. 50 year gamma peak period quantiles are reasonably accurate when compared with 44 year peak period quantiles (HIPOCAS). Erlang and generalized Pareto estimate of mean peak period are reasonable; whereas all the three models fairly evaluate the average of the one-third the highest peak periods. Weibull model derived parametric relation gauged the average of the one-tenth the highest peak periods. A general statistical formula is suggested for estimation of significant wave period. Average of one-third the highest peak period estimates by the parametric relation derived from generalized Pareto distribution using the general formula for significant wave period, provides reliably precise results. Significant wave period to mean wave period observational ratio of 1.2 is appropriately interpreted for both computed and estimated ratios of mean peak period of one-third the highest significant wave heights to mean peak periods.