On the joint tropical cyclone wind and wave hazard

A simulation-based framework to estimate tropical cyclone (TC) induced wind and wave hazards is proposed by considering the TC tracks, wind field model, and significant wave height model. The proposed approach is applied to several offshore sites located near the coastline of mainland China, Both the block maximum analysis and event-based analysis are carried out. It was concluded that the marginal distribution of the annual maximum wind speed and of annual maximum significant wave height could be modelled using the generalized extreme value distribution. Plots of paired samples in terms of probability of the annual maximum wind speed (significant wave height) and of its companion significant wave height (wind speed) suggested that they could be characterized using Gumbel copula. The ranked correlation coefficient (i.e., Kendall's tau) varies from about 0.4 to 0.7, depending on the considered paired random variable and site. The implication of the results in assigning the load combination factor for combined TC wind and wave load effect is discussed. The deaggregation results indicate that the identified most likely event causing p-quantile of the annual maximum wind speed differs from that identified from p-quantile of the annual maximum significant wave height. Therefore, for the reliability analysis, risk modelling, and emergency preparedness, it is recommended that two sets of hazard characterizations are be considered: one based on the maximum of wind speed and its companion wave height, and the other based on maximum wave height and its companion wind speed.