EXTREME WAVE PREDICTION IN MARKOV CHAIN CONDITION

This paper discusses the effect of statistical dependence of the daily maximum significant wave heights assuming they are subjected to Markov chain condition. The formula of extreme wave prediction using daily maximum significant wave heights subjected to Markov chain condition is derived as a function of joint probability distribution of successive daily maxima , marginal distribution of daily maxima , correlation coefficient between successive daily maxima and sample size for which the extreme value distribution is studied.The extreme wave height is predicted for two cases: wave data fitted to Weibull distribution and fitted to log-normal distribution. Importance sampling procedure (ISP) is used for simulation of multivariate joint probability distribution. Analytical method is also used for bivariate log-normal distribution.Based on the observed wave data in Northern North Sea from 1975 to 1984 the 100 yrs. and 10 yrs. wave heights are predicted by proposed method with Markov concept and traditional method. Predicted results show that the 100 yrs. wave height with the Markov concept is about 10% less than those predicted by traditional method.