EFFECT OF THRESHOLD VALUES ON THE PREDICTED EXTREME WAVES-A CASE STUDY IN UAE TERRITORIAL WATERS

The effect of varying the threshold value on the predicted extreme significant wave height is investigated. 25 different locations in the UAE territorial water is used for this case study. Threshold value is varied from 0.75 m to 4.5 m with increment of 0.25 m. Gumbel and Weibull extreme value distributions are used for the extreme wave analysis and Weibull distribution is found to be better for all the locations. The value of shape parameter of the Weibull distribution is varied from 0.8 to 1.3 with increment of 0.05 and the best shape parameter is selected (based on the highest coefficient of regression value) and the corresponding location and scale parameter are used for predicting the extreme significant waves of different return periods. It is found that there is no definite trend in the predicted extreme significant wave height, when the threshold value is varied from 0.75 m to 4.5 m, for different selected locations. For some locations, the predicte