Joint distributions for significant wave height and wave zero-up-crossing period
Several types of joint distribution function for significant wave height and zero-upcrossing period are compared with reference to measured wave data from the Norwegian Continental Shelf. The comparison is based on the utility of the distribution functions for predictions of extreme response of offshore structures. Logarithmic contour plots and contour plots of normalised deviations between the data and the fitted distribution are used in the comparison. A joint distribution combining a marginal 3-parameter Weibull distribution for significant wave height with a conditional log-normal distribution for zero-up-crossing period is recommended on the basis of this investigation.
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