Long-term analysis of waves off Mangaluru coast

Abstract

A competent coastal engineer should have adequate knowledge with regard to wave analysis. Long-term analysis is being effectively used worldwide to predict wave heights based on extreme wave statistics. The objective here is to analyze the ocean waves off Mangaluru coast, India. Long-term analysis is initially performed based on probability distributions like Log-normal distribution, Gumbel distribution, Fretchet distribution, Exponential distribution, and Weibull distributions on the in-situ wave data recorded at coastal waters off Mangaluru coast. The Extreme wave analysis is performed based on Peak Over Threshold method from which the best-fit probability distribution is obtained. Further, the best performing distribution is applied on the simulated wave heights obtained from MIKE 21 numerical model forced with ERA-interim wind speed data of 38-years. From the analysis, amongst the five different distributions considered Weibull distribution with α = 1.3 gave the best-fit for the wave dataset considered. Long-term analysis is then performed on 38-years hindcast data for 10, 50 and 100 year return periods for the Mangaluru coast region.