Estimation of design wave height using empirical simulation technique

Abstract

In this study, we applied the empirical simulation technique (EST) to the estimation of deepwater design wave heights in several areas in the South Coast of Korea. For the historical typhoons that impacted each area during 59 years from 1951 to 2009, numerical simulations were performed to calculate the wave fields. The simulation results were then used for the generation of the training sets of the EST. The results of the EST were compared with those of the least squares method (LSM) used along with the peaks-over-threshold method. For the 50-year return period wave heights, the EST estimated larger values than the LSM by 2%–26%. If the difference between the EST and the LSM is small for the 50-year return period wave height, the LSM and the EST estimate similar wave heights throughout the return period. If the difference is large, the LSM gives larger wave heights than the EST for relatively short return periods, while the opposite happens for longer return periods. This difference between the EST and the LSM is attributed to the bounce of the relative frequency of wave height at the largest waves (or the occurrence of large wave heights off the increasing trend of wave height with return period).