Study on the Extreme High Water Levels and Wave Heights of Different Return Periods in Laizhou Bay, China

Based on good simulation results during storm events in 2009, MIKE21 was used to study the extreme water level, current velocity and wave height in Laizhou Bay, China. 95 extreme weather processes during 1988–2012 were simulated. For each event, coupled hydrodynamic and wave modules of MIKE21 was chosen to calculate the maximum water level and current velocity. The Gumbel distribution method, commonly used for estimating return-period values of marine hydrodynamic variables, is adopted in this study. The extreme high water level of 50-year return period in Laizhou Bay can reach 2.6–3.8 m; and that of 100-year return period can be as high as 2.8–4.6 m. The 50-year and 100-year return-period values of current velocity can reach up to about 2.8 m/s and 3.2 m/s respectively, both around the Yellow River mouth. Wave height strongly depends on water depth, water level rise, wind speed and direction. The results provide parameter reference for structure design in the Laizhou Bay.