Numerical Simulation of Extreme Water Level of Multiyear Return Period in the Bohai Sea

摘要

In this paper, a numerical model of the coupling between astronomicaltide and storm surge based on a 3-D hydraulic model for estuary andcoast (ECOMSED) is confirmed to be suitable for simulation of stormsurge in the Bohai Bay. The maximum surges caused by typhoons from1989 to 2008 are simulated; the yearly extreme water levels on gridsand the spatial distribution of extreme water level of different returnperiods in the Bohai Bay are concluded. It shows that tidal range andsurge increase from deep water to shallow water as a whole. Extremewater level in deep water are smaller than shallow water, the spatialdistribution of extreme water level is influenced by topography. Fromthe simulation result, the maximum surges at Tanggu and its adjacentsea area are 1.88m, 1.65m and 1.57m in 1992, 1997 and 2003,respectively. The maximum extreme water level of 50-year returnperiod is about 4.35 m which mainly occurs in the adjacent area fromreclamation district of north Tianjin Harbor to Dashengtang. Thespatial pattern of extreme water level of 25-year return period and 100-year return period are similar to that of 50-year return period, theextreme water level also occur in the adjacent area of north TianjinHarbor, but the areas of extreme water level of different return periodsare different.