A Numerical Model for the Storm Surge in Bohai Bay of China

Recent year storm surges frequently land on Bohai Bay of China. In autumn and spring, the storm surge caused by front winds happened frequently. It is given more attention at the forecast system as the serious impact on the development of docks, oil platforms, economic development zone, and recreational beach in the area. Therefore, this study focuses on achieving a fast, continuous and high-resolution predicting model for temperate storm surge for Bohai Bay. Harmonic analysis was applied to provide open boundary conditions; and local deepening, water range reducing were to deal with the boundary of shallow water. A fine MM5 (Meso-scale meteorological model) was adopted to offer more accurate wind field; ADI (Alternating Direction Implicit) difference scheme for solving equations kept the computation more stable. The model could achieve the non-linear effect between storm surge and astronomical tide totally. Based on the upper conditions, three storm processes were simulated separately in 5min by the above-mentioned numerical model. Comparisons and error analysis were conducted between the computed values and observed data in surge level and water elevation processes. Final results show that average relative error is 0.024 at the peak of sea level and 0.074 at the highest elevation in three simulated processes, computed results are agreed well with observed values in three sea level and water elevation processes. We believe the model with great applicable value can accurately forecast sea levels and elevations due to storm surge in this region.