在风暴潮灾害中, 台风、天文高潮位、区间暴雨和上游洪水等因子存在同时出现的可能, 对沿海地区的防汛安全形成了较为严重的威胁. 双因子、多因子影响下的复合风暴潮灾害成为沿海地区灾害风险评估的主要研究对象. 风暴潮水通过漫堤和溃口进入陆域后, 河网对潮水的调蓄和运输作用直接影响对受灾区域灾害危险性的评估结果. 本研究选取上海市金山区作为典型区域, 基于MIKE11和MIKE21模型分别建立金山区一维河网模型和二维陆面模型, 并进行耦合计算, 模拟分析在风暴潮、台风、区间暴雨和流域洪水的综合影响下, 金山区地面积水变化过程, 为区域的灾害危险性分析提供依据. 模型计算结果表明, 在考虑陆域河网调蓄作用后, 风暴潮引起的金山区地面积水大幅度减小, 区域内整体淹没分布出现一定程度的改变. 综合考虑风暴潮及区间暴雨和流域洪水与仅考虑风暴潮条件相比, 金山区中部和北部大部分区域危险性等级降低, 西北角危险性等级升高.

Extreme precipitation and floods may occur during a storm surge hazard, accompanied by typhoon conditions and high tide levels. The combination of these factors intensifies the risk of flooding in coastal regions suffering from a storm surge. Thus, multi-impact analysis should be applied to determine flood risk during a storm surge. River networks play an important role in flood processes. The storage and transportation capacity provided by rivers can directly change the distribution of a flood. In this paper, a 1-D river network model and a 2-D surface model were respectively established and coupled to simulate the flood processes during an assumed storm surge in Jinshan District, Shanghai. The cumulative influence of the concurrent storm surge, typhoon, rainfall, and upstream flooding was explored to support hazard risk analysis for Jinshan District. The coupled model’s simulation indicated a clear decrease in the number of waterlogged areas in Jinshan District after considering the river network’s storage and transportation capacity during a storm surge event. The distribution of predicted waterlogged areas also changed; according to the simulation results, the flood risk grade decreased in the central and northern Jinshan District and rose in the Northwest corner.