中国东南沿海城市海啸灾害风险评估

Risk assessment of tsunami of the cities along the southeast coast of China

中国东南沿海地区是人口聚集、经济发达的区域,但附近海域存在有多个潜在海啸源,海啸灾害风险不容忽视。基于灾害系统理论,本文应用概率海啸危险性分析(PTHA)模拟沿海地区在不同重现期下的最大海啸波幅分布。同时构建了东南沿海地区承灾体暴露性和脆弱性评价指标体系,综合考虑海啸危险性以及承灾体暴露性和脆弱性的分析结果作为海啸灾害风险评估方案。结果表明,珠江三角洲地区沿海城市处于海啸高风险,如香港、澳门,重现期为2000年时,最大海啸波幅接近3 m,承灾体的暴露性属于最高水平,脆弱性水平较低。靠近台湾海峡的福建省区域部分城市处于较高风险水平,如泉州、厦门等,重现期为2000年时,最大海啸波幅超过2 m,承灾体的暴露性和脆弱性都属于较高水平。

Population agglomeration and economic development are the characteristics of southeast coastal areas of China,and there are several potential tsunami sources nearby,so the tsunami risk cannot be ignored. According to the systematic disaster theory,the probabilistic tsunami hazard analysis(PTHA)was used to simulate the tsunami in the coastal area to obtain the largest tsunami run-up distribution along the coast during the typical return period.The evaluation index system of exposure and vulnerability of disaster-bearing bodies in southeast coastal was constructed. The results of tsunami hazard and exposure and vulnerability of disaster-bearing bodies were comprehensive considered as the tsunami risk assessment scheme. The results show that coastal cities in the Pearl River Delta region,such as Hong Kong,are at high risk of tsunami. The tsunami run-up is close to 3 m in 2000 years,and the exposure of the disaster-bearing body was at the highest level and the vulnerability level was low. Other cities in Fujian Province near the Taiwan Strait are at a higher risk level,such as Quanzhou and Xiamen. The tsunami run-up is higher than 2 m in 2000 years,both the exposure and vulnerability are at a high level.