浙江沿海超强台风风暴潮灾害的影响及其对策

Study on the calamity and counter-measure of the super typhoon storm surge along the Zhejiang coastal area

对浙江省历史台风基本资料进行分析后发现,近年来台风严重影响浙江的趋势和登陆浙江的台风个数均有明显的增强和增加。浙江省沿海各测站的历史最高潮位均由台风暴潮引起,其中"9417"号、"9711"号两次台风与天文大潮遭遇引起的风暴潮次数占了绝大多数。受台风暴潮影响时,岸边观测到的潮位由天文潮和台风引起的增水两部分组成。采用潮波与风暴增水耦合的非线性效应模型研究了风暴潮。在验证"5612"号、"9417"号、"9711"号、"0414"号、"0509"号和"桑美"6场台风暴潮的基础上,模型以1949年以来我国大陆沿海最强的一次台风("5612"号台风)参数为基础,设计了台风在浙北(穿山)、浙中北(石浦)、浙中(椒江)、浙中南(坎门)和浙南(琵琶门)登陆的5条路径,以反映超强台风在浙江沿海不同地点登陆与天文高潮位"碰头"时可能造成的最高潮位,它可以基本代表超强台风登陆浙江沿海时的风暴潮位。根据两潮耦合模型计算得到的沿海高潮位与海塘塘顶高程进行比较,分析沿海海塘发生漫顶甚至溃堤的可能性。通过对海塘可能损毁机理的分析,根据不同登陆线路的超强台风在遭遇天文大潮高潮位时对浙江沿海可能造成的威胁程度进行淹没风险分析。在上述计算分析的基础上,结合浙江沿海的实际情况,提出相应的防御超强台风风暴潮的工程和非工程措施。

Due to the global warming and variation of atmospheric circulation, the number of typhoon landing or affecting the Zhejiang coast has increased in recent years. The intensity, air pressure, wind velocity and local storm rainfall of the typhoon continually shatter the historic records. The typhoon 9711 g and 9417 came up against astronomical spring tide, which resulted in significant disaster to Zhejiang coastal area in 1990s. After entering 21st century, four strong typhoons of 0414 # , 0509 # , 0515 # and 0608 # attacked the area, which brought about fateful disaster and fearful losses. The analysis of the historic data of typhoon in Zhejiang coastal area shows that the number of typhoon landing or affecting Zhejiang has a trend to increase. The historic maximum tidal levels at all the tidal stations of the province were caused by storm surge and most of them by the storm surge of typhoon 9711 # and 9417 #. During storm surge the tidal levels observed at coastal area consists of astronomic tide and water piling up by the typhoon. A nonlinear numeric model coupling tide and surge was used to study the phenomena. Base on the calibration of six storm surges of typhoon 5612 # , 9417 # , 9711# , 0414 # , 0509 # and 0608 # , the parameters of typhoon 5612 # , the strongest one that attacked our country since 1949, were taken as the base and five typhoon paths, that is, the north （Chuanshan）, the mid north （Shipu）, the mid （Jiaojiang）, the mid south （Kanmen） and the south （Pipamen） of Zhejiang were selected to calculate the potential high water level when typhoon landed at different site in Zhejiang coastal area.Possibilities of overtopping or even levee break are analyzed by comparison of the high water levels calculated with the model and the elevation of the sea wall. And the inundation risk level is also studied for super typhoon landing at different sites of the Zhejiang coastal area during astronomical spring tide through seawall destruction mechanism analysis. Base on the above analyses and the actual conditions of Zhejiang coast area, engineering and non- engineering measures are proposed for protection against super typhoon storm surge.