1970-2019年黄浦江上游年最高潮位变化及驱动因子

Changes and driving factors of annual highest tidal level in the upper reach of Huangpu River between 1970 and 2019

黄浦江年最高潮位变化关系到上海市的防洪安全。本文基于米市渡站1970-2019年年最高潮位及太湖流域降水量等数据,研究了近50年来黄浦江上游年最高潮位的变化趋势、变异特性、发生频率变化和潮位变化的驱动因子。结果表明:年最高潮位在1970-2019年总体呈显著上升趋势,上升幅度为81 cm,年均上升1.62 cm。1995年之后出现跳跃式的波动上升,1996-2002年相对1995年之前出现较大幅度上升,2003-2011年相比1996-2002年出现较明显下降,之后又较大幅度上升。随着潮位升高,各频率对应的最高潮位均大幅度增加,升高幅度均达0.9 m以上,五十年一遇、百年一遇、千年一遇高潮位分别由1970年条件下的3.77 m、3.81 m、3.94 m升高到2019年条件下的4.71 m、4.75 m、4.92 m。与此同时,相同潮位下的重现期急剧减小,高潮位发生频率大幅度增加。分析认为,黄浦江上游年最高潮位升高受气候变化和人类活动的综合影响,1970-1995年主要受降水量变化等气候因素的影响,1996-2019年主要受水利工程、台风频率增加等因素的影响,尤其是太湖流域太浦河等工程的修建起到了重要作用。

The change of annual highest tidal level of Huangpu River is key to the flood control and safety of Shanghai.Based on the data of annual highest tidal level at Mishidu station and precipitation of Taihu Lake Basin in 1970-2019,frequency of typhoon and sea level rise,this paper studies the trend,variation characteristics,frequency variation and driving factors of annual highest tidal level in the upper reach of Huangpu River in the last 50 years.The results show that the annual highest tidal level has a significant rising trend between 1970 and 2019,with total rise of 81 cm and annual average rise of1.62 cm.After 1995,the tidal level rises with obvious fluctuations:jump rise during 1996-2002 compared with before 1995,distinct decline during 2003-2011 compared with period 1996-2002,and then significant rise again.With the rise of tidal level,the highest tidal levels corresponding to the same frequencies increase significantly by more than 0.9 m for all frequencies.The high tidal levels with return periods of 50 years,100 years and 1000 years increase from 3.77 m,3.81 m and3.94 m under conditions of 1970 to 4.71 m,4.75 m,and 4.92 m under conditions of 2019 respectively.At the same time,the return periods for the same tide levels decrease sharply,and the frequencies of high tidal levels increase greatly.The analyses show that the rise of annual highest tidal level is affected by the climate change and human activities in combination.In1970-1995,the variation of precipitation is the main factor.During 1996-2019,the rise of the highest tidal level is mainly induced by water conservancy projects and increased frequency of typhoon.Especially the project of Taipu River and other projects in Taihu Lake Basin are the important factors.