上海地区洪涝致灾因子复合概率及未来变化分析

根据上海地区三阶段(1970-2004年,2020-2054年和2060-2094年)四要素(降水、吴淞口风速、太湖流域面雨量、吴淞口潮位)提取年极值时间序列,采用GEV分布首先开展"雨洪风潮"各致灾因子气候变化分析,结果显示:"雨洪风潮"各致灾因子年极值受气候变化影响均呈增加趋势;进而基于Copula联合函数中的三维变量的超越概率模型,计算"雨洪风""雨洪潮"和"雨风潮"三种"三碰头"联合超越概率,结果表明:未来气候变化时段相对于历史基期,上海地区"雨洪风""雨洪潮"和"雨风潮"三种三碰头概率呈增加趋势。洪涝灾害致灾因子同时发生的复合概率增加,预示着气候变化影响下上海地区防汛排涝安全存在更大风险。

Analysis on the Compound Probability and Future Change of Flood and Waterlogging Disaster Factors in Shanghai

According to the time series by extracted annual extreme values of four elements(precipitation,wusong wind speed,surface rainfall in taihu lake basin,and wusong mouth tidal level)in the third stage of Shanghai area(1970-2004,2020-2054 and 2060-2094),first,the single-factor climate change analysis of“rainstorm or flood or wind or tide”was carried out based on the GEV distribution,it showed that the annual extreme value of the single factor of“rainstorm or flood or wind or tide”is increasing under the influence of climate change.Then,the transcendental probability model of the three-dimensional variables in the Copula function is used to calculate the joint probability of“rainstorm-flood-wind”,“rainstorm-flood-tide”and“rainstorm-wind-tide”,the results show that the probability of“rainstorm-flood-wind”,“rainstorm-flood-tide”and“rainstorm-wind-tide”increases in the future climate change period compared with the historical base period in Shanghai.The increase in the Composite probability of simultaneous occurrence of flood and waterlogging disaster factors indicates that there are greater risks in flood control and drainage safety in Shanghai under the influence of climate change.