摘要
全球变暖增加了极端气候事件的发生概率,复合极端事件比单个极端事件对社会经济与环境造成的影响更严重。基于中国639个气象站点1961-2020年逐日降水和最高气温数据,采用加权平均降水指数(WAP)和相对阈值法识别出洪水和热浪事件,分析中国7日内洪水-热浪复合极端事件总频次及发生概率等时空变化特征,对比不同时段单个极端事件与复合事件两者之间变化差异,并探讨了洪水-热浪中热浪最长持续时间和平均强度变化,为我国防洪减灾方案提供参考。研究结果表明:(1)近60年几乎所有站点都发生过洪水-热浪复合极端事件,并表现出明显空间差异,出现频次较高的区域主要分布在长江流域、东南诸河流域、珠江流域及内陆河流域;(2)1961-2020年洪水-热浪事件总频次及中国区域平均发生概率均呈显著上升趋势(P<0.01),且不同年代以来上升速率越来越大;不同年份复合事件出现的频次和概率差异较大,2016年频次、概率最高(261次、17.4%),1985年频次、概率最低(8次、0.5%),发生概率与频次呈现出高度一致性;(3)与单个发生的极端事件相比,洪水-热浪复合事件发生频次增幅更大,1981-2000年、2001-2020年洪水-热浪事件总次数与1961-1980年的比值由1.26增加至2.96,且在长江流域东部、珠江流域东南部及东南诸河流域表现最为突出;(4)与热浪前没有洪水的热浪事件相比,洪水-热浪事件中热浪的最长持续时间相对较短、平均强度相对较小,不同流域空间差异表现不明显。
The probability of extreme climate events is increasing under global warming,and compound extreme events have more serious im⁃pacts in society and environment than individual extreme events.By using daily precipitation observation and daily maximum temperature da⁃ta from 639 meteorological stations over China during 1961-2020,this paper adopts the index of weighted average of precipitation(WAP)and the method based on relative threshold to identify flood and heatwave events,and investigates total frequency and probability of com⁃pound extreme flood-heatwave events occurrence within seven days,discusses the temporal variation characteristics of compound events in the different periods compared with individual extreme events,and analyzes the duration and average magnitude of heatwave in flood-heat⁃wave event,this study can provide reference for the flood control and disaster reduction scheme in China.The research results are as follows:①In recent 60 years,the compound flood-heatwave events occur at almost all stations,and show obvious spatial differences.The regions with high frequency of compound extreme events occurrence are mainly distributed in Yangtze,Southeast,Pearl and Northwestriverbasins;②The total frequency and the regional average occurrence probability of flood-heatwave events over China showed significant increasing trends(P<0.01)from 1961 to 2020,which became larger and larger among different decades.The frequency and probability of compound events occurrence in different years varied greatly with the highest values in 2016(261 times,17.4%)and the lowest values in 1985(8 times,0.5%),and the frequency and probability of occurrence has significant correlation;③Compared with individual extreme events,the increasing rate of flood-heatwave events is relatively significant.The ratio of the total number of flood-heatwave events during 1981-2000 and 2001-2020 against the total frequency of compound events during 1961-1980 increased from 1.26 to 2.96,and the increasing rate was most prominent in e
作者
刘慕嘉
杨秀芹
姚飛
张洁
张余庆
LIU Mu-jia;YANG Xiu-qin;YAO Fei;ZHANG Jie;ZHANG Yu-qing(chool of Hydrology and Water Resources,Nanjing University of Information Science and Technology,Nanjing 210044,Jiangsu)
出处
《中国农村水利水电》
北大核心
2023年第4期167-176,共10页
China Rural Water and Hydropower
基金
国家自然科学基金资助项目(41907384)。
关键词
复合极端事件
频次与概率
热浪持续时间与强度
时空变化特征
中国
compound flood-heatwave events
frequency and probability of occurrence
duration of heatwave and average magnitude
spa⁃tial-temporal characteristics
China
