摘要
降水时域集中特征研究对流域抗旱防涝至关重要。基于长江流域1960~2020年气象站点降水数据计算降水集中度(PCD)与集中期(PCP)指数,采用滑动t检验、交叉小波变换与小波相干分析等方法,检测降水集中指数序列突变点,分析突变前后降水集中程度时空变化特征,并揭示降水集中指数对遥相关因子的响应。结果表明:①PCD与PCP突变节点约为1988年,突变前后PCD和PCP空间上皆大致呈由东南向西北递增的趋势,突变后流域年内降水分配趋向于均匀坦化且集中期提前。②PCD、PCP与太平洋年代际振荡(PDO)、北极涛动(AO)、厄尔尼诺(ENSO)、太阳黑子(SS)存在共振周期,其中PDO和ENSO与PCD和PCP共振相互作用更加显著,表明该遥相关因子可能是导致长江流域降水特征突变的重要因素之一。研究成果可为长江流域灾害防治、生态保护、水资源管理等工作提供技术支撑。
Characteristics of precipitation temporal concentration are important for drought and flood prevention in watershed.Based on the precipitation data of meteorological stations in the Yangtze River Basin from 1960 to 2020,the index of precipitation concentration degree(PCD)and precipitation concentration period(PCP)were calculated.The moving t-test,cross-wavelet,and wavelet-coherence analysis were used to identify and test the abrupt change of precipitation temporal concentration index sequence,and the spatiotemporal characteristics of PCD,PCP and their response to teleconnection factors were analyzed.The conclusions are as follows:①The abrupt changes of PCD and PCP in the Yangtze River Basin occurred around 1988.The PCD and PCP were generally incremented from southeast to the northwest before and after the mutation.After the mutation,the intra-annual precipitation distribution tended to be uniform,and the precipitation concentration period was advanced.②There was a resonance period between PCD,PCP,and PDO(pacific decadal oscillation),AO(Arctic oscillation),ENSO(El Nino)and SS(sunspot).PDO and ENSO interacted more significantly with PCD and PCP,indicating that these teleconnection factors may be one of the important factors leading to the abrupt changes of precipitation concentration characteristics in the Yangtze River Basin.The research results can provide technical support for disaster prevention,ecological management and water resources management in the Yangtze River Basin.
作者
曹青
刘康龙
黄潇
郝振纯
CAO Qing;LIU Kanglong;HUANG Xiao;HAO Zhenchun(School of Hydrology and Water Resources,Nanjing University of Information Science&Technology,Nanjing 210044,China;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China)
出处
《人民长江》
北大核心
2023年第5期121-126,174,共7页
Yangtze River
基金
国家自然科学基金青年科学基金项目(42201025)
江苏省高等学校基础科学(自然科学)研究项目(21KJB570012)
水利部水文气象灾害机理与预警重点实验室开放基金项目(HYMED202210)。
关键词
降水集中度
降水集中期
突变检验
遥相关因子
长江流域
precipitation concentration degree
precipitation concentration period
abrupt change test
teleconnection
Yangtze River Basin
