长三角地区夏季降水结构演变及其非平稳性  

Evolution and non-stationary characteristics of summer precipitation structure over the Yangtze River Delta

作　　者：吴雷 许有鹏[2] 王强[2] 徐羽 高斌[2] WU Lei;XU Youpeng;WANG Qiang;XU Yu;GAO Bin(College of Resources and Environment,Anhui Agricultural University,Hefei 230036,China;College of Geographic and Oceanographic Sciences,Nanjing University,Nanjing 210023,China;Department of Geography and Spatial Information Techniques,Ningbo University,Ningbo 315211,China)

机构地区：[1]安徽农业大学资源与环境学院,安徽合肥230036 [2]南京大学地理与海洋科学学院,江苏南京210023 [3]宁波大学地理与空间信息技术系,浙江宁波315211

出　　处：《水科学进展》2022年第5期730-742,共13页Advances in Water Science

基　　金：国家自然科学基金资助项目(U2240203);安徽农业大学稳定和引进人才科研资助项目(rc522013)。

摘　　要：基于长三角地区72个站点1960—2016年逐日降水量观测数据,采用Pettitt与Mann-Kendall非参数检验法,从降水量、降水日数、降水强度和不同等级降水(小雨、中雨、大雨与暴雨)发生率方面,分析长三角地区夏季降水结构的时空演变及其非平稳性特征,并探讨其可能的成因。结果表明:(1)长三角地区夏季小雨发生率以减少为主,其他6个降水指标均以增加为主。其中,小雨发生率非平稳的站点表现为单调减少,降水量、降水强度、大雨和暴雨发生率非平稳的站点表现为单调增加,并且主要分布在太湖流域,增加了该区域遭受洪涝灾害的风险。(2)东亚夏季风强度与长三角地区多数站点的小雨发生率呈正相关关系,而与其他降水指标呈负相关关系。(3)长三角地区城市化典型区(太湖流域)城市化对夏季降水量、降水强度、大雨和暴雨发生率有增加作用,贡献率分别为25.4%、27.9%、54.6%和25.5%;对降水日数、小雨和中雨发生率有减少作用,贡献率分别为-37.3%、-33.2%和-100%。This research aimed to determine the evolution and non-stationarity characteristics of summer precipitation structure over the Yangtze River Delta(YRD)in a changing environment.Based on the daily precipitation data from 72 rain gauges over the YRD during 1960—2016,the methods of Pettit and Mann-Kendall were applied to investigate the spatio-temporal variation rules of summer precipitation,considering the variables of precipitation amount,days,intensity and the incidence rates of light rain,moderate rain,heavy rain,and rainstorms,and analyze their causes.The results showed that the incidence rate of light rain decreased through time at most gauges,but the other six indices increased at most gauges.Among these,the non-stationarity in the incidence rate of light rain decreased monotonically,while the non-stationarity characteristics of precipitation amount,intensity,and incidence rates of heavy rain and rainstorms increased monotonically.These gauges were mainly scattered in the Tai Lake Basin,suggesting that this region is likely to face even greater risks from flooding.For most gauges,the intensity of the East Asian summer monsoon was positively associated with the incidence rate of light rain,but it was negatively associated with the other six indices.Take the Tai Lake basin as an example,urbanization increased the precipitation amount,intensity and incidence rates of heavy rain and rainstorms,with contribution rates of 25.4%,27.9%,54.6%,and 25.5%,respectively.However,urbanization decreased the precipitation days and the incidence rates of light rain and moderate rain,with contribution rates of-37.3%,-33.2%,and-100%,respectively.

关 键 词：降水结构 时空演变 非平稳性 长三角地区 

分 类 号：TV125[水利工程—水文学及水资源]