1961~2020年三峡区间降水极值特征分析  

Characteristics of Precipitation Extremes in Three Gorges Reservoir Intervening Basin During 1961-2020

作　　者：李帅 陈鲜艳[2] 龚文婷 申赵勇 朱文丽 LI Shuai;CHEN Xian-yan;GONG Wen-ting;SHEN Zhao-yong;ZHU Wen-li(China Three Gorges Corporation,Yichang 443133,China;National Climate Center,Beijing 100081,China)

机构地区：[1]中国长江三峡集团有限公司,湖北宜昌443133 [2]国家气候中心,北京100081

出　　处：《长江流域资源与环境》2022年第10期2166-2175,共10页Resources and Environment in the Yangtze Basin

基　　金：国家自然科学基金项目(52109024);长江水科学研究联合基金项目(U2040218)。

摘　　要：为探明三峡区间极端降水变化规律,基于三峡区间18个气象站点1961~2020年的逐日降水数据,首先选取7个常用的极端降水指数,分析三峡区间降水极值的时空变化规律。然后,基于年最大值(AM)法和超门限阈值(POT)法筛选降水极值样本序列,利用广义极值分布(GEV)和广义Pareto分布(GPD)拟合两组样本序列。基于Kolmogorov-Smirnov检验结果确定最优拟合分布函数,并根据最优拟合分布函数推求不同重现期水平下的降水量。结果表明:(1)三峡区间江北降水极值整体强于江南,江北开州站为三峡区间降水极值中心。(2)GEV分布适合拟合AM序列,GPD分布适合拟合POT序列,基于GEV-AM和GPD-POT组合得到的不同重现期水平的降水量空间分布相似,但基于AM序列推算一定重现期水平下的降水极值更大。研究成果可为三峡水库防洪调度及三峡库区地质灾害防治提供一定参考。In order to explore the characteristics of precipitation extremes in the Three Gorges Reservoir Intervening Basin(TGRIB),based on the daily precipitation data(18 rain gauge stations) in the TGRIB during 1961-2020,seven extreme precipitation indices were firstly selected in this paper to investigate the tempo-spatial variations of extreme precipitation in the TGRIB.Two extreme precipitation series were then filtered from the 60 years of precipitation data at 18 stations using the annual maximum(AM) and peak-over-threshold(POT) method,and the generalized extreme distribution(GEV) and generalized Pareto distribution(GPD) were used to fit the two precipitation series and to investigate their statistic characteristics.The best distribution was determined by the Kolmogorov-Smirnov test and then the best distribution was used to estimate the precipitation extremes in different return periods.The results showed that:(1) the precipitation extremes in the north bank of the Yangtze River were greater than those in the south bank,the Kaizhou station is the peak of extreme precipitation in the TGRIB.(2) the optimal distribution for the AM series were GEV distribution,and the best distribution for the POT series were GPD distribution.The distributions of precipitation extremes in different return periods derived from two combinations of GEV-AM and GPD-POT were similar,but the estimated precipitation amounts by the GEV-AM combination were larger than that of the GPD-POT combination in the different return periods.It provides a certain reference for the flood control operation of the Three Gorges Reservoir and the prevention and control of geological disasters in the TGRIB.

关 键 词：降水极值 极端降水指数 极值分布 三峡区间 60年 

分 类 号：P333.9[天文地球—水文科学]