基于连续干旱游程的干旱特征分析与应用  

An Analysis and Application of Drought Characteristics Based on Connected Drought Runs

作　　者：覃丽华 张鑫[1] QIN Li-hua;ZHANG Xin(College of Water Resources and Architectural Engineering,Northwest Agriculture and Forestry University,Yangling 712100,Shaanxi Province, China)

机构地区：[1]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《中国农村水利水电》2020年第10期164-169,共6页China Rural Water and Hydropower

基　　金：陕西省科技统筹创新计划项目(2016KTZDNY-01-01)。

摘　　要：干旱是复杂的自然灾害,了解干旱的演变规律对旱情的防治、水资源的规划和管理意义重大。根据榆林市5个气象站1960-2016年的逐月标准化降水指数,通过不连续干旱游程(UDR)与连续干旱游程(CDR)方法提取干旱变量,应用Copula函数分析干旱发生概率与重现期。结果显示:①与UDR方法相比,CDR方法提取的数据系列含有较多极端数据,有助于减小最优理论分布与实测数据的尾部拟合误差;②干旱历时与干旱烈度的联合最适分布为:绥德站为Frank Copula,榆阳站和横山站为Gumbel Copula,神木站和定边站为Gaussian Copula。③榆林市干旱联合累积概率随干旱历时与干旱烈度增大而增大;组合重现期随干旱历时与干旱烈度的增大而呈先缓后陡的增加趋势。Drought is a complicated natural disaster.It is of great significance for the prevention and control of drought,water resources planning and management to understand the evolution of drought events.According to the monthly standardized precipitation index of 5 meteorological stations in Yulin from 1960 to 2016,the drought duration and drought severity variables are extracted by Unconnected Drought Runs(UDR)and Connected Drought Runs(CDR)methods.The Copula function is used to analyze the joint probability and return period of drought duration and drought severity.The conclusions are as follows:①Compared with the UDR method,the data extracted by the CDR method contains more extreme data,which helps reduce the tail fitting error between the optimal theoretical distribution and the measured data;②The optimal joint distribution of drought duration and drought severity is:Suide Station is Frank Copula,Yuyang Station and Hengshan Station are Gumbel Copula,Shenmu Station and Dingbian Station are Gaussian Copula.③The joint cumulative probability of drought in Yulin increases with the increase in drought duration and drought severity.The return period increases with the increase in drought duration and drought severity in a slow then steep trend.

关 键 词：榆林 干旱 连续干旱游程 COPULA 

分 类 号：TV93[水利工程—水利水电工程] P429[天文地球—大气科学及气象学]