基于Copula函数的雷州半岛气象干旱风险分析  

Analysis of Meteorological Drought Risk in Leizhou Peninsula Based on Copula Function

作　　者：张得胜 江涛[2] 黎坤[2] 蒋可元 单云龙 ZHANG Desheng;JIANG Tao;LI Kun;JIANG Keyuan;SHAN Yunlong(Comprehensive Technology Center of Pearl River Water Resources Commissionof the Ministry of Water Resources,Guangzhou 510611,China;School of Geography and Planning,Sun Yat-Sen University,Guangzhou 510275,China;Technical Consultation Center of Pearl River Water Resources Commissionof the Ministry of Water Resources,Guangzhou 510611,China)

机构地区：[1]水利部珠江水利委员会珠江水利综合技术中心,广东广州510611 [2]中山大学地理科学与规划学院,广东广州510275 [3]水利部珠江水利委员会技术咨询中心,广东广州510611

出　　处：《人民珠江》2019年第9期110-120,共11页Pearl River

摘　　要：选取雷州半岛作为研究区域,基于区内12个雨量站1966—2015年逐月降雨序列数据,采用6个月时间尺度的标准化降水指数,结合旋转经验正交分解法对区域气象干旱分布进行空间模态分解,并运用G-HCopula函数建立不同空间模态干旱历时与干旱烈度的二维联合分布模型,对雷州半岛气象干旱风险进行分析。结果表明:雷州半岛干旱空间分布可分解成5个空间模态,不同模态对应不同区域,第一空间模态的荷载中心区域位于徐闻大部分区域、第二空间模态的荷载中心位于雷州西部地区、第三空间模态的荷载中心位于湛江市区、第四空间模态的荷载中心位于遂溪西部地区、第五空间模态的荷载中心位于遂溪的东南部及雷州的东北部地区;以100、50、20、10、5、2a共6个重现期为衡量标准,不同区域之间的干旱历时与干旱烈度联合分布“或”与“且”两种重现期基本接近,反映雷州半岛不同区域出现干旱事件的风险概率基本相同;不同空间模态2年一遇“或”重现期风险率最高,介于53%~56%之间,2年一遇“且”重现期风险率最高,介于44%~50%之间,显示出2年一遇干旱属于雷州半岛主要的干旱事件;对干旱遭遇条件概率和组合条件概率进行分析,显示出在2~6个月干旱历时条件下,2年一遇的干旱烈度是影响区域的主要干旱事件,进一步表明雷州半岛干旱发生频率高。Based on monthly rainfall series data covering the period of 1966-2015 from 12 precipitation stations in Leizhou Peninsula (selected as the research area),this paper conducts spatial mode decomposition of regional meteorological drought distribution by combining the standardized precipitation index of 6 month scale with the rotated empirical orthogonal function method,and establishes a two-dimensional joint distribution model of drought duration and intensity in different spatial modes based on G-H Copula function to analyze the meteorological drought risk in Leizhou Peninsula.The results show that:① The spatial distribution of drought in Leizhou Peninsula can be decomposed into five spatial modes,and different modes correspond to different areas.The load center of the first spatial mode is located in most areas of Xuwen,that of the second spatial mode is in the western area of Leizhou,the third spatial mode is located in the urban area of Zhanjiang,the fourth spatial mode is in the western area of Suixi,and the fifth spatial mode is in the southeast area in Suixi and the northeast area of Leizhou.②With the return periods of 100,50,20,10,5 and 2 years as the measurement standard,the joint distribution of drought duration and drought intensity in different areas is basically similar under “or” and “and” returnperiod,reflecting that the risk probability of drought events in different areas of Leizhou Peninsula is basically the same.③The 2 year frequency of “or” returnperiod in different spatial modes shows the highest risk rate,between 53% and 56%,and the 2 year frequency of “and”returnperiod also shows the highest risk rate,between 44% and 50%,indicating that 2-year-frequency drought is the main drought events in Leizhou Peninsula.④By analyzing the conditional occurrence and combination probability of drought,it is found that the drought intensity in 2 year frequency is the main drought event in the affected area under 2 to 6 months of drought duration,further indicating that Leizhou Penins

关 键 词：气象干旱 标准化降水指数 旋转经验正交分解 COPULA函数 干旱风险 雷州半岛 

分 类 号：P429[天文地球—大气科学及气象学]