基于游程理论和两变量联合分布的中国西南地区干旱特征研究  

Research on drought in southwest China based on the theory of run and two-dimensional joint distribution theory

作　　者：左冬冬[1] 侯威[2] 颜鹏程[3] 封泰晨 

机构地区：[1]扬州大学物理科学与技术学院,扬州225002 [2]中国气象局国家气候中心,气候研究开放实验室,北京100081 [3]兰州大学大气科学学院,兰州730000

出　　处：《物理学报》2014年第23期45-56,共12页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:41305056;41175067);国家重点基础研究发展计划(批准号:2012CB955901)资助的课题~~

摘　　要：基于中国西南地区(四川省、云南省、贵州省和重庆市)89个站点1961—2010年的逐月标准化降水指数序列,利用游程理论和Copula函数分析了这一地区不同等级和不同历时干旱的出现概率及重现期特征.结果表明:西南地区的干旱事件多为历时小于4个月、强度小于3的干旱事件;月内轻旱、月内中旱、季内特旱和跨季特旱的概率较大.干旱历时小于3个月和干旱强度为中旱以下的干旱类型多出现在西南地区的东部和西部,而干旱历时大于3个月和干旱强度为重旱以上的干旱类型多出现在西南地区中部.西南地区东部和西部的重现期大于中部地区,且随着干旱历时和干旱强度的增大,重现期空间差异越明显.而且,各气候态下相同干旱类型的概率差值不大,概率波动范围为±0.05,即随着时间推移,各干旱类型出现的概率均未出现较大幅度的变化.Based on the standardized precipitation index data of 89 meteorological stations in southwest China（Sichuan Province, Yunnan Province, Guizhou Province, Chongqing） during 1961–2010, the probability and interval time were analyzed by employing the theory of run and the Copula function. The droughts with duration less than 4 months and the severity less than 3 account for 80% of all the droughts in southwest China. Drought types are mainly light within a month, moderate within a month, severe within a season and severe within inter-seasons. The frequency of occurring of drought with a duration less than 3 months and the severity less than 1 is higher in the eastern and western areas,and the central region has higher frequencies of occurrence of drought with a duration greater than 3 months and with severity greater than 1.5. Return periods of drought in eastern and western areas are longer than that of central region.More obvious spatial difference appears with longer duration and greater severity. The probability differences of the same drought type in different climatic types are within 0.05, indicating that there is no wide-range fluctuation in the occurrence probabilities of all the drought types as the time goes on.

关 键 词：中国西南地区 干旱 游程理论 COPULA函数 

分 类 号：P426.616[天文地球—大气科学及气象学]