三种干旱指数在山西省干旱分析中的比较  

Comparision of Three Drought Indices in Drought of Shanxi Province

作　　者：杨世刚[1,2] 杨德保[1] 赵桂香[3] 付亚平[2] 武捷[4] 

机构地区：[1]兰州大学大气科学学院,甘肃兰州730000 [2]山西省雷电防护监测中心,山西太原030002 [3]山西省气象台,山西太原030006 [4]山西省气象信息中心,山西太原030006

出　　处：《高原气象》2011年第5期1406-1414,共9页Plateau Meteorology

基　　金：中国气象局预报员专项CMABY2011-005资助

摘　　要：利用1957-2003年山西省30个测站逐月、逐年降水量、平均气温资料、降水距平百分率、帕尔默指数和Z指数等三种干旱指数的计算方法和判定标准,分别在山西省北部、中部、南部和全省的旱涝状况进行判定的基础上,对三种干旱指数的判定结果进行了比较和相关分析。结果表明:(1)从旱涝年发生频次来看,降水距平百分率判别干旱的趋势可信度最高,帕尔默指数次之,Z指数相对较低;(2)在干旱强度判定方面,Z指数判定的干旱级别比降水距平百分率指数偏大二个级别,比帕尔默指数偏大一个级别。帕尔默指数判定干旱的强度比较符合实际;(3)降水距平百分率直观地表现了自然降水的多寡对造成旱涝的影响,Z指数更适用于反映单站的旱涝变化,P指数描述干旱强度方面更占优势。Using the monthly and yearly precipitation data at 30 weather stations in Shanxi Province during 1957-2003 and three drought indices,namely the precipitation anomaly percentage（R′ index）,Z index and Palmer index calculated drought conditions of the northern,central and the southern part of Shanxi Province and the whole province.The determination of the three indices were compared and analyzed.The obtained results are as follows（1） comparing with the occurrence frequency of flood and drought years,the credibility of the drought trend judged by R′ index is the highest,P index is second,Z index is relatively low;（2） the drought intensity grade determined by Z index is two grade as well as R′ index and one grade as well as Palmer index.The drought intensity determined by Palmer index relatively conform to realisty;（3） the R′ index directly expression the impact of amount of rainfall on drought and flood,Z′ index is more suitable for a single station to reflect changes in drought and flood.P index has more advantage in describe the intensity of the regional drought.

关 键 词：山西省 降水距平百分率 帕尔默指数 Z指数 

分 类 号：P462.3[天文地球—大气科学及气象学]