基于PDSI的长江中下游地区干旱分布特征  

Aridity Characteristic in Middle and Lower Reaches of Yangtze River Area based on Palmer Drought Severity Index Analysis

作　　者：王文[1] 许志丽[1,2] 蔡晓军[1] 高晶[3] 

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室,大气科学学院,南京210044 [2]内蒙古气象科学研究所,呼和浩特010051 [3]内蒙古气候中心,呼和浩特010051

出　　处：《高原气象》2016年第3期693-707,共15页Plateau Meteorology

基　　金：国家自然科学基金项目(41275091);干旱气象科学研究基金(IAM201302);南京信息工程大学科研基金项目

摘　　要：利用1961-2012年长江中下游地区90个测站逐日降水、气温等观测资料,建立长江中下游地区的帕默尔旱度模式,并利用此模式计算出52年90个测站逐月PDSI指数,与资料记载的实际旱涝灾情对比并分析了长江中下游地区的旱涝特征。结果表明,修正的帕默尔旱度模式能准确反映长江中下游地区的干旱过程,与实际旱涝发生时间、持续时段、旱涝严重程度及旱涝发生范围对应比较吻合,对旱涝的反应比较灵敏;长江中下游地区旱涝年际变化显著,夏、秋季旱涝具有连续性,干旱具有3个月的持续期;冬季存在较弱的年代际变化,而夏季年代际变化较为明显;长江中下游地区夏秋季干旱多发,极端干旱在秋季较多,安徽西部及北部、浙江北部、湖南西南部是干旱较容易发生的区域,而极端干旱多发生于安徽阜阳和宁国、湖南衡阳和郴州、浙江慈溪和定海以及湖北巴东等地。To evaluate the ravages of a drought in middle and lower reaches of Yangtze River area,a farther modified Meteorological Drought Severity Model was developed based on the Palmer Drought Severity Model.The conventional precipitation and temperature data in 90 stations were used as basic data（1961-2012） to establish the Palmer drought index in middle and lower reaches of Yangtze River,with this modified index we have calculated the monthly drought index for 90 stations in the middle and lower reaches of Yangtze River area,we compared with the situation of drought and waterlog recorded in documents and analyzed the characteristics of the drought and waterlog.It is found that the farther modified Palmer Drought Severity Model can reflect the severity of meteorological drought comparatively and be consistent with the actual onset time,duration time,the severity of droughts and floods and regions where droughts and floods occur,it is sensitive to droughts and flood;there is a marked interannual variation of drought in the middle and lower reaches of Yangtze River area and the drought has duration of three months;Interdecadal variation is obvious in Summer while weaker in Winter;Drought often happened in west and north of Anhui,north of Zhejiang and northwest of Hunan in summer and autumn,extreme drought mostly happened in Fuyang,Ningguo,Hengyang,Chenzhou,Cixi,Dinghai and Badong in autumn.

关 键 词：干旱 Palmer指数 长江中下游地区 时空分布 

分 类 号：P42[天文地球—大气科学及气象学]