摘要
利用1960~2014年中国西南地区141个气象台站的逐日气象资料,引入一个新的干旱指数——逐日标准化降水蒸散指数（日SPEI）,对极端干旱事件的年代际、年际、季节内变化及持续性特征进行了分析,结果表明：空间上,近55 a西南春季和年极端干旱程度呈一致的减弱趋势,重庆、四川与贵州的交界处及四川西北部极端干旱程度明显缓解,而夏、秋两季极端干旱表现出增强的趋势并有一定的区域性特征。时间上,春季和全年极端干旱频率、强度和持续天数逐渐减少,春季极端干旱的减弱程度较全年明显;夏、秋两季极端干旱频率、强度和持续天数呈增加趋势,夏季极端干旱的加重趋势比秋季明显。从极端干旱事件的持续性来看,20世纪60年代和21世纪初（2000~2014年）西南遭受的极端干旱最严重,持续期达60 d以上的站点分别占到站点总数的60%和73%。
Abslraet： The quantification of drought frequency, duration, intensity, and changes in areal-extent over time is not only essential in the drought risk management making process, but also combat of extreme drought hazard making. However, the current common drought indices can only identify average drought severity over a drought period and cannot indentify drought characteristics at short time scales. The climatic condition in southwestern China, largely an agricultural region, has been considerably variable in the past several decades. Drought has occurred more frequently and has become one of the most serious hazards in the last and current century in Southwest China. The extreme drought events frequently occur, as drought events have taken place in Southwest China. The present study aims to assess the changes in Southwest China＇s extreme drought events in 1960-2014. Using daily meteorological data collected from 141 stations across the Southwest China from 1960 to 2014, the daily Standardized Precipitation Evapotranspiration Index（daily SPEI） is developed based on daily meteorological data in this study. Latency evaporation is calculated by Penman-Monteith method, from inter-decadal, inter-annual, inter-seasonal variability, persistent characteristic of extreme drought events ana- lyzed over Southwest China in past 55 years by daily SPEI index. The results showed that： From the point of view of space trends to see, it displayed consistent decreased extreme drought trend in spring and whole year over Southwest China in past 55 years. The Chongqing, on the border between Sichuan and Guizhou, north- west of Sichuan are the areas in which severity of extreme drought events has significantly decreased in the past 55 years. But it displayed increased extreme drought trend along with regional extreme drought trend fea- ture in summer and autumn. The frequency, intensity and duration of extreme drought events have significantly increased on the border among of Sichuan, Guizhou, Yunnan, and Chongqing in summe
作者
贾艳青
张勃
Jia Yanqing1,2, Zhang Bo2(1. Department of Geography, Xinzhou Normal University, Xinzhou 034000, Shanxi, China; 2. College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, Gansu, Chin)
出处
《地理科学》
CSSCI
CSCD
北大核心
2018年第3期474-483,共10页
Scientia Geographica Sinica
基金
国家自然科学基金项目(41561024)
山西省高等学校哲学社会科学研究项目(2015265)资助~~
关键词
极端干旱事件
日SPEI
中国西南
extreme drought events
daily SPEI
the Southwest China
