摘要
利用1961—2012年中国西南地区86个气象站逐月降水量和平均气温资料,引入一个新的干旱指数——标准化降水蒸散指数(SPEI)作为干旱等级划分指标,研究了1961—2012年该地区不同时间尺度干旱的变化特征。结果表明:该地区12个月尺度干旱频率在云贵交界区呈显著增加趋势,其他区域变化不显著且不一致;少雨期(11—4月)6个月尺度干旱频率在全区显著增加,而在多雨期(5—10月)大部分区域干旱频率呈缓慢减少趋势,减少最明显的区域在四川南部;3个月尺度干旱频率在春季变化不明显,在秋季和冬季显著增加,其中2000—2012年的增加趋势尤为显著,干旱化趋势严重。
The characteristics of different timescale drought variations from 1961 to 2012 in Southwest China were studied, by using a new drought index （standardized precipitation evapotranspiration index, SPEI） as the division standard of droughts. The level was calculated based on the monthly precipitation and average air temperature data from 86 meteorological stations. The results show that the drought frequency at 12-month timescale presents a significant declining trend in theYunnan-Guizhou border zone, but an inconsistent and unclear trend in other regions. The drought frequency at 6-month timescale shows a significant increasing trend in the dry period （November April in the following year） in the whole research area, but a slowly decreasing trend in the rainy period （May October） in most regions, particularly in southern Sichuan. The drought frequency at 3-month timescale does not indicate a significant trend in spring, but shows a significant increasing trend in autumn and winter, especially in 2000 2012.
出处
《气候变化研究进展》
CSCD
北大核心
2013年第3期192-198,共7页
Climate Change Research
基金
国家公益性行业(气象)科研专项(GYHY201006023
GYHY201106034)
"中央高校基本科研业务费专项基金"自由探索项目(lzujbky2012-123)
关键词
西南地区
标准化降水蒸散指数(SPEI)
多时间尺度
干旱频率
Southwest China
standardized precipitation evapotranspiration index （SPEI）
multiple timescale, droughtfrequency
