摘要
利用云南124个测站1961—2005年4—5月的月降水量及气温资料，采用EOF方法及离散功率谱方法，分析了云南4—5月的降水总量及平均气温的时空变化特征及其变化周期，得到了如下结论：（1）降水场与温度场具有相似的空间分布特征，全省一致性分布型。这种分布型存在明显的年际变化特征，500hPa环流差异明显。（2）全省平均降水量与平均温度具有明显的年际变化特征。1963年是近45年中的降水最少年，2004年则是降水最多年。1969年是近45年平均气温最高年，1990年则是气温最低年。（3）全省平均降水量与平均温度也具有明显的年代际变化特征。20世纪60和90年代高温低湿；70和80年代低温高湿；2001年以后转入高温高湿。2005年春末夏初的干旱就是发生在高温高湿气候背景下的较为异常的气候事件。（4）降水量存在明显的2—3年左右的年际变化周期，同时也存在明显的15年的年代际变化周期。平均气温2～5年左右的年际变化较为明显，而较长时间的年代际变化周期较弱。
Using the data on monthly precipitation and temperature at 124 stations of Yunnan Province in April - May, 1961 -2005 and EOF method as well as discrete power spectral method, the characteristics of spatial and temporal distribution and the change periods of total precipitation and average temperature of Yunnan in April - May were studied. The results indicate that ： （ 1 ） The precipitation field and temperature field of Yunnan in later spring and early summer （April - May） have similar spatial distribution and distribution has obvious interannual change feature. The 500 height field hase obvious difference. （2） The average precipitation and average temperature of Yunnan in April - May have obvious interannual change feature. The least average precipitation among near 45 years appeared in 1963 and the most appeared in 2004. The highest average temperature among near 45 years appeared in 1969 and the lowest appeared in 1990. （3）The average precipitation and average temperature of Yunnan also have obvious interdecadal change feature. There is a high temperature and low moisture climate of Yunnan in 1960＇ s and 1990＇ s and a low temperature and high moisture in 1970＇ s and 1980＇ s. The climate of Yunnan turns into high temperature and high moisture after 2001. In this high temperature and high moisture climatic background, the severe drought of Yunnan took place in 2005. （4） There are obvious interannual oscillation period of 2 ~ 3 years, and interdecadal oscillation period of 15 years in average precipitation. There is obvious interannual oscillation period of 2 -5 years in average temperature and its longer interdecadal oscillation period is very feeble.
出处
《自然灾害学报》
CSCD
北大核心
2009年第1期124-132,共9页
Journal of Natural Disasters
基金
国家973重点基础研究发展规划项目(2003CB415100)的资助
关键词
干旱
空间分布
年际变化
年代际变化
周期
云南省
drought
spatial distribution
interannual change
interdecadal change
period
Yunnan Province
