近54年长治地区干旱分析

Analysis of Drought in Changzhi Area in Recent 54 Years

利用长治地区11个气象观测台站1960—2013年逐月降水资料,运用小波分析、突变分析、主分量分析等方法,对近54年来长治地区干旱事件的时空异常分布和变化特征等进行了综合分析。结果表明,近54年来长治地区降水的分布特征是东少西多,区域内干旱频繁;长子县是长治地区干旱发生最为频繁、也是近年来旱情趋于严重的地区。从长治降水变化的分布型来看,全区一致旱涝的分布型占主要地位,其所贡献的方差达总方差的70%以上。长治地区降水存在着年代际变化(周期为准4~14年)和年际变化(周期为准2~4年)2个显著的振荡特征;1972—2013年长治地区降水有逐渐减少的趋势,且从1972年开始可能出现了趋于明显减少的气候突变。

Based on the monthly precipitation data of 11 meteorological observatories in Changzhi area from 1960 to 2013,the temporal and spatial anomalies and the change characteristics of drought events in Changzhi area were analyzed by wavelet analysis,mutation analysis and principal component analysis etc.. The results showed precipitation distribution characteristics of Changzhi area presented more in the west part and less in the east part,and drought was frequently happened in this region. The situation in Zhangzi County was most serious and the drought frequency was the highest. From the distribution of precipitation change in Changzhi area,it showed that about 70% of the region had the situation of both drought and flood were existed. Two obvious oscillation characteristics,which were decade variability( a cycle of 4-14 years)and yearly variability( from 2-4 years) existed in the rainfall in Changzhi area. There was a trend that rainfall decreased gradually during1972-2013. Moreover,we could say that an obvious climate change in the aspect of rainfall decrease had occurred from 1972.