根据河西走廊地面气象观测时间最长的敦煌、瓜州、玉门、酒泉、高台、张掖、山丹、武威、民勤9个站的水汽压观测资料，运用线性回归、小波和Mann-Kendall方法对绿洲农作区近地面水汽变化特征进行趋势、周期及突变分析。结果表明：近60 a河西走廊绿洲农作区近地面水汽均呈波动上升趋势，线性递增率为0．123 hPa·10a-1。夏、秋两季上升幅度最大，线性递增率分别为0．192 hPa·10a-1和0．198 hPa·10a-1，春季递增率仅为0．056 hPa·10a-1属最小；年水汽变化存在3 a主周期和30 a较长主周期，还有10 a较弱周期。春、夏季水汽变化有5 a主周期和20～30 a左右的较长周期尺度；秋季水汽变化有5 a主周期，还存在30～40 a长周期；冬季水汽变化存在5 a周期，随着时序延长，周期也在延长，2000年以后有15 a周期。年水汽含量在1985年出现突变；春季水汽含量在1980年出现突变；夏季水汽含量在1986年出现突变；秋季水汽含量1994年出现突变；冬季水汽含量在1983年出现突变。水汽含量对气候变暖响应明显，年、季水汽压与平均气温之间相关显著，年平均、春、夏、秋、冬季相关系数分别为0．592、0．192、0．551、0．532、0285。说明河西走廊年、夏、秋、冬季近地面水汽变化与河西走廊平均气温有显著正相关。%Using the linear regression,wavelet analysis and Mann-Kendall methods,we carried out the trends,cy-cles and mutation analysis for the water vapor changing characteristics in near-surface of the oasis agricultural areas,ac-cording to the observed water vapor pressure information come from the nine stations of Dunhuang,Guazhou,Yumen,Ji-uquan,Gaotai,Zhangye,Shandan,Wuwei and Minqin,which had the longest ground meteorolocial observations in the Hexi Corridor .The results shown that:In recent 60 years,the near-surface water vapor pressure in the oasis agricultural areas of the Hexi Corridor has been shown a wavy increasing trend,the linear increase was 0 .123 hPa·10a-1 .The maxi-mal rise extent was in summer and autumn,with the linear increasing rate was 0.192 hPa·10a-1 and 0.198 hPa·10a-1, respectivesly .The minimal increasing rate was in spring with the rate only 0 .056 hPa·10a-1 .The yearly water vapor change existed a 3-year main cycle and a 30-year longer main period,also a 10-year weaker cycle .In spring and summer season,there was a 5-year main cycle and a 20~30-year longer period cycle for the water vapor change scale .In autum, there was a 5-year main cycle,also existed a 30~40-year longer cycle .The water vapor change in winter also existed a 5-year cycle,but with the time sequence extended,the cycle was extended too .there was a 15-year cycle after 2000 . The yearly water vapor content was emerged mutation in 1985,For the four seasons as spring,summer,autum and win-ter,the water vapor content was emerged mutation in 1980,1986,1994 and 1983,respectively .The response of water vapor content to climate warming was apparent .There were statistically significant correlations between annual and sea-sonal water vapor pressure with the mean temperature .The correlation coefficients in annual mean,spring,summer,au-tum and winter were 0.592,0.192,0.551,0.532 and 0.285,respectively.This indicated that the near-surface water vapor changes was sgnificant positive correlation with the mean temperature in Hexi Corridor .
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