全球变暖背景下天山地区近地面水汽变化研究

Research on Change of Surface Water Vapor in the Tianshan Mountains under Global Warming

利用天山地区44个站1961-2009年水汽压数据,采用线性趋势估计、距平分析、Mann-Kendall趋势统计突变检验和功率谱等方法,分析天山地区近地面水汽变化及其与区域气候变化的关系。结果表明:天山地区近49 a来水汽总体呈增多趋势,年和四季水汽变化具有年际和年代际差异,最大增多趋势均出现在20世纪90年代中后期至21世纪初,最小值出现在70年代中后期和80年代中期,最大值出现在21世纪初。突变和周期分析得出,水汽年变化与西北地区气候变化趋势具有明显一致性。年降水变化与水汽相关最高,温度和青藏高原指数次之,其他因子相关一般。

In this paper,the change of surface water vapor was analyzed using the linear trend estimation,anomaly analysis,Mann-Kendall sharp change test and power spectrum analysis based on the data of water vapor pressure at 44 meteorological stations in the Tianshan Mountains during the period from 1961 to 2009.The results show that the change trend of surface water vapor in the Tianshan Mountains was significant,and the average change trend was 0.015.There were the obvious inter-annual and inter-decadal differences in variation and change trend of annual and seasonal surface water vapor,the highest increase occurred in the late-1990s,the minimum in the late-1970s and mid-1980s,and the maximum in the early 21st century.The increase trend of surface water vapor was the most significant in summer,then in autumn and winter,and the minimum increase occurred in spring.Sharp changes of the annual and seasonal surface water vapor occurred in 1986（especially in summer and autumn）,1980（winter） and 1996（spring）.The test shows that all the sharp changes were significant（r=0.05）.The power spectrum analysis shows that there were the obvious periodicities in annual and seasonal surface water vapor change.The obvious annual periodicities of surface water vapor change were for 3.2 years and 2.9 years;the summer ones for 2.9 years and 2.3 years,and autumn ones for 3.6 years and 3.2 years.The change trend and sharp change of surface water vapor in the Tianshan Mountains were similar to the change trends of mean annual temperature and precipitation,westerly circulation,Qinghai-Tibetan Plateau circulation NAO and the time of their sharp changes.The correlation between annual precipitation and water vapor was the closest,and followed by temperature and other factors.