近50年乌鲁木齐河流域垂直气候带的异同变化特征

Similarities and Differences of Climate Change During Last 50 Years in Altitudinal Belts of Urumqi River Basin

依据乌鲁木齐河流域各站点近50a的观测数据,分析垂直带内气候变化的异同特征。结果表明,年增温趋势最强的是低山带0.554℃/10a,贡献最大是冬季温度。温度距平变化幅度除中山带为进入21世纪最大外,其他均为1990s最大。显著增温突变年际尺度(2a)上,低海拔带响应早于中、高山带;年代际尺度(16～23a)上高山带最早,中山带最晚。年增湿趋势最显著是高山带20.8mm/10a,贡献最大是夏季降水。降水距平幅度除高山带1990s振幅最大外,其他均为1980s最大。降水突变特征为随着海拔高度的增加突变的响应时间依次推后。

Based on the meteorologic data during last 50 years,this paper analyzes the characteristics of climate change in the altitudinal belts with linear tendency rate,Mann-Kendall and Wavelet of Mexican Hat. The results indicate that annual temperature increased significantly in the low mountain zone with the tendency rate of 0. 554℃ /10yr,contributed by winter warming,differing from middle mountain zone and alpine zone which were dominated by autumn warming. Besides amplitude of annual temperature departures changed most significantly in the 21th century in middle mountain zone,in other zones the annual temperature fluctuated greatest in the 1990s. Response of annual temperature jump transition in the lower zones is earlier than the middle mountain and alpine zone in the generational scale （ 2 yr） ,whereas alpine zone responded earliest in the decadal scale （ 16 -23 yr）. Annual precipitation in the alpine zone increased the most at a tendency rate of 20. 8 mm/10 yr,attributed to summer rainfall. Amplitude of annual precipitation departures fluctuated greatest in the 1980s in other zones except the alpine zone,the highest amplitude of which was in the 1990s. Response to the annual precipitation jump transition was lagged with the increase of altitude.