天山天格尔山南北坡降水特征研究

Precipitation Variations on the Southern and Northern Slopesof the Tianger Range in Tianshan Mountains

对新疆天山天格尔山南北坡乌拉斯台河和乌鲁木齐河流域及其山前平原不同高度气象(水文)站近40a降水实测资料的统计分析,研究天山天格尔山南北坡不同坡向及高度的降水特征.结果表明:山区降水远大于山前平原,南北坡降水均呈现为增加趋势,冬季和夏季降水的增加趋势明显;山前平原区降水的年际变化幅度大于山区;冬、春季降水变率大于夏、秋季,南坡降水变率远大于北坡,冬、春季表现地尤为突出.年际降水的减少趋势出现在乌鲁木齐河流域中山峡谷地带的英雄桥水文站,其春季3月份的降水量减少趋势非常显著;乌鲁木齐河源大西沟气象站4～5月和6～8月月降水呈明显的反相关变化.

Based on monthly and annual precipitation data of the southern and northern slopes of the Tianger Range in Tianshan Mountains, the spatial-temporal variations of precipitation and the major changing trend are analyzed. Monthly precipitation is considered separately. The analyzed Precipitation series ranging from the 1950s to 2002 are collected from nine meteorological and hydrological stations, which scatter all over the southern and northern slopes of the Tianger Range in Tianshan Mountains. A statistical analysis shows that the increasing trend of precipitation is very obvious in the northern and southern slopes. The variable coefficient of precipitation is larger in the southern slope than in the northern slope, as such it is larger in winter and spring than in summer and autumn. There is a decreasing trend of the precipitation at Yingxiongqiao Hydrological Station in the rümqi River valley. The trend in March is more distinct, with a trend coefficient of -0.325. There is a significant inverse correlation between April to May and June to August at the Da Xigou Weather Station in the headwaters of the rümqi River, with correlation coefficients of -0.475 and -0.376, respectively.