新疆区域面雨量分布特征及其变化规律

Characteristics of Area Precipitation in Xinjiang Region with Its Variations

将自然正交分解(EOF)和数字高程模型(DEM)相结合,利用新疆区域144个气象站和水文站的1961—2005年降水量资料,计算得到新疆区域面雨量年、季分布特征和变化规律。分析结果表明:新疆区域年平均面雨量约为2724.6×108t,年平均降水量为165.5mm。从空间分布来看,天山山区面雨量最大,约占全疆面雨量的40.4%,该区域年平均降水量为409.1mm;北疆地区次之占34.3%,年降水量为277.3mm;南疆地区最少约为25.3%,年平均降水量仅有66.2mm。从季节分布来看:夏季面雨量最大,约占全年面雨量的54.4%;春季次之为23.6%;秋季为16.5%;冬季最少,约为5.5%。新疆区域面雨量年际变化呈现出增多的趋势,1987年存在突变,在此之后降水量明显增多。

Using the data of precipitation including 144 meteorological and hydrological stations in Xinjiang from 1961 to 2005, annual and seasonal distributing features and its variations of area precipitation in Xinjiang are discussed by empirical orthogonal function （EOF）, multiple regression analysis, maximum entropy analysis and so on, combining with 1 kin× 1 km gridding data of digital elevation model （DEM）. Results show that mean annual area precipitation in Xinjiang region is 2724.6 × 10^8t and mean annual precipitation is 165.5 mm. For space distribution, area precipitation of Tianshan Mountains, Northern Xinjiang and Southern Xinjiang respectively occupy about 40.4% , 34.3% and 25.3% of all regions, and its mean annual precipitation are 409. 1 mm, 277.3 mm and 66.2 mm, respectively. Area precipitation in summer is the most one about 54.4% of all year, 23.6% in spring, 16.5% in autumn, and the least 5.5% in winter. In the last 45 years area precipitation in Xinjiang presents clear annual variations and increasing trend, especially since 1987.