利用新疆地区89个气象站和38个水文站1961-2005年的降水资料,对比分析了这两类降水观测资料在表征新疆地区降水的时间演变特征上所存在的差异,进而探究了造成这种差异的原因,并在此基础上研究了增暖背景下新疆地区降水与地形(包括海拔高度、坡度和坡向)的关系。研究发现:1)从区域平均来看,水文站观测的年降水量(221.4mm)明显高于气象站的观测值(152.1mm),其差值为69-3mm,但是二者具有相同的时空变化特征:2)气象站与水文站降水均值之间的差异,主要受海拔高度的影响,坡度和坡向的影响次之。新疆地区地形地貌复杂,降水时空变化较大,观测数据分布不均匀均可导致对降水的估算存在较大差异,因此多源降水数据相互融合是客观估算该地区降水量及其变化的一个途径。
Based on monthly precipitation datasets of 89 meteorological stations and 38 hydrological rain gauges from 1961 to 2005 in Xinjiang, China, differences in temporal-spatial variations of Xinjiang precipitation detected by these two precipitation observations have been compared and causations for these differences have been analyzed. Meanwhile, the relationships between precipitations with topography features (altitude, slope, and aspect) under increasing warming background have been discussed. The results indicate that: 1) Multiyear mean annual precipitation in Xinjiang observed by hydrological rain gauges is 221.4 ram, which is 69.3 mm more than that observed by meteorological stations (152.1 mm). However, meteorological and hydrological observations show the same spatial-temporal change characteristics; 2) Differences between meteorological and hydrological observations are mainly affected by altitude. Besides, slope and aspect are also crucial factors. Precipitation shows huge spatial-temporal variations in Xinjiang because of complicated landform. As a result of uneven distribution of rainfall gauges, there exists great bias in precipitation estimation. In the future, it would be an effective method to objectively assess precipitation in Xinjiang that multi-source precipitation datasets combine together.