中文摘要：

基于中国国家气象信息中心发布的1961—2013年全国0.5°×0.5°逐日降水量和逐日平均气温数据集以及气象站点日降水量和气温实测资料,评估了该套格点降水资料在新疆地区的可信度,并利用格点降水资料研究了新疆地区降雪量、降雨量以及雪雨比的时空变化和突变信息。结果表明：内插到气象站点的格点降水数据和气象站点实测降水数据之间的偏差普遍较小,偏差在0.2~1.0 mm的站点个数占总站点数的72.55%,在绝大多数区域二者之间的相关系数均在0.80以上;1961—2013年,新疆降雪量呈微弱的增加趋势,增加幅度为0.11 mm·a~（-1）,但没有通过0.05的显著性水平检验。降雨量以0.63 mm·a~（-1）的速率呈明显的增加趋势（P〈0.000 1）,突变出现在1992年左右。雪雨比呈下降趋势,幅度为0.01 a-1（P〈0.05）,突变出现在1991年左右;降雪量、降雨量及雪雨比表现出一定的空间分布差异,降雪量和降雨量在全区普遍呈增加趋势,而雪雨比在天山山地以北呈增加趋势,在天山山地以及天山山地以南主要呈减少趋势。在新疆冰川分布区域,降雪量倾向率在新疆北部呈增加趋势,而在新疆东南部呈减少趋势;降雨量倾向率呈增加趋势,且新疆东南部降雨量倾向率大于北部;雪雨比倾向率呈现出与降雪量倾向率相似的变化趋势。

英文摘要：

Based on the 0. 5° × 0. 5° daily precipitation and daily mean temperature datasets and the daily precipitation and temperature datasets measured by the meteorological stations and released by National Meteorological Information Center,the credibility of gridded datasets of precipitation in Xinjiang during the period of 1961-2013 was evaluated,and the spatiotemporal changes of rainfall,snowfall and snowfall/rainfall ratio（ S/R） in Xinjiang were analyzed. The results showed that the deviation between the interpolated gridded data and the observed data was generally low. The deviation ranged from 0. 2 to 1. 0 mm at 72. 55% stations. The correlation coefficients at most stations were higher than 0. 80. Snowfall in Xinjiang was in a slight increase trend by a rate of 0. 11 mm·a~（-1）during the period of 1961-2013,but it was not statistically significant at 0. 05 level. Rainfall was in an obvious increase trend by a rate of 0. 63 mm·a~（-1）（ P 0. 000 1）,and the mutation occurred around 1992. S/R ratio was in a decrease trend by a rate of 0. 01 a-1（ P 0. 05）,and the mutation occurred around 1991. The spatial distribution of snowfall,rainfall and S/R was different,in which snowfall and rainfall were holistically in increase trends. The S/R was in an increase trend in the area north of the Tianshan Mountains,but in a decrease trend in the Tianshan Mountains and the area south of the Tianshan Mountains. In the area where modern glaciers are distributed,snowfall was in an increase trend in north Xinjiang,but in a decrease trend in southeast Xinjiang. Rainfall was in an increase trend,especially in southeast Xinjiang,and the S/R was in a trend similar to that of snowfall.