利用乌鲁木齐市1961-2010年逐日降水资料,采用线性倾向估计法、Mann-Kendall法等,分析了乌鲁木齐市年、各季节的总降水量和降水日数,不同量级的降水量和降水日数的变化趋势。结果表明：近50年内,乌鲁木齐市年均降水量为262.6 mm,降水日数为83.6 d,均呈上升趋势,其上升速率分别为30.4 mm/10a和1.9 d/10a;各季节中,春季降水所占比重最大,冬季最小,且春、夏、冬三季降水量极显著增加,而降水日数仅略有增加;各量级中,微量降水所占比重最大且略微减少,其余各级均有增加;年降水量和降水日数均在1979年左右有一次较为显著的增加突变;春、夏、秋、冬四季降水量分别在1968、1980、1974和1983年各有一次显著突变,而降水日数则无显著突变。
This research focused on the seasonal,annual and different levels precipitation variation tendency in Urumqi based on the daily precipitation data during the period from 1961 to 2010,and the linear tend analysis,Mann- Kendall rank statistical test were used in the study. The results showed that during the past 50 years,the annual precipitation was 262. 6 mm in Urumqi,and the days of precipitation was 83. 6 d. There was a increasing trend in annual precipitation and days,and the speeds were 30. 4 mm /10a and 1. 9 d /10a. In different seasons,the precipitation was all increased. The largest contribution for seasons was spring（ 32. 3%）,and the smallest one was winter（ 12. 5%）. For the precipitation days,they were all increased except autumn. In different levels,the amount and days of light precipitation was the biggest for annual precipitation（ 37. 8% and 63. 6%）.For both the amount and the days of precipitation,only the trace precipitation reduced slightly,the rest of precipitation levels were all increased. The significant increasing mutations of annual precipitation and days happened in 1979. The significant mutations of seasonal precipitation happened in 1968,1980,1974 and 1983.The precipitation days had no significant mutations.
Journal of Arid Land Resources and Environment