天山北麓近50年气温和降水的变化特征

根据天山北麓8个气象站1961—2010年气温和降水资料，采用线性趋势分析、Mann-Kendall检验、Hurst指数等方法，分析了天山北麓气温和降水的变化特征。结果表明:（1）50 a来，天山北麓年平均气温和年降水量均呈增加趋势，其变化率分别为0.26 ℃/10 a、15.67 mm/10 a；冬季增温最为明显，升温幅度达0.49℃/10 a左右，降水倾向率表现为夏季最大，为5.44 mm/10 a；（2）年平均气温和年降水量的突变年份分别在1996年和1983年；未来两者整体上呈增加趋势；（3）极端高（低）温指数在近50 a呈现增加（减少）趋势；极端降水指数中零降水日数和最长连续无降水日数呈不同程度的递减趋势，1日最大降水量和极端强降水日数以1.36 mm/10 a和1.81 d/10 a的速率递增，各极端气候指数空间差异明显；极端气温指数与年平均气温、极端降水指数与年降水量均有很好的相关性。

Variation Characteristics of Temperature and Precipitation in the North of Tianshan Mountains in Recent 50 Years

Based on the data of daily maximum temperature, daily minimum temperature, daily mean temperature and daily precipitation at 8 meteorological stations in the north of Tianshan Mountains from 1961 to 2010, the climate change was analyzed by linear trend analysis, sliding average method, Mann-Kendall test method, Hurst index method and so on. Results showed that the average annual temperature and precipitation increased in the north of Tianshan Mountains in recent 50 years. The linear increase trends were 0.26℃/decade and 15.67 mm/decade, respectively. The warming trend was obvious in winter, showing a rate of about 0.49℃/decade, followed by autumn with a rate of 0.35℃/decade. Precipitation increment was about 5.44 mm/10 a in summer which was largest in all seasons. The abrupt examination indicated that the annual mean temperature and precipitation had the discontinuous ascension in 1996 and 1983, respectively. The future temperature and precipitation would present a trend of increase on the whole. The extreme high temperature indices increased and the extreme low temperature indices decreased. Among the extreme precipitation indices, the longest continuous days without precipitation and the days without precipitation presented diminishing trend with different degrees, while one-day maximum precipitation and extreme rainfall days presented increasing trend with a ratio of 1.36 mm/decade and 1.81 d/decade. Meanwhile, the differences in their spatial distributions were significant. The extreme temperature indices correlated with annual mean temperature, and extreme precipitation indices correlated with annual precipitation too.