近50年开都河流域下游降水和气温变化特征分析

摘要

Through the data of air temperature and precipitation from 1960 to 2009 at the three stations of Yanqi,Hejing,and Heshuo County,and using methods of linear fitting and Mann-Kendall test,seasonal and annual changes of air temperature and precipitation in lower reaches of Kaidu River Basin were characterized in this study.The results indicated that:(1) Annual average temperature of these three counties showed an escalating trend.The linear fitting growth rates of these three counties are 0.366 ℃· 10a-1,0.256 ℃· 10a-1 and 0.033 ℃· 10a-1.(2) Mean maximum temperature and the mean minimum temperature of Yanqi and Hejing County showed an ascending trend,while monthly mean minimum temperature in Heshuo county showed a decreasing trend.As for as seasonal and annual temperature alternations are concerned,seasonal temperature of all these three counties showed an increasing trend.Temperature increase in winter is significant.The inter-annual alternation extent of fall average temperature is at same range of inter-annual alternation of annual average temperature.(3) Annual precipitation anomalies of three counties appeared down-up-down trend.(4) Lapse rate was abnormal in three counties,and precipitation rate was abnormal in Yanqi county.Abrupt atmospheric temperature change occurred frequently and all of them ocurred in the 1990s.%采用开都河流域下游焉耆县、和静县、和硕县三个气象站1960-2009年气温和降水观测资料,以线性趋势函数,M-K突变检验等方法,分析开都河流域下游气温和降水的年际变化、季节变化特征.研究结果表明:(1)焉耆县、和静县与和硕县的年平均气温呈上升趋势,年平均气温线性拟合增长率分别为0.366℃·10a-1、0.256℃·10a-、0.033℃·10a-1.(2)和硕县月平均最低气温呈现下降趋势,而焉耆县与和静县平均最高气温、最低气温均呈上升趋势；从季节年际变化来看,三个县四季气温均有增加趋势,冬季增温明显,秋季平均气温的年际变化幅度与年平均气温的年际变化幅度相似.(3)三个县年降水量距平值呈下降-上升-下降特征,降水量有微弱增多趋势.(4)和静县与和硕县两站气温异常,焉耆县降水异常,气温突变均出现在20世纪90年代,而且突变发生较频繁.