中文摘要：

利用敦煌双墩子戈壁试验站2008年12月1日至2009年12月31日的塔站资料,分析了该地区地气温差的概率分布、日变化、日际变化、年变化和典型天气下的变化特征。结果表明：1）地气温差变化幅度较地温和气温小,分布在-1度附近有一个非常明显的峰值,观测期间出现的最小温差为-13.78℃,最大温差为35.59℃,平均温差为4.05℃。2）温差的日变化规律性强,白天为正,夜间为负,关于12点大致对称,夜间变化幅度小,白天温差变化幅度较大。3）不同季节温差日变化趋势大致相同,但变化幅度、温差大小和温差正负转变的时间有所不同。地气温差在12月最小,6月最大,按季节划分则为夏季最大,冬季最小。4）晴天、阴天和沙尘暴天气下,地气温差的变化趋势是一致的,但变化幅度、峰值和温差正负转换的时间有其各自特殊性。

英文摘要：

Based on the micrometerology data observed at Dunhuang Gobi Station during the period from Dec.2008 to Dec.2009,we analyzed the difference between land surface and air temperature（simply as Ts-Ta）.The characteristics of the probability distribution of Ts-Ta in the arid region were calculated.The diurnal,inter-diurnal,and annual variation feature have also been analyzed.The results indicated that：（1） In this region,the range of Ts-Ta was smaller than that of surface and air temperature,near the-1℃,there was a obvious peak.During the observation,the Ts-Ta minimum was-13.78℃ while maximum was 35.59℃,and the average was 4.05℃.（2）The diurnal variation was regular,positive in daytime,negative in night and symmetric about 12：00.（3） The diurnal variations of Ts-Ta in different seasons were the same in trend,but different in range.The Ts-Ta was the highest in June and lowest in December.（4） The Ts-Ta was quite different under the different weather conditions（sunny,cloudy and duststorm）,they had their own characteristics.