西安气温日变化特征的城郊差异

Diurnal Temperature Variation Characteristics of Urban and Rural Areas in Xi'an

为了研究城市化对西安气温日变化的影响,利用西安及其郊区站咸阳1961—2013年4次气温的观测资料,采用城郊对比法对西安和咸阳2个站气温的年、季节、6 h变温、昼夜温差的变化特征进行对比分析,揭示城市化对西安气温日变化特征的影响。结果表明:(1)西安市气温的变化无论哪个时次都高于咸阳且呈上升趋势,2时西安气温的上升幅度最显著,0.56℃/10 a,14时西安与咸阳气温变化趋势基本一致;(2)西安城市气温上升变化幅度从1990s中期开始明显增大,且城市季节变化趋势最明显的是春季,其次是冬季,夏季变化最小,咸阳气温变暖趋势明显滞后于西安5~8年;6 h气温变化温幅度最大的是早晨到中午这个时段,最小的是夜间到早晨。

Based on the observation data of temperature four times per day in Xi＇an and Xianyang from 1961- 2013, the characteristics of annual and seasonal temperature, and variation of 6 hours temperature and nightday temperature difference were analyzed by comparing the changes of temperature in Xi ＇ an and Xianyang, to study the impact of urbanization on daily variation of surface air temperature. The results showed that： （1） no matter at what time, the temperature in Xi＇ an was higher than that in Xianyang and had an increasing trend, there was a maximum increasing rate （0.56℃/10 a） of temperature at 2 o＇ clock in the morning, and the changing trend of temperature at 14 o＇ clock in Xi＇ an was consistent with that in Xianyang; （2） the amplitude of the temperature rise was significantly increased after the middle of 1990s, and the obvious seasonal change of temperature was in spring in Xi＇ an, then was in winter, and the minimum seasonal change was in summer; the warming trend in Xianyang was lagged for 5-8 years compared with the trend in Xi＇ an, the variation of temperature of 6 hours was the maximum from morning to noon, and the minimum from night to morning.