中国东部地区城市化对气温影响的观测分析

Observation analysis of urbanization effect on surface air temperature trends in East China

现有场地观测表明,城市化对于气温的影响在静风、无云条件下的晚上最明显,而在大风、多云条件下的晚上最小。本文采用一套经过均一化处理的中国地区逐日平均、最高以及最低气温序列资料集,分析了中国东部地区在不同风速、云量条件下地面气温变化的趋势。结果表明,从1960—2008年,中国东部地区(20～45°N,110～125°E)由于城市化造成的气温增暖为0.03℃/10a。而从1979—2008年,由于城市化造成的气温增暖为0.66℃/10a。在中国东部地区以及不同纬度带的3大城市群区,即京津唐、长江三角洲和珠江三角洲城市群区,城市化导致的增暖都在夏季最小。

Based on the results of the field observation experiments that the influence of urbanization on air temperatures reached the greatest on calm,cloudless nights and is reduced in windy,cloudy conditions,homogenized daily minimum temperature datasets for the period 1960—2008 at meteorological stations over East China are analyzed separately for windy,cloudy and calm,cloudless conditions,and their trends are compared.There is a weak tendency of more warming in calm,cloudless days than in windy,cloudy days in East China（20-45 °N,110-125 °E）,the difference 0.03℃ per decade is attributable to urbanization.Furthermore,the urban caused warming from 1979 to 2008 is estimated to be 0.66℃ per decade.The warming caused by urbanization is always found to be smallest in summer in both East China or areas of city agglomeration,such as Jingjintang area,Yangtze River delta and Pearl River delta.