北京冬季城市热岛特征及强弱热岛影响因子研究  

Research on the characteristics of Beijing winter UHI and the influencing factors of a strong UHI and a weak one

作　　者：李兴荣[1,2,3] 胡非[1] 舒文军[4] 

机构地区：[1]中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室 [2]深圳市气象局,深圳518008 [3]中国科学院研究生院,北京100049 [4]北京市气象局气候中心

出　　处：《中国科学院研究生院学报》2007年第4期431-438,共8页Journal of the Graduate School of the Chinese Academy of Sciences

基　　金：国家自然科学基金重点项目(40233030);北京市气象局城市气象科学基金(UMRF200509)资助

摘　　要：应用北京地区地面气象观测站1990～2004年1月的气温资料，分析了近15a北京冬季城市热岛的特征和变化趋势，也分析了城市热岛强度与地面气温的关系．结果表明：夜间城市热岛要强于白天，近15a夜间城市热岛具有增强趋势，而白天这样的趋势不明显．夜间月平均城市热岛强度与月平均气温正相关，气温高的年份，热岛强度相对也大，白天这种相关不明显．此外，对比分析了冬季强热岛和弱热岛的特征及其气象影响因子．结果表明：强热岛出现于夜间，白天热岛不明显；夜间强热岛出现和维持是多种因子综合作用的结果．白天日照充足的晴夜北京城郊地面风场很弱（≤2．0m／s），多个测站甚至出现静风，同时城区垂直方向近地大气层持续存在很弱（≤2．0m／s）的风场，甚至静风，城区320m高度以下持续存在大气逆温，有利于冬季强热岛的形成和维持．晴朗白天即使近地层大气风速维持在2．5m／s以下，城市热岛也会减弱消失，太阳辐射的加热作用所引起的郊区地面大气升温速率和幅度大于城区，近地面大气稳定度的变弱，以及城区大气逆温的消失是城市强热岛减弱并最终消失的重要原因．Based on the data of 20 meteorological stations from 1990 to 2004, the characteristics of Beijing urban heat island in the last 15 a were analyzed. The results show that the UHI in the evening is stronger than that in the daytime. The UHI in the evening tends to get stronger year by year, but is not obvious in the daytime. In the evening, the higher the average monthly surface temperature is, the stronger the average monthly UHI is. But in the daytime the correlativity is not so obvious. Furthermore, with the additional data obtained by two automatic meteorological stations and the 325m meteorological tower of LAPC, the characteristics and influencing factors of a strong UHI and a weak UHI in winter were analyzed contrastively. And the results show that the cooling rate of the suburban surface atmosphere is bigger than that of the urban surface atmosphere after sunset, which directly leads to the formation of the strong UHI. And the heating rate of the suburb surface atmosphere is bigger than that of the urban surface atmosphere after sunrise, which directly causes the weakening and disappearance of the strong UHI. In the clear night of the sunny day, the occurrence and maintenance of the weak wind （ ≤ 2.0m/s） below 100m and the inversion temperature below 320m have important effects on the formation and maintenance of the strong UHI. And in the daytime the solar radiation has most important effects on the weakening and disappearance of the strong UHI. It makes the suburban surface atmosphere temperature rise faster than the urban atmosphere temperature, and makes the inversion temperature disappear, and further makes the strong UHI weaken and disappear at about 2：00 p.m. in the end even if the wind remains weak in the daytime.

关 键 词：城市热岛 强热岛 晴天 弱风 逆温 

分 类 号：P468-322.1[天文地球—大气科学及气象学]