摘要
通过分析2010-2018年天津气象塔风、温度资料,对近年来天津城市边界层粗糙度、大气稳定度和逆温特征进行研究。结果表明:随着城市发展,气象塔周边各方向粗糙度和零平面位移明显增高,气象塔周边建筑物对80 m高度以下风场的影响较为明显。受湍流强度日变化影响,各季节中气象塔高层和低层风速日变化特征差异明显。通过温差-风速法计算大气稳定度发现稳定类层结多出现在秋冬季的夜间,稳定层结条件下逆温情况多发,其逆温强度、逆温层厚度和贴地逆温比例也明显高于不稳定和中性层结。天津城市热岛强度的时间分布表现出夜间强于白天,秋冬季强于春夏季的特征。城市热岛强度与大气稳定度时间分布具有一定相关性。
This paper investigated the roughness,stability and temperature inversion(TI)properties of urban boundary layer based on the analysis of wind and temperature observations from Tianjin meteorological tower.The results indicated that there is significant roughness length and zero-plane displacement in all directions of the meteorological tower under the influence of surrounding buildings.The impact of urbanization on wind field is more evident below 80 m.Affected by the diurnal variation of turbulence intensity,the diurnal variation characteristics of wind speed in the upper and lower levels of meteorological towers are obviously different in each season.Based on the temperature difference-wind speed method,atmospheric stratification is found more stable in autumn and winter.The occurrence of TI is more frequent under stable conditions and both the intensity and height of TI are much larger than those under unstable and neutral conditions.Furthermore,the occurrence of TI near ground is more frequent under stable conditions,which is very favorable to severe air pollution episode.The intensity of urban heat island is correlated with the temporal distribution of atmospheric stability.
作者
刘敬乐
姚青
蔡子颖
韩素芹
李英华
杨健博
郝囝
LIU Jingle;YAO Qing;CAI Ziying;HAN Suqin;LI Yinghua;YANG Jianbo;HAO Jian(Tianjin Key Laboratory for Oceanic Meteorology,Tianjin 300074;Tianjin Institute of Meteorology,Tianjin 300074;Tianjin Environmental Meteorological Center,Tianjin 300074;CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research,Tianjin 300074)
出处
《气象》
CSCD
北大核心
2020年第9期1235-1244,共10页
Meteorological Monthly
基金
天津自然科学基金项目(17JCQNJC08200)
国家自然科学基金项目(41771242)
天津市生态环境治理科技重大专项(18ZXSZSF00160)
天津市科技支撑项目(09ZCGYSF0210)
中国气象局预报员专项(CMAYBY2019-007)共同资助。
关键词
粗糙度
大气稳定度
逆温
气象塔
天津
aerodynamic roughness
atmospheric stability
temperature inversion
meteorological tower
Tianjin