摘要
利用"城市气象/示踪外场试验"期间(2011年10月1-14日)在兰州市榆中县城区获取的观测资料,分析了城区内的湍流统计特征和地表能量收支状况.结果表明,白天城区内大气为中等不稳定层结,而夜间则接近于中性;计算的无量纲相似关系式与其他城市的结果较为一致;反照率日变化呈现非对称U型结构,日出日落时刻反照率较大,白天较小且接近于常数0.14.白天能量输送以感热为主,感热和潜热占净辐射的比例分别为23%和2%,波文比为11.白天热储量占净辐射的比例高达75%,而夜间两者大小相当.夜间热储量的释放可以抵消甚至超过损失的长波辐射,从而促进城市热岛现象的发生.
The statistical characteristics of turbulence and surface energy budget in urban areas were analyzed using the experimental data obtained from Urban Meteorological and Tracer Experiment （UMTE 2011） conducted in Yuzhong County during October 1 to 14, 2011. The results showed that the atmospheric stratification was moderate unstable at daytime, while it was close to neutral at night; the calculated non-dimensional similarity relations were consistent with previous results in other cities; the diurnal surface albedo had an asymmetric ＂U＂-shaped pattern, and the albedo at sunrise and sunset was larger than that at daytime, which was close to the constant value of 0.14; the energy transfer between the urban surface and atmosphere was dominated by a sensible heat flux, and the ratio of the sensible （latent） heat flux to the net radiation was 23% （2%） and the Bowen ratio was 11 in daytime. It was particularly noticeable that the ratio of the storage flux to the net radiation was 75% in daytime, and the latter was equal to the former at night. The loss of long-wave radiation could be offset by a release of heat storage at night, which contributed to the formation of the urban heat island.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2018年第1期112-119,共8页
Journal of Lanzhou University(Natural Sciences)
基金
国家重点基础研究发展计划项目(2011CB706903)
国家自然科学基金面上项目(41275019
41475009)
中央高校基本科研业务费专项资金项目(LZUJBKY-2016-196)
关键词
城市下垫面
外场观测试验
湍流特征
能量通量
urban underlying surface
field experiment
turbulence characteristic
energy flux
