Acta Scientiarum Naturalium Universitatis Pekinensis

Previous Articles     Next Articles

An Observation Study of Turbulent Flux Measured on Tower in Hilly Area, Central China

WANG Xue1, CAI Xuhui1, KANG Ling2, ZHANG Hongsheng3, SONG Yu1, CHEN Jiayi1   

  1. 1 .Department of Environmental Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871;2. State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871; 3. Department of Atmospheric Sciences, School of Physics, Peking University, Beijing 100871;
  • Received:2009-03-22 Online:2010-01-20 Published:2010-01-20



  1. 1. 北京大学环境科学与工程学院环境科学系, 北京100871; 2 .北京大学环境模拟与污染控制国家重点联合实验室, 北京100871; 3. 北京大学物理学院大气科学系, 北京100871;

Abstract: An observation tower was erected on Xiaomo Mountain, Hunan Province. Besides the collection of turbulence information, routine meteorological data were collected during 2006. Diurnal variances of wind and temperature profiles in winter and summer were analyzed as well as seasonal variances of wind speed and wind direction. Furthermore, sensible heat fluxes calculated using classical flux-profile relationship (Hc) are compared with the directly measured values (Hm) . It is found that the complexterrain around the tower has a distinct impact onthe values of roughness length z0 and calculated sensible heat flux (Hc); therefore it is necessaryto divide the data into 2-3 groups according to the wind directions. The following analysis show that z0 in the south part of the tower is much higher because of the hilly terrain, and the mountain slope affects the sensible heat flux remarkably. When upslope wind blows, the value of Hc is higher than Hm, and vice versa. Since the trend of the mountain is southwest-northeast, the value of Hc is similar to Hm whenthe windis fromsouthwest. Finally, Hc is corrected and the agreement between Hc and Hm is largely improved.

Key words: turbulent flux, profile, tower observation, complexterrain

摘要: 利用2006年湖南小墨山地区的塔层数据和湍流数据, 分析了该地区风速风向的年变化以及冬夏两季风温廓线的日变化规律, 利用传统近地层通量廓线关系得出了感热通量计算值, 并将其与感热通量测量值进行了对比, 对经典近地层相似性理论在非均匀下垫面上的应用进行了初步探讨。研究发现小墨山地区的复杂地形对粗糙度、感热通量的计算有重要影响, 需要将来流分成不同方 向分别讨论。由于北部平原南部 山地的影响, 偏南风时粗糙度z0 大于偏北风。而对夏季感热通量的分析表明, 感热通量的计算主要受到山体的影响。北风时测点位于迎风坡, 计算值系统偏大, 东南风时对应背风坡的情况, 计算值系统偏小, 西南风与山体走向大体平行, 计算值与测量值近似相等; 将有偏差的计算值进行修正后, 结果得到了明显改善。

关键词: 湍流通量, 廓线, 塔层观测, 复杂地形

CLC Number: