鉴于北京城市大气边界层物理过程的重要性，本项目基于北京城市高密度建筑群下垫面和以农田为主的低密度建筑下垫面的香河郊区两个观测站长期连续观测数据的积累，对湍流观测数据进行严格的质量控制，重点分析平均时间对城市和郊区不同下垫面和不同观测高度通量计算结果的影响，确定最佳平均时间。获取高质量的湍流数据后，分析不同稳定条件下,尤其是稳定层结下两个观测站点大气边界层湍流输送特征。最后结合AERONET大气光学厚度和大气可降水量实时监测数据以及MODIS总云量卫星资料分析城郊两站点地表能量平衡特征差异成因。

The study on the physical process in the Beijing urban atmospheric boundary layer is very important. Based on the long-term continuous observation data over two sites in Beijing (high-density buildings over the underlying surface) and Xianghe (cropland with low-density buildings), the post-processing and quality control of the eddy covariance data will be made, especially the analysis on the influence of the different averaging time on computing the turbulent fluxes. After these corrections, we will study the characteristics of the turbulent transport under different stabilities over these two sites, especially under the stable conditions. And then contrasting characteristics of the surface energy balance will also be analyzed and explained by using various datasets (aerosol optical depth and precipitable water on AERONET, and the cloud fraction product from MODIS).