中文摘要：

利用中国气象局成都高原气象研究所在青藏高原东坡理塘地区建立的大气综合观测站观测资料,以2006年1月和7月涡旋相关资料分别代表冬季和夏季,分析和比较了该地区近地层包括风速、风向、大气稳定度在内的平均场特征,以及湍流强度、无量纲化风脉动方差相似性和地表通量变化特征。结果表明,1月和7月稳定度基本集中在±0.5和±0.25之间;湍流在〈2 m·s^-1的风速环境中发展最为旺盛,随着风速的增大湍流强度减小迅速;无量纲化三维风脉动方差符合Monin-Obukhov相似理论的＂1/3＂定律,其最佳通用相似函数在稳定和不稳定条件下都可以拟合得到;地表通量均表现出明显的日变化特征,1月以感热为主,潜热很小;7月以潜热为主,感热较小。

英文摘要：

A comprehensive field experiment of atmospheric boundary layer over grassland surface is introduced. The experiment has been held in Litang region on the east edge of Tibetan Plateau by IPM, CMA （Institute of Plateau Meteorology, China Meteorological Administration） since November 2005. Some micrometeorological characteristics of wind speed, wind direction, atmospheric stability, and turbulent intensity, variance similarity, surface fluxes in the near-surface layer are analyzed and compared based on the observational data acquired by using the eddy correlation method in January and July 2006 （representing winter and summer, respectively）. The main results are as follows： Atmospheric stability mostly varies from -0.5 to 0.5 in January, from -0.25 to 0.25 in July. Turbulence is very active when wind speed is less than 2 m · s^-1 and decreases rapidly as wind speed increasing. The normalized variance of three-dimensional winds and z/L satisfies the similarity law under both unstable and stable stratification, their universal functions also can be fitted according to the ＂law of 1/3 fractional power＂. The diurnal variations of surface fluxes are evident, and sensible heat flux is leading, latent heat flux is very weak in January while reversely in July.