巴丹吉林沙漠东南部沙山群地区近地层湍流特征研究

Characteristics of turbulent at sand hills region in the southeastern of Badain Jaran Desert

利用巴丹吉林沙漠东南部沙山群地区涡度相关系统观测近到地层湍流资料,计算并统计了湍流方差特征,分析了湍流能谱和协谱变化特点,并讨论了湍流谱局地各向同性。结果表明:三维风速标准差与稳定度关系满足MoninObukov相似理论,温度和湿度(水汽)标准方差与稳定度的关系难以符合Monin-Obukov相似理论;Monin-Obukov相似理论对湍流能谱和协谱的基本能适用,但个别能谱存在差异;局地各向同性理论同样满足。本研究能为复杂地形下近地层湍流物质和能量输送机制提供参考。

We Calculated and analyzed the characteristics of the turbulence variance, studied the characteristics of the turbulent spectrum and co-spectrum, and discussed the turbulence spectrum local isotropy by using the data of turbulence which is observed by the eddy covariance system at sand hills region in the southeast of Badain Jaran Desert. The results show that the standard deviations of three-dimensional wind speed support the Monin-Obukov similarity theory, while the standard deviation of temperature and humidity （water vapor） fluctuation does not support the Monin-Obukov similarity theory. Both spectrum and cospectrum of turbulence appear to follow the Monin-Obukov similarity theory, yet there are individually differences in it. The velocity spectra fit lower frequency limit for isotropy. This study can provide a reference for the mechanism of turbulent transport material and energy at surface boundary layer over complex topography.