北京地区一次特大强风过程边界层结构的研究

A Study of the Structore of a Strong Wind Event in the Atmospheric Boundary Layer in Belting Area

利用北京３２５ｍ气象塔资料对１９９３年４月９日北京地区出现的一次特大强风过程的边界层结构（风、温、风切变及阵风特征）进行了分析。随着该次大风的过境，边界层内风场出现数个风速高值中心，高度位于２００～３００ｍ，时间间隔１～３ｈ。伴随上层风速垂直切变和阵风特性。湍流能谱的计算结果表明了大尺度涡旋对边界层湍流微结构的影响。

Using the data of the 325 m Beding Meteorological Tower, the structures of wind and temperature of a strong wind event occurred in the Beijing area on April 9, 1993 are analyzed. During the passage of the strong wind, the wind field in the boundary layer appeared several maximum regions at the 200～300 m level with time intervals of 1～3 h. Accompanying those at the upper level, there apPeared very strong wind vertical shear and wind gustness in the lower layer, whiCh also fluctuated with time. The temperature field appeared several inconsistent 'turning' with time. All these reflect the special structure in the boundary layer during the approaching of a severe weather. The result of turbulent spectra shows that during the strong wind, the contributions of vortexes on different scales to turbulent energy at different heights are not the same, which reflects the influence of large scale vortex on the fine structure of turbulence in the atmospheric boundary layer.