Abstract:

The characteristic of the urban boundary layer in Beijing city has been analyzed during strong wind weat her,with the observational data of the wind speed,temperature from the Beijing 325m meteoro-logical tower. We have obtained the following results about the gust structure of the urban boundary layer.(1) The vertical mean wind profiles fits the logarit hmicrule with the height up to more than 150m during strong wind weat her. That maybe is because of the large surface roughness length over urban surface, which makes a stronger interaction between the strong wind and the surface roughness elements;(2) The gust coefficient is larger in the surface,and deceases with the height by negative exponential function;(3) The gust intensity deceases with the height by the negative exponential function also,while its decrease rate is smaller than that of the gust coefficient .

Key words: urban boundary layer, gustst ructure, strong wind weat her