Abstract:This paper investigated the roughness, stability and temperature inversion (TI) properties of urban boundary layer based on the analysis of wind and temperature observations from Tianjin meteorological tower. The results indicated that there is significant roughness length and zero plane displacement in all directions of the meteorological tower under the influence of surrounding buildings. The impact of urbanization on wind field is more evident below 80 m. Affected by the diurnal variation of turbulence intensity, the diurnal variation characteristics of wind speed in the upper and lower levels of meteorological towers are obviously different in each season. Based on the temperature difference wind speed method, atmospheric stratification is found more stable in autumn and winter. The occurrence of TI is more frequent under stable conditions and both the intensity and height of TI are much larger than those under unstable and neutral conditions. Furthermore, the occurrence of TI near ground is more frequent under stable conditions, which is very favorable to severe air pollution episode. The intensity of urban heat island is correlated with the temporal distribution of atmospheric stability.