Large amount of observed facts and analyses show that meteorological conditions including pressure distribution, relative humidity (upper air dew point temperature), temperature, wind speed and the variation of atmospheric stability can affect obviouly the consistency and diffusion of air pollutants, such as PM 10 , SO 2 and NO 2, with some regularities. In different seasons and different time periods, the surface and upper air meteorological factors play different roles. On the other hand, because of the variation of pollution sources with seasons and the emitted pollutant amount cannot be obtained exactly.