Impact of meteorological conditions on aerosol pollution over northern suburbs area of Beijing in winter

The aerosol samples and meteorological data collected during January 1~12, 2004 at Beijing meteorological tower yard were analyzed. The results show that aerosol episodes happened frequently in winter, the percentage of over national standard was 58% during the observation period. The higher concentration occurred with calm wind and bias eastern wind direction and was in company with strong lower layer temperature inversion. Stable snowfall process had delayed scavenging on PM10. The results from the binary linear regression analysis of PM10 with relative humidity and wind speed showed that wind speed had higher influence on PM10 daily averaged concentration. PM10 indicated the same characteristic of fine particles in winter. Synoptic situations had obvious influence on aerosol concentration. It is found that aerosol concentration is very high when the weather in Beijing is controlled by the high-pressure or equalizing pressure types at surface.