Ozone in Beijing area: observations in 2000

The vertical observations of O3 and NOx were implemented in Beijing in summer of the year of 2000. The measurements, based on the observation platforms of the 235-m meteorological tower of LAPC, Institute of Atmospheric physics, CAS, were made at the height of 2m, 15m, 50m, and 80m, respectively. The synchronous meteorological observations at 15 instrumented platforms, which are located at 8, 15, 32, 47, 63, 80, 100, 120, 140, 160, 180, 200, 240, 280m, inculde wind velocity, wind direction, temperature and humidity. Analysis of ozone concentration and relevant meteorology are conducted. The peak ozone over 100ppb(v) were frequently observed during the experiment campaigns, and maximum ozone concentration is obtained at the height 120m other than at the surface where NOx is emitted by heavy traffic in Beijing. Relativity between ozone and its precursors NO2、NO is statistically analyzed based on the vertical observations. The annually overall oberservation of air pollutants in Beijing implies that heavy smog air pollution in winter is mainly resulted from coal burning, but high level of oxidants in summer is highly related to vehicle exhausts.