Impacts of Atmospheric Particles on Surface Ozone in Nanjing
南京地区大气颗粒物影响近地面臭氧的个例研究

By analyzing surface meteorological observations and air quality monitoring data (O3, NOx, and PM10) at two stations from 2 April to 7 April 2008, in Nanjing, eastern China, the inverse correlation between O3 and particulate matter is determined. A photochemical box model is employed to interpret the possible mechanism. The simulation shows that elevated concentration of particulate matter can increase the aerosol optical depth by 20%-40% and reduce averaged photolysis rates of NO2 and O3 and concentration of OH and HO2 by 20%-30% and 20%-50%, respectively, which leads to a 30%-40% decrease in the net photochemical production rate of O3. The results indicate that the effects of atmospheric particles on photochemistry and the oxidation ability of the atmosphere are responsible for the reduction of the observed surface O3 concentration.