Air Pollution Characterictics Of Beijing City In Summer

Based on the Beijing 325m meteorological tower ,Five levels data of ozone,NOx concentration and meteorological parameters were measured in summer in 2002.they were analyzed detailed and drawn the conclusion about the significant characteristics of pollutants and their relationship with meteorological parameters.The main results are shown as follows:First,a brief introduction of a series of experiments is given.These experiments are based on the advanced instruments of LAPC.Then the characteristics of pollutants were analyzed:ozone concentration varied remarkably in summer in Beijing ,it's concentration is very low at night,then rise quickly at daytime and reach peak at afternoon.the characteristic of ozone changes with weather .In cloudy and rainy days,the curve of ozone concentration is more complex than that in sunny days and the numerical value is also lower.The ozone concentration varied remarkably on difference levels.the curves of ozone concentration mostly are single peak,two peaks is observed only in one rainy day.The characteristic of NOx concentration is simple with two peaks.Based on those research,the relationship of ozone and meteorological parameters is analyzed, the results indicate that temperature has the most closely relationship with ozone,it reach the peak almost at the same time with ozone,or 1 to 2 hours late.Humidity has less effect than temperature.When humidity has a large range,it can has effect on ozone concentration.they have negative correlation.Ozone concentration in one part also affected by wind.Finally ,the relationship of ozone and NOx is analyzed.the ozone concentration increased with the decreasing of NOx,but they aren't linear relationship.As fas as Beijing city,it indicate that ozone concentration is not only affected by NOx,but also by other environmental parameters.