北京及周边地区典型站点近地面O_3的变化特征

Variation characteristics of surface O_3 in Beijing and its surrounding area

利用2008年6月1日～2009年5月31日在北京城区中国气象局(CMA),及其西南方向固城站(GCH)和东北方向上甸子本底站(SDZ)的近地面O3等观测数据,分析了O3的变化特征及其与其他污染物和气象要素的关系.结果表明,上甸子本底站近地面O3的季节变化和日变化规律与固城和北京城区站存在一定的差异,而固城站和北京城区站的O3变化特征差异较小.相关性分析显示,O3与NO、NO2、NOx、RH多呈负相关,且相关性冬季好于夏季,此外,O3与气温和风速呈正相关,其中北京城区站冬季和夏季O3与风速的相关性差异最明显.O3浓度与地面风向有一定关系,当风向为偏南时,O3浓度较高,当风向为东北时,O3浓度偏低.

Surface O3 and other pollutants were observed from June,2008 to May,2009 simultaneously at the compound of China Meteorological Administration（CMA） in Beijing urban area,Shangdianzi background station（SDZ） northeast of Beijing,and Gucheng station（GCH） southwest of Beijing.The observational data are used to study the variation characteristics of surface O3 and the relationships between O3 concentration and other pollutants concentrations as well as meteorological parameters.The results show that surface O3 at SDZ has clear seasonal and diurnal cycles,which are obviously different from those at other two stations,while the seasonal and diurnal cycles at GCH and CMA are similar.O3 is negatively correlated with NO、NO2、NOx、RH,and the correlations in winter are more significant than in summer.In addition,air temperature and wind speed are positively correlated with O3,and the correlation coefficient between wind speed and O3 at CMA changes very much from winter to summer.The O3 concentrations show some dependence on the local wind direction at the sites,with higher O3 concentration being observed under southerly winds and lower O3 concentration under northeasterly winds.