Abstract:

There were three greenhouse gases observation sites in Taiyuan, Datong and Linfen in Shanxi Province, and the continuous measurements of O3, NOX, NO2, NO and CO were carried out from 2012. Based on the observation data of O3 and its precursors from the three observation sites in summer of 2012, the characteristics and the temporal variations of ozone and its precursors were analyzed firstly, and the meteorological factors influencing ozone concentration were discussed. The results showed that both of the one-hour concentration and the daily maximum 8-hour concentration of ozone exceeded the Ambient Air Quality Standard (GB3095-2012) 2 grade in three cities, and in summer the most serious pollution of ozone occurred in Linfen, while the lowest pollution occurred in Datong. The diurnal variations of O3 concentration in three sites presented mono-peak pattern with the peak value occurring around 15:00 and the minimum value occurring around 06:00, while the variation trends of the precursors were negatively correlated with O3 concentration. Comparatively, temperature was the most important factor influencing O3 concentration among the meteorological factors, and then down to relative humidity and wind speed. The high O3 concentration was mostly accompanied by high temperature and low relative humidity in the early afternoon in summer. The affecting degree of meteorological factors on O3 concentration was different in each site.

Key words:  , ozone；precursors；meteorological factors；variation characteristics

摘要：

利用2012年夏季山西省太原、大同、临汾3个温室气体观测站的近地面O3及相关前体物NOx、NO2、NO、CO观测数据及同期气象观测资料，分析山西省夏季O3体积分数与污染状况、O3的时间变化特征及O3与其前体物体积分数的相关性，同时分析气温、相对湿度、风速、降水和日照时数等气象因素对O3体积分数的影响。结果表明：山西太原、大同、临汾3个城市的O3小时体积分数与日最大8 h平均体积分数都有超标情况发生，夏季O3污染以临汾最严重、大同相对最轻；一日内O3小时体积分数最大值出现在15:00左右，最小值出现在06:00左右，日变化呈单峰型分布，其中临汾O3小时体积分数的昼夜变化振幅最大、大同最小；各城市NOx、NO2、NO、CO等前体物体积分数均呈现白天低、夜间高的日变化过程，与O3日变化呈负相关；气温是影响夏季O3体积分数的最重要因素，其次为相对湿度，风速贡献最小，夏季O3体积分数高值多在高温低湿的午后，且太原、临汾O3体积分数受局地气象因素影响比大同显著。

关键词: O₃, 前体物, 气象因素, 变化特征