Abstract: Based on the hourly and daily NO₂, CO and O₃ mass concentration data from environment monitoring station and daily meteorological observation data from weather station in Shijiazhuang of Hebei Province from March 2016 to February 2018, the temporal distribution characteristics of ozone mass concentration near surface and their relationships of it with weather factors and its precursors (NO₂、CO) were analyzed. The results show that the situation of O₃ pollution in Shijiazhuang in 2017 was more serious than that in 2016. The super-standard days of ozone mass concentration in 2017 was 30 days more than that in 2016, and the super-standard rate and annual average mass concentration of ozone increased 8% and 17 μg·m^-3, respectively. The seasonal variation of ozone mass concentration was obvious in Shijiazhuang, and it successively decreased in summer, spring, autumn and winter. The daily average ozone mass concentration was relatively high from May to September and exceeded 160 μg·m^-3, and reached the peak (208 μg·m^-3) in June. The daily variation of ozone mass concentration showed a single peak distribution, and the minimum appeared at 07:00 and the maximum appeared from 14:00 to 16:00. The ozone mass concentration was likely to exceed the standard under strong radiation, high temperature, long sunshine hours, good visibility, non-precipitation and lower relative humidity weather conditions. The O₃ mass concentration had a significantly positive correlation with NO₂ and CO mass concentration in summer and significantly negative correlation in winter.

Key words: ozone near surface, temporal change characteristics, weather conditions

摘要： 利用2016年3月至2018年2月河北石家庄市环境监测站O₃及其前体物质量浓度逐时和逐日观测资料，以及气象站逐日气象观测数据，分析石家庄市近地层O₃质量浓度的时间变化特征及其与前体物NO₂、CO和气象条件的关系。结果表明：石家庄市O₃污染2017年比2016年严重，2017年比2016年O₃超标日数增加30 d，超标率上升8%，O3年平均质量浓度上升17 μg·m^-3。O₃质量浓度具有明显的季节变化特征，自夏季、春季、秋季、冬季依次降低，5—9月O₃质量浓度较高，平均值超过160 μg·m^-3，6月达到峰值208 μg·m^-3。O₃质量浓度的日变化表现为单峰型分布，最低值出现在07:00左右，峰值在14:00—16:00。太阳辐射强、气温高、日照时数长、能见度好、无降水和相对湿度较低的条件下，石家庄市易出现O₃浓度超标天气。前体物NO₂、CO与O₃质量浓度之间夏季呈现显著正相关，而冬季则呈显著负相关。

关键词: 近地层O₃, 时间变化特征, 气象条件