2019年中国城市大气臭氧污染时空格局及其影响因素研究

Spatial and temporal patterns of ozone pollution and its influencing factors in China in 2019

基于2019年中国338个城市的1 836个监测站逐小时臭氧监测数据,本研究探讨了不同气候区臭氧质量浓度变化的时空特征,揭示了不同气候区自然因素和社会因素对臭氧污染的相对贡献及其关键影响因子。结果表明:中国城市大气臭氧质量浓度年评价值介于84~193μg/m^(3),年平均质量浓度为141μg/m^(3),城市空气质量良好,但全国仍有22%的城市臭氧年评价值超标,超标天数约占全年的6%。城市臭氧污染具有较强的空间异质性,温带季风气候区城市臭氧污染最为严重,超标城市高达44%,平均超标天数约占全年的10%,臭氧质量浓度等级为轻度污染(济南、淄博和滨州);温带大陆性气候区臭氧浓度等级为优,超标天数仅占全年的1%。城市臭氧质量浓度具有较强的季节特征,总体上春夏高于秋冬,夏季臭氧平均质量浓度最高(109μg/m^(3))、春(108μg/m^(3))、秋(86μg/m^(3))次之,而冬季(67μg/m^(3))最低。冗余分析表明,社会因素(PM_(2.5)和GDP等)是影响城市臭氧质量浓度升高或降低的主导因素,自然因素起辅助作用。不同气候区,自然和社会因素对臭氧的影响具有明显的差异性。本研究可为中国城市有效应对臭氧污染、建设宜居城市提供重要理论支撑。

Based on hourly ozone monitoring data from 1836 monitoring stations in 338 cities in China,this study investigates the spatial and temporal characteristics of ozone concentration variation in different climatic zones,and reveals the relative contributions of natural and social factors to ozone pollution in different climatic zones and their key influencing factors.The results show that the annual evaluated values of ozone concentration in Chinese cities range from 84 to 193μg/m^(3),with an annual average concentration of 141μg/m^(3)and good urban air quality.However,22%of the cities in China still exceeded the annual ozone assessment value,accounting for about 6%of the total number of days in the year.Urban ozone pollution has a strong spatial heterogeneity,temperate climate zone urban ozone pollution is the most serious,exceeds the standard city up to 44%,the average number of days exceeded about 10%of the year,ozone concentration level is light pollution,(Jinan,Zibo and Binzhou,etc.);The ozone concentration standard in the arid and semi-arid climate zone was excellent,with only 1%of the days of the year exceeding the standard.Urban ozone concentrations have strong seasonal characteristics,generally higher in spring and summer than in autumn and winter.Average ozone concentrations are highest in summer(109μg/m^(3)),followed by spring(108μg/m^(3))and autumn(86μg/m^(3)),and lowest in winter(67μg/m^(3)).Redundancy analysis shows that social factors(PM.s and GDP etc.)are the main factors influencing the increase or decrease of urban ozone concentrations,with natural factors playing a secondary role.There is significant variability in the influence of natural and social factors on ozone in different climatic zones.This study can provide important theoretical support for cities in China to effectively cope with ozone pollution and build livable cities.