基于过程分析的京津冀区域典型城市臭氧成因

随着京津冀区域臭氧（O₃）污染问题日渐突出，探究和分析京津冀区域O₃变化特征和污染过程形成原因对区域大气污染防治工作具有重要意义.观测结果显示，春夏季京津冀区域较高的O₃浓度呈现南高北低的分布，北京、天津和石家庄这3座城市O₃高浓度往往伴随着偏南风的影响.基于WRF-Chem模式模拟和过程分析技术对2019年京津冀区域O₃变化特征和成因进行了深入分析，典型城市化学过程、垂直混合和输送的日变化有着鲜明的季节变化差异.其中在夏季午后化学过程是各城市O₃浓度增加的主要来源；垂直混合导致天津和石家庄O₃浓度增加，但使得北京O₃浓度减少；天津和石家庄存在净输出，而北京则为净流入.通过对比分析O₃污染和清洁过程结果表明，化学过程主导北京和石家庄污染过程午后O₃浓度增加，天津则为垂直混合，此外，北京和石家庄存在O₃净输入，天津则为净输出；而清洁过程中，垂直混合主...

Exploring Formation of Ozone in Typical Cities in Beijing-Tianjin-Hebei Region Using Process Analysis

As the problem of O₃ pollution in the Beijing-Tianjin-Hebei region becomes increasingly prominent, it is of great significance to explore and analyze the ozone variation characteristics and causes of the pollution process in the Beijing-Tianjin-Hebei region for regional air pollution prevention and control. The observations in this study showed that high O₃ concentration in spring and summer of the Beijing-Tianjin-Hebei region was higher in the south and lower in the north. The high O₃ concentration in Beijing, Tianjin, and Shijiazhuang was often accompanied by the influence of southern wind. Based on WRF-Chem model simulation and process analysis technology, the variation characteristics and causes of O₃ in The Beijing-Tianjin-Hebei region in 2019 were deeply analyzed. The diurnal variations in chemical processes, vertical mixing, and transportation in typical cities showed distinct seasonal variations. In summer afternoons, chemical processes were the main source of O₃ concentration increase in each city. Vertical mixing resulted in an increase in O₃ concentration in Tianjin and Shijiazhuang but a decrease in Beijing. Tianjin and Shijiazhuang had a net output, whereas Beijing had a net inflow. In the polluted O₃ process, the chemical process dominated the afternoon O₃ concentration increasing in Beijing and Shijiazhuang, whereas vertical mixing dominated in Tianjin. In addition, there was a net input of O₃ in Beijing and Shijiazhuang and a net output of O₃ in Tianjin. In the clean O₃ process, vertical mixing dominated the increase in O₃ concentration in Beijing and Shijiazhuang in the afternoon, whereas in Tianjin it was chemical processes. At the same time, the net output of O₃ existed in all three cities.