Wang Yuchen, Wang Ming, Ding Feng, Chen Xueqi, Zhang Liangyu
Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China.
Jiangsu Nanjing Environmental Monitoring Center, Nanjing 210041, China.
Toxics. 2025 Aug 9;13(8):670. doi: 10.3390/toxics13080670.
Surface ozone (O), a key hurdle in air quality improvement in China, often displays regional pollution characteristics. This study investigated the influence of meteorological conditions and air mass transport on O and non-methane hydrocarbons (NMHCs) concentrations in Nanjing, located in the western Yangtze River Delta (YRD) region of China during April-September of 2020 and 2021 based on online observations of O and its precursors and meteorological conditions, backward-trajectory analysis, and an observation-based box model (OBM). O concentrations rose with temperature, albeit non-linearly. Southeastern trajectories constituted the most dominant air mass transport pathway (29.3%) and were associated with the highest O concentrations. The concentration-weighted trajectory analyses of O and NMHCs during four O pollution episodes suggested that urban/industrial areas in central and eastern YRD were potential source regions. The OBM results indicated that while O sensitivity was dominated by the NMHCs-limited regime, the relative contributions of three O sensitivity regimes varied across air mass trajectory clusters. The southeastern air masses with long-range transport showed the highest frequency of the transition and NO-limited O sensitivity regimes. These findings underscore the crucial role of regional air mass transport not only in determining O and NMHCs concentrations but also in shaping O formation sensitivity, highlighting the necessity of implementing regionally coordinated control strategies for effective O and NMHCs pollution mitigation.
地表臭氧（O₃）是中国空气质量改善的一个关键障碍，常呈现区域污染特征。本研究基于对O₃及其前体物和气象条件的在线观测、后向轨迹分析以及基于观测的箱式模型（OBM），调查了2020年4月至9月以及2021年4月至9月期间气象条件和空气质量传输对位于中国长江三角洲（YRD）地区西部的南京O₃和非甲烷碳氢化合物（NMHCs）浓度的影响。O₃浓度随温度升高，尽管是非线性的。东南方向的轨迹构成了最主要的空气质量传输路径（29.3%），且与最高的O₃浓度相关。在四次O₃污染事件期间对O₃和NMHCs进行的浓度加权轨迹分析表明，长三角地区中部和东部的城市/工业区是潜在的源区。OBM结果表明，虽然O₃敏感性主要由NMHCs限制型主导，但三种O₃敏感性类型的相对贡献在不同空气质量轨迹簇中有所不同。具有长距离传输的东南方向气团显示出转变型和NO限制型O₃敏感性的最高频率。这些发现强调了区域空气质量传输不仅在决定O₃和NMHCs浓度方面，而且在塑造O₃形成敏感性方面的关键作用，突出了实施区域协调控制策略以有效减轻O₃和NMHCs污染的必要性。
