Abstract：
The synergistic responses of O3 and PM2.5 to their common precursors remain unclear within industrial cities with complex emissions. In this study, hundreds of scenarios of jointly reduced local NOx and VOCs emissions were designed along with the source apportionment techniques embedded in the Comprehensive Air quality Model with extensions (CAMx) system to explore the locally formed O3 and PM2.5 sensitivities to the reduced emissions of NOx and VOCs. The results indicate that locally formed O3 and PM2.5 are more connected to local emissions, resulting in unique formation sensitivities. Local O3 formation is usually in a transitional regime and transferred to VOC-limited condition under O3-polluted conditions due to high VOC emissions. Locally formed O3 and PM2.5 vary largely in different functional regions due to different emission feature and meteorological condition. When reducing VOCs emissions alone, an increase in PM2.5 formation could be observed due to the increase in the formation of nitrate resulting from reduced competition of NOx in O3 formation. To reduce PM2.5 and O3 concentrations simultaneously, specific ratios of NOx reduction percentage to VOC reduction percentage should be considered to different functional regions under different pollution levels. This research highlights the importance to conduct targeted sensitivity tests for emission reduction in different functional zones with complex emission features for the coordinated control of O3 and PM2.5 pollution in typical industrialized cities.
摘要：
在排放复杂的工业城市中，O3和PM2.5对其常见前体的协同反应尚不清楚。在这项研究中,设计了数百种联合减少局部NOx和VOCs排放的方案，以及嵌入在具有扩展功能的综合空气质量模型（CAMx）系统中的源分配技术，以探索局部形成的O3和PM2.5对NOx和VOCs排放减少的敏感性。结果表明，局部形成的O3和PM2.5与局部排放的联系更大，导致独特的地层敏感性。局部O3的形成通常处于过渡状态，并由于高VOC排放而在O3污染条件下转移到VOC限制条件。由于不同的排放特征和气象条件，局部形成的O3和PM2.5在不同的功能区差异很大。单独减少VOCs排放时，由于O3形成中NOx的竞争减少导致硝酸盐的形成增加，因此可以观察到PM2.5的形成增加。同时降低PM2.5和O3浓度，在不同的污染水平下，应考虑不同功能区的NOx还原百分比与VOC还原百分比的特定比率。这项研究强调了在具有复杂排放特征的不同功能区进行有针对性的减排敏感性测试的重要性，以协调控制典型工业化城市的O3和PM2.5污染。
