基于CAMx-OSAT方法的西宁臭氧来源解析

利用青海省西宁市2018-2019年O3浓度高值时期监测数据,结合CAMx-OSAT方法从控制型、分类排放源、区域贡献3个方面定量剖析西宁的O3污染来源.结果表明:西宁O3浓度整体为VOCs控制,主城四区(城东区、城西区、城北区、城中区)尤其突出,且夏季较为显著;2018年和2019年VOCs的贡献占比分别为9.76％...

Source apportionment of ozone in Xining using CAMx-OSAT method

The contribution of Xining ozone (O₃) pollution sources from three aspects, i.e., O₃ control types, source categories and source regions, was quantitatively analyzed by using a comprehensive air quality model with extensions and O₃ source apportionment technology (CAMx-OSAT). This model is driven by the monitoring data of high ozone value period in Xining, Qinghai Province from 2018 to 2019. The results indicated that the O₃ concentration in Xining was mainly controlled by volatile organic compounds (VOCs), especially in the main urban area, and was more significantly in summer. The contribution of VOCs in 2018 and 2019 was 9.76% and 8.91%, respectively. In the surrounding areas, O₃ was jointly controlled by nitrogen oxide (NO_x) and VOCs. In addition to the background, industrial sources contributed the most to the generation of Xining O₃, accounting for 52.22% and 47.24% in 2018 and 2019 respectively, followed by transportation sources. During the simulation period, O₃ in Xining was mainly generated locally, with the contribution ratio of local sources to external transmission to be about 2:1. The four main urban areas were the main local source regions of O₃ generation, accounting for about 32.26% (excluding the background field). On the other hand, Haidong was the main contribution area for external transmission. In summary, controlling the emissions of VOCs from industry and transportation in the main urban area would be effective for reducing O₃ pollution in Xining during the summer daytime.