Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, China
Emerging research indicates that ground-level ozone (O<sub>3</sub>) has become a leading contributor to air quality concerns in many Chinese cities, with the Yangtze River Delta (YRD) region facing particular challenges. This study investigated the characterization of air pollutants in W...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-03-01
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| Series: | Atmosphere |
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| Online Access: | https://www.mdpi.com/2073-4433/15/3/382 |
| _version_ | 1797242069307097088 |
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| author | Yezheng Wu Jun Gu Xurong Shi Wenyuan Shen Hao Zhang Xin Zhang |
| author_facet | Yezheng Wu Jun Gu Xurong Shi Wenyuan Shen Hao Zhang Xin Zhang |
| author_sort | Yezheng Wu |
| collection | DOAJ |
| description | Emerging research indicates that ground-level ozone (O<sub>3</sub>) has become a leading contributor to air quality concerns in many Chinese cities, with the Yangtze River Delta (YRD) region facing particular challenges. This study investigated the characterization of air pollutants in Wujiang, which is located within the YRD demonstration zone, during the warm season (April–September) of 2022. The contributions of emission and meteorology to O<sub>3</sub> were identified, the O<sub>3</sub>-NO<sub>X</sub>-VOC sensitivities were discussed, and the VOC sources and their contributions to O<sub>3</sub> formation were analyzed. A random forest model revealed that the high O<sub>3</sub> concentration was mainly caused by a combination of increased emission intensity due to the resumption of work and production after the COVID-19 pandemic, along with adverse meteorological conditions. The results revealed more than 92% of the pollution days were related to O<sub>3</sub> during the warm season, and the impact of O<sub>3</sub> precursor emissions was slightly greater than that of the meteorological conditions. O<sub>3</sub> formation was in the VOC-limited regime, and emission reduction strategies targeting VOCs, particularly aromatics such as toluene and xylene, have been identified as the most effective approach for mitigating O<sub>3</sub> pollution. Changes in O<sub>3</sub>-NO<sub>X</sub>-VOC sensitivity were also observed from the VOC-limited regime to the transitional regime, which was primarily driven by variations in the NO<sub>X</sub> concentrations. The VOC source analysis results showed that the contributions of gasoline vehicle exhaust and diesel engine exhaust (mobile source emissions) were significantly greater than those of the other sources, accounting for 20.8% and 16.5% of the total VOC emissions, respectively. This study highlights the crucial role of mobile source emission control in mitigating O<sub>3</sub> pollution. Furthermore, prioritizing the control of VOC emission sources with minimal NO<sub>X</sub> contributions is highly recommended within the VOC-limited regime. |
| first_indexed | 2024-04-24T18:33:21Z |
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| id | doaj.art-5eb34931774d4013a70398b49c275006 |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-04-24T18:33:21Z |
| publishDate | 2024-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-5eb34931774d4013a70398b49c2750062024-03-27T13:20:52ZengMDPI AGAtmosphere2073-44332024-03-0115338210.3390/atmos15030382Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, ChinaYezheng Wu0Jun Gu1Xurong Shi2Wenyuan Shen3Hao Zhang4Xin Zhang5Suzhou Environmental Monitoring Station, Suzhou 215000, ChinaJiangsu Suzhou Environmental Monitoring Centre, Suzhou 215004, ChinaInstitute of Atmospheric Environment, Chinese Academy of Environmental Planning, Beijing 100041, ChinaSuzhou Environmental Monitoring Station, Suzhou 215000, ChinaSchool of Public Health, Shandong Second Medical University, Weifang 261053, ChinaInstitute of Atmospheric Environment, Chinese Academy of Environmental Planning, Beijing 100041, ChinaEmerging research indicates that ground-level ozone (O<sub>3</sub>) has become a leading contributor to air quality concerns in many Chinese cities, with the Yangtze River Delta (YRD) region facing particular challenges. This study investigated the characterization of air pollutants in Wujiang, which is located within the YRD demonstration zone, during the warm season (April–September) of 2022. The contributions of emission and meteorology to O<sub>3</sub> were identified, the O<sub>3</sub>-NO<sub>X</sub>-VOC sensitivities were discussed, and the VOC sources and their contributions to O<sub>3</sub> formation were analyzed. A random forest model revealed that the high O<sub>3</sub> concentration was mainly caused by a combination of increased emission intensity due to the resumption of work and production after the COVID-19 pandemic, along with adverse meteorological conditions. The results revealed more than 92% of the pollution days were related to O<sub>3</sub> during the warm season, and the impact of O<sub>3</sub> precursor emissions was slightly greater than that of the meteorological conditions. O<sub>3</sub> formation was in the VOC-limited regime, and emission reduction strategies targeting VOCs, particularly aromatics such as toluene and xylene, have been identified as the most effective approach for mitigating O<sub>3</sub> pollution. Changes in O<sub>3</sub>-NO<sub>X</sub>-VOC sensitivity were also observed from the VOC-limited regime to the transitional regime, which was primarily driven by variations in the NO<sub>X</sub> concentrations. The VOC source analysis results showed that the contributions of gasoline vehicle exhaust and diesel engine exhaust (mobile source emissions) were significantly greater than those of the other sources, accounting for 20.8% and 16.5% of the total VOC emissions, respectively. This study highlights the crucial role of mobile source emission control in mitigating O<sub>3</sub> pollution. Furthermore, prioritizing the control of VOC emission sources with minimal NO<sub>X</sub> contributions is highly recommended within the VOC-limited regime.https://www.mdpi.com/2073-4433/15/3/382ozonerandom forestO<sub>3</sub>-NO<sub>X</sub>-VOC sensitivitysource apportionmentobservation-based model (OBM)demonstration area |
| spellingShingle | Yezheng Wu Jun Gu Xurong Shi Wenyuan Shen Hao Zhang Xin Zhang Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, China Atmosphere ozone random forest O<sub>3</sub>-NO<sub>X</sub>-VOC sensitivity source apportionment observation-based model (OBM) demonstration area |
| title | Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, China |
| title_full | Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, China |
| title_fullStr | Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, China |
| title_full_unstemmed | Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, China |
| title_short | Characteristics and Formation Mechanism of Ozone Pollution in Demonstration Zone of the Yangtze River Delta, China |
| title_sort | characteristics and formation mechanism of ozone pollution in demonstration zone of the yangtze river delta china |
| topic | ozone random forest O<sub>3</sub>-NO<sub>X</sub>-VOC sensitivity source apportionment observation-based model (OBM) demonstration area |
| url | https://www.mdpi.com/2073-4433/15/3/382 |
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