Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River Delta
Based on the meteorological, ozone (O<sub>3</sub>), and vertical observation data of 2020, this study sought to evaluate the daily variation in O<sub>3</sub>, particularly the characteristics of nocturnal ozone pollution. We also discuss the effect of local and mesoscale hori...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-08-01
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| Series: | Atmosphere |
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| Online Access: | https://www.mdpi.com/2073-4433/13/8/1318 |
| _version_ | 1797432510669389824 |
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| author | Honglong Yang Chao Lu Yuanyuan Hu Pak-Wai Chan Lei Li Li Zhang |
| author_facet | Honglong Yang Chao Lu Yuanyuan Hu Pak-Wai Chan Lei Li Li Zhang |
| author_sort | Honglong Yang |
| collection | DOAJ |
| description | Based on the meteorological, ozone (O<sub>3</sub>), and vertical observation data of 2020, this study sought to evaluate the daily variation in O<sub>3</sub>, particularly the characteristics of nocturnal ozone pollution. We also discuss the effect of local and mesoscale horizontal transport and vertical mixing on the formation of nocturnal O<sub>3</sub> pollution. Distinct seasonal characteristics of the daily O<sub>3</sub> variation in Shenzhen were identified. In particular, significant nocturnal peaks were found to regularly occur in the winter and spring (November–December and January–April). The monthly average of daily variation had a clear bimodal distribution. During the period, O<sub>3</sub> pollution frequently occurred at night, with the maximum hourly O<sub>3</sub> concentration reaching 203.5 μg/m<sup>3</sup>. Nocturnal O<sub>3</sub> pollution was closely associated with horizontal transport and vertical mixing. During the study period, the O<sub>3</sub> maximum values were recorded on 68 nights, primarily between 23:00 and 03:00, with occasional observation of two peaks. The impact of horizontal transport and vertical mixing on the nocturnal secondary O<sub>3</sub> maximum values was elaborated in two case studies, where vertical mixing was mainly associated with low-level jets, with strong wind shear enhancing turbulent mixing and transporting O<sub>3</sub> from the upper layers to the surface. |
| first_indexed | 2024-03-09T10:01:38Z |
| format | Article |
| id | doaj.art-868d47bb3dba4c15880360b369774a33 |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-03-09T10:01:38Z |
| publishDate | 2022-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-868d47bb3dba4c15880360b369774a332023-12-01T23:24:12ZengMDPI AGAtmosphere2073-44332022-08-01138131810.3390/atmos13081318Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River DeltaHonglong Yang0Chao Lu1Yuanyuan Hu2Pak-Wai Chan3Lei Li4Li Zhang5Shenzhen National Climate Observatory, Meteorological Bureau of Shenzhen Municipality, Shenzhen 518040, ChinaShenzhen National Climate Observatory, Meteorological Bureau of Shenzhen Municipality, Shenzhen 518040, ChinaShenzhen National Climate Observatory, Meteorological Bureau of Shenzhen Municipality, Shenzhen 518040, ChinaHong Kong Observatory, Hong Kong 999077, ChinaSchool of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, ChinaShenzhen National Climate Observatory, Meteorological Bureau of Shenzhen Municipality, Shenzhen 518040, ChinaBased on the meteorological, ozone (O<sub>3</sub>), and vertical observation data of 2020, this study sought to evaluate the daily variation in O<sub>3</sub>, particularly the characteristics of nocturnal ozone pollution. We also discuss the effect of local and mesoscale horizontal transport and vertical mixing on the formation of nocturnal O<sub>3</sub> pollution. Distinct seasonal characteristics of the daily O<sub>3</sub> variation in Shenzhen were identified. In particular, significant nocturnal peaks were found to regularly occur in the winter and spring (November–December and January–April). The monthly average of daily variation had a clear bimodal distribution. During the period, O<sub>3</sub> pollution frequently occurred at night, with the maximum hourly O<sub>3</sub> concentration reaching 203.5 μg/m<sup>3</sup>. Nocturnal O<sub>3</sub> pollution was closely associated with horizontal transport and vertical mixing. During the study period, the O<sub>3</sub> maximum values were recorded on 68 nights, primarily between 23:00 and 03:00, with occasional observation of two peaks. The impact of horizontal transport and vertical mixing on the nocturnal secondary O<sub>3</sub> maximum values was elaborated in two case studies, where vertical mixing was mainly associated with low-level jets, with strong wind shear enhancing turbulent mixing and transporting O<sub>3</sub> from the upper layers to the surface.https://www.mdpi.com/2073-4433/13/8/1318secondary ozone maximumadvectionvertical mixing |
| spellingShingle | Honglong Yang Chao Lu Yuanyuan Hu Pak-Wai Chan Lei Li Li Zhang Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River Delta Atmosphere secondary ozone maximum advection vertical mixing |
| title | Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River Delta |
| title_full | Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River Delta |
| title_fullStr | Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River Delta |
| title_full_unstemmed | Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River Delta |
| title_short | Effects of Horizontal Transport and Vertical Mixing on Nocturnal Ozone Pollution in the Pearl River Delta |
| title_sort | effects of horizontal transport and vertical mixing on nocturnal ozone pollution in the pearl river delta |
| topic | secondary ozone maximum advection vertical mixing |
| url | https://www.mdpi.com/2073-4433/13/8/1318 |
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