{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T11:19:34Z","timestamp":1778066374921,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,27]],"date-time":"2025-01-27T00:00:00Z","timestamp":1737936000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2022YFC3703502"],"award-info":[{"award-number":["2022YFC3703502"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2023YFC3709302"],"award-info":[{"award-number":["2023YFC3709302"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["42307133"],"award-info":[{"award-number":["42307133"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Natural Science Foundation of China","award":["2022YFC3703502"],"award-info":[{"award-number":["2022YFC3703502"]}]},{"name":"National Natural Science Foundation of China","award":["2023YFC3709302"],"award-info":[{"award-number":["2023YFC3709302"]}]},{"name":"National Natural Science Foundation of China","award":["42307133"],"award-info":[{"award-number":["42307133"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxics"],"abstract":"<jats:p>Ozone pollution in Hangzhou Bay, one of the seven petrochemical clusters in China, is severe. Early ozone pollution has been detected recently, such as the maximum daily 8 h average (MDA8) ozone concentration in Jiaxing achieving 171.0 \u03bcg\/m3 on 7 March 2023. Satellites have observed tropospheric column concentrations of ozone precursors formaldehyde (HCHO) and nitrogen dioxide (NOx), and quantitative models are proposed to reveal the causes of the early onset of ozone pollution. VOC-limited and transitional regimes dominate most areas in Hangzhou Bay, and NOx-limited regimes dominate the region around Hangzhou Bay, such as northeastern Jiangsu Province. Results show that HCHO column concentrations are increasing in VOC-limited regions, and NOx column concentrations are increasing more rapidly than HCHO in NOx-limited regions. According to multivariate linear regression (MLR), early spring ozone pollution in Hangzhou Bay is mainly caused by meteorological drivers. Hangzhou Bay has formed an atmospheric meteorological environment with high temperature and low humidity. The richer solar radiation intensifies the photochemical reactions associated with tropospheric ozone formation, producing more tropospheric ozone. Based on the Shapley Additive Explanation (SHAP) algorithm, ozone pollution increases when solar radiation exceeds 12 million J\/m2 and is accompanied by high temperatures. Overall, reducing VOC emissions helps to mitigate ozone growth in Shanghai and northern Hangzhou Bay, while reducing NOx emissions is more effective in northeastern Jiangsu Province.<\/jats:p>","DOI":"10.3390\/toxics13020099","type":"journal-article","created":{"date-parts":[[2025,1,28]],"date-time":"2025-01-28T08:57:48Z","timestamp":1738054668000},"page":"99","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Investigation of the Earliest Ozone Pollution Events in Hangzhou Bay, China Based on Observations and ERA5 Reanalysis Data"],"prefix":"10.3390","volume":"13","author":[{"given":"Tianen","family":"Yao","sequence":"first","affiliation":[{"name":"Department of Global Health, School of Public Health, Peking University, Beijing 100191, China"},{"name":"Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-3118-2467","authenticated-orcid":false,"given":"Xinhao","family":"Li","sequence":"additional","affiliation":[{"name":"Georgia Institute of Technology, School of Earth and Atmospheric Sciences, Atlanta, GA 30332, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhi","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China"},{"name":"Dongsheng District Meteorological Service, Ordos 017099, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinyu","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Global Health, School of Public Health, Peking University, Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-5708-2602","authenticated-orcid":false,"given":"Jinjia","family":"Zhang","sequence":"additional","affiliation":[{"name":"National School of Development, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yaqi","family":"Wang","sequence":"additional","affiliation":[{"name":"Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianhui","family":"Guo","sequence":"additional","affiliation":[{"name":"Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7682-4311","authenticated-orcid":false,"given":"Jing","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11423","DOI":"10.5194\/acp-20-11423-2020","article-title":"Increases in surface ozone pollution in China from 2013 to 2019: Anthropogenic and meteorological influences","volume":"20","author":"Li","year":"2020","journal-title":"Atmos. 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