中国环境科学

作者：王庆, 邓涛, 吴兑, 何国文, 张雪, 欧阳珊珊, 陶丽萍, 张泽彪, 吴晟, 周振

单位：1. 暨南大学, 质谱仪器与大气环境研究所, 广东省大气污染在线源解析系统工程技术研究中心, 广东 广州 510632;2. 中国气象局广州热带海洋气象研究所, 广东省区域数值天气预报重点实验室, 广东 广州 510640;3. 中山大学大气科学学院, 广东 珠海 519082;4. 暨南大学环境与气候研究院, 广东 广州 511443

关键词：粤港澳大湾区,气溶胶,臭氧,垂直分布,复合污染

基金：国家重点研发计划项目(2023YFC3709201);国家自然科学基金资助项目(42275123);广东省重点领域研发计划项目(2020B1111360003);广东省基础与应用基础研究基金资助项目(2023A1515012448,2023A1515012205);广东省社会发展科技协同创新项目(2024A1111120022);中国气象局重点创新团队项目(CMA2023ZD08);广东省气象局科技创新团队计划项目(GRMCTD202003)

In recent years, the concentration of particulate matter in the Guangdong-Hong Kong-Macao Greater Bay Area has decreased significantly, but O3 pollution has continued to increase under the background of anthropogenic emission reduction. In this study, multi-source observation data of ground-based, tower-based, ozonesonde, aircraft (IAGOS), and satellites in the Greater Bay Area from 2006 to 2020 were used to analyze the three-dimensional spatial and temporal variation characteristics of aerosols, O3 and related meteorological conditions, with special attention to the vertical distribution characteristics of aerosol and O3, and the influence of the lower part of boundary layer aerosols on O3 concentration. The results showed that the concentrations of surface PM10decreased (-2.2μg/(m3ža)) from 2006 to 2020, while the concentrations of surface O3 and boundary layer O3 increased (+0.8μg/(m3ža), +0.6μg/(m3ža)). Surface PM2.5 decreased (-1.5μg/(m3ža)) since 2014. There were differences and commonalities between vertical aerosol and O3 distribution. The vertical extinction coefficient of aerosol (within 1000m) decreased with increasing height (average rate of change -0.06km-1/hm), while the O3 concentration increased with increasing height (average rate of change +1.4μg/(m3žhm)). Generally, both vertical aerosol and O3 reached their lowest values in summer and both reached their highest concentrations in the free troposphere in spring. Since 2006, the average surface temperature increased by 0.05℃/a, the average relative humidity increased by 0.44%/a, and the average wind speed decreased by 0.02m/(s×a), which to a certain extent can explain the simultaneous increase/decrease of aerosol and O3 concentrations in a given year. In summer, under the influence of the South China Sea monsoon, the relative humidity within the boundary layer was high, while in fall the temperature within the boundary layer was higher and the humidity was moderate, and this kind of meteorological conditions were more favorable for photochemical reactions. Based on the four years of observation of O3 and PM10 at Canton Tower, the high surface PM10 value appeared at night, and the high PM10value of 454m appeared in the afternoon and was strongly positively correlated with the O3 concentration at 454m, which indicates that the secondary reaction of aerosols in the boundary layer in the late afternoon, as well as the backscattering of photochemical radiation by these secondary aerosols, may be one of the factors that exacerbate the O3 pollution in the boundary layer. The results of the study will help deepen the understanding of the vertical distribution of aerosols and O3 and the characteristics of the complex pollution in the Greater Bay Area.

来源：2024年第11期

《中国环境科学》期刊编辑部

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