在北京夏季三年行动计划之后,二次气溶的显著减少
Yan Li1,2, Lu Lei1,2, Jiaxing Sun1,2
1State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
Environmental science & technology
|October 12, 2023
概括
北京 北京 北京 北京 北京
科学领域:
- 大气化学 大气化学
- 空气质量研究 空气质量研究
背景情况:
- 在"三年行动计划" (2018-2020年) 期间,中国的空气质量有所改善.
- 北京的夏季气溶成分和来源仍然不太清楚.
- 了解这些变化对于有针对性的空气污染控制战略至关重要.
研究的目的:
- 描述北京夏季气溶成分,特性和来源的变化.
- 研究气象学和减排在这些变化中的作用.
- 为在不断变化的环境条件下提供有关气溶化学演变的见解.
主要方法:
- 在5个夏季 (2018-2022) 实时测量气溶成分.
- 社区多尺度空气质量 (CMAQ) 模型模拟.
- 对气象数据和气体前体的分析.
主要成果:
- 观察到二次无机气溶和二次有机气溶 (SOA) 的显著减少 (55-67%).
- 主要的气溶物种和气态前体显示较小的下降.
- 大气氧化能力的降低和气溶液体水的减少影响了SOA和酸盐的形成.
- 气象学影响了酸盐和生物 SOA,而排放控制减少了硫酸盐,初级有机气溶和人为 SOA.
结论:
- 在三年行动计划期间,排放控制在减少主要气溶成分方面起到了决定性的作用.
- 气象因素对酸盐和生物 SOA 等特定气溶类型产生了重大影响.
- 气溶成分的变化与排放减少和气象转变,特别是相对湿度,都密切相关.
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