在2020年春季封锁期间,大气氧化能力在中国成都上升:未来二次污染控制的教训
Zhaofeng Tan1, Miao Feng2, Hefan Liu2
1State Key Joint Laboratory of Environmental Simulation and Pollution Control (Peking University), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
Environmental science & technology
|May 11, 2024
概括
在COVID-19封锁期间,成都的空气质量因减少的氧化 (NOx) 而有所改善. 然而,高的臭氧和不变的基含量表明需要控制基排放以减轻二次污染.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 空气质量研究 空气质量研究
背景情况:
- 随着COVID-19大流行,人们开始实施封锁,这大大改变了人类活动和排放.
- 了解减少排放对大气化学的影响对于空气质量管理至关重要.
- 之前关于减排影响的研究通常基于模型,缺乏真实世界的观测数据.
研究的目的:
- 在成都封锁期间 (2020年1月至3月) 测量光化学前体.
- 评估减少排放对大气氧化能力的影响.
- 为了确定影响封锁期间二次污染形成的关键因素.
主要方法:
- 在封锁期间收集了光化学前体的观测数据.
- 将封锁数据与前两年同等时期的数据进行比较.
- 利用基于观察的模型来模拟大气氧化能力和激素度.
主要成果:
- 模拟的基 (OH),基 (HO2) 和过氧基 (RO2) 度分别增加了42%,220%和277%.
- 根本的转换率 (OH氧化率和臭氧生产率) 分别增加了24%和48%.
- 氧化能力略有增加,受基度不变和臭氧升高的影响.
结论:
- 封锁期间减少的氧化 (NOx) 导致激素度显著增加.
- 由于臭氧升高,基臭氧分解成为一个重要的基因来源.
- 控制烯排放对于减轻成都和潜在的中国其他地区的二次污染至关重要,未来可以减少氧化物.
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