在美国大陆,野火对O3的影响使用PM2.5和通用添加模型 (2018-2023)
Haebum Lee1, Daniel A Jaffe1,2
1School of Science, Technology, Engineering, and Mathematics, University of Washington, Bothell, Washington 98011, United States.
Environmental science & technology
|August 9, 2024
概括
野火烟雾严重影响美国空气质量,增加细颗粒物 (PM2.5) 和臭氧 (O3) 水平. 烟雾影响的天数占PM2.5的大部分超值和臭氧超值的很大一部分,突出火灾.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 空气质量监测 空气质量监测
背景情况:
- 野火烟雾,特别是来自大型事件的烟雾,正在越来越多地影响美国各地的空气质量.
- 以前的研究表明烟雾对空气污染物的影响,但量化其对健康标准超标的贡献至关重要.
研究的目的:
- 量化野火烟雾对每日细颗粒物度 (PM2.5) 和最大每日8小时平均值 (MDA8) 臭氧 (O3) 的影响.
- 确定烟雾对超过PM2.5和O3.3的国家卫生空气质量标准的日数的贡献.
主要方法:
- 来自约600个美国空气监测站 (2018-2023) 的PM2.5和卫星烟雾数据的分析.
- 统计建模 (通用添加模型) 用于使用无烟日数据作为基线,估计烟雾影响天的臭氧贡献.
- 计算烟雾对PM2.5和O3超值日的百分比贡献.
主要成果:
- 在2018-2023年5月至9月期间,烟雾存在于14%的日期,在2020年,2021年和2023年有显著的增加.
- 受到烟雾影响的日子显示平均PM2.5 (11μg m-3) 和MDA8 O3 (8ppb) 度较高.
- 烟雾占PM2.5超值天的94%,O3超值天的36%,烟雾日估计的平均O3贡献为7.8±6.0ppb.
- 在研究期间,野火烟雾占美国所有超标日数的25%,在2023年增加到38%.
结论:
- 野火烟雾是美国空气质量标准超出PM2.5和O3的重要驱动因素.
- 烟雾对空气质量的频率和影响需要在空气质量管理和健康影响评估中考虑.
- 未来的空气质量预测和政策决策必须考虑到野火事件日益增长的影响.
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