韩国和中国的乙醇和甲醇:目前库存中缺少大量人为排放的证据
Ellie Beaudry1, Daniel J Jacob1,2, Kelvin H Bates3
1Harvard University, John A. Paulson School of Engineering and Applied Sciences, Cambridge, Massachusetts 02138, United States.
ACS ES&T air
|April 17, 2025
概括
韩国和中国城市空气中乙醇和甲醇的高含量表明,挥发性化学产品 (VCP) 的排放在当前模型中并未完全考虑. 这些VCP也导致了表面臭氧的增加.
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:
- 在2015-2017年实地活动期间,在韩国和中国的城市空气中观察到乙醇和甲醇的度升高.
- 当前的排放清单不充分反映了这些观察到的水平,表明了解城市空气污染源存在差距.
研究的目的:
- 调查韩国和中国城市大气中高乙醇和甲醇度的来源.
- 量化挥发性化学品 (VCP) 排放对空气质量和臭氧形成的影响.
主要方法:
- 利用了来自KORUS-AQ,MAPS-首尔和APHH-北京现场活动的数据.
- 使用GEOS-Chem大气模型来模拟观察到的度和测试排放场景.
- 分析了乙醇和甲醇之间的相关性,以推断排放特征.
主要成果:
- GEOS-Chem模拟无法复制观察到的乙醇和甲醇水平,而不会引发显著的VCP排放.
- 据估计,与美国相比,韩国和中国的人均VCP排放量在韩国和中国明显高于美国.
- 强烈的乙醇-甲醇相关性表明VCP中含有显著的甲醇成分,与美国不同.
- 将VCP排放纳入模型,使模拟表面臭氧在研究区域中增加了1-3ppb.
- 观察到 3.2 ppb 的高自由热层甲醇背景,可能是生物圈的,但没有被 GEOS-Chem 复制.
结论:
- 挥发性化学产品是东亚城市空气中乙醇和甲醇的重要,未被考虑的来源.
- 这些VCP排放导致该地区表面臭氧水平升高.
- 需要进一步的研究来准确地建模生物圈甲醇贡献,并完善VCP排放清单.
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