欧洲城市中超细颗粒的年间趋势
Meritxell Garcia-Marlès1, Rosa Lara2, Cristina Reche2
1Institute of Environmental Assessment and Water Research (IDAEA-CSIC), 08034 Barcelona, Spain; Department of Applied Physics-Meteorology, University of Barcelona, Barcelona, 08028, Spain.
Environment international
|March 9, 2024
概括
长期空气质量监测显示,超细颗粒 (UFP) 在更大尺寸模式下下降,这可能是由于车辆排放标准. 然而,较小的核化模式粒子仍然是一个问题,可能受到城市变暖的影响.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 公共卫生 公共卫生
背景情况:
- 超细颗粒 (UFP,≤100nm) 由于深呼吸道透和全身转移,造成健康风险.
- 评估UFP度的长期趋势对于了解空气质量改善和持续挑战至关重要.
研究的目的:
- 评估欧洲和美国各种城市环境中超细粒子数量大小分布 (PNSD) 的长期 (5-11年) 趋势.
- 调查其他污染物,气象变量和排放控制策略对UFP趋势的影响.
主要方法:
- 分析了来自12个城市背景,5个交通,3个郊区背景和1个区域背景站点的PNSD数据.
- 应用非参数的Theil-Sen方法来检测趋势和进行总体和环境特异性趋势评估的元分析.
- 评估共同污染物度 (NO,NO2,BC,CO) 和气象数据.
主要成果:
- 在Aitken (25-100 nm) 和积累 (100-800 nm) 模式中观察到NO,NO2,BC,CO和颗粒的显著下降趋势.
- 欧元5/V和6/VI车辆标准和柴油颗粒过器 (DPF) 对减少较大的颗粒排放的积极影响.
- 相反的趋势和核化模式粒子 (<25 nm) 的控制不足,不受DPF的影响,并可能受到城市变暖的影响.
结论:
- 车辆排放标准和DPF通过减少较大的UFP模式改善了空气质量.
- 核化模式颗粒仍然是一个重大的挑战,因为DPF的有效性不完整,以及潜在的非交通来源.
- 城市温度的增加也可能影响核和Aitken模式粒子度.
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