来自美国移动来源的有机反应碳空气排放
Benjamin N Murphy1, Darrell Sonntag2, Karl M Seltzer3
1Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, United States.
概括
在美国,移动源对大气中的活性有机碳 (ROC) 和有机气溶 (OA) 产生重大影响. 更新的排放因子提高了细颗粒有机碳空气质量模型的准确性.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 空气质量建模空气质量模型
背景情况:
- 移动来源是大气中的活性有机碳 (ROC) 的主要贡献者,特别是在美国的城市地区.
- 目前用于量化移动源排放的方法缺乏详细的挥发性和有机气溶 (OA) 潜在数据.
研究的目的:
- 使用最新的实验室数据更新移动源的排放计算方法.
- 开发美国移动源排放的第一个自下而上,波动性解决的库存.
- 评估更新排放对空气质量建模预测的影响.
主要方法:
- 利用十多年的实验室数据来参数化排放挥发率和OA潜力.
- 开发了结合过数据的新方法来重建ROC波动分布.
- 包含特定源的过器工件纠正和高级特异化,包括中等挥发性有机化合物 (IVOC).
- 使用社区多层次空气质量 (CMAQ) 模型来模拟空气质量影响.
主要成果:
- 从过数据建立了简单的关系,以重建完整的ROC波动分布.
- 量化移动源为IVOC度的20%-25%和环境OA的4.4%-21.4%提供了贡献.
- 在美国,在各个季节预测微粒有机碳的偏差有所减少 (4.3%-11.3%).
结论:
- 更新的排放清单提供了更准确的移动源对大气组成贡献的表示.
- 改进的移动源排放数据提高了空气质量模型的预测能力.
- 确定了当前排放测量技术中的关键不确定性和研究挑战.
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