Air Quality Research Center, University of California-Davis, Davis, CA, USA.
Department of Natural Resources and Environmental Science, University of Nevada-Reno, Reno, NV 89557, USA.
Sci Total Environ. 2015 Oct 15;530-531:505-518. doi: 10.1016/j.scitotenv.2015.03.091. Epub 2015 Apr 10.
The proposed revision of the United States (US) air quality standard for ozone will result in violations in sparsely populated remote rural areas in the Western US. Replicating air quality as measured at surface monitoring sites by modeling is particularly difficult in this region due to complex terrain, poorly represented in regional and global models, and uncertainties in emission rates and timing at all scales (locally as well as hundreds to thousands of km upwind). As an alternative method, a fully empirical, receptor-based scheme using in situ aerosol composition and simple meteorological variables to simulate ozone (O3) measurements was tested and found to produce O3 simulation results comparable in uncertainty to regional modeling, and supporting trajectory-based identification of O3 source regions. This approach was tested using two widely-separated (650 km) high altitude (approx. 2 km above sea level) monitoring sites, Lassen Volcanic National Park, in northern California (LAVO) and Great Basin National Park in eastern Nevada (GRBA). Comparing correlations between observed O3 and aerosols, and examining back-trajectories associated with peak concentrations for the two sites permitted distinguishing among local, distant North American, and Asian sources of particulate matter (PM2.5) and O3. This analysis indicates that anthropogenic enhancement of O3 at LAVO is primarily due to transport from Asia. Asia is also the dominant source of anthropogenic O3 at GRBA in spring, but regional North American sources of O3 appear to drive additional ozone peaks in late summer and fall at this more interior site.
美国（US）拟修订臭氧空气质量标准，这将导致美国西部人口稀少的偏远农村地区臭氧超标。由于地形复杂，区域和全球模型对其代表性不足，以及排放率和排放时间在所有尺度（局部尺度以及数百到数千公里上风方向）上存在不确定性，通过建模来复制地面监测站点测量的空气质量尤其具有挑战性。作为一种替代方法，使用现场气溶胶成分和简单气象变量的完全经验性、基于受体的方案来模拟臭氧（O3）测量值，经过测试，发现该方案可以产生与区域建模相当的 O3 模拟结果，并且支持基于轨迹的 O3 源区识别。该方法使用两个相距较远（650 公里）的高海拔（约 2 公里海拔）监测站点进行了测试，分别是加利福尼亚州北部的拉森火山国家公园（LAVO）和内华达州东部的大盆地国家公园（GRBA）。比较两个站点观测到的 O3 和气溶胶之间的相关性，并检查与峰值浓度相关的后向轨迹，可以区分本地、遥远的北美和亚洲的颗粒物（PM2.5）和 O3 源。该分析表明，LAVO 的 O3 人为增强主要是由于亚洲的传输。亚洲也是 GRBA 春季人为 O3 的主要来源，但在这个更内陆的站点，夏季和秋季的区域北美 O3 来源似乎会导致额外的臭氧峰值。
