National Exposure Research Laboratory, Office of Research and Development , U.S. Environmental Protection Agency , Research Triangle Park , North Carolina 27711 , United States.
Department of Civil and Environmental Engineering , Carleton University , Ottawa , Canada.
Environ Sci Technol. 2018 Oct 2;52(19):10903-10908. doi: 10.1021/acs.est.8b02496. Epub 2018 Sep 18.
Changing precursor emission patterns in conjunction with stringent health protective air quality standards necessitate accurate quantification of nonlocal contributions to ozone pollution at a location due to atmospheric transport, that by nature predominantly occurs aloft nocturnally. Concerted efforts to characterize ozone aloft on a continuous basis to quantify its contribution to ground-level concentrations, however, are lacking. By applying our classical understanding of air pollution dynamics to analyze variations in widespread surface-level ozone measurements, in conjunction with process-based interpretation from a comprehensive air pollution modeling system and detailed backward-sensitivity calculations that quantitatively link surface-level and aloft pollution, we show that accurate quantification of the amount of ozone in the air entrained from aloft every morning as the atmospheric boundary layer grows is the key missing component for characterizing background pollution at a location, and we propose a cost-effective continuous aloft ozone measurement strategy to address critical scientific gaps in current air quality management. Continuous aloft air pollution measurements can be achieved cost-effectively through leveraging advances in sensor technology and proliferation of tall telecommunications masts. Resultant improvements in ozone distribution characterization at 400-500 m altitude are estimated to be 3-4 times more effective in characterizing the surface-level daily maximum 8-h average ozone (DM8O) than improvements from surface measurements since they directly quantify the amount of pollution imported to a location and furnish key missing information on processes and sources regulating background ozone and its modulation of ground-level concentrations. Since >80% of the DM8O sensitivity to tropospheric ozone is potentially captured through measurements between 200 and 1200 m altitude (a possible design goal for future remote sensing instrumentation), their assimilation will dramatically improve air quality forecast and health advisories.
随着严格的健康保护空气质量标准的实施，需要准确量化由于大气传输导致的臭氧污染的非本地贡献，这种传输本质上主要发生在夜间高空。然而，缺乏对高空臭氧进行连续特征描述以量化其对地面浓度贡献的协同努力。通过将我们对空气污染动力学的经典理解应用于分析广泛的地面臭氧测量值的变化，结合全面的空气污染建模系统的基于过程的解释以及详细的后向敏感性计算，这些计算定量地将地面和高空污染联系起来，我们表明，准确量化每天清晨大气边界层增长时从高空夹带的空气中的臭氧量是描述特定位置背景污染的关键缺失组成部分，并提出了一种具有成本效益的连续高空臭氧测量策略，以解决当前空气质量管理中的关键科学差距。通过利用传感器技术的进步和大量高电信桅杆的普及，可以以具有成本效益的方式实现连续的高空空气污染测量。在 400-500 米高度的臭氧分布特征方面的改进估计比来自地面测量的改进有效 3-4 倍，因为它们直接量化了污染输入到特定位置的量，并提供了有关调节背景臭氧及其对地面浓度调制的过程和来源的关键缺失信息。由于对地面臭氧的 8 小时平均日最大值（DM8O）的敏感性的>80％可能通过在 200 至 1200 米高度之间的测量来捕获（未来远程感应仪器的可能设计目标），因此它们的同化将极大地改善空气质量预测和健康警报。
