Sistla G, Civerolo K, Hao W, Rao S T
New York State Department of Environmental Conservation, Albany 12222, USA.
J Air Waste Manag Assoc. 2001 Mar;51(3):374-86. doi: 10.1080/10473289.2001.10464282.
The recent regulatory actions toward a longer-term (i.e., 8-hr) average ozone standard have brought forth the potential for many rural areas in the eastern United States to be in noncompliance. However, since a majority of these rural areas have generally few sources of anthropogenic emissions, the measured ozone levels primarily reflect the effects of the transport of ozone and its precursor pollutants and natural emissions. While photochemical grid models have been applied to urban areas to develop ozone mitigation measures, these efforts have been limited to high ozone episode events only and do not adequately cover rural regions. In this study, we applied a photochemical modeling system, RAMS/UAM-V, to the eastern United States from June 1-August 31, 1995. The purpose of the study is to examine the predictive ability of the modeling system at rural monitoring stations that are part of the Clean Air Status Trends Network (CASTNet) and the Gaseous Pollutant Monitoring Program (GPMP). The results show that the measured daily 1-hr ozone maxima and the seasonal average of the daily 1-hr ozone maxima are in better agreement with the predictions of the modeling system than those for the daily 8-hr ozone maxima. Also, the response of the modeling system in reproducing the measured range of ozone levels over the diurnal cycle is poor, suggesting the need for improvement in the treatment of the physical and chemical processes of the modeling system during the nighttime and morning hours if it is to be used to address the 8-hr ozone standard.
近期针对更长期（即8小时）平均臭氧标准采取的监管行动，使得美国东部许多农村地区有可能不符合该标准。然而，由于这些农村地区大多人为排放源普遍较少，所测臭氧水平主要反映了臭氧及其前体污染物的传输以及自然排放的影响。虽然光化学网格模型已应用于城市地区以制定臭氧减排措施，但这些工作仅限于高臭氧事件，并未充分覆盖农村地区。在本研究中，我们于1995年6月1日至8月31日期间，将一个光化学建模系统RAMS/UAM-V应用于美国东部。该研究的目的是检验该建模系统对作为清洁空气状况趋势网络（CASTNet）和气态污染物监测计划（GPMP）一部分的农村监测站的预测能力。结果表明，所测每日1小时臭氧最大值以及每日1小时臭氧最大值的季节平均值，与建模系统的预测结果相比，比每日8小时臭氧最大值的情况更为吻合。此外，建模系统在再现昼夜周期内所测臭氧水平范围方面的响应较差，这表明如果要用于解决8小时臭氧标准问题，需要改进建模系统在夜间和早晨时段对物理和化学过程的处理。
