Simulation of Tropospheric Chemistry over the United States, with Particular Focus on the Free Troposphere and the Role of Lightning Reactive Nitrogen Oxides (NOx)

这项研究包括将特定的自由对流层过程添加到EPA的CMAQ（社区多尺度空气质量）模型中，并检查它们对自由对流层化学的影响，以及随后对边界层臭氧的影响。这些过程包括平流层-对流层交换、行星边界层-对流层交换以及闪电产生的活性氮（NOx）。这些增加的模式将充分利用现有的现场和远程观测数据以及全球模式结果。CMAQ模式在科学界广泛使用，但在模拟自由对流层时表现不佳。这个项目的目标就是改善这种状况。该项目的更广泛影响包括得到一名研究生和两名博士后的支持，并可能改进对流层化学研究和空气质量管理的常用模型。这些模型的改进将有助于更好地评估美国空气质量政策的有效性，并更可靠地测试可供选择的空气污染控制方案。这个项目涉及与其他机构赞助的活动的重要协同作用。除了3名资深科学家、2名来自亨茨维尔阿拉巴马大学的博士后和研究生、1名来自内华达大学拉斯维加斯分校的资深科学家和研究生资助本项目外，还将与2名来自NASA的资深科学家、1名来自NCAR的资深科学家和几名来自EPA的资深科学家合作。

This study involves addition of specific free tropospheric processes to the EPA's CMAQ (Community Multi-scale Air Quality) model, and examination of their impact on free tropospheric chemistry, and subsequent influence on boundary layer ozone. These processes include stratosphere-troposphere exchange, planetary boundary layer - free troposphere exchange, and production of reactive nitrogen (NOx) from lightning. These model additions will make significant use of available in situ and remote observational data, and global model results. The CMAQ model is widely used in the community, but is known to perform poorly in simulations of the free troposphere. The goal of this project is to improve that situation.The broader impacts of this project include the support of a graduate student and two post-doctoral fellows, and likely improvement of well-used models for tropospheric chemistry research and air quality management. These model improvements will allow better assessment of the effectiveness of US air quality policies, and more reliable testing of alternative air pollution control scenarios.This project involves significant synergism with activities sponsored by other agencies. In addition to the 3 senior scientists, 2 post-doctoral fellows and graduate student from the University of Alabama in Huntsville, and the senior scientist and graduate student from the University of Nevada Las Vegas sponsored in this project, there will be coordination with 2 senior scientists from NASA, a senior scientist from NCAR, and several senior scientists from EPA.