Models for Photochemistry and Transport off the East Coast of North America: Impact of Mesoscale Dynamics, Aqueous Chemistry and Fog

最近对流层痕量物种的测量是作为北大西洋区域实验（NARE）的一部分在北大西洋沿岸的偏远海域进行的。这些物种包括臭氧；影响人类健康、农作物和生态系统；羟基自由基控制着包括甲烷和卤代烃在内的多种物种在对流层的寿命；还有氮氧化物。这些测量结果提供了输出到大西洋的受污染大陆气团的化学成分的重要信息。初步结果表明，活性氮的大量去除发生在大陆空气穿过海洋的过程中，这可能与雾事件有关。该项目将使用PI开发的大陆和城市/区域综合模型调查化学活性物种的出口。城市/区域尺度模式代表城市羽流在水面上的光化学演变，并包括垂直分层环流对水面的影响。模型化学将得到加强，以包括水反应和雾事件的表示。该项目可以确定导致硝酸和PAN去除的条件，并量化这些活性含氮物种的去除率。将进行模式结果与NARE测量数据的比较，以评估和改进模式模拟污染大陆气团在大西洋上空的化学处理和运输的能力。

9526184 Sillman Recent measurements of tropospheric trace species were performed as part of the North Atlantic Regional Experiment (NARE) at remote marine locations along the North Atlantic coast. These species include ozone; which impacts human health, agricultural crops and ecosyqtems; hydroxyl radical, which controls tropospheric lifetimes of a wide range of species, including methane and halogenated hydrocarbons; and nitrogen oxides. These measurements provide important information about the chemistry of polluted continental air masses exported to the Atlantic Ocean. Preliminary results suggest that significant removal of reactive nitrogen occurs as continental air travels over the ocean, possibly associated with fog events. This project will investigate the export of chemically reactive species using a combined continental- and urban/regional-scale model developed by the PI. The urban/regional-scale model represents the photochemical evolution of urban plumes transported over water and includes the impact of vertically stratified circulation over water. The model chemistry will be enhanced to include aqueous reactions, and representation of fog events. This project could identify conditions that lead to the removal of nitric acid and PAN and quantify removal rates for these reactive nitrogen-containing species. Comparison of the model results with the NARE measurement data will be performed to assess and refine the model's ability to simulate chemical processing and transport of polluted continental air masses as they travel over the Atlantic Ocean.