Modeling of Tropospheric Photochemistry

在这个项目中，三维化学模型将用于研究对流层化学问题。(1)量化北美氮氧化物在不同季节向全球大气的出口量，以及非甲烷烃对这种出口量的调节作用。北美的化石燃料燃烧排放了大量的氮氧化物，但只有一小部分这种物质出口到大陆边界层之外，在那里它影响着全球范围内的对流层化学。(2)北美化石燃料燃烧对遥远对流层氮氧化物浓度的贡献将通过将三维模式的尺度从大陆尺度扩展到北半球来确定。将调查从北美出口的氮氧化物的最终命运及其对全球对流层化学的影响。(3)研究对流层上层氮自由基和氧化氢自由基浓度的控制因素。目前人们对这些化学因素知之甚少。将在最近和即将进行的飞机运动的数据支持下进行一项全面的理论研究，以便确定不同的制度并检查对化学和气象变量的敏感性。(4)大气中丙酮的来源目前还不能定量地知道。丙酮及其非甲烷烃前体的三维模型研究将进行。将对不同地区的模拟和观测大气浓度进行详细的比较。

9612282 Jacob In this project, 3-dimensional chemical models will be used to investigate issues in tropospheric chemistry. (1) The export of nitrogen oxides from North America to the global atmosphere in different seasons, and the role played by non-methane hydrocarbons in modifying this export, will be quantified. Large amounts of nitrogen oxides are emitted by fossil fuel combustion in North America, but only a fraction of this material is exported out of the continental boundary layer where it affects tropospheric chemistry on a global scale. (2) The contribution of fossil fuel combustion in North America to concentrations of nitrogen oxide in the remote troposphere will be determined by expanding the scale of the 3-dimensional model from continental-scale to the northern hemisphere. The ultimate fate of the nitrogen oxides exported from North America, and its influence on global tropospheric chemistry, will be investigated. (3) The factors controlling the concentration of nitrogen and hydrogen oxide radicals in the upper troposphere will be studied. These chemical factors are currently poorly understood. A comprehensive theoretical study will be conducted, supported by data from recent and upcoming aircraft campaigns, in order to define the different regimes and to examine the sensitivity to chemical and meteorological variables. (4) The sources of atmospheric acetone are currently not known quantitatively. A 3-dimensional model study of acetone and its non-methane hydrocarbon precursors will be conducted. Detailed comparisons of simulated and observed atmospheric concentrations in different regions will be carried out.