Development of Numerical Methods for Combined Gas and Aqueous Phase Chemistry in 3-Dimensional Global Models

小行星9422323 近年来，二维全球模拟的结果表明，气相碳氢化合物化学和水化学都有显着的对流层的影响，特别是关于对流层的重要物种臭氧，氮氧化物，和羟基自由基。 对这些光化学影响的完整分析需要三维模拟。 最近三维化学示踪剂模式（CTMs）已被应用于光化学活性对流层物种，然而，CTMs的应用受到限制的计算限制与光化学生产和损失的计算。 PI开发了一种创新的数值方法来求解对流层化学方程。 该方法利用对流层奇数水的特殊性质，得到了光化学产生和损失方程的收敛隐式解。 通过利用对流层的特定光化学特性作为解决方案的一部分，该方法在计算上非常快。 在这个项目中，现有的能力将在两个方向上扩展。 首先，将开发技术，包括水的光化学作为数字代码的一部分。 第二，将完成对三维全球模式中对流层活性氮循环的气相和水相化学分析。 这种分析将导致直接比较模拟活性氮物种和最近的测量与北大西洋区域实验。

9422323 Sillman In recent years, results from two-dimensional global simulations have demonstrated that gas-phase hydrocarbon chemistry and aqueous chemistry both have significant impacts in the troposphere, particularly with regard to the important tropospheric species ozone, NOx, and hydroxyl radical. A complete analysis of these photochemical impacts requires a three-dimensional simulation. Recently three-dimensional chemical tracer models (CTMs) have been applied to photochemically active tropospheric species, however, the application of CTMs has been limited by computational constraints associated with the calculation of photochemical production and loss. The PI has developed an innovative numerical approach to solving the equations of tropospheric chemistry. This method uses special properties of tropospheric odd hydroeen to obtain a convergent implicit solution to the equations of photochemical production and loss. By utilizing specific photochemical properties of the troposphere as part of the solution, the method is computationally very fast. In this project, the existing capabilities will be extended in two directions. First, techniques will be developed to include aqueous photochemistry as part of the numerical code. Second, an analysis of the cycle of tropospheric reactive nitrogen in three-dimensional global models with gas-and aqueous-phase chemistry will be completed. This analysis will lead to direct comparisons between simulated reactive nitrogen species and recent measurements associated with the North Atlantic Regional Experiment.