Diagnostic and Process-Oriented Modeling Studies of the Tropospheric Cycles of S, N and Ozone

小行星9617378 该项目包括两项独立但相关的调查，重点是大气氧化能力的变化和化学引起的气候变化。第一项研究活动将是对在南半球海洋气溶胶特性鉴定实验（ACE-1）期间飞越南大洋的16次飞行中收集的数据集进行诊断分析和建模。进行这项实验是为了更好地了解控制大气气溶胶的形成和气候变化特性的化学和物理过程。计划使用ACE-1数据集的这一部分进行的具体调查包括：（一）HxOy光化学理论的测试，（二）对流层臭氧光化学的评估，（三）氨氧化及其作为NOx来源的作用的估计，以及（四）气相硫化学和形态及其气体到颗粒转化的调查。 这项研究的另一个好处是，将ACE-1的相关空中测量数据和建模产品合并成一个数据集，提供给国际科学界。 第二项主要调查将是一项面向过程的模拟研究，旨在评估大陆边界层内潮解矿物气溶胶的气相和水相耦合化学。具体而言，这些颗粒作为大气二氧化硫的汇和颗粒硫酸盐的来源的水相氧化的可行性将进行研究。首先，将采用基于美国南部和中国北方数据的地壳起源的内部混合粗气溶胶的一般描述。这些描述将被用来描述矿物气溶胶在高相对湿度下的潮解特性。一个现有的多相大气光化学模式将被用来阐明这些系统的耦合气相和水相化学。这项研究的结果将被用来评估矿物气溶胶在全球范围内的大气硫预算的作用，使用三维化学传输模型在太平洋西北实验室开发的。

9617378 Chameides This project consists of two separate but related investigations which focus on changes in the oxidative capacity of the atmosphere and to chemically-induced climate change. The first research activity will be the diagnostic analysis and modeling of datasets collected in sixteen flights over the Southern Ocean during the Southern Hemisphere Marine Aerosol Characterization Experiment (ACE-1). This experiment was carried out to better understand the chemical and physical processes that control the formation and climate-changing properties of atmospheric aerosols. Specific investigations planned using this portion of the ACE-1 dataset include: (i) testing of HxOy photochemical theory, (ii) assessment of tropospheric ozone photochemistry, (iii) estimates of ammonia oxidation and its role as a source of NOx, and (iv) investigations of gas phase sulfur chemistry and speciation and its gas-to-particle conversion. An added benefit of this study will be the development of a merged dataset of the relevant airborne measurements from ACE-1 as well as the modeling products, which will be made available to the international scientific community. The second major investigation will be a process-oriented modeling study designed to assess the coupled gas- and aqueous-phase chemistry of deliquescent mineral aerosols within the continental boundary layer. Specifically, the viability of aqueous phase oxidation within these particles as a sink of atmospheric sulfur dioxide and a source of particulate sulfate will be investigated. Initially, a generalized description for an internally-mixed coarse aerosol of crustal origin, based on data from the southern United States and from northern China, will be adopted. These descriptions will then be used to characterize the deliquescent characteristics of mineral aerosols at high relative humidity. An existing multi-phase atmospheric photochemical model will be used to elucidate the coupled gas- and aqueous-phase chemistry of these systems. Results from this study will be used to assess the role of mineral aerosols in the atmospheric sulfur budget within a global context using a 3-dimensional Chemical Transport Model developed at the Pacific Northwest Laboratory.