Sulfate Production by Ozone Oxidation in Seasalt Aerosols: Contribution to Global Marine Boundary Layer (MBL) Sulfur Budgets

本项目通过实地观察，研究海盐气溶胶的碱性含量比海水中的碱性含量高，从而导致在较高pH值（较低酸度）下更重要的过程（如臭氧氧化二氧化硫）的重要性增加的假设。 这些过程与二氧化硫通过过氧化氢的水相氧化和通过羟基自由基的气相氧化竞争。 调查将通过在生物初级生产力、云量和季节的各种条件下对气溶胶离子组成进行尺寸分辨测量来完成。 作为气溶胶尺寸的函数的组成测量是重要的，因为碱度增强似乎是更大的尺寸更显着。 这些数据将被用来估计这一机制对全球硫循环的贡献，这项研究将有助于确定可纳入化学传输模型的机制，从而改善海洋边界层硫转化的模拟。 学生将得到支持和参与这个项目。

This project examines, through field observations, the hypothesis that sea-salt aerosol has alkalinity amounts enhanced over that in sea water, which then leads to increased importance of processes that are more important at higher pH (lower acidity), such as oxidation of sulfur dioxide by ozone. These processes compete with the aqueous phase oxidation of sulfur dioxide by hydrogen peroxide, and the gas phase oxidation by hydroxyl radicals. The investigations will be accomplished by making size resolved measurements of aerosol ionic composition under a variety of conditions of biological primary productivity, cloudiness, and season. Composition measurements as a function of aerosol size are important because the alkalinity enhancements appear to be more significant for larger sizes. These data will be used to derive estimates of the contribution of this mechanism to the global sulfur cycle.This research will help define mechanisms that can be incorporated into chemical transport models that should lead to improved simulation of sulfur transformations in the marine boundary layer. Students will be supported and involved in this project.