Collaborative Research: Multiphase Halogen Chemistry in the Atlantic Marine Boundary Layer

这个合作项目旨在重新审视以前发起的现场实验，以进一步表征化学浓度和某些（氯，溴）卤素物种和自由基的大小隔离气溶胶和平衡的气体流的海洋边界层（MBL）的转换。这些大气化学研究将在德国研究船R/V Polarstern上对全球大西洋断面（不来梅港-开普敦）进行，与德国和英国的一组调查人员一起进行一套辅助气相（光谱、GC等）和气溶胶特性测量。这些测量将与多相光化学建模工作相补充。本研究的科学目标是表征和解释沿着全球纬向巡航样带的多相卤素循环，将提供更广泛的测量结果，并从中了解卤素活化、卤素物种昼夜循环、卤素气相气溶胶分区、气溶胶pH值变化以及对流层臭氧和硫（IV）物种寿命和循环影响的相关推论。 目前的理解的作用，多相卤素转化反应的MBL和它们的潜在影响，在全球海洋大气中的非均质大气化学过程的关键卤素物种缺乏可靠的现场浓度测量受到阻碍。该项目将提高我们对自然卤素循环化学在人为扰动方面的重要性的理解。该项目将加强机构间和国际一级的研究和教育伙伴关系。

This collaborative project seeks to revisit previously initiated field experiments in order to further characterize the chemical concentrations and transformations of certain (Cl, Br) halogen species and radicals in both size segregated aerosols and equilibrated gas streams of the marine boundary layer (MBL). These atmospheric chemical studies will be carried out on a global Atlantic Ocean transect (Bremerhaven - Capetown) aboard the German research vessel R/V Polarstern, conjointly with a team of German and British investigators engaged making a suite of ancillary gas-phase (spectroscopic, GC etc), and aerosol characterization measurements. These measurements will be complemented with multiphase photochemical modeling efforts. The scientific goal of this study, to characterize and interpret multiphase halogen cycling along a global meridional cruise transect, will provide and be informed by the broader suite of measurements enabling insight into halogen activation, halogen species diel cycling, halogen gas-phase aerosol partitioning, aerosol pH variability together with related inferences on the impacts on lifetimes and cycling of tropospheric ozone and sulfur (IV) species. Current understanding of the role of multiphasic halogen transformation reactions in the MBL and their potential impact on heterogeneous atmospheric chemical processes in the global marine atmosphere is hampered by a lack of reliable field concentration measurements of key halogen species. The project will enhance our understanding of the importance of natural halogen cycle chemistry in relation to anthropogenic perturbation. The project will enhance research and education partnerships at both inter-institutional and international levels.