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

这一合作项目旨在重新审视以前启动的现场实验，以便进一步确定海洋边界层(MBL)的大小分离气溶胶和平衡气流中某些(Cl，Br)卤素物种和自由基的化学浓度和转化。这些大气化学研究将在全球大西洋断面(不来梅港-开普敦)上由德国R/V Polarstein号科考船与一组德国和英国研究人员共同进行，他们致力于进行一套辅助气相(光谱、GC等)和气溶胶特性测量。这些测量将与多相光化学模拟工作相辅相成。这项研究的科学目标是描述和解释沿全球经向巡航样带的多相卤素循环，这将提供一套更广泛的测量并为其提供信息，从而能够深入了解卤素激活、卤素物种Die循环、卤素气相气溶胶分配、气溶胶pH变化性以及关于对流层臭氧和硫(IV)物种寿命和循环的影响的相关推断。由于缺乏关键卤素物种的可靠现场浓度测量，目前对多相卤素转化反应在多相层层中的作用及其对全球海洋大气中非均相大气化学过程的潜在影响的了解受到阻碍。该项目将加强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两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.