Collaborative research: Chromophoric dissolved organic matter (CDOM) and lignin phenols as tracers of water masses and biogeochemical processes in the Arctic Ocean

AMON 0713991德克萨斯农工大学-加尔维斯顿基金会被提供来调查陆源有机物的分布及其荧光性质，以增进对北极盐跃层中的通风过程以及北冰洋陆源有机碳的物理、生物和光化学通量的了解。主要研究人员提出了一系列假设进行检验：假设1：陆源溶解有机质(DOM)和有色溶解有机质(CDOM)是河水的敏感示踪剂，携带着其他淡水示踪剂(如盐度、碱度、钡、d18O)所不具备的独特来源信息，特别是在加拿大盆地。假设2：陆源溶解有机物和CDOM主要在海冰形成和卤水排出过程中被注入到表层混合层以下，是北极盐跃层水体通风的有用示踪剂。(他们认为，详细的荧光分析将使他们能够区分不同的来源，并为未来开发更具体的原位探测器。)假设4：DOM中木质素酚的尺寸分布提供了北极陆源DOM分解程度的定性指标。北冰洋的淡水收支及其十年时间尺度和更长时间的变异性，可能对全球海洋环流产生重要影响，如经圈翻转环流的调制和气候。该项目将为研究和洞察从世界一些主要河流系统排入北冰洋的淡水的路径和命运提供工具。

Amon 0713991Texas A&M University - GalvestonFunds are provided to investigate the distribution of terrigenous organic matter and its fluorescent properties to improve understanding of ventilation processes in the Arctic halocline as well as the physical, biological, and photochemical fluxes of terrigenous organic carbon in the Arctic Ocean. The principal investigators propose a series of hypotheses for testing:Hypothesis 1: Terrigenous dissolved organic matter (DOM) and chromophoric dissolved organic matter (CDOM) are sensitive tracers of river water that carry unique source information that is not readily available with other freshwater tracers (e.g. salinity, alkalinity, barium, d18O), especially in the Canada Basin.Hypothesis 2: Terrigenous DOM and CDOM are primarily injected below the surface mixed layer during sea-ice formation and brine rejection and are useful tracers of the ventilation of Arctic halocline waters.Hypothesis 3: The Arctic halocline is a multilayer system with each layer having distinct origins. (They believe that detailed fluorescence analyses will allow them to distinguish the different origins and develop more specific in situ probes for the future.)Hypothesis 4: The size distribution of lignin phenols in DOM provides a qualitative index of the extent of decomposition of terrigenous DOM in the Arctic.The freshwater budget of the Arctic Ocean, and its variability of decadal time scales and longer, has the potential for important impacts on global ocean circulation, such as modulation of the meridional overturning circulation, and climate. This project will provide tools for the study of and insights into the pathways and fate of freshwater discharged into the Arctic Ocean from some of the world's major river systems.