The Arctic Oscillation Modulates the Interannual Variation in Particulate Organic Carbon Dispersal on the Eurasian Arctic Shelf

The Arctic Oscillation (AO) affects river plume pathways and material supply by controlling the atmospheric circulation. We analyzed the interannual variation in particulate organic carbon (POC) and hydrological properties in the Eurasian Arctic shelf (EAS) during summer to examine the influence of the AO on POC pathways. Our results characterized the year-round alongshore/offshore distribution of highly depleted δ13C values in the Laptev Sea under various atmospheric conditions. We measured the concentrations of suspended particulate matter, POC and particulate nitrogen in different years on the EAS, and performed biogeochemical analyses (δ13C) and hydrological features in order to trace the pathways of POC associated with river plumes in coastal waters within different AO phases. The AO controls the alongshore/offshore transport of POC by regulating the pathways of plumes, highlighting the significance of the AO in the dynamics and fate of POC. The growing trend in the AO-positive phase potentially affects POC source-to-sink and ecosystem dynamics in the Arctic marginal seas.

北极振荡（AO）通过调节大气环流而影响河流羽流路径和物质供应。本研究分析了欧亚大陆北极大陆架（EAS）夏季中颗粒有机碳（POC）及水文特性的年际变化，以探讨AO对POC路径的影响。研究结果表明，在多种大气条件下，拉普捷夫海沿岸/离岸区域全年高度贫化的δ13C值分布特征。我们测量了不同年份EAS上悬浮颗粒物、POC和颗粒氮的浓度，并进行了生物地球化学分析（δ13C）及水文特征研究，以追踪与河流羽流相关的POC在沿岸水域不同AO阶段中的路径。AO通过调节羽流路径控制POC的沿岸/离岸运输，凸显了AO在POC动态和归宿中的重要性。AO正相期的增长趋势可能对北极边缘海域的POC源汇及生态系统动力学产生影响。