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.