Tracing riverine freshwater transport pathways within the Arctic Ocean is key to understanding changes in Arctic Ocean freshwater inventories. Dissolved Ba concentrations have been used in this capacity but are compromised by non-conservative processes. To assess the potential for Ba isotopes to provide insights into the impact of such processes on Arctic Ocean dissolved Ba inventories, Ba concentration and isotope data for surface seawater samples from the Siberian Shelf and Bering Sea/Strait are presented. These samples capture the mixing of riverine freshwater discharged by the rivers Yenisey, Lena and Ob, with Atlantic and Pacific derived seawater, which are traced by relationships between salinity, Ba concentration and δ^138/134Ba. The δ^138/134Ba of net river inputs, following modification by estuarine processes, are constrained to be 0.31 ± 0.04‰, 0.20 ± 0.06‰ and 0.23 ± 0.04‰, for the rivers Yenisey, Lena and Ob respectively. These values are used to estimate an average δ^138/134Ba for Eurasian river freshwater input to the Arctic Ocean of 0.23 ± 0.04‰. The Ba concentration and δ^138/134Ba of Lena River freshwater transported across the Laptev Sea are modified by non-conservative processes. These non-conservative processes do not result in distinctive modification of dissolved Ba concentration-δ^138/134Ba mixing relationships between Eurasian riverine freshwater and Arctic seawater, which unfortunately limits the potential of Ba isotopes to improve tracing riverine freshwater sources in the central Arctic Ocean basins using dissolved Ba inventories. More generally the results of this study help advance understanding of Ba isotope cycling in the environment and their development as an emerging tracer of marine processes.

追踪北冰洋内的河流淡水运输路径是了解北冰洋淡水库存变化的关键。溶解的 Ba 浓度已被用于这种能力，但受到非保守过程的影响。为了评估 Ba 同位素的潜力，以深入了解此类过程对北冰洋溶解 Ba 库存的影响，提供了来自西伯利亚大陆架和白令海/海峡的表层海水样本的 Ba 浓度和同位素数据。这些样本捕获了叶尼塞河、勒拿河和鄂毕河排放的河流淡水与来自大西洋和太平洋的海水的混合，这些海水通过盐度、Ba 浓度和 δ ^138/134 Ba之间的关系进行追踪。δ ^138/134叶尼塞河、勒拿河和鄂毕河经过河口过程改造后，净河流输入的Ba分别限制为0.31±0.04‰、0.20±0.06‰和0.23±0.04‰。这些值用于估计输入到北冰洋的欧亚河流淡水的平均 δ ^138/134 Ba 为 0.23 ± 0.04‰。穿过拉普捷夫海的勒拿河淡水的 Ba 浓度和 δ ^138/134 Ba 被非保守过程改变。这些非保守过程不会导致溶解的 Ba 浓度-δ ^{138/134 的}明显改变欧亚河流淡水和北极海水之间的 Ba 混合关系，不幸的是，这限制了 Ba 同位素利用溶解的 Ba 库存改善北冰洋中部盆地河流淡水源追踪的潜力。更一般地说，这项研究的结果有助于加深对环境中 Ba 同位素循环及其作为海洋过程的新兴示踪剂的发展的理解。