Discharges of freshwater into the Arctic Ocean from rivers in Eurasia and North America account for approximately 11% of the global riverine freshwater input, and contain weathering products including dissolved continental boron. Much of this freshwater flows into the North Atlantic Ocean, primarily via the East Greenland Current carrying the Polar Water with salinity <34.4. As a result, the input of boron-containing freshwater could cause the boron content in low salinity water to deviate from predictions based on the open ocean ratio for boron to salinity. Significant deviations from predictions would affect carbonate system calculations for seawater in the Arctic. We analysed the boron concentrations and salinity for seawater samples (n = 249; salinity = 30–35) collected primarily from the areas of the East Greenland Current downstream of the influence of freshwater inputs, and from northward flowing Atlantic Water in the vicinity of Iceland. Unexpectedly, the mean boron to salinity ratio of 0.1324 ± 0.0008 mg kg⁻¹‰⁻¹ was similar to the ratio for the open ocean (0.1336 mg kg⁻¹‰⁻¹). The absence of anomalies in the boron to salinity ratio measured for our samples provides compelling evidence that continental freshwater flowing into the Arctic Ocean probably contains little dissolved boron, and hence has a negligible effect on the boron to salinity ratio in the Arctic Ocean. Our results also indicate that known deviations in the polar water alkalinity from predictions based on the open ocean alkalinity-salinity relationship stem largely from other sources, primarily inputs of carbonate-rich freshwater.

从欧亚大陆和北美的河流向北冰洋排放的淡水约占全球河流淡水输入量的11％，并且含有包括溶解的大陆硼在内的风化产物。这些淡水的大部分流入北大西洋，主要是通过东格陵兰洋流携带盐分<34.4的极地水。结果，输入的含硼淡水可能导致低盐度水中的硼含量偏离基于开放海洋中硼与盐度比的预测。与预测的显着偏差会影响北极海水的碳酸盐系统的计算。我们分析了海水样品中的硼浓度和盐度（n = 249; 盐度= 30-35）主要从淡水输入影响下游的东格陵兰洋流地区以及冰岛附近向北流动的大西洋水收集。出乎意料的是，平均硼盐度比为0.1324±0.0008 mg kg ^-1 ‰ ^-1，与开阔海洋的比例相似（0.1336 mg kg ^-1 ‰ ^-1）。对于我们的样品测得的硼盐度比值没有异常，这提供了令人信服的证据，表明流入北冰洋的大陆淡水可能含有极少的溶解硼，因此对北冰洋的硼盐度比影响可忽略不计。我们的结果还表明，根据基于开放海洋碱度-盐度关系的预测得出的极性水碱度的已知偏差主要来自其他来源，主要是富含碳酸盐的淡水输入。