ABSTRACT Water samples from the different basins of the Baltic Sea and North Sea were collected during four cruises taken place in 2016–2017. Altogether 60 water samples for 3H activity concentration and 120 water samples for stable isotopes ratio (δ18O and δ2H) were analysed. Exceptionally strong inflow activity from North Sea to the Baltic Sea occurred prior our surveys. The data obtained enabled comprehensive evaluation of tritium and stable isotopes distribution in waters of Baltic Sea and contributing inputs, including riverine and atmospheric freshwater flux and saline water inflow through the Danish Straits. By comparing with the previous studies, we noticed a tendency toward an increase in the δ18O and δ2H values of zero-salinity component over time, which may be due to climate change. In the case of tritium, the influence of artificial sources has also been noticed.

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2016-2017 年波罗的海海水氚和稳定同位素

摘要 在 2016-2017 年进行的四次航行中收集了来自波罗的海和北海不同盆地的水样。总共分析了 3H 活性浓度的 60 个水样和稳定同位素比（δ18O 和 δ2H）的 120 个水样。在我们的调查之前，从北海到波罗的海的流入活动异常强烈。获得的数据能够对波罗的海水域中氚和稳定同位素的分布以及贡献的输入进行综合评估，包括河流和大气淡水通量以及通过丹麦海峡的咸水流入。通过与之前的研究相比，我们注意到零盐度分量的 δ18O 和 δ2H 值随时间增加的趋势，这可能是由于气候变化。在氚的情况下，