Changes in ocean circulation are considered a major driver of centennial‐to‐millennial scale climate variability during the last deglaciation. Using four sediment records from the Nordic Seas, we studied radiocarbon ventilation ages in subsurface and bottom waters to reconstruct past variations in watermass overturning. Planktic foraminiferal ages show significant spatial variability over most of the studied period. These differences suggest that the ventilation of the shallower subsurface waters is strongly influenced by local conditions such as sea‐ice and meltwater input, changes in mixed‐layer depth, and/or variable contributions of water masses with different ¹⁴C signatures. Despite covering a significant water depth range, the benthic foraminiferal records show common long‐term patterns, with generally weaker ventilation during stadials and stronger during interstadials. The Greenland Sea record differs the most from the other records, which can be explained by the greater depth and the geographical distance of this site. The benthic records reflect regional shifts in deep convection and suggest that the deep Nordic Seas have been generally bathed by a single, though changing, deep‐water mass analogous to the present‐day Greenland Sea Deep Water. Since significant offsets in ventilation ages are yielded by different taxonomic or ecological groups of benthic foraminifera, the use of uniform material seems a prerequisite to reconstruct bottom water ventilation histories.

中文翻译：

---

从上层-底层的放射性碳年龄偏移推导的北欧海的通气史

在最后一次冰消期间，海洋环流的变化被认为是百年至千年尺度气候变化的主要驱动力。利用来自北欧海域的四个沉积物记录，我们研究了地下和底部水域的放射性碳通风年龄，以重建过去的水体倾覆变化。在大多数研究时期中，浮游有孔虫年龄显示出显着的空间变异性。这些差异表明，较浅的地下水的通风受到当地条件的强烈影响，例如海冰和融水的输入，混合层深度的变化和/或不同¹⁴的水团的变化贡献。C签名。尽管底栖有孔虫记录覆盖了很大的水深范围，但它们显示出常见的长期模式，在蓄水池期间通气通常较弱，而在陆栖期间则较强。格陵兰海的记录与其他记录的差异最大，这可以通过该站点更大的深度和更远的地理距离来解释。底栖记录反映了深对流的区域变化，并表明北欧深海总体上是由一个单一的，但不断变化的深水海域沐浴的，这类似于当今的格陵兰海深水。由于底栖有孔虫的不同生物分类或生态学类别导致了通风年龄的显着抵消，因此使用统一的材料似乎是重建底水通风历史的先决条件。