Carbon and oxygen stable isotopes measured on benthic foraminifera from IODP Site 323-U1343@en

High latitude deep water upwelling has the potential to control global climate over glacial timescales through the biological pump and ocean-atmosphere CO2 exchange. However, there is currently a lack of continuous long nutrient upwelling records with which to assess this mechanism. In this study we present a new high-resolution multi-species benthic foraminiferal oxygen isotope record for an improved age model and produce the first assessment of the influence of glacial North Pacific Intermediate Water (GNPIW) at 2 km water depth in the Bering Sea. From this, we discuss the extent to which oceanographic changes in Bering Sea upwelling and GNPIW production may have contributed towards deep water upwelling and glacial-interglacial pCO2 changes in the subarctic Pacific over the last 850, 000 years.

高纬度深水上升流可通过生物泵（biological pump）与海-气CO₂交换过程，在冰期时间尺度上调控全球气候。然而目前尚缺乏连续长期的营养盐上升流记录，以评估该机制。本研究构建了适用于优化年代模型的新型高分辨率多物种底栖有孔虫（benthic foraminiferal）氧同位素记录，并首次评估了白令海2千米水深处冰期北太平洋中层水（Glacial North Pacific Intermediate Water, GNPIW）的影响。基于此，我们探讨了过去85万年间，白令海上升流与冰期北太平洋中层水形成的海洋学变化，在多大程度上推动了亚北极太平洋的深水上升流以及冰期-间冰期pCO₂变化。