Abstract Over the last deglaciation there were two transient intervals of pronounced atmospheric CO2 rise; Heinrich Stadial 1 (17.5-15 kyr) and the Younger Dryas (12.9-11.5 kyr). Leading hypotheses accounting for the increased accumulation of CO2 in the atmosphere at these times invoke deep ocean carbon being released from the Southern Ocean and an associated decline in the global efficiency of the biological carbon pump. Here we present new deglacial surface seawater pH and CO2sw records from the Sub-Antarctic regions of the Atlantic and Pacific oceans using boron isotopes measured on the planktic foraminifera Globigerina bulloides. These new data support the hypothesis that upwelling of carbon-rich water in the Sub-Antarctic occurred during Heinrich Stadial 1, and contributed to the initial increase in atmospheric CO2. The increase in CO2sw is coeval with a decline in biological productivity at both the Sub-Antarctic Atlantic and Pacific sites. However, there is no evidence for a significant outgassing of deep ocean carbon from the Sub-Antarctic during the rest of the deglacial, including the second period of atmospheric CO2 rise coeval with the Younger Dryas. This suggests that the second rapid increase in atmospheric CO2 is driven by processes operating elsewhere in the Southern Ocean, or another region.

中文翻译：

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亚南极大西洋和太平洋的早期冰消期二氧化碳释放

摘要 在上一次冰消期中，有两个短暂的大气 CO2 显着上升间隔；Heinrich Stadial 1 (17.5-15 kyr) 和 Younger Dryas (12.9-11.5 kyr)。导致大气中二氧化碳在这些时候积累增加的主要假设是从南大洋释放的深海碳和生物碳泵的全球效率相关的下降。在这里，我们使用在浮游有孔虫 Globigerina Bulloides 上测量的硼同位素，展示了大西洋和太平洋亚南极地区的新冰期表面海水 pH 值和 CO2sw 记录。这些新数据支持了以下假设：亚南极地区富含碳的水上升流发生在 Heinrich Stadial 1 期间，并导致大气 CO2 的初始增加。CO2sw 的增加与亚南极大西洋和太平洋地区生物生产力的下降同时发生。然而，没有证据表明在冰消期的其余时间，包括与新仙女木同时期的大气二氧化碳上升的第二个时期，亚南极地区的深海碳大量释气。这表明大气二氧化碳的第二次快速增加是由在南大洋其他地方或其他地区运行的过程驱动的。