Radiocarbon evidence for alternating northern and southern sources of ventilation of the deep Atlantic carbon pool during the last deglaciation

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Skinner, Luke C., Waelbroeck, Claire, Scrivner, Adam E., Fallon, Stewart J.
• Format: Text
• Language: English
• Published: National Academy of Sciences 2014
• Subjects: Physical Sciences; Southern Ocean; North Atlantic Deep Water; North Atlantic; Northeast Atlantic
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3992695; http://www.ncbi.nlm.nih.gov/pubmed/24706801; https://doi.org/10.1073/pnas.1400668111

This study sheds light on the mechanisms of deglacial atmospheric CO2 rise and, more specifically, on the hypothesized role of a “bipolar seesaw” in deep Atlantic ventilation. Comparing new high-resolution radiocarbon reconstructions from the Northeast Atlantic with existing data from the Southern Ocean, we show that a bipolar ventilation seesaw did indeed operate during the last deglaciation. Whereas today the deep Atlantic’s carbon pool is “flushed” from the north by North Atlantic Deep Water export, it was flushed instead from the south during Heinrich Stadial 1 and the Younger Dryas, in time with sustained atmospheric CO2 rise.