Enhanced ocean-atmosphere carbon partitioning via the carbonate counter pump during the last deglacial

Duchamp-Alphonse, Stéphanie; Siani, Giuseppe; Michel, Elisabeth; Beaufort, Luc; Gally, Yves; Jaccard, Samuel (2018). Enhanced ocean-atmosphere carbon partitioning via the carbonate counter pump during the last deglacial. Nature communications, 9(1) Nature Publishing Group 10.1038/s41467-018-04625-7

Preview

Text Duchamp-Alphonse et al., 18.pdf - Published Version Available under License Creative Commons: Attribution (CC-BY). Download (4MB) | Preview

Several synergistic mechanisms were likely involved in the last deglacial atmospheric pCO2 rise. Leading hypotheses invoke a release of deep-ocean carbon through enhanced convec- tion in the Southern Ocean (SO) and concomitant decreased efficiency of the global soft- tissue pump (STP). However, the temporal evolution of both the STP and the carbonate counter pump (CCP) remains unclear, thus preventing the evaluation of their contributions to the pCO2 rise. Here we present sedimentary coccolith records combined with export pro- duction reconstructions from the Subantarctic Pacific to document the leverage the SO biological carbon pump (BCP) has imposed on deglacial pCO2. Our data suggest a weakening of BCP during the phases of carbon outgassing, due in part to an increased CCP along with higher surface ocean fertility and elevated [CO2aq]. We propose that reduced BCP efficiency combined with enhanced SO ventilation played a major role in propelling the Earth out of the last ice age.

Interest & Impact

Downloads

156 since deposited on 20 Jun 2018
32 in the past 12 months

Citations

5 Citations in Web of Science ®
6 Citations in Scopus

Search

in Google Scholar™

Services

Actions (login required)

Edit item

Actions (login required)

Edit item