Gottschalk J Skinner LC Lippold J Vogel H Frank N Jaccard SL Waelbroeck C 2016 Millennial-scale climate changes during the last glacial period and deglaciation were accompanied by rapid changes in atmospheric CO2 that remain unexplained. While the role of the Southern Ocean as a 'control valve' on ocean-atmosphere CO2 exchange has been emphasized, the exact nature of this role, in particular the relative contributions of physical (for example, ocean dynamics and air-sea gas exchange) versus biological processes (for example, export productivity), remains poorly constrained. Here we combine reconstructions of bottom-water [O2], export production and (14)C ventilation ages in the sub-Antarctic Atlantic, and show that atmospheric CO2 pulses during the last glacial- and deglacial periods were consistently accompanied by decreases in the biological export of carbon and increases in deep-ocean ventilation via southern-sourced water masses. These findings demonstrate how the Southern Ocean's 'organic carbon pump' has exerted a tight control on atmospheric CO2, and thus global climate, specifically via a synergy of both physical and biological processes. application/pdf https://sonar.ch/global/documents/177740 eng info:eu-repo/semantics/altIdentifier/doi/10.1038/ncomms11539 info:eu-repo/semantics/altIdentifier/pmid/27187527 info:eu-repo/semantics/openAccess Nature communications. - 2016 Atmosphere Carbon Carbon Dioxide Carbon Isotopes Carbon Sequestration Ice Cover Manganese Oceans and Seas Oxidation-Reduction Oxygen Uranium Water Biological and physical controls in the Southern Ocean on past millennial-scale atmospheric CO2 changes. http://purl.org/coar/resource_type/c_6501