Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) ...

• Main Authors: Gottschalk, Julia, Skinner, Luke C, Jaccard, Samuel L, Waelbroeck, Claire
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2019
• Subjects: Atmospheric CO2 variations; Carbon cycle; Dansgaard-Oeschger cycles; Foraminifera; Glacials; Interstadials; paleoclimatology; Redox-sensitive elements; Southern Ocean; Stadials; Calypso Corer II; MD159; Marion Dufresne 1995; Laurie; Luke
• Online Access: https://dx.doi.org/10.1594/pangaea.898193; https://doi.pangaea.de/10.1594/PANGAEA.898193

Past millennial-scale changes in atmospheric CO2 (CO2,atm) levels have often been attributed to variations in the overturning timescale of the ocean that result in changes in the marine carbon inventory. There remains a paucity of proxy evidence that documents changes in marine carbon storage globally, and that links them to distinct abrupt climate variability in the northern hemi-sphere that involve perturbations of the Atlantic Meridional Overturning Circulation (AMOC). The last two glacial periods were suggested to differ in the extent and sensitivity of the AMOC to changes, and therefore provide an opportunity to study their role in marine carbon cycling. Here, we reconstruct variations in respired carbon storage (via oxygenation) and the AMOC 'geometry' (via carbonate ion saturation) in the deep South Atlantic during the past two glacial periods. We infer decreases in deep South Atlantic respired carbon levels at times of weakened AMOC and rising CO2,atm concentrations during both glacial periods. These ... : Supplement to: Gottschalk, Julia; Skinner, Luke C; Jaccard, Samuel L; Menviel, Laurie; Nehrbass-Ahles, Christoph; Waelbroeck, Claire (2020): Southern Ocean link between changes in atmospheric CO2 levels and northern-hemisphere climate anomalies during the last two glacial periods. Quaternary Science Reviews, 230, 106067 ...