Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077)
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 global...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.898193 2024-09-15T18:24:13+00:00 Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) Gottschalk, Julia Skinner, Luke C Jaccard, Samuel L Waelbroeck, Claire LATITUDE: -44.150000 * LONGITUDE: -14.220000 2019 application/zip, 4 datasets https://doi.pangaea.de/10.1594/PANGAEA.898193 https://doi.org/10.1594/PANGAEA.898193 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.898193 https://doi.org/10.1594/PANGAEA.898193 CC-BY-4.0: Creative Commons Attribution 4.0 International Access constraints: unrestricted info:eu-repo/semantics/openAccess 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, https://doi.org/10.1016/j.quascirev.2019.106067 Atmospheric CO2 variations CALYPSO2 Calypso Corer II Carbon cycle Dansgaard-Oeschger cycles Foraminifera Glacials IMAGES XV - Pachiderme Interstadials Marion Dufresne (1995) MD07-3077 MD159 paleoclimatology Redox-sensitive elements Southern Ocean Stadials dataset publication series 2019 ftpangaea https://doi.org/10.1594/PANGAEA.89819310.1016/j.quascirev.2019.106067 2024-09-03T23:52:03Z 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 findings suggest a consistent pat-tern of increased Southern Ocean convection and/or air-sea CO2 fluxes during northern-hemisphere stadials accompanying AMOC perturbations and promoting a rise in CO2,atm levels, despite potential differences in the magnitude of the forcing, the climate (and hence, AMOC) background conditions and the rate of ocean-atmospheric CO2 fluxes. We find that net ocean car-bon loss, and hence the magnitude of CO2,atm rise, during a glacial is largely determined by the stadial duration. North Atlantic climate anomalies may therefore significantly affect Southern Ocean carbon cycling through oceanic (e.g., 'ventilation' seesaw) and/or atmospheric processes (e.g., Ekman pumping). Other/Unknown Material North Atlantic Southern Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-14.220000,-14.220000,-44.150000,-44.150000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
Atmospheric CO2 variations CALYPSO2 Calypso Corer II Carbon cycle Dansgaard-Oeschger cycles Foraminifera Glacials IMAGES XV - Pachiderme Interstadials Marion Dufresne (1995) MD07-3077 MD159 paleoclimatology Redox-sensitive elements Southern Ocean Stadials |
spellingShingle |
Atmospheric CO2 variations CALYPSO2 Calypso Corer II Carbon cycle Dansgaard-Oeschger cycles Foraminifera Glacials IMAGES XV - Pachiderme Interstadials Marion Dufresne (1995) MD07-3077 MD159 paleoclimatology Redox-sensitive elements Southern Ocean Stadials Gottschalk, Julia Skinner, Luke C Jaccard, Samuel L Waelbroeck, Claire Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) |
topic_facet |
Atmospheric CO2 variations CALYPSO2 Calypso Corer II Carbon cycle Dansgaard-Oeschger cycles Foraminifera Glacials IMAGES XV - Pachiderme Interstadials Marion Dufresne (1995) MD07-3077 MD159 paleoclimatology Redox-sensitive elements Southern Ocean Stadials |
description |
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 findings suggest a consistent pat-tern of increased Southern Ocean convection and/or air-sea CO2 fluxes during northern-hemisphere stadials accompanying AMOC perturbations and promoting a rise in CO2,atm levels, despite potential differences in the magnitude of the forcing, the climate (and hence, AMOC) background conditions and the rate of ocean-atmospheric CO2 fluxes. We find that net ocean car-bon loss, and hence the magnitude of CO2,atm rise, during a glacial is largely determined by the stadial duration. North Atlantic climate anomalies may therefore significantly affect Southern Ocean carbon cycling through oceanic (e.g., 'ventilation' seesaw) and/or atmospheric processes (e.g., Ekman pumping). |
format |
Other/Unknown Material |
author |
Gottschalk, Julia Skinner, Luke C Jaccard, Samuel L Waelbroeck, Claire |
author_facet |
Gottschalk, Julia Skinner, Luke C Jaccard, Samuel L Waelbroeck, Claire |
author_sort |
Gottschalk, Julia |
title |
Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) |
title_short |
Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) |
title_full |
Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) |
title_fullStr |
Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) |
title_full_unstemmed |
Changes in South Atlantic oxygenation, surface temperature and circulation dynamics during termination II and MIS 6 (proxy analyses in sediment core MD07-3077) |
title_sort |
changes in south atlantic oxygenation, surface temperature and circulation dynamics during termination ii and mis 6 (proxy analyses in sediment core md07-3077) |
publisher |
PANGAEA |
publishDate |
2019 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.898193 https://doi.org/10.1594/PANGAEA.898193 |
op_coverage |
LATITUDE: -44.150000 * LONGITUDE: -14.220000 |
long_lat |
ENVELOPE(-14.220000,-14.220000,-44.150000,-44.150000) |
genre |
North Atlantic Southern Ocean |
genre_facet |
North Atlantic Southern Ocean |
op_source |
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, https://doi.org/10.1016/j.quascirev.2019.106067 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.898193 https://doi.org/10.1594/PANGAEA.898193 |
op_rights |
CC-BY-4.0: Creative Commons Attribution 4.0 International Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.89819310.1016/j.quascirev.2019.106067 |
_version_ |
1810464537905725440 |