Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation
Carbon release from the deep ocean at glacial terminations is a critical component of past climate change, but the underlying mechanisms remain poorly understood. We present a 28,000-year high-resolution record of carbonate ion concentration, a key parameter of the global carbon cycle, at 5-km water...
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ftanucanberra:oai:openresearch-repository.anu.edu.au:1885/64791 2024-01-14T10:00:21+01:00 Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation Yu, Jimin Anderson, Robert F. Jin, Zhangdong Menviel, L Zhang, Fei Ryerson, Frederick Rohling, Eelco http://hdl.handle.net/1885/64791 https://doi.org/10.1016/j.quascirev.2014.02.018 https://openresearch-repository.anu.edu.au/bitstream/1885/64791/5/U3488905xPUB999_2014.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/64791/7/01_Yu_Deep_South_Atlantic_carbonate_2014.pdf.jpg unknown Pergamon-Elsevier Ltd 0277-3791 http://hdl.handle.net/1885/64791 doi:10.1016/j.quascirev.2014.02.018 https://openresearch-repository.anu.edu.au/bitstream/1885/64791/5/U3488905xPUB999_2014.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/64791/7/01_Yu_Deep_South_Atlantic_carbonate_2014.pdf.jpg Quaternary Science Reviews Journal article ftanucanberra https://doi.org/10.1016/j.quascirev.2014.02.018 2023-12-15T09:39:09Z Carbon release from the deep ocean at glacial terminations is a critical component of past climate change, but the underlying mechanisms remain poorly understood. We present a 28,000-year high-resolution record of carbonate ion concentration, a key parameter of the global carbon cycle, at 5-km water depth in the South Atlantic. We observe similar carbonate ion concentrations between the Last Glacial Maximum and the late Holocene, despite elevated concentrations in the glacial surface ocean. This strongly supports the importance of respiratory carbon accumulation in a stratified deep ocean for atmospheric CO2 reduction during the last ice age. After ~9μmol/kg decline during Heinrich Stadial 1, deep South Atlantic carbonate ion concentration rose by ~24μmol/kg from the onset of Bølling to Pre-boreal, likely caused by strengthening North Atlantic Deep Water formation (Bølling) or increased ventilation in the Southern Ocean (Younger Drays) or both (Pre-boreal). The ~15μmol/kg decline in deep water carbonate ion since ~10ka is consistent with extraction of alkalinity from seawater by deep-sea CaCO3 compensation and coral reef growth on continental shelves during the Holocene. Between 16,600 and 15,000 years ago, deep South Atlantic carbonate ion values converged with those at 3.4-km water depth in the western equatorial Pacific, as did carbon isotope and radiocarbon values. These observations suggest a period of enhanced lateral exchange of carbon between the deep South Atlantic and Pacific Oceans, probably due to an increased transfer of momentum from southern westerlies to the Southern Ocean. By spreading carbon-rich deep Pacific waters around Antarctica for upwelling, invigorated interocean deep water exchange would lead to more efficient CO2 degassing from the Southern Ocean, and thus to an atmospheric CO2 rise, during the early deglaciation. Article in Journal/Newspaper Antarc* Antarctica North Atlantic Deep Water North Atlantic Southern Ocean Australian National University: ANU Digital Collections Southern Ocean Pacific Quaternary Science Reviews 90 80 89 |
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Open Polar |
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Australian National University: ANU Digital Collections |
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ftanucanberra |
language |
unknown |
description |
Carbon release from the deep ocean at glacial terminations is a critical component of past climate change, but the underlying mechanisms remain poorly understood. We present a 28,000-year high-resolution record of carbonate ion concentration, a key parameter of the global carbon cycle, at 5-km water depth in the South Atlantic. We observe similar carbonate ion concentrations between the Last Glacial Maximum and the late Holocene, despite elevated concentrations in the glacial surface ocean. This strongly supports the importance of respiratory carbon accumulation in a stratified deep ocean for atmospheric CO2 reduction during the last ice age. After ~9μmol/kg decline during Heinrich Stadial 1, deep South Atlantic carbonate ion concentration rose by ~24μmol/kg from the onset of Bølling to Pre-boreal, likely caused by strengthening North Atlantic Deep Water formation (Bølling) or increased ventilation in the Southern Ocean (Younger Drays) or both (Pre-boreal). The ~15μmol/kg decline in deep water carbonate ion since ~10ka is consistent with extraction of alkalinity from seawater by deep-sea CaCO3 compensation and coral reef growth on continental shelves during the Holocene. Between 16,600 and 15,000 years ago, deep South Atlantic carbonate ion values converged with those at 3.4-km water depth in the western equatorial Pacific, as did carbon isotope and radiocarbon values. These observations suggest a period of enhanced lateral exchange of carbon between the deep South Atlantic and Pacific Oceans, probably due to an increased transfer of momentum from southern westerlies to the Southern Ocean. By spreading carbon-rich deep Pacific waters around Antarctica for upwelling, invigorated interocean deep water exchange would lead to more efficient CO2 degassing from the Southern Ocean, and thus to an atmospheric CO2 rise, during the early deglaciation. |
format |
Article in Journal/Newspaper |
author |
Yu, Jimin Anderson, Robert F. Jin, Zhangdong Menviel, L Zhang, Fei Ryerson, Frederick Rohling, Eelco |
spellingShingle |
Yu, Jimin Anderson, Robert F. Jin, Zhangdong Menviel, L Zhang, Fei Ryerson, Frederick Rohling, Eelco Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation |
author_facet |
Yu, Jimin Anderson, Robert F. Jin, Zhangdong Menviel, L Zhang, Fei Ryerson, Frederick Rohling, Eelco |
author_sort |
Yu, Jimin |
title |
Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation |
title_short |
Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation |
title_full |
Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation |
title_fullStr |
Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation |
title_full_unstemmed |
Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation |
title_sort |
deep south atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation |
publisher |
Pergamon-Elsevier Ltd |
url |
http://hdl.handle.net/1885/64791 https://doi.org/10.1016/j.quascirev.2014.02.018 https://openresearch-repository.anu.edu.au/bitstream/1885/64791/5/U3488905xPUB999_2014.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/64791/7/01_Yu_Deep_South_Atlantic_carbonate_2014.pdf.jpg |
geographic |
Southern Ocean Pacific |
geographic_facet |
Southern Ocean Pacific |
genre |
Antarc* Antarctica North Atlantic Deep Water North Atlantic Southern Ocean |
genre_facet |
Antarc* Antarctica North Atlantic Deep Water North Atlantic Southern Ocean |
op_source |
Quaternary Science Reviews |
op_relation |
0277-3791 http://hdl.handle.net/1885/64791 doi:10.1016/j.quascirev.2014.02.018 https://openresearch-repository.anu.edu.au/bitstream/1885/64791/5/U3488905xPUB999_2014.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/64791/7/01_Yu_Deep_South_Atlantic_carbonate_2014.pdf.jpg |
op_doi |
https://doi.org/10.1016/j.quascirev.2014.02.018 |
container_title |
Quaternary Science Reviews |
container_volume |
90 |
container_start_page |
80 |
op_container_end_page |
89 |
_version_ |
1788065164596084736 |