Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current
The timing of the onset of the Antarctic Circumpolar Current (ACC) is a crucial event of the Cenozoic because of its cooling and isolating effect over Antarctica. It is intimately related to the glaciations occurring throughout the Cenozoic from the Eocene–Oligocene (EO) transition (≈ 34 Ma) to the...
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Online Access: | https://doi.org/10.5194/cp-10-1957-2014 https://cp.copernicus.org/articles/10/1957/2014/ |
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ftcopernicus:oai:publications.copernicus.org:cp25224 2023-05-15T13:54:27+02:00 Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current Ladant, J.-B. Donnadieu, Y. Dumas, C. 2018-09-27 application/pdf https://doi.org/10.5194/cp-10-1957-2014 https://cp.copernicus.org/articles/10/1957/2014/ eng eng doi:10.5194/cp-10-1957-2014 https://cp.copernicus.org/articles/10/1957/2014/ eISSN: 1814-9332 Text 2018 ftcopernicus https://doi.org/10.5194/cp-10-1957-2014 2020-07-20T16:24:53Z The timing of the onset of the Antarctic Circumpolar Current (ACC) is a crucial event of the Cenozoic because of its cooling and isolating effect over Antarctica. It is intimately related to the glaciations occurring throughout the Cenozoic from the Eocene–Oligocene (EO) transition (≈ 34 Ma) to the middle Miocene glaciations (≈ 13.9 Ma). However, the exact timing of the onset remains debated, with evidence for a late Eocene setup contradicting other data pointing to an occurrence closer to the Oligocene–Miocene (OM) boundary. In this study, we show the potential impact of the Antarctic ice sheet on the initiation of a strong proto-ACC at the EO boundary. Our results reveal that the regional cooling effect of the ice sheet increases sea ice formation, which disrupts the meridional density gradient in the Southern Ocean and leads to the onset of a circumpolar current and its progressive strengthening. We also suggest that subsequent variations in atmospheric CO 2 , ice sheet volumes and tectonic reorganizations may have affected the ACC intensity after the Eocene–Oligocene transition. This allows us to build a hypothesis for the Cenozoic evolution of the Antarctic Circumpolar Current that may provide an explanation for the second initiation of the ACC at the Oligocene–Miocene boundary while reconciling evidence supporting both early Oligocene and early Miocene onset of the ACC. Text Antarc* Antarctic Antarctica Ice Sheet Sea ice Southern Ocean Copernicus Publications: E-Journals Antarctic Southern Ocean The Antarctic Climate of the Past 10 6 1957 1966 |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
description |
The timing of the onset of the Antarctic Circumpolar Current (ACC) is a crucial event of the Cenozoic because of its cooling and isolating effect over Antarctica. It is intimately related to the glaciations occurring throughout the Cenozoic from the Eocene–Oligocene (EO) transition (≈ 34 Ma) to the middle Miocene glaciations (≈ 13.9 Ma). However, the exact timing of the onset remains debated, with evidence for a late Eocene setup contradicting other data pointing to an occurrence closer to the Oligocene–Miocene (OM) boundary. In this study, we show the potential impact of the Antarctic ice sheet on the initiation of a strong proto-ACC at the EO boundary. Our results reveal that the regional cooling effect of the ice sheet increases sea ice formation, which disrupts the meridional density gradient in the Southern Ocean and leads to the onset of a circumpolar current and its progressive strengthening. We also suggest that subsequent variations in atmospheric CO 2 , ice sheet volumes and tectonic reorganizations may have affected the ACC intensity after the Eocene–Oligocene transition. This allows us to build a hypothesis for the Cenozoic evolution of the Antarctic Circumpolar Current that may provide an explanation for the second initiation of the ACC at the Oligocene–Miocene boundary while reconciling evidence supporting both early Oligocene and early Miocene onset of the ACC. |
format |
Text |
author |
Ladant, J.-B. Donnadieu, Y. Dumas, C. |
spellingShingle |
Ladant, J.-B. Donnadieu, Y. Dumas, C. Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current |
author_facet |
Ladant, J.-B. Donnadieu, Y. Dumas, C. |
author_sort |
Ladant, J.-B. |
title |
Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current |
title_short |
Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current |
title_full |
Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current |
title_fullStr |
Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current |
title_full_unstemmed |
Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current |
title_sort |
links between co2, glaciation and water flow: reconciling the cenozoic history of the antarctic circumpolar current |
publishDate |
2018 |
url |
https://doi.org/10.5194/cp-10-1957-2014 https://cp.copernicus.org/articles/10/1957/2014/ |
geographic |
Antarctic Southern Ocean The Antarctic |
geographic_facet |
Antarctic Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Antarctica Ice Sheet Sea ice Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Sea ice Southern Ocean |
op_source |
eISSN: 1814-9332 |
op_relation |
doi:10.5194/cp-10-1957-2014 https://cp.copernicus.org/articles/10/1957/2014/ |
op_doi |
https://doi.org/10.5194/cp-10-1957-2014 |
container_title |
Climate of the Past |
container_volume |
10 |
container_issue |
6 |
container_start_page |
1957 |
op_container_end_page |
1966 |
_version_ |
1766260358879641600 |