Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception
We present downcore records of redox-sensitive authigenic uranium (U) and manganese (Mn) concentrations based on five marine sediment cores spanning a meridional transect encompassing the Subantarctic and the Antarctic zones in the Southwest Indian Ocean covering the last glacial cycle. These record...
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ftcopernicus:oai:publications.copernicus.org:cpd93523 2023-05-15T13:31:40+02:00 Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception Amsler, Helen Eri Thöle, Lena Mareike Stimac, Ingrid Geibert, Walter Ikehara, Minoru Kuhn, Gerhard Esper, Oliver Jaccard, Samuel Laurent 2021-04-20 application/pdf https://doi.org/10.5194/cp-2021-29 https://cp.copernicus.org/preprints/cp-2021-29/ eng eng doi:10.5194/cp-2021-29 https://cp.copernicus.org/preprints/cp-2021-29/ eISSN: 1814-9332 Text 2021 ftcopernicus https://doi.org/10.5194/cp-2021-29 2021-04-26T16:22:15Z We present downcore records of redox-sensitive authigenic uranium (U) and manganese (Mn) concentrations based on five marine sediment cores spanning a meridional transect encompassing the Subantarctic and the Antarctic zones in the Southwest Indian Ocean covering the last glacial cycle. These records signal lower bottom water oxygenation during glacial climate intervals and generally higher oxygenation during warm periods, consistent with climate-related changes in deep ocean remineralised carbon storage. Regional changes in the export of siliceous phytoplankton to the deep-sea may have entailed a secondary influence on oxygen levels at the water-sediment interface, especially in the Subantarctic Zone. The rapid reoxygenation during the deglaciation is in line with increased ventilation and enhanced upwelling after the Last Glacial Maximum (LGM), which, in combination, conspired to transfer previously sequestered remineralised carbon to the surface ocean and the atmosphere, contributing to propel the Earth’s climate out of the last ice age. These records highlight the yet insufficiently documented role the southern Indian Ocean played in the air-sea partitioning of CO 2 on glacial-interglacial timescales. Text Antarc* Antarctic Copernicus Publications: E-Journals Antarctic Indian The Antarctic |
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Copernicus Publications: E-Journals |
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English |
description |
We present downcore records of redox-sensitive authigenic uranium (U) and manganese (Mn) concentrations based on five marine sediment cores spanning a meridional transect encompassing the Subantarctic and the Antarctic zones in the Southwest Indian Ocean covering the last glacial cycle. These records signal lower bottom water oxygenation during glacial climate intervals and generally higher oxygenation during warm periods, consistent with climate-related changes in deep ocean remineralised carbon storage. Regional changes in the export of siliceous phytoplankton to the deep-sea may have entailed a secondary influence on oxygen levels at the water-sediment interface, especially in the Subantarctic Zone. The rapid reoxygenation during the deglaciation is in line with increased ventilation and enhanced upwelling after the Last Glacial Maximum (LGM), which, in combination, conspired to transfer previously sequestered remineralised carbon to the surface ocean and the atmosphere, contributing to propel the Earth’s climate out of the last ice age. These records highlight the yet insufficiently documented role the southern Indian Ocean played in the air-sea partitioning of CO 2 on glacial-interglacial timescales. |
format |
Text |
author |
Amsler, Helen Eri Thöle, Lena Mareike Stimac, Ingrid Geibert, Walter Ikehara, Minoru Kuhn, Gerhard Esper, Oliver Jaccard, Samuel Laurent |
spellingShingle |
Amsler, Helen Eri Thöle, Lena Mareike Stimac, Ingrid Geibert, Walter Ikehara, Minoru Kuhn, Gerhard Esper, Oliver Jaccard, Samuel Laurent Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception |
author_facet |
Amsler, Helen Eri Thöle, Lena Mareike Stimac, Ingrid Geibert, Walter Ikehara, Minoru Kuhn, Gerhard Esper, Oliver Jaccard, Samuel Laurent |
author_sort |
Amsler, Helen Eri |
title |
Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception |
title_short |
Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception |
title_full |
Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception |
title_fullStr |
Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception |
title_full_unstemmed |
Bottom water oxygenation changes in the Southwestern Indian Ocean as an indicator for enhanced respired carbon storage since the last glacial inception |
title_sort |
bottom water oxygenation changes in the southwestern indian ocean as an indicator for enhanced respired carbon storage since the last glacial inception |
publishDate |
2021 |
url |
https://doi.org/10.5194/cp-2021-29 https://cp.copernicus.org/preprints/cp-2021-29/ |
geographic |
Antarctic Indian The Antarctic |
geographic_facet |
Antarctic Indian The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
eISSN: 1814-9332 |
op_relation |
doi:10.5194/cp-2021-29 https://cp.copernicus.org/preprints/cp-2021-29/ |
op_doi |
https://doi.org/10.5194/cp-2021-29 |
_version_ |
1766020116932198400 |