Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2
International audience A detailed record of benthic foraminifera carbon isotopes from the South East Atlantic margin shows little glacial-interglacial variability between MIS-12 to MIS-10, suggesting that Glacial North Atlantic Intermediate Water (GNAIW) consistently penetrated to at least 30° S. Mi...
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ftinsu:oai:HAL:hal-00298224v1 2023-11-12T04:21:31+01:00 Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2 Dickson, A. J. Leng, M. J. Maslin, M. A. Environmental Change Research Centre Department of geography NERC Isotope Geosciences Laboratory British Geological Survey (BGS) 2008-06-05 https://hal.science/hal-00298224 https://hal.science/hal-00298224/document https://hal.science/hal-00298224/file/cpd-4-667-2008.pdf en eng HAL CCSD European Geosciences Union (EGU) hal-00298224 https://hal.science/hal-00298224 https://hal.science/hal-00298224/document https://hal.science/hal-00298224/file/cpd-4-667-2008.pdf info:eu-repo/semantics/OpenAccess ISSN: 1814-9340 EISSN: 1814-9359 Climate of the Past Discussions https://hal.science/hal-00298224 Climate of the Past Discussions, 2008, 4 (3), pp.667-695 [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2008 ftinsu 2023-10-25T16:28:11Z International audience A detailed record of benthic foraminifera carbon isotopes from the South East Atlantic margin shows little glacial-interglacial variability between MIS-12 to MIS-10, suggesting that Glacial North Atlantic Intermediate Water (GNAIW) consistently penetrated to at least 30° S. Millennial-scale increases in either the mass or flux of GNAIW over the core site occur alongside reductions in Lower North Atlantic Deep Water recorded in North Atlantic sediment cores and show that the lower and intermediate limb of the Atlantic deepwater convective cell oscillated in anti-phase during previous glacial periods. In addition, a 500 yr resolution record of the Cape Basin intermediate-deep ? 13 C gradient shows that a reduction in deep Southern Ocean ventilation at the end of MIS-11 was consistent with a modelled CO 2 drawdown of ~21?30 ppm. Further increases in the Southern Ocean chemical divide during the transition into MIS-10 were completed before minimum CO 2 levels were reached, suggesting that other mechanisms such as alkalinity changes were responsible for the remaining ~45 ppm drawdown. Article in Journal/Newspaper North Atlantic Deep Water North Atlantic South Atlantic Ocean Southern Ocean Institut national des sciences de l'Univers: HAL-INSU Southern Ocean |
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Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Dickson, A. J. Leng, M. J. Maslin, M. A. Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2 |
topic_facet |
[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience A detailed record of benthic foraminifera carbon isotopes from the South East Atlantic margin shows little glacial-interglacial variability between MIS-12 to MIS-10, suggesting that Glacial North Atlantic Intermediate Water (GNAIW) consistently penetrated to at least 30° S. Millennial-scale increases in either the mass or flux of GNAIW over the core site occur alongside reductions in Lower North Atlantic Deep Water recorded in North Atlantic sediment cores and show that the lower and intermediate limb of the Atlantic deepwater convective cell oscillated in anti-phase during previous glacial periods. In addition, a 500 yr resolution record of the Cape Basin intermediate-deep ? 13 C gradient shows that a reduction in deep Southern Ocean ventilation at the end of MIS-11 was consistent with a modelled CO 2 drawdown of ~21?30 ppm. Further increases in the Southern Ocean chemical divide during the transition into MIS-10 were completed before minimum CO 2 levels were reached, suggesting that other mechanisms such as alkalinity changes were responsible for the remaining ~45 ppm drawdown. |
author2 |
Environmental Change Research Centre Department of geography NERC Isotope Geosciences Laboratory British Geological Survey (BGS) |
format |
Article in Journal/Newspaper |
author |
Dickson, A. J. Leng, M. J. Maslin, M. A. |
author_facet |
Dickson, A. J. Leng, M. J. Maslin, M. A. |
author_sort |
Dickson, A. J. |
title |
Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2 |
title_short |
Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2 |
title_full |
Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2 |
title_fullStr |
Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2 |
title_full_unstemmed |
Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2 |
title_sort |
mid-depth south atlantic ocean circulation and chemical stratification during mis-10 to 12: implications for atmospheric co 2 |
publisher |
HAL CCSD |
publishDate |
2008 |
url |
https://hal.science/hal-00298224 https://hal.science/hal-00298224/document https://hal.science/hal-00298224/file/cpd-4-667-2008.pdf |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
North Atlantic Deep Water North Atlantic South Atlantic Ocean Southern Ocean |
genre_facet |
North Atlantic Deep Water North Atlantic South Atlantic Ocean Southern Ocean |
op_source |
ISSN: 1814-9340 EISSN: 1814-9359 Climate of the Past Discussions https://hal.science/hal-00298224 Climate of the Past Discussions, 2008, 4 (3), pp.667-695 |
op_relation |
hal-00298224 https://hal.science/hal-00298224 https://hal.science/hal-00298224/document https://hal.science/hal-00298224/file/cpd-4-667-2008.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782336884975861760 |