Mid-depth South Atlantic Ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO 2
A detailed record of benthic foraminifera carbon isotopes from the intermediate-depth South East Atlantic margin shows little glacial-interglacial variability between MIS-12 to MIS-10, suggesting that Northern Atlantic deepwaters consistently penetrated to at least 30° S. Millennial-scale increases...
Published in: | Climate of the Past |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
2008
|
Subjects: | |
Online Access: | https://oro.open.ac.uk/27671/ https://oro.open.ac.uk/27671/1/cp-4-333-2008.pdf https://doi.org/10.5194/cp-4-333-2008 |
id |
ftopenunivgb:oai:oro.open.ac.uk:27671 |
---|---|
record_format |
openpolar |
spelling |
ftopenunivgb:oai:oro.open.ac.uk:27671 2023-06-11T04:14:15+02:00 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. 2008 application/pdf https://oro.open.ac.uk/27671/ https://oro.open.ac.uk/27671/1/cp-4-333-2008.pdf https://doi.org/10.5194/cp-4-333-2008 unknown https://oro.open.ac.uk/27671/1/cp-4-333-2008.pdf Dickson, A. J. <http://oro.open.ac.uk/view/person/ad6596.html>; Leng, M. J. and Maslin, M. A. (2008). Mid-depth South Atlantic Ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO2. Climate of the Past, 4(4) pp. 333–344. Journal Item Public PeerReviewed 2008 ftopenunivgb https://doi.org/10.5194/cp-4-333-2008 2023-05-28T05:46:11Z A detailed record of benthic foraminifera carbon isotopes from the intermediate-depth South East Atlantic margin shows little glacial-interglacial variability between MIS-12 to MIS-10, suggesting that Northern Atlantic deepwaters consistently penetrated to at least 30° S. Millennial-scale increases in either the mass or flux of northern-sourced deepwaters over the core site occurred 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 δ 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 The Open University: Open Research Online (ORO) Southern Ocean Climate of the Past 4 4 333 344 |
institution |
Open Polar |
collection |
The Open University: Open Research Online (ORO) |
op_collection_id |
ftopenunivgb |
language |
unknown |
description |
A detailed record of benthic foraminifera carbon isotopes from the intermediate-depth South East Atlantic margin shows little glacial-interglacial variability between MIS-12 to MIS-10, suggesting that Northern Atlantic deepwaters consistently penetrated to at least 30° S. Millennial-scale increases in either the mass or flux of northern-sourced deepwaters over the core site occurred 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 δ 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. |
format |
Article in Journal/Newspaper |
author |
Dickson, A. J. Leng, M. J. Maslin, M. A. |
spellingShingle |
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 |
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 |
publishDate |
2008 |
url |
https://oro.open.ac.uk/27671/ https://oro.open.ac.uk/27671/1/cp-4-333-2008.pdf https://doi.org/10.5194/cp-4-333-2008 |
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_relation |
https://oro.open.ac.uk/27671/1/cp-4-333-2008.pdf Dickson, A. J. <http://oro.open.ac.uk/view/person/ad6596.html>; Leng, M. J. and Maslin, M. A. (2008). Mid-depth South Atlantic Ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO2. Climate of the Past, 4(4) pp. 333–344. |
op_doi |
https://doi.org/10.5194/cp-4-333-2008 |
container_title |
Climate of the Past |
container_volume |
4 |
container_issue |
4 |
container_start_page |
333 |
op_container_end_page |
344 |
_version_ |
1768392125689364480 |