Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr
Thanks to its optimal location on the northern Brazilian margin, core MD09-3257 records both ocean circulation and atmospheric changes. The latter occur locally in the form of increased rainfall on the adjacent continent during the cold intervals recorded in Greenland ice and northern North Atlantic...
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Language: | English |
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Copernicus Gesellschaft Mbh
2018
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Online Access: | https://archimer.ifremer.fr/doc/00460/57126/59040.pdf https://archimer.ifremer.fr/doc/00460/57126/59041.pdf http://archimer.ifremer.fr/doc/00460/57126/59043.xlsx https://archimer.ifremer.fr/doc/00460/57126/59044.pdf https://archimer.ifremer.fr/doc/00460/57126/59045.pdf http://archimer.ifremer.fr/doc/00460/57126/59046.xlsx https://archimer.ifremer.fr/doc/00460/57126/59047.pdf https://doi.org/10.5194/cp-14-1315-2018 https://archimer.ifremer.fr/doc/00460/57126/ |
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ftarchimer:oai:archimer.ifremer.fr:57126 2023-05-15T16:27:22+02:00 Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr Waelbroeck, Claire Pichat, Sylvain Bohm, Evelyn Lougheed, Bryan C. Faranda, Davide Vrac, Mathieu Missiaen, Lise Vazquez Riveiros, Natalia Burckel, Pierre Lippold, Joerg Arz, Helge W. Dokken, Trond Thil, Francois Dapoigny, Arnaud 2018-09 application/pdf https://archimer.ifremer.fr/doc/00460/57126/59040.pdf https://archimer.ifremer.fr/doc/00460/57126/59041.pdf http://archimer.ifremer.fr/doc/00460/57126/59043.xlsx https://archimer.ifremer.fr/doc/00460/57126/59044.pdf https://archimer.ifremer.fr/doc/00460/57126/59045.pdf http://archimer.ifremer.fr/doc/00460/57126/59046.xlsx https://archimer.ifremer.fr/doc/00460/57126/59047.pdf https://doi.org/10.5194/cp-14-1315-2018 https://archimer.ifremer.fr/doc/00460/57126/ eng eng Copernicus Gesellschaft Mbh info:eu-repo/grantAgreement/EC/FP7/339108/EU//ACCLIMATE https://archimer.ifremer.fr/doc/00460/57126/59040.pdf https://archimer.ifremer.fr/doc/00460/57126/59041.pdf http://archimer.ifremer.fr/doc/00460/57126/59043.xlsx https://archimer.ifremer.fr/doc/00460/57126/59044.pdf https://archimer.ifremer.fr/doc/00460/57126/59045.pdf http://archimer.ifremer.fr/doc/00460/57126/59046.xlsx https://archimer.ifremer.fr/doc/00460/57126/59047.pdf doi:10.5194/cp-14-1315-2018 https://archimer.ifremer.fr/doc/00460/57126/ Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. info:eu-repo/semantics/openAccess restricted use CC-BY Climate Of The Past (1814-9324) (Copernicus Gesellschaft Mbh), 2018-09 , Vol. 14 , N. 9 , P. 1315-1330 text Publication info:eu-repo/semantics/article 2018 ftarchimer https://doi.org/10.5194/cp-14-1315-2018 2021-09-23T20:31:38Z Thanks to its optimal location on the northern Brazilian margin, core MD09-3257 records both ocean circulation and atmospheric changes. The latter occur locally in the form of increased rainfall on the adjacent continent during the cold intervals recorded in Greenland ice and northern North Atlantic sediment cores (i.e., Greenland stadials). These rainfall events are recorded in MD09-3257 as peaks in ln(Ti / Ca). New sedimentary Pa / Th data indicate that mid-depth western equatorial water mass transport decreased during all of the Greenland stadials of the last 40 kyr. Using cross-wavelet transforms and spectrogram analysis, we assess the relative phase between the MD09-3257 sedimentary Pa / Th and ln(Ti/Ca) signals. We show that decreased water mass transport between a depth of similar to 1300 and 2300 m in the western equatorial Atlantic preceded increased rainfall over the adjacent continent by 120 to 400 yr at Dansgaard-Oeschger (D-O) frequencies, and by 280 to 980 yr at Heinrich-like frequencies. We suggest that the large lead of ocean circulation changes with respect to changes in tropical South American precipitation at Heinrich-like frequencies is related to the effect of a positive feedback involving iceberg discharges in the North Atlantic. In contrast, the absence of widespread ice rafted detrital layers in North Atlantic cores during D-O stadials supports the hypothesis that a feedback such as this was not triggered in the case of D-O stadials, with circulation slowdowns and subsequent changes remaining more limited during D-O stadials than Heinrich stadials. Article in Journal/Newspaper Greenland North Atlantic Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Greenland Climate of the Past 14 9 1315 1330 |
institution |
Open Polar |
collection |
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) |
op_collection_id |
ftarchimer |
language |
English |
description |
Thanks to its optimal location on the northern Brazilian margin, core MD09-3257 records both ocean circulation and atmospheric changes. The latter occur locally in the form of increased rainfall on the adjacent continent during the cold intervals recorded in Greenland ice and northern North Atlantic sediment cores (i.e., Greenland stadials). These rainfall events are recorded in MD09-3257 as peaks in ln(Ti / Ca). New sedimentary Pa / Th data indicate that mid-depth western equatorial water mass transport decreased during all of the Greenland stadials of the last 40 kyr. Using cross-wavelet transforms and spectrogram analysis, we assess the relative phase between the MD09-3257 sedimentary Pa / Th and ln(Ti/Ca) signals. We show that decreased water mass transport between a depth of similar to 1300 and 2300 m in the western equatorial Atlantic preceded increased rainfall over the adjacent continent by 120 to 400 yr at Dansgaard-Oeschger (D-O) frequencies, and by 280 to 980 yr at Heinrich-like frequencies. We suggest that the large lead of ocean circulation changes with respect to changes in tropical South American precipitation at Heinrich-like frequencies is related to the effect of a positive feedback involving iceberg discharges in the North Atlantic. In contrast, the absence of widespread ice rafted detrital layers in North Atlantic cores during D-O stadials supports the hypothesis that a feedback such as this was not triggered in the case of D-O stadials, with circulation slowdowns and subsequent changes remaining more limited during D-O stadials than Heinrich stadials. |
format |
Article in Journal/Newspaper |
author |
Waelbroeck, Claire Pichat, Sylvain Bohm, Evelyn Lougheed, Bryan C. Faranda, Davide Vrac, Mathieu Missiaen, Lise Vazquez Riveiros, Natalia Burckel, Pierre Lippold, Joerg Arz, Helge W. Dokken, Trond Thil, Francois Dapoigny, Arnaud |
spellingShingle |
Waelbroeck, Claire Pichat, Sylvain Bohm, Evelyn Lougheed, Bryan C. Faranda, Davide Vrac, Mathieu Missiaen, Lise Vazquez Riveiros, Natalia Burckel, Pierre Lippold, Joerg Arz, Helge W. Dokken, Trond Thil, Francois Dapoigny, Arnaud Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr |
author_facet |
Waelbroeck, Claire Pichat, Sylvain Bohm, Evelyn Lougheed, Bryan C. Faranda, Davide Vrac, Mathieu Missiaen, Lise Vazquez Riveiros, Natalia Burckel, Pierre Lippold, Joerg Arz, Helge W. Dokken, Trond Thil, Francois Dapoigny, Arnaud |
author_sort |
Waelbroeck, Claire |
title |
Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr |
title_short |
Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr |
title_full |
Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr |
title_fullStr |
Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr |
title_full_unstemmed |
Rbiative timing of precipitation and ocean circui In changes in the western equatorial Atlantic over the last 45 kyr |
title_sort |
rbiative timing of precipitation and ocean circui in changes in the western equatorial atlantic over the last 45 kyr |
publisher |
Copernicus Gesellschaft Mbh |
publishDate |
2018 |
url |
https://archimer.ifremer.fr/doc/00460/57126/59040.pdf https://archimer.ifremer.fr/doc/00460/57126/59041.pdf http://archimer.ifremer.fr/doc/00460/57126/59043.xlsx https://archimer.ifremer.fr/doc/00460/57126/59044.pdf https://archimer.ifremer.fr/doc/00460/57126/59045.pdf http://archimer.ifremer.fr/doc/00460/57126/59046.xlsx https://archimer.ifremer.fr/doc/00460/57126/59047.pdf https://doi.org/10.5194/cp-14-1315-2018 https://archimer.ifremer.fr/doc/00460/57126/ |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland North Atlantic |
genre_facet |
Greenland North Atlantic |
op_source |
Climate Of The Past (1814-9324) (Copernicus Gesellschaft Mbh), 2018-09 , Vol. 14 , N. 9 , P. 1315-1330 |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/339108/EU//ACCLIMATE https://archimer.ifremer.fr/doc/00460/57126/59040.pdf https://archimer.ifremer.fr/doc/00460/57126/59041.pdf http://archimer.ifremer.fr/doc/00460/57126/59043.xlsx https://archimer.ifremer.fr/doc/00460/57126/59044.pdf https://archimer.ifremer.fr/doc/00460/57126/59045.pdf http://archimer.ifremer.fr/doc/00460/57126/59046.xlsx https://archimer.ifremer.fr/doc/00460/57126/59047.pdf doi:10.5194/cp-14-1315-2018 https://archimer.ifremer.fr/doc/00460/57126/ |
op_rights |
Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. info:eu-repo/semantics/openAccess restricted use |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/cp-14-1315-2018 |
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Climate of the Past |
container_volume |
14 |
container_issue |
9 |
container_start_page |
1315 |
op_container_end_page |
1330 |
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1766016524165840896 |