Centennial scale climate instabilities in a wet early Holocene West African monsoon
A Holocene Gulf of Guinea record of riverine runoff, based on Ba/Ca in tests of a shallow-dwelling planktic foraminifer, and sea surface temperature (SST), based on Mg/Ca, reveals centennial-scale instabilities in West African monsoon (WAM) precipitation and eastern equatorial Atlantic (EEA) thermal...
Published in: | Geophysical Research Letters |
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Language: | English |
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2007
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Online Access: | https://oceanrep.geomar.de/id/eprint/7649/ https://oceanrep.geomar.de/id/eprint/7649/1/2007GL031898.pdf https://doi.org/10.1029/2007GL031898 |
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ftoceanrep:oai:oceanrep.geomar.de:7649 2023-05-15T16:29:27+02:00 Centennial scale climate instabilities in a wet early Holocene West African monsoon Weldeab, Syee Lea, D. W. Schneider, Ralph Andersen, Nils 2007 text https://oceanrep.geomar.de/id/eprint/7649/ https://oceanrep.geomar.de/id/eprint/7649/1/2007GL031898.pdf https://doi.org/10.1029/2007GL031898 en eng AGU (American Geophysical Union) https://oceanrep.geomar.de/id/eprint/7649/1/2007GL031898.pdf Weldeab, S., Lea, D. W., Schneider, R. and Andersen, N. (2007) Centennial scale climate instabilities in a wet early Holocene West African monsoon. Open Access Geophysical Research Letters, 34 . L24702. DOI 10.1029/2007GL031898 <https://doi.org/10.1029/2007GL031898>. doi:10.1029/2007GL031898 info:eu-repo/semantics/openAccess Article PeerReviewed 2007 ftoceanrep https://doi.org/10.1029/2007GL031898 2023-04-07T14:55:10Z A Holocene Gulf of Guinea record of riverine runoff, based on Ba/Ca in tests of a shallow-dwelling planktic foraminifer, and sea surface temperature (SST), based on Mg/Ca, reveals centennial-scale instabilities in West African monsoon (WAM) precipitation and eastern equatorial Atlantic (EEA) thermal conditions. The long-term Holocene climate trend is characterized by a warm and wet early-mid Holocene and gradual drying and cooling during the late Holocene. Superimposed on this trend are numerous centennial scale drops in precipitation during the early-mid Holocene. The greatest declines in early Holocene monsoon precipitation were accompanied by significant SST cooling in the EEA and correlate with drops in air temperature over Greenland and fresh water outbursts into the North Atlantic (NA). This observation suggests that early Holocene climate instabilities in the NA were closely linked to changes in the WAM. The strong imprint of NA events in summer monsoon precipitation suggests that these events were not confined to winter-time. The late Holocene does not show large amplitude changes in riverine runoff at the centennial level. The relatively stable late Holocene conditions likely reflect a weakening and stabilization of the monsoon system, probably due to diminished influence of the NA region due to a reduction in ice sheet. Article in Journal/Newspaper Greenland Ice Sheet North Atlantic OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Greenland Geophysical Research Letters 34 24 |
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Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
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ftoceanrep |
language |
English |
description |
A Holocene Gulf of Guinea record of riverine runoff, based on Ba/Ca in tests of a shallow-dwelling planktic foraminifer, and sea surface temperature (SST), based on Mg/Ca, reveals centennial-scale instabilities in West African monsoon (WAM) precipitation and eastern equatorial Atlantic (EEA) thermal conditions. The long-term Holocene climate trend is characterized by a warm and wet early-mid Holocene and gradual drying and cooling during the late Holocene. Superimposed on this trend are numerous centennial scale drops in precipitation during the early-mid Holocene. The greatest declines in early Holocene monsoon precipitation were accompanied by significant SST cooling in the EEA and correlate with drops in air temperature over Greenland and fresh water outbursts into the North Atlantic (NA). This observation suggests that early Holocene climate instabilities in the NA were closely linked to changes in the WAM. The strong imprint of NA events in summer monsoon precipitation suggests that these events were not confined to winter-time. The late Holocene does not show large amplitude changes in riverine runoff at the centennial level. The relatively stable late Holocene conditions likely reflect a weakening and stabilization of the monsoon system, probably due to diminished influence of the NA region due to a reduction in ice sheet. |
format |
Article in Journal/Newspaper |
author |
Weldeab, Syee Lea, D. W. Schneider, Ralph Andersen, Nils |
spellingShingle |
Weldeab, Syee Lea, D. W. Schneider, Ralph Andersen, Nils Centennial scale climate instabilities in a wet early Holocene West African monsoon |
author_facet |
Weldeab, Syee Lea, D. W. Schneider, Ralph Andersen, Nils |
author_sort |
Weldeab, Syee |
title |
Centennial scale climate instabilities in a wet early Holocene West African monsoon |
title_short |
Centennial scale climate instabilities in a wet early Holocene West African monsoon |
title_full |
Centennial scale climate instabilities in a wet early Holocene West African monsoon |
title_fullStr |
Centennial scale climate instabilities in a wet early Holocene West African monsoon |
title_full_unstemmed |
Centennial scale climate instabilities in a wet early Holocene West African monsoon |
title_sort |
centennial scale climate instabilities in a wet early holocene west african monsoon |
publisher |
AGU (American Geophysical Union) |
publishDate |
2007 |
url |
https://oceanrep.geomar.de/id/eprint/7649/ https://oceanrep.geomar.de/id/eprint/7649/1/2007GL031898.pdf https://doi.org/10.1029/2007GL031898 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet North Atlantic |
genre_facet |
Greenland Ice Sheet North Atlantic |
op_relation |
https://oceanrep.geomar.de/id/eprint/7649/1/2007GL031898.pdf Weldeab, S., Lea, D. W., Schneider, R. and Andersen, N. (2007) Centennial scale climate instabilities in a wet early Holocene West African monsoon. Open Access Geophysical Research Letters, 34 . L24702. DOI 10.1029/2007GL031898 <https://doi.org/10.1029/2007GL031898>. doi:10.1029/2007GL031898 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2007GL031898 |
container_title |
Geophysical Research Letters |
container_volume |
34 |
container_issue |
24 |
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1766019149889273856 |