Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 19 (2004): PA2018, doi:10.1029/2003PA000986. The eastern equatorial Pacific (...
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Language: | English |
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Online Access: | https://hdl.handle.net/1912/3428 |
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ftwhoas:oai:darchive.mblwhoilibrary.org:1912/3428 2023-05-15T18:25:47+02:00 Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present Loubere, Paul Mekik, Figen Francois, Roger Pichat, Sylvain 2004-06-12 application/pdf https://hdl.handle.net/1912/3428 en_US eng American Geophysical Union https://doi.org/10.1029/2003PA000986 Paleoceanography 19 (2004): PA2018 https://hdl.handle.net/1912/3428 doi:10.1029/2003PA000986 Paleoceanography 19 (2004): PA2018 doi:10.1029/2003PA000986 Calcite fluxes Eastern equatorial Pacific Glacial-interglacial Article 2004 ftwhoas https://doi.org/10.1029/2003PA000986 2022-05-28T22:57:58Z Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 19 (2004): PA2018, doi:10.1029/2003PA000986. The eastern equatorial Pacific (EEP) is an important center of biological productivity, generating significant organic carbon and calcite fluxes to the deep ocean. We reconstructed paleocalcite flux for the past 30,000 years in four cores collected beneath the equatorial upwelling and the South Equatorial Current (SEC) by measuring ex230Th-normalized calcite accumulation rates corrected for dissolution with a newly developed proxy for “fraction of calcite preserved.” This method produced very similar results at the four sites and revealed that the export flux of calcite was 30–50% lower during the LGM compared to the Holocene. The internal consistency of these results supports our interpretation, which is also in agreement with emerging data indicating lower glacial productivity in the EEP, possibly as a result of lower nutrient supply from the southern ocean via the Equatorial Undercurrent. However, these findings contradict previous interpretations based on mass accumulation rates (MAR) of biogenic material in the sediment of the EEP, which have been taken as reflecting higher glacial productivity due to stronger wind-driven upwelling. This research was partly supported by NSF grant OCE-0095617 and funds from the Northern Illinois University Graduate School (Loubere); the NASA Michigan Space Grant Consortium Seed Grant for summer, 2001 for 230Th analyses at WHOI (Mekik); the French Ministere de l’Education Nationale, de la Recherche et de la Technologie, and a EURODOC grant from the Region Rhone-Alpes (Pichat). Article in Journal/Newspaper Southern Ocean Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Pacific Rhone ENVELOPE(158.733,158.733,-79.983,-79.983) Southern Ocean Paleoceanography 19 2 n/a n/a |
institution |
Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
op_collection_id |
ftwhoas |
language |
English |
topic |
Calcite fluxes Eastern equatorial Pacific Glacial-interglacial |
spellingShingle |
Calcite fluxes Eastern equatorial Pacific Glacial-interglacial Loubere, Paul Mekik, Figen Francois, Roger Pichat, Sylvain Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present |
topic_facet |
Calcite fluxes Eastern equatorial Pacific Glacial-interglacial |
description |
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 19 (2004): PA2018, doi:10.1029/2003PA000986. The eastern equatorial Pacific (EEP) is an important center of biological productivity, generating significant organic carbon and calcite fluxes to the deep ocean. We reconstructed paleocalcite flux for the past 30,000 years in four cores collected beneath the equatorial upwelling and the South Equatorial Current (SEC) by measuring ex230Th-normalized calcite accumulation rates corrected for dissolution with a newly developed proxy for “fraction of calcite preserved.” This method produced very similar results at the four sites and revealed that the export flux of calcite was 30–50% lower during the LGM compared to the Holocene. The internal consistency of these results supports our interpretation, which is also in agreement with emerging data indicating lower glacial productivity in the EEP, possibly as a result of lower nutrient supply from the southern ocean via the Equatorial Undercurrent. However, these findings contradict previous interpretations based on mass accumulation rates (MAR) of biogenic material in the sediment of the EEP, which have been taken as reflecting higher glacial productivity due to stronger wind-driven upwelling. This research was partly supported by NSF grant OCE-0095617 and funds from the Northern Illinois University Graduate School (Loubere); the NASA Michigan Space Grant Consortium Seed Grant for summer, 2001 for 230Th analyses at WHOI (Mekik); the French Ministere de l’Education Nationale, de la Recherche et de la Technologie, and a EURODOC grant from the Region Rhone-Alpes (Pichat). |
format |
Article in Journal/Newspaper |
author |
Loubere, Paul Mekik, Figen Francois, Roger Pichat, Sylvain |
author_facet |
Loubere, Paul Mekik, Figen Francois, Roger Pichat, Sylvain |
author_sort |
Loubere, Paul |
title |
Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present |
title_short |
Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present |
title_full |
Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present |
title_fullStr |
Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present |
title_full_unstemmed |
Export fluxes of calcite in the eastern equatorial Pacific from the Last Glacial Maximum to present |
title_sort |
export fluxes of calcite in the eastern equatorial pacific from the last glacial maximum to present |
publisher |
American Geophysical Union |
publishDate |
2004 |
url |
https://hdl.handle.net/1912/3428 |
long_lat |
ENVELOPE(158.733,158.733,-79.983,-79.983) |
geographic |
Pacific Rhone Southern Ocean |
geographic_facet |
Pacific Rhone Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Paleoceanography 19 (2004): PA2018 doi:10.1029/2003PA000986 |
op_relation |
https://doi.org/10.1029/2003PA000986 Paleoceanography 19 (2004): PA2018 https://hdl.handle.net/1912/3428 doi:10.1029/2003PA000986 |
op_doi |
https://doi.org/10.1029/2003PA000986 |
container_title |
Paleoceanography |
container_volume |
19 |
container_issue |
2 |
container_start_page |
n/a |
op_container_end_page |
n/a |
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1766207445996142592 |