Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean
International audience Oceanic nutrient cycling in the Southern Ocean is supposed to have an important impact on glacial-interglacial atmospheric CO 2 changes and global climate. In order to characterize such nutrient cycling over the last two climatic cycles we investigated carbon and nitrogen isot...
Published in: | Paleoceanography |
---|---|
Main Authors: | , |
Other Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2002
|
Subjects: | |
Online Access: | https://hal.archives-ouvertes.fr/hal-02105706 https://hal.archives-ouvertes.fr/hal-02105706/document https://hal.archives-ouvertes.fr/hal-02105706/file/Crosta_Paleocean2002.pdf https://doi.org/10.1029/2000PA000565 |
id |
ftccsdartic:oai:HAL:hal-02105706v1 |
---|---|
record_format |
openpolar |
spelling |
ftccsdartic:oai:HAL:hal-02105706v1 2023-05-15T14:03:01+02:00 Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean Crosta, Xavier Shemesh, A. Environnements et Paléoenvironnements OCéaniques (EPOC) Observatoire aquitain des sciences de l'univers (OASU) Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) Department of Earth and Planetary Science Rehovot Weizmann Institute of Science Rehovot, Israël 2002 https://hal.archives-ouvertes.fr/hal-02105706 https://hal.archives-ouvertes.fr/hal-02105706/document https://hal.archives-ouvertes.fr/hal-02105706/file/Crosta_Paleocean2002.pdf https://doi.org/10.1029/2000PA000565 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2000PA000565 hal-02105706 https://hal.archives-ouvertes.fr/hal-02105706 https://hal.archives-ouvertes.fr/hal-02105706/document https://hal.archives-ouvertes.fr/hal-02105706/file/Crosta_Paleocean2002.pdf doi:10.1029/2000PA000565 info:eu-repo/semantics/OpenAccess ISSN: 0883-8305 Paleoceanography https://hal.archives-ouvertes.fr/hal-02105706 Paleoceanography, American Geophysical Union, 2002, 17 (1), pp.10-1-10-8. ⟨10.1029/2000PA000565⟩ geochemistry diatoms Southern Ocean paleoceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology info:eu-repo/semantics/article Journal articles 2002 ftccsdartic https://doi.org/10.1029/2000PA000565 2021-11-21T01:31:59Z International audience Oceanic nutrient cycling in the Southern Ocean is supposed to have an important impact on glacial-interglacial atmospheric CO 2 changes and global climate. In order to characterize such nutrient cycling over the last two climatic cycles we investigated carbon and nitrogen isotopic ratios of diatom-bound organic matter (d 13 C diat and d 15 N diat , respectively) in two cores retrieved form the Atlantic and Indian sectors of the Antarctic Ocean. The two cores show the same isotopic patterns. The d 13 C diat values are depleted during glacial periods and enriched during interglacial periods, indicating lower productivity during cold times. The d 15 N diat values are enriched during glacial periods and depleted during interglacial periods, arguing for greater nitrate utilization during cold times. Taken at face value, this apparent contradiction leads to opposite conclusions on the role of the Southern Ocean biological pump on the atmospheric CO 2 changes. However, the two sets of data can be reconciled by a ''sea ice plus mixing rate scenario'' that calls upon a balance between the effect of cutting off gas transfer at the ocean-atmosphere boundary and the effect of reducing vertical transport of nutrients through the pycnocline. Article in Journal/Newspaper Antarc* Antarctic Antarctic Ocean Sea ice Southern Ocean Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Antarctic Southern Ocean The Antarctic Indian Antarctic Ocean Paleoceanography 17 1 10-1 10-8 |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
geochemistry diatoms Southern Ocean paleoceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology |
spellingShingle |
geochemistry diatoms Southern Ocean paleoceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology Crosta, Xavier Shemesh, A. Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean |
topic_facet |
geochemistry diatoms Southern Ocean paleoceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology |
description |
International audience Oceanic nutrient cycling in the Southern Ocean is supposed to have an important impact on glacial-interglacial atmospheric CO 2 changes and global climate. In order to characterize such nutrient cycling over the last two climatic cycles we investigated carbon and nitrogen isotopic ratios of diatom-bound organic matter (d 13 C diat and d 15 N diat , respectively) in two cores retrieved form the Atlantic and Indian sectors of the Antarctic Ocean. The two cores show the same isotopic patterns. The d 13 C diat values are depleted during glacial periods and enriched during interglacial periods, indicating lower productivity during cold times. The d 15 N diat values are enriched during glacial periods and depleted during interglacial periods, arguing for greater nitrate utilization during cold times. Taken at face value, this apparent contradiction leads to opposite conclusions on the role of the Southern Ocean biological pump on the atmospheric CO 2 changes. However, the two sets of data can be reconciled by a ''sea ice plus mixing rate scenario'' that calls upon a balance between the effect of cutting off gas transfer at the ocean-atmosphere boundary and the effect of reducing vertical transport of nutrients through the pycnocline. |
author2 |
Environnements et Paléoenvironnements OCéaniques (EPOC) Observatoire aquitain des sciences de l'univers (OASU) Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) Department of Earth and Planetary Science Rehovot Weizmann Institute of Science Rehovot, Israël |
format |
Article in Journal/Newspaper |
author |
Crosta, Xavier Shemesh, A. |
author_facet |
Crosta, Xavier Shemesh, A. |
author_sort |
Crosta, Xavier |
title |
Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean |
title_short |
Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean |
title_full |
Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean |
title_fullStr |
Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean |
title_full_unstemmed |
Reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the Southern Ocean |
title_sort |
reconciling down core anticorrelation of diatom carbon and nitrogen isotopic ratios from the southern ocean |
publisher |
HAL CCSD |
publishDate |
2002 |
url |
https://hal.archives-ouvertes.fr/hal-02105706 https://hal.archives-ouvertes.fr/hal-02105706/document https://hal.archives-ouvertes.fr/hal-02105706/file/Crosta_Paleocean2002.pdf https://doi.org/10.1029/2000PA000565 |
geographic |
Antarctic Southern Ocean The Antarctic Indian Antarctic Ocean |
geographic_facet |
Antarctic Southern Ocean The Antarctic Indian Antarctic Ocean |
genre |
Antarc* Antarctic Antarctic Ocean Sea ice Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Ocean Sea ice Southern Ocean |
op_source |
ISSN: 0883-8305 Paleoceanography https://hal.archives-ouvertes.fr/hal-02105706 Paleoceanography, American Geophysical Union, 2002, 17 (1), pp.10-1-10-8. ⟨10.1029/2000PA000565⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2000PA000565 hal-02105706 https://hal.archives-ouvertes.fr/hal-02105706 https://hal.archives-ouvertes.fr/hal-02105706/document https://hal.archives-ouvertes.fr/hal-02105706/file/Crosta_Paleocean2002.pdf doi:10.1029/2000PA000565 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2000PA000565 |
container_title |
Paleoceanography |
container_volume |
17 |
container_issue |
1 |
container_start_page |
10-1 |
op_container_end_page |
10-8 |
_version_ |
1766273471711543296 |