Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357
We present 230Th-normalized dust and export production fluxes for two contrasted marine sediment cores spanning the Antarctic Polar Front, close to the Kerguelen Plateau in the Southern Indian Ocean, covering the last glacial cycle. We report glacial lithogenic fluxes comparable to the South Atlanti...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.907130 2024-09-15T17:43:42+00:00 Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357 Thöle, Lena M Amsler, Helen Eri Moretti, Simone Auderset, Alexandra Gilgannon, James Lippold, Jörg Vogel, Hendrik Crosta, Xavier Mazaud, Alain Michel, Elisabeth Martínez-García, Alfredo Jaccard, Samuel L MEDIAN LATITUDE: -47.623500 * MEDIAN LONGITUDE: 74.407500 * SOUTH-BOUND LATITUDE: -50.567000 * WEST-BOUND LONGITUDE: 68.385000 * NORTH-BOUND LATITUDE: -44.680000 * EAST-BOUND LONGITUDE: 80.430000 * DATE/TIME START: 2011-01-30T00:00:00 * DATE/TIME END: 2011-02-08T00:00:00 2019 application/zip, 12 datasets https://doi.pangaea.de/10.1594/PANGAEA.907130 https://doi.org/10.1594/PANGAEA.907130 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.907130 https://doi.org/10.1594/PANGAEA.907130 CC-BY-4.0: Creative Commons Attribution 4.0 International Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Thöle, Lena M; Amsler, Helen Eri; Moretti, Simone; Auderset, Alexandra; Gilgannon, James; Lippold, Jörg; Vogel, Hendrik; Crosta, Xavier; Mazaud, Alain; Michel, Elisabeth; Martínez-García, Alfredo; Jaccard, Samuel L (2019): Glacial-interglacial dust and export production records from the Southern Indian Ocean. Earth and Planetary Science Letters, 525, 115716, https://doi.org/10.1016/j.epsl.2019.115716 Antarctic Zone glacial-interglacial changes iron fertilization Southern Ocean Subantarctic zone dataset publication series 2019 ftpangaea https://doi.org/10.1594/PANGAEA.90713010.1016/j.epsl.2019.115716 2024-07-24T02:31:21Z We present 230Th-normalized dust and export production fluxes for two contrasted marine sediment cores spanning the Antarctic Polar Front, close to the Kerguelen Plateau in the Southern Indian Ocean, covering the last glacial cycle. We report glacial lithogenic fluxes comparable to the South Atlantic and higher than in the South Pacific sectors of the Southern Ocean. Structural and temporal discrepancies with dust reconstructions from Antarctic ice cores and the Atlantic and Pacific sectors of the Subantarctic Zone (SAZ) point towards Southern Africa and/or the Kerguelen Plateau as an additional source of lithogenic material to the Southern Indian Ocean during the last ice age. In the SAZ, export production proxies respond to iron (Fe) fertilization with total organic carbon (TOC) fluxes as high as those previously reported from the Atlantic sector of the Southern Ocean. However, the correlation between export production and dust proxies is weaker than in the other sectors, and shows a muted response of export production during peak glacials. We hypothesize that this muted response may be related to macronutrient (co-)limitation imposed on phytoplankton growth possibly induced by a northward displacement of wind-driven upwelling and/or the polar frontal system during peak glacials. The Antarctic Zone (AZ) record depicts the typical pattern of enhanced export production during interglacials and comparatively low productivity during glacials suggesting a decrease in the supply of macronutrients to the AZ surface during ice ages compared to warm periods, as previously proposed. However, a muted response of opal fluxes during marine isotope stage (MIS) 5e argues for a southward migration of the frontal system during warmer MIS 5e, possibly causing silicic acid (co-)limitation at this site. These results illustrate the important role of Fe fertilization and changes in wind-driven upwelling intensities in modulating the strength and efficiency of the biological carbon pump in the Southern Ocean, but also highlight the ... Other/Unknown Material Antarc* Antarctic Southern Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(68.385000,80.430000,-44.680000,-50.567000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
Antarctic Zone glacial-interglacial changes iron fertilization Southern Ocean Subantarctic zone |
spellingShingle |
Antarctic Zone glacial-interglacial changes iron fertilization Southern Ocean Subantarctic zone Thöle, Lena M Amsler, Helen Eri Moretti, Simone Auderset, Alexandra Gilgannon, James Lippold, Jörg Vogel, Hendrik Crosta, Xavier Mazaud, Alain Michel, Elisabeth Martínez-García, Alfredo Jaccard, Samuel L Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357 |
topic_facet |
Antarctic Zone glacial-interglacial changes iron fertilization Southern Ocean Subantarctic zone |
description |
We present 230Th-normalized dust and export production fluxes for two contrasted marine sediment cores spanning the Antarctic Polar Front, close to the Kerguelen Plateau in the Southern Indian Ocean, covering the last glacial cycle. We report glacial lithogenic fluxes comparable to the South Atlantic and higher than in the South Pacific sectors of the Southern Ocean. Structural and temporal discrepancies with dust reconstructions from Antarctic ice cores and the Atlantic and Pacific sectors of the Subantarctic Zone (SAZ) point towards Southern Africa and/or the Kerguelen Plateau as an additional source of lithogenic material to the Southern Indian Ocean during the last ice age. In the SAZ, export production proxies respond to iron (Fe) fertilization with total organic carbon (TOC) fluxes as high as those previously reported from the Atlantic sector of the Southern Ocean. However, the correlation between export production and dust proxies is weaker than in the other sectors, and shows a muted response of export production during peak glacials. We hypothesize that this muted response may be related to macronutrient (co-)limitation imposed on phytoplankton growth possibly induced by a northward displacement of wind-driven upwelling and/or the polar frontal system during peak glacials. The Antarctic Zone (AZ) record depicts the typical pattern of enhanced export production during interglacials and comparatively low productivity during glacials suggesting a decrease in the supply of macronutrients to the AZ surface during ice ages compared to warm periods, as previously proposed. However, a muted response of opal fluxes during marine isotope stage (MIS) 5e argues for a southward migration of the frontal system during warmer MIS 5e, possibly causing silicic acid (co-)limitation at this site. These results illustrate the important role of Fe fertilization and changes in wind-driven upwelling intensities in modulating the strength and efficiency of the biological carbon pump in the Southern Ocean, but also highlight the ... |
format |
Other/Unknown Material |
author |
Thöle, Lena M Amsler, Helen Eri Moretti, Simone Auderset, Alexandra Gilgannon, James Lippold, Jörg Vogel, Hendrik Crosta, Xavier Mazaud, Alain Michel, Elisabeth Martínez-García, Alfredo Jaccard, Samuel L |
author_facet |
Thöle, Lena M Amsler, Helen Eri Moretti, Simone Auderset, Alexandra Gilgannon, James Lippold, Jörg Vogel, Hendrik Crosta, Xavier Mazaud, Alain Michel, Elisabeth Martínez-García, Alfredo Jaccard, Samuel L |
author_sort |
Thöle, Lena M |
title |
Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357 |
title_short |
Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357 |
title_full |
Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357 |
title_fullStr |
Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357 |
title_full_unstemmed |
Concentration and fluxes of dust and export production proxies on cores MD11-3353 and MD11-3357 |
title_sort |
concentration and fluxes of dust and export production proxies on cores md11-3353 and md11-3357 |
publisher |
PANGAEA |
publishDate |
2019 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.907130 https://doi.org/10.1594/PANGAEA.907130 |
op_coverage |
MEDIAN LATITUDE: -47.623500 * MEDIAN LONGITUDE: 74.407500 * SOUTH-BOUND LATITUDE: -50.567000 * WEST-BOUND LONGITUDE: 68.385000 * NORTH-BOUND LATITUDE: -44.680000 * EAST-BOUND LONGITUDE: 80.430000 * DATE/TIME START: 2011-01-30T00:00:00 * DATE/TIME END: 2011-02-08T00:00:00 |
long_lat |
ENVELOPE(68.385000,80.430000,-44.680000,-50.567000) |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_source |
Supplement to: Thöle, Lena M; Amsler, Helen Eri; Moretti, Simone; Auderset, Alexandra; Gilgannon, James; Lippold, Jörg; Vogel, Hendrik; Crosta, Xavier; Mazaud, Alain; Michel, Elisabeth; Martínez-García, Alfredo; Jaccard, Samuel L (2019): Glacial-interglacial dust and export production records from the Southern Indian Ocean. Earth and Planetary Science Letters, 525, 115716, https://doi.org/10.1016/j.epsl.2019.115716 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.907130 https://doi.org/10.1594/PANGAEA.907130 |
op_rights |
CC-BY-4.0: Creative Commons Attribution 4.0 International Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.90713010.1016/j.epsl.2019.115716 |
_version_ |
1810490813887545344 |