Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean
Iron (Fe) is a key element in the Earth climate system, as it can enhance marine primary productivity in the high-nutrient low-chlorophyll (HNLC) regions where, despite a high concentration of major nutrients, chlorophyll production is low due to iron limitation. Eolian mineral dust represents one o...
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ftcopernicus:oai:publications.copernicus.org:cp86076 2023-05-15T15:14:08+02:00 Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean Burgay, François Spolaor, Andrea Gabrieli, Jacopo Cozzi, Giulio Turetta, Clara Vallelonga, Paul Barbante, Carlo 2021-02-23 info:eu-repo/semantics/application/pdf https://doi.org/10.5194/cp-17-491-2021 https://cp.copernicus.org/articles/17/491/2021/ eng eng info:eu-repo/grantAgreement/EC/FP7/243908 doi:10.5194/cp-17-491-2021 https://cp.copernicus.org/articles/17/491/2021/ info:eu-repo/semantics/openAccess eISSN: 1814-9332 info:eu-repo/semantics/Text 2021 ftcopernicus https://doi.org/10.5194/cp-17-491-2021 2021-03-01T17:22:15Z Iron (Fe) is a key element in the Earth climate system, as it can enhance marine primary productivity in the high-nutrient low-chlorophyll (HNLC) regions where, despite a high concentration of major nutrients, chlorophyll production is low due to iron limitation. Eolian mineral dust represents one of the main Fe sources to the oceans; thus, quantifying its variability over the last glacial cycle is crucial to evaluate its role in strengthening the biological carbon pump. Polar ice cores, which preserve detailed climate records in their stratigraphy, provide a sensitive and continuous archive for reconstructing past eolian Fe fluxes. Here, we show the Northern Hemisphere Fe record retrieved from the NEEM ice core (Greenland), which offers a unique opportunity to reconstruct the past Fe fluxes in a portion of the Arctic over the last 108 kyr. Holocene Fe fluxes (0.042–11.7 ka, 0.5 mg m −2 yr −1 ) at the NEEM site were 4 times lower than the average recorded over the last glacial period (11.7–108 ka, 2.0 mg m −2 yr −1 ), whereas they were greater during the Last Glacial Maximum (LGM; 14.5–26.5 ka, 3.6 mg m −2 yr −1 ) and Marine Isotope Stage 4 (MIS 4; 60–71 ka, 5.8 mg m −2 yr −1 ). Comparing the NEEM Fe record with paleoceanographic records retrieved from the HNLC North Pacific, we found that the coldest periods, characterized by the highest Fe fluxes, were distinguished by low marine primary productivity in the subarctic Pacific Ocean, likely due to the greater sea ice extent and the absence of major nutrients upwelling. This supports the hypothesis that Fe fertilization during colder and dustier periods (i.e., LGM and MIS 4) was more effective in other regions, such as the midlatitude North Pacific, where a closer relationship between marine productivity and the NEEM Fe fluxes was observed. Other/Unknown Material Arctic Greenland ice core Sea ice Subarctic Copernicus Publications: E-Journals Arctic Greenland Pacific Climate of the Past 17 1 491 505 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Iron (Fe) is a key element in the Earth climate system, as it can enhance marine primary productivity in the high-nutrient low-chlorophyll (HNLC) regions where, despite a high concentration of major nutrients, chlorophyll production is low due to iron limitation. Eolian mineral dust represents one of the main Fe sources to the oceans; thus, quantifying its variability over the last glacial cycle is crucial to evaluate its role in strengthening the biological carbon pump. Polar ice cores, which preserve detailed climate records in their stratigraphy, provide a sensitive and continuous archive for reconstructing past eolian Fe fluxes. Here, we show the Northern Hemisphere Fe record retrieved from the NEEM ice core (Greenland), which offers a unique opportunity to reconstruct the past Fe fluxes in a portion of the Arctic over the last 108 kyr. Holocene Fe fluxes (0.042–11.7 ka, 0.5 mg m −2 yr −1 ) at the NEEM site were 4 times lower than the average recorded over the last glacial period (11.7–108 ka, 2.0 mg m −2 yr −1 ), whereas they were greater during the Last Glacial Maximum (LGM; 14.5–26.5 ka, 3.6 mg m −2 yr −1 ) and Marine Isotope Stage 4 (MIS 4; 60–71 ka, 5.8 mg m −2 yr −1 ). Comparing the NEEM Fe record with paleoceanographic records retrieved from the HNLC North Pacific, we found that the coldest periods, characterized by the highest Fe fluxes, were distinguished by low marine primary productivity in the subarctic Pacific Ocean, likely due to the greater sea ice extent and the absence of major nutrients upwelling. This supports the hypothesis that Fe fertilization during colder and dustier periods (i.e., LGM and MIS 4) was more effective in other regions, such as the midlatitude North Pacific, where a closer relationship between marine productivity and the NEEM Fe fluxes was observed. |
format |
Other/Unknown Material |
author |
Burgay, François Spolaor, Andrea Gabrieli, Jacopo Cozzi, Giulio Turetta, Clara Vallelonga, Paul Barbante, Carlo |
spellingShingle |
Burgay, François Spolaor, Andrea Gabrieli, Jacopo Cozzi, Giulio Turetta, Clara Vallelonga, Paul Barbante, Carlo Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean |
author_facet |
Burgay, François Spolaor, Andrea Gabrieli, Jacopo Cozzi, Giulio Turetta, Clara Vallelonga, Paul Barbante, Carlo |
author_sort |
Burgay, François |
title |
Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean |
title_short |
Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean |
title_full |
Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean |
title_fullStr |
Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean |
title_full_unstemmed |
Atmospheric iron supply and marine productivity in the glacial North Pacific Ocean |
title_sort |
atmospheric iron supply and marine productivity in the glacial north pacific ocean |
publishDate |
2021 |
url |
https://doi.org/10.5194/cp-17-491-2021 https://cp.copernicus.org/articles/17/491/2021/ |
geographic |
Arctic Greenland Pacific |
geographic_facet |
Arctic Greenland Pacific |
genre |
Arctic Greenland ice core Sea ice Subarctic |
genre_facet |
Arctic Greenland ice core Sea ice Subarctic |
op_source |
eISSN: 1814-9332 |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/243908 doi:10.5194/cp-17-491-2021 https://cp.copernicus.org/articles/17/491/2021/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/cp-17-491-2021 |
container_title |
Climate of the Past |
container_volume |
17 |
container_issue |
1 |
container_start_page |
491 |
op_container_end_page |
505 |
_version_ |
1766344631918788608 |