Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ
Concentrations of the toxic element lead (Pb) are elevated in seawater due to historical emissions. While anthropogenic atmospheric emissions are the dominant source of dissolved Pb (dPb) to the Atlantic Ocean, evidence is emerging of a natural source associated with subglacial discharge into the oc...
Published in: | Geophysical Research Letters |
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Main Authors: | , , , , , |
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Language: | English |
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AGU (American Geophysical Union)
2022
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Online Access: | https://oceanrep.geomar.de/id/eprint/57245/ https://oceanrep.geomar.de/id/eprint/57245/1/Geophysical%20Research%20Letters%20-%202022%20-%20Krisch%20-%20Quantifying%20Ice%E2%80%90Sheet%20Derived%20Lead%20Pb%20Fluxes%20to%20the%20Ocean%20A%20Case%20Study%20at.pdf https://oceanrep.geomar.de/id/eprint/57245/7/2022gl100296-sup-0001-supporting%20information%20si-s01.pdf https://doi.org/10.1029/2022GL100296 |
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ftoceanrep:oai:oceanrep.geomar.de:57245 2024-02-11T10:01:23+01:00 Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ Krisch, Stephan Huhn, Oliver Al-Hashem, Ali Hopwood, Mark J. Lodeiro, Pablo Achterberg, Eric P. 2022-11-16 text https://oceanrep.geomar.de/id/eprint/57245/ https://oceanrep.geomar.de/id/eprint/57245/1/Geophysical%20Research%20Letters%20-%202022%20-%20Krisch%20-%20Quantifying%20Ice%E2%80%90Sheet%20Derived%20Lead%20Pb%20Fluxes%20to%20the%20Ocean%20A%20Case%20Study%20at.pdf https://oceanrep.geomar.de/id/eprint/57245/7/2022gl100296-sup-0001-supporting%20information%20si-s01.pdf https://doi.org/10.1029/2022GL100296 en eng AGU (American Geophysical Union) Wiley https://oceanrep.geomar.de/id/eprint/57245/1/Geophysical%20Research%20Letters%20-%202022%20-%20Krisch%20-%20Quantifying%20Ice%E2%80%90Sheet%20Derived%20Lead%20Pb%20Fluxes%20to%20the%20Ocean%20A%20Case%20Study%20at.pdf https://oceanrep.geomar.de/id/eprint/57245/7/2022gl100296-sup-0001-supporting%20information%20si-s01.pdf Krisch, S. , Huhn, O., Al-Hashem, A., Hopwood, M. J. , Lodeiro, P. and Achterberg, E. P. (2022) Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ. Open Access Geophysical Research Letters, 49 (21). e2022GL100296. DOI 10.1029/2022GL100296 <https://doi.org/10.1029/2022GL100296>. doi:10.1029/2022GL100296 cc_by_nc_4.0 info:eu-repo/semantics/openAccess Article PeerReviewed info:eu-repo/semantics/article 2022 ftoceanrep https://doi.org/10.1029/2022GL100296 2024-01-15T00:26:12Z Concentrations of the toxic element lead (Pb) are elevated in seawater due to historical emissions. While anthropogenic atmospheric emissions are the dominant source of dissolved Pb (dPb) to the Atlantic Ocean, evidence is emerging of a natural source associated with subglacial discharge into the ocean but this has yet to be constrained around Greenland. Here, we show subglacial discharge from the cavity underneath Nioghalvfjerdsbræ floating ice tongue, is a previously unrecognized source of dPb to the NE Greenland Shelf. Contrasting cavity-inflowing and cavity-outflowing waters, we constrain the associated net-dPb flux as 2.2 ± 1.4 Mg·yr−1, of which ∼90% originates from dissolution of glacial bedrock and cavity sediments. We propose that the retreat of the floating ice tongue, the ongoing retreat of many glaciers on Greenland, associated shifts in sediment dynamics, and enhanced meltwater discharges into shelf waters may result in pronounced changes, possibly increases, in net-dPb fluxes to coastal waters. Key Points - Helium and neon show strong evidence for a subglacial source of Pb discharging onto the NE Greenland Shelf - Contrasting inflowing and outflowing waters beneath the floating ice tongue of Nioghalvfjerdsbræ shows a 2-3-fold dPb enrichment - The dissolved Pb flux from Nioghalvfjerdsbræ (2.2 ± 1.4 Mg·yr−1) is comparable to small Arctic rivers, with ∼90% of a sedimentary origin Article in Journal/Newspaper Arctic Greenland Ice Sheet OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Arctic Greenland Geophysical Research Letters 49 21 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Concentrations of the toxic element lead (Pb) are elevated in seawater due to historical emissions. While anthropogenic atmospheric emissions are the dominant source of dissolved Pb (dPb) to the Atlantic Ocean, evidence is emerging of a natural source associated with subglacial discharge into the ocean but this has yet to be constrained around Greenland. Here, we show subglacial discharge from the cavity underneath Nioghalvfjerdsbræ floating ice tongue, is a previously unrecognized source of dPb to the NE Greenland Shelf. Contrasting cavity-inflowing and cavity-outflowing waters, we constrain the associated net-dPb flux as 2.2 ± 1.4 Mg·yr−1, of which ∼90% originates from dissolution of glacial bedrock and cavity sediments. We propose that the retreat of the floating ice tongue, the ongoing retreat of many glaciers on Greenland, associated shifts in sediment dynamics, and enhanced meltwater discharges into shelf waters may result in pronounced changes, possibly increases, in net-dPb fluxes to coastal waters. Key Points - Helium and neon show strong evidence for a subglacial source of Pb discharging onto the NE Greenland Shelf - Contrasting inflowing and outflowing waters beneath the floating ice tongue of Nioghalvfjerdsbræ shows a 2-3-fold dPb enrichment - The dissolved Pb flux from Nioghalvfjerdsbræ (2.2 ± 1.4 Mg·yr−1) is comparable to small Arctic rivers, with ∼90% of a sedimentary origin |
format |
Article in Journal/Newspaper |
author |
Krisch, Stephan Huhn, Oliver Al-Hashem, Ali Hopwood, Mark J. Lodeiro, Pablo Achterberg, Eric P. |
spellingShingle |
Krisch, Stephan Huhn, Oliver Al-Hashem, Ali Hopwood, Mark J. Lodeiro, Pablo Achterberg, Eric P. Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ |
author_facet |
Krisch, Stephan Huhn, Oliver Al-Hashem, Ali Hopwood, Mark J. Lodeiro, Pablo Achterberg, Eric P. |
author_sort |
Krisch, Stephan |
title |
Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ |
title_short |
Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ |
title_full |
Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ |
title_fullStr |
Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ |
title_full_unstemmed |
Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ |
title_sort |
quantifying ice‐sheet derived lead (pb) fluxes to the ocean; a case study at nioghalvfjerdsbræ |
publisher |
AGU (American Geophysical Union) |
publishDate |
2022 |
url |
https://oceanrep.geomar.de/id/eprint/57245/ https://oceanrep.geomar.de/id/eprint/57245/1/Geophysical%20Research%20Letters%20-%202022%20-%20Krisch%20-%20Quantifying%20Ice%E2%80%90Sheet%20Derived%20Lead%20Pb%20Fluxes%20to%20the%20Ocean%20A%20Case%20Study%20at.pdf https://oceanrep.geomar.de/id/eprint/57245/7/2022gl100296-sup-0001-supporting%20information%20si-s01.pdf https://doi.org/10.1029/2022GL100296 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic Greenland Ice Sheet |
genre_facet |
Arctic Greenland Ice Sheet |
op_relation |
https://oceanrep.geomar.de/id/eprint/57245/1/Geophysical%20Research%20Letters%20-%202022%20-%20Krisch%20-%20Quantifying%20Ice%E2%80%90Sheet%20Derived%20Lead%20Pb%20Fluxes%20to%20the%20Ocean%20A%20Case%20Study%20at.pdf https://oceanrep.geomar.de/id/eprint/57245/7/2022gl100296-sup-0001-supporting%20information%20si-s01.pdf Krisch, S. , Huhn, O., Al-Hashem, A., Hopwood, M. J. , Lodeiro, P. and Achterberg, E. P. (2022) Quantifying Ice‐Sheet Derived Lead (Pb) Fluxes to the Ocean; A Case Study at Nioghalvfjerdsbræ. Open Access Geophysical Research Letters, 49 (21). e2022GL100296. DOI 10.1029/2022GL100296 <https://doi.org/10.1029/2022GL100296>. doi:10.1029/2022GL100296 |
op_rights |
cc_by_nc_4.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2022GL100296 |
container_title |
Geophysical Research Letters |
container_volume |
49 |
container_issue |
21 |
_version_ |
1790597200183558144 |