Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf?
This study provides dissolved and particulate 230Th and 232Th results as well as particulate 234Th data collected during expeditions to the central Arctic Ocean (GEOTRACES, an international project to identify processes and quantify fluxes that control the distributions of trace elements; sections G...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/402040 2023-08-20T03:59:32+02:00 Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf? Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert L. Lu, Yanbin Puigcorbé, Viena Casacuberta, Núria id_orcid:0 000-0001-7316-1655 Paffrath, Ronja Smethie, William Roy-Barman, Matthieu 2020 application/application/pdf https://hdl.handle.net/20.500.11850/402040 https://doi.org/10.3929/ethz-b-000402040 en eng Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/os-16-221-2020 info:eu-repo/semantics/altIdentifier/wos/000514167200001 info:eu-repo/grantAgreement/SNF/Ambizione/154805 http://hdl.handle.net/20.500.11850/402040 doi:10.3929/ethz-b-000402040 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International Ocean Science, 16 (1) info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2020 ftethz https://doi.org/20.500.11850/40204010.3929/ethz-b-00040204010.5194/os-16-221-2020 2023-07-30T23:51:46Z This study provides dissolved and particulate 230Th and 232Th results as well as particulate 234Th data collected during expeditions to the central Arctic Ocean (GEOTRACES, an international project to identify processes and quantify fluxes that control the distributions of trace elements; sections GN04 and GIPY11). Constructing a time series of dissolved 230Th from 1991 to 2015 enables the identification of processes that control the temporal development of 230Th distributions in the Amundsen Basin. After 2007, 230Th concentrations decreased significantly over the entire water column, particularly between 300 and 1500 m. This decrease is accompanied by a circulation change, evidenced by a concomitant increase in salinity. A potentially increased inflow of water of Atlantic origin with low dissolved 230Th concentrations leads to the observed depletion in dissolved 230Th in the central Arctic. Because atmospherically derived tracers (chlorofluorocarbon (CFC), sulfur hexafluoride (SF6)) do not reveal an increase in ventilation rate, it is suggested that these interior waters have undergone enhanced scavenging of Th during transit from Fram Strait and the Barents Sea to the central Amundsen Basin. The 230Th depletion propagates downward in the water column by settling particles and reversible scavenging. ISSN:1812-0784 ISSN:1812-0792 Article in Journal/Newspaper amundsen basin Arctic Arctic Ocean Barents Sea Fram Strait ETH Zürich Research Collection Amundsen Basin ENVELOPE(74.000,74.000,87.000,87.000) Arctic Arctic Ocean Barents Sea |
institution |
Open Polar |
collection |
ETH Zürich Research Collection |
op_collection_id |
ftethz |
language |
English |
description |
This study provides dissolved and particulate 230Th and 232Th results as well as particulate 234Th data collected during expeditions to the central Arctic Ocean (GEOTRACES, an international project to identify processes and quantify fluxes that control the distributions of trace elements; sections GN04 and GIPY11). Constructing a time series of dissolved 230Th from 1991 to 2015 enables the identification of processes that control the temporal development of 230Th distributions in the Amundsen Basin. After 2007, 230Th concentrations decreased significantly over the entire water column, particularly between 300 and 1500 m. This decrease is accompanied by a circulation change, evidenced by a concomitant increase in salinity. A potentially increased inflow of water of Atlantic origin with low dissolved 230Th concentrations leads to the observed depletion in dissolved 230Th in the central Arctic. Because atmospherically derived tracers (chlorofluorocarbon (CFC), sulfur hexafluoride (SF6)) do not reveal an increase in ventilation rate, it is suggested that these interior waters have undergone enhanced scavenging of Th during transit from Fram Strait and the Barents Sea to the central Amundsen Basin. The 230Th depletion propagates downward in the water column by settling particles and reversible scavenging. ISSN:1812-0784 ISSN:1812-0792 |
format |
Article in Journal/Newspaper |
author |
Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert L. Lu, Yanbin Puigcorbé, Viena Casacuberta, Núria id_orcid:0 000-0001-7316-1655 Paffrath, Ronja Smethie, William Roy-Barman, Matthieu |
spellingShingle |
Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert L. Lu, Yanbin Puigcorbé, Viena Casacuberta, Núria id_orcid:0 000-0001-7316-1655 Paffrath, Ronja Smethie, William Roy-Barman, Matthieu Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf? |
author_facet |
Valk, Ole Rutgers van der Loeff, Michiel M. Geibert, Walter Gdaniec, Sandra Moran, S. Bradley Lepore, Kate Edwards, Robert L. Lu, Yanbin Puigcorbé, Viena Casacuberta, Núria id_orcid:0 000-0001-7316-1655 Paffrath, Ronja Smethie, William Roy-Barman, Matthieu |
author_sort |
Valk, Ole |
title |
Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf? |
title_short |
Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf? |
title_full |
Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf? |
title_fullStr |
Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf? |
title_full_unstemmed |
Decrease in 230Th in the Amundsen Basin since 2007: far-field effect of increased scavenging on the shelf? |
title_sort |
decrease in 230th in the amundsen basin since 2007: far-field effect of increased scavenging on the shelf? |
publisher |
Copernicus |
publishDate |
2020 |
url |
https://hdl.handle.net/20.500.11850/402040 https://doi.org/10.3929/ethz-b-000402040 |
long_lat |
ENVELOPE(74.000,74.000,87.000,87.000) |
geographic |
Amundsen Basin Arctic Arctic Ocean Barents Sea |
geographic_facet |
Amundsen Basin Arctic Arctic Ocean Barents Sea |
genre |
amundsen basin Arctic Arctic Ocean Barents Sea Fram Strait |
genre_facet |
amundsen basin Arctic Arctic Ocean Barents Sea Fram Strait |
op_source |
Ocean Science, 16 (1) |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/os-16-221-2020 info:eu-repo/semantics/altIdentifier/wos/000514167200001 info:eu-repo/grantAgreement/SNF/Ambizione/154805 http://hdl.handle.net/20.500.11850/402040 doi:10.3929/ethz-b-000402040 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International |
op_doi |
https://doi.org/20.500.11850/40204010.3929/ethz-b-00040204010.5194/os-16-221-2020 |
_version_ |
1774713402390740992 |