The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean
This study explores for the first time the possibilities that the U-233/U-236 atom ratio offers to distinguish waters of Atlantic or Pacific origin in the Arctic Ocean. Atlantic waters entering the Arctic Ocean often carry an isotopic signature dominantly originating from European reprocessing facil...
Published in: | Journal of Geophysical Research: Oceans |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Linköpings universitet, Avdelningen för diagnostik och specialistmedicin
2022
|
Subjects: | |
Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-184397 https://doi.org/10.1029/2021JC017790 |
id |
ftlinkoepinguniv:oai:DiVA.org:liu-184397 |
---|---|
record_format |
openpolar |
spelling |
ftlinkoepinguniv:oai:DiVA.org:liu-184397 2023-05-15T14:37:35+02:00 The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean Chamizo, E. Christl, M. López Lora, Mercedes Casacuberta, N. Wefing, A. -M. Kenna, T. C. 2022 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-184397 https://doi.org/10.1029/2021JC017790 eng eng Linköpings universitet, Avdelningen för diagnostik och specialistmedicin Linköpings universitet, Medicinska fakulteten Univ Seville, Spain Swiss Fed Inst Technol, Switzerland Swiss Fed Inst Technol, Switzerland; Swiss Fed Inst Technol, Switzerland Columbia Univ, NY 10964 USA Wiley-Blackwell Publishing, Inc. Journal of Geophysical Research - Oceans, 2169-9275, 2022, 127:3, http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-184397 doi:10.1029/2021JC017790 ISI:000776507900003 info:eu-repo/semantics/openAccess Arctic Ocean GN01 GEOTRACES section chemical tracers water masses Oceanography Hydrology and Water Resources Oceanografi hydrologi och vattenresurser Article in journal info:eu-repo/semantics/article text 2022 ftlinkoepinguniv https://doi.org/10.1029/2021JC017790 2022-05-18T22:27:32Z This study explores for the first time the possibilities that the U-233/U-236 atom ratio offers to distinguish waters of Atlantic or Pacific origin in the Arctic Ocean. Atlantic waters entering the Arctic Ocean often carry an isotopic signature dominantly originating from European reprocessing facilities with some smaller contribution from global fallout nuclides, whereas northern Pacific waters are labeled with nuclides released during the atmospheric nuclear testing period only. In the Arctic Ocean, U-233 originates from global fallout while U-236 carries both, a global fallout and a prominent nuclear reprocessing signal. Thus, the U-233/U-236 ratio provides a tool to identify water masses with distinct U sources. In this work, U-233 and U-236 were analyzed in samples from the GN01 GEOTRACES expedition to the western Arctic Ocean in 2015. The study of depth profiles and surface seawater samples shows that: (a) Pacific and Atlantic waters show enhanced signals of both radionuclides, which can be unraveled based on their U-233/U-236 signature; and (b) Deep and Bottom Waters show extremely low U-233 and U-236 concentrations close to or below analytical detection limits with isotopic ratios distinct from known anthropogenic U sources. The comparably high U-233/U-236 ratios are interpreted as a relative increase of naturally occurring U-233 and U-236 and thus for gradually reaching natural U-233/U-236 levels in the deep Arctic Ocean. Our results set the basis for future studies using the U-233/U-236 ratio to distinguish anthropogenic and pre-anthropogenic U in the Arctic Ocean and beyond. Funding Agencies|ETH Zurich Research GrantETH Zurich [ETH-06 16-1]; Swiss National Science FoundationSwiss National Science Foundation (SNSF)European Commission [PRIMA SNF PR00P2_193091]; Spanish Government (Ministerio de Ciencia, Innovacion y Universidades)Spanish Government [PGC2018-094546-B-I00] Article in Journal/Newspaper Arctic Arctic Ocean LIU - Linköping University: Publications (DiVA) Arctic Arctic Ocean Pacific Journal of Geophysical Research: Oceans 127 3 |
institution |
Open Polar |
collection |
LIU - Linköping University: Publications (DiVA) |
op_collection_id |
ftlinkoepinguniv |
language |
English |
topic |
Arctic Ocean GN01 GEOTRACES section chemical tracers water masses Oceanography Hydrology and Water Resources Oceanografi hydrologi och vattenresurser |
spellingShingle |
Arctic Ocean GN01 GEOTRACES section chemical tracers water masses Oceanography Hydrology and Water Resources Oceanografi hydrologi och vattenresurser Chamizo, E. Christl, M. López Lora, Mercedes Casacuberta, N. Wefing, A. -M. Kenna, T. C. The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean |
topic_facet |
Arctic Ocean GN01 GEOTRACES section chemical tracers water masses Oceanography Hydrology and Water Resources Oceanografi hydrologi och vattenresurser |
description |
This study explores for the first time the possibilities that the U-233/U-236 atom ratio offers to distinguish waters of Atlantic or Pacific origin in the Arctic Ocean. Atlantic waters entering the Arctic Ocean often carry an isotopic signature dominantly originating from European reprocessing facilities with some smaller contribution from global fallout nuclides, whereas northern Pacific waters are labeled with nuclides released during the atmospheric nuclear testing period only. In the Arctic Ocean, U-233 originates from global fallout while U-236 carries both, a global fallout and a prominent nuclear reprocessing signal. Thus, the U-233/U-236 ratio provides a tool to identify water masses with distinct U sources. In this work, U-233 and U-236 were analyzed in samples from the GN01 GEOTRACES expedition to the western Arctic Ocean in 2015. The study of depth profiles and surface seawater samples shows that: (a) Pacific and Atlantic waters show enhanced signals of both radionuclides, which can be unraveled based on their U-233/U-236 signature; and (b) Deep and Bottom Waters show extremely low U-233 and U-236 concentrations close to or below analytical detection limits with isotopic ratios distinct from known anthropogenic U sources. The comparably high U-233/U-236 ratios are interpreted as a relative increase of naturally occurring U-233 and U-236 and thus for gradually reaching natural U-233/U-236 levels in the deep Arctic Ocean. Our results set the basis for future studies using the U-233/U-236 ratio to distinguish anthropogenic and pre-anthropogenic U in the Arctic Ocean and beyond. Funding Agencies|ETH Zurich Research GrantETH Zurich [ETH-06 16-1]; Swiss National Science FoundationSwiss National Science Foundation (SNSF)European Commission [PRIMA SNF PR00P2_193091]; Spanish Government (Ministerio de Ciencia, Innovacion y Universidades)Spanish Government [PGC2018-094546-B-I00] |
format |
Article in Journal/Newspaper |
author |
Chamizo, E. Christl, M. López Lora, Mercedes Casacuberta, N. Wefing, A. -M. Kenna, T. C. |
author_facet |
Chamizo, E. Christl, M. López Lora, Mercedes Casacuberta, N. Wefing, A. -M. Kenna, T. C. |
author_sort |
Chamizo, E. |
title |
The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean |
title_short |
The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean |
title_full |
The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean |
title_fullStr |
The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean |
title_full_unstemmed |
The Potential of U-233/U-236 as a Water Mass Tracer in the Arctic Ocean |
title_sort |
potential of u-233/u-236 as a water mass tracer in the arctic ocean |
publisher |
Linköpings universitet, Avdelningen för diagnostik och specialistmedicin |
publishDate |
2022 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-184397 https://doi.org/10.1029/2021JC017790 |
geographic |
Arctic Arctic Ocean Pacific |
geographic_facet |
Arctic Arctic Ocean Pacific |
genre |
Arctic Arctic Ocean |
genre_facet |
Arctic Arctic Ocean |
op_relation |
Journal of Geophysical Research - Oceans, 2169-9275, 2022, 127:3, http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-184397 doi:10.1029/2021JC017790 ISI:000776507900003 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2021JC017790 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
127 |
container_issue |
3 |
_version_ |
1766309822193467392 |