Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump
The Arctic Ocean is generally undersaturated in CO2 and acts as a net sink of atmospheric CO2. This oceanic uptake is strongly modulated by sea ice, which can prevent air–sea gas exchange and has major impacts on stratification and primary production. Moreover, carbon is stored in sea ice with a rat...
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Online Access: | https://hdl.handle.net/11250/3131346 https://doi.org/10.5194/tc-17-2665-2023 |
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ftnorce:oai:norceresearch.brage.unit.no:11250/3131346 2024-06-23T07:49:38+00:00 Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump Richaud, Benjamin Fennel, Katja Oliver, Eric C. J. Degrandpre, Michael D. Bourgeois, Timothée Hu, Xianmin Lu, Youyu 2023 application/pdf https://hdl.handle.net/11250/3131346 https://doi.org/10.5194/tc-17-2665-2023 eng eng Norges forskningsråd: 275268 EC/H2020/820989 The Cryosphere. 2023, 17 (7), 2665-2680. urn:issn:1994-0416 https://hdl.handle.net/11250/3131346 https://doi.org/10.5194/tc-17-2665-2023 cristin:2176924 Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no © 2023 by the authors The Cryosphere 17 7 2665-2680 Peer reviewed Journal article 2023 ftnorce https://doi.org/10.5194/tc-17-2665-2023 2024-05-27T03:05:09Z The Arctic Ocean is generally undersaturated in CO2 and acts as a net sink of atmospheric CO2. This oceanic uptake is strongly modulated by sea ice, which can prevent air–sea gas exchange and has major impacts on stratification and primary production. Moreover, carbon is stored in sea ice with a ratio of alkalinity to dissolved inorganic carbon that is larger than in seawater. It has been suggested that this storage amplifies the seasonal cycle of seawater pCO2 and leads to an increase in oceanic carbon uptake in seasonally ice-covered regions compared to those that are ice-free. Given the rapidly changing ice scape in the Arctic Ocean, a better understanding of the link between the seasonal cycle of sea ice and oceanic uptake of CO2 is needed. Here, we investigate how the storage of carbon in sea ice affects the air–sea CO2 flux and quantify its dependence on the ratio of alkalinity to inorganic carbon in ice. To this end, we present two independent approaches: a theoretical framework that provides an analytical expression of the amplification of carbon uptake in seasonally ice-covered oceans and a simple parameterization of carbon storage in sea ice implemented in a 1D physical–biogeochemical ocean model. Sensitivity simulations show a linear relation between ice melt and the amplification of seasonal carbon uptake. A 30 % increase in carbon uptake in the Arctic Ocean is estimated compared to ice melt without amplification. Applying this relationship to different future scenarios from an earth system model that does not account for the effect of carbon storage in sea ice suggests that Arctic Ocean carbon uptake is underestimated by 5 % to 15 % in these simulations. publishedVersion Article in Journal/Newspaper Arctic Arctic Ocean Sea ice The Cryosphere NORCE vitenarkiv (Norwegian Research Centre) Arctic Arctic Ocean The Cryosphere 17 7 2665 2680 |
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Open Polar |
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NORCE vitenarkiv (Norwegian Research Centre) |
op_collection_id |
ftnorce |
language |
English |
description |
The Arctic Ocean is generally undersaturated in CO2 and acts as a net sink of atmospheric CO2. This oceanic uptake is strongly modulated by sea ice, which can prevent air–sea gas exchange and has major impacts on stratification and primary production. Moreover, carbon is stored in sea ice with a ratio of alkalinity to dissolved inorganic carbon that is larger than in seawater. It has been suggested that this storage amplifies the seasonal cycle of seawater pCO2 and leads to an increase in oceanic carbon uptake in seasonally ice-covered regions compared to those that are ice-free. Given the rapidly changing ice scape in the Arctic Ocean, a better understanding of the link between the seasonal cycle of sea ice and oceanic uptake of CO2 is needed. Here, we investigate how the storage of carbon in sea ice affects the air–sea CO2 flux and quantify its dependence on the ratio of alkalinity to inorganic carbon in ice. To this end, we present two independent approaches: a theoretical framework that provides an analytical expression of the amplification of carbon uptake in seasonally ice-covered oceans and a simple parameterization of carbon storage in sea ice implemented in a 1D physical–biogeochemical ocean model. Sensitivity simulations show a linear relation between ice melt and the amplification of seasonal carbon uptake. A 30 % increase in carbon uptake in the Arctic Ocean is estimated compared to ice melt without amplification. Applying this relationship to different future scenarios from an earth system model that does not account for the effect of carbon storage in sea ice suggests that Arctic Ocean carbon uptake is underestimated by 5 % to 15 % in these simulations. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Richaud, Benjamin Fennel, Katja Oliver, Eric C. J. Degrandpre, Michael D. Bourgeois, Timothée Hu, Xianmin Lu, Youyu |
spellingShingle |
Richaud, Benjamin Fennel, Katja Oliver, Eric C. J. Degrandpre, Michael D. Bourgeois, Timothée Hu, Xianmin Lu, Youyu Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump |
author_facet |
Richaud, Benjamin Fennel, Katja Oliver, Eric C. J. Degrandpre, Michael D. Bourgeois, Timothée Hu, Xianmin Lu, Youyu |
author_sort |
Richaud, Benjamin |
title |
Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump |
title_short |
Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump |
title_full |
Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump |
title_fullStr |
Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump |
title_full_unstemmed |
Underestimation of oceanic carbon uptake in the Arctic Ocean: ice melt as predictor of the sea ice carbon pump |
title_sort |
underestimation of oceanic carbon uptake in the arctic ocean: ice melt as predictor of the sea ice carbon pump |
publishDate |
2023 |
url |
https://hdl.handle.net/11250/3131346 https://doi.org/10.5194/tc-17-2665-2023 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Ocean Sea ice The Cryosphere |
genre_facet |
Arctic Arctic Ocean Sea ice The Cryosphere |
op_source |
The Cryosphere 17 7 2665-2680 |
op_relation |
Norges forskningsråd: 275268 EC/H2020/820989 The Cryosphere. 2023, 17 (7), 2665-2680. urn:issn:1994-0416 https://hdl.handle.net/11250/3131346 https://doi.org/10.5194/tc-17-2665-2023 cristin:2176924 |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no © 2023 by the authors |
op_doi |
https://doi.org/10.5194/tc-17-2665-2023 |
container_title |
The Cryosphere |
container_volume |
17 |
container_issue |
7 |
container_start_page |
2665 |
op_container_end_page |
2680 |
_version_ |
1802640158947803136 |