Air-ice carbon pathways inferred from a sea ice tank experiment
Given rapid sea ice changes in the Arctic Ocean in the context of climate warming, better constraints on the role of sea ice in CO 2 cycling are needed to assess the capacity of polar oceans to buffer the rise of atmospheric CO 2 concentration. Air-ice CO 2 fluxes were measured continuously using au...
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ftunivtasecite:oai:ecite.utas.edu.au:114433 2023-05-15T15:19:00+02:00 Air-ice carbon pathways inferred from a sea ice tank experiment Kotovich, M Moreau, S Zhou, J Vancoppenolle, M Dieckmann, GS Evers, K-U Van der Linden, F Thomas, DN Tison, J-L Delille, B 2016 application/pdf https://doi.org/10.12952/journal.elementa.000112 http://ecite.utas.edu.au/114433 en eng BioOne http://ecite.utas.edu.au/114433/1/Kotovitch_et_al_2016_CO2_fluxes_Interice.pdf http://dx.doi.org/10.12952/journal.elementa.000112 Kotovich, M and Moreau, S and Zhou, J and Vancoppenolle, M and Dieckmann, GS and Evers, K-U and Van der Linden, F and Thomas, DN and Tison, J-L and Delille, B, Air-ice carbon pathways inferred from a sea ice tank experiment, Elementa, 4 Article 112. ISSN 2325-1026 (2016) [Refereed Article] http://ecite.utas.edu.au/114433 Earth Sciences Oceanography Biological Oceanography Refereed Article PeerReviewed 2016 ftunivtasecite https://doi.org/10.12952/journal.elementa.000112 2019-12-13T22:14:17Z Given rapid sea ice changes in the Arctic Ocean in the context of climate warming, better constraints on the role of sea ice in CO 2 cycling are needed to assess the capacity of polar oceans to buffer the rise of atmospheric CO 2 concentration. Air-ice CO 2 fluxes were measured continuously using automated chambers from the initial freezing of a sea ice cover until its decay during the INTERICE V experiment at the Hamburg Ship Model Basin. Cooling seawater prior to sea ice formation acted as a sink for atmospheric CO 2 , but as soon as the first ice crystals started to form, sea ice turned to a source of CO 2 , which lasted throughout the whole ice growth phase. Once ice decay was initiated by warming the atmosphere, the sea ice shifted back again to a sink of CO 2 . Direct measurements of outward ice-atmosphere CO 2 fluxes were consistent with the depletion of dissolved inorganic carbon in the upper half of sea ice. Combining measured air-ice CO 2 fluxes with the partial pressure of CO 2 in sea ice, we determined strongly different gas transfer coefficients of CO 2 at the air-ice interface between the growth and the decay phases (from 2.5 to 0.4 mol m −2 d −1 atm −1 ). A 1D sea ice carbon cycle model including gas physics and carbon biogeochemistry was used in various configurations in order to interpret the observations. All model simulations correctly predicted the sign of the air-ice flux. By contrast, the amplitude of the flux was much more variable between the different simulations. In none of the simulations was the dissolved gas pathway strong enough to explain the large fluxes during ice growth. This pathway weakness is due to an intrinsic limitation of ice-air fluxes of dissolved CO 2 by the slow transport of dissolved inorganic carbon in the ice. The best means we found to explain the high air-ice carbon fluxes during ice growth is an intense yet uncertain gas bubble efflux, requiring sufficient bubble nucleation and upwards rise. We therefore call for further investigation of gas bubble nucleation and transport in sea ice. Article in Journal/Newspaper Arctic Arctic Ocean Sea ice eCite UTAS (University of Tasmania) Arctic Arctic Ocean Elementa: Science of the Anthropocene 4 |
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Open Polar |
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eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Oceanography Biological Oceanography |
spellingShingle |
Earth Sciences Oceanography Biological Oceanography Kotovich, M Moreau, S Zhou, J Vancoppenolle, M Dieckmann, GS Evers, K-U Van der Linden, F Thomas, DN Tison, J-L Delille, B Air-ice carbon pathways inferred from a sea ice tank experiment |
topic_facet |
Earth Sciences Oceanography Biological Oceanography |
description |
Given rapid sea ice changes in the Arctic Ocean in the context of climate warming, better constraints on the role of sea ice in CO 2 cycling are needed to assess the capacity of polar oceans to buffer the rise of atmospheric CO 2 concentration. Air-ice CO 2 fluxes were measured continuously using automated chambers from the initial freezing of a sea ice cover until its decay during the INTERICE V experiment at the Hamburg Ship Model Basin. Cooling seawater prior to sea ice formation acted as a sink for atmospheric CO 2 , but as soon as the first ice crystals started to form, sea ice turned to a source of CO 2 , which lasted throughout the whole ice growth phase. Once ice decay was initiated by warming the atmosphere, the sea ice shifted back again to a sink of CO 2 . Direct measurements of outward ice-atmosphere CO 2 fluxes were consistent with the depletion of dissolved inorganic carbon in the upper half of sea ice. Combining measured air-ice CO 2 fluxes with the partial pressure of CO 2 in sea ice, we determined strongly different gas transfer coefficients of CO 2 at the air-ice interface between the growth and the decay phases (from 2.5 to 0.4 mol m −2 d −1 atm −1 ). A 1D sea ice carbon cycle model including gas physics and carbon biogeochemistry was used in various configurations in order to interpret the observations. All model simulations correctly predicted the sign of the air-ice flux. By contrast, the amplitude of the flux was much more variable between the different simulations. In none of the simulations was the dissolved gas pathway strong enough to explain the large fluxes during ice growth. This pathway weakness is due to an intrinsic limitation of ice-air fluxes of dissolved CO 2 by the slow transport of dissolved inorganic carbon in the ice. The best means we found to explain the high air-ice carbon fluxes during ice growth is an intense yet uncertain gas bubble efflux, requiring sufficient bubble nucleation and upwards rise. We therefore call for further investigation of gas bubble nucleation and transport in sea ice. |
format |
Article in Journal/Newspaper |
author |
Kotovich, M Moreau, S Zhou, J Vancoppenolle, M Dieckmann, GS Evers, K-U Van der Linden, F Thomas, DN Tison, J-L Delille, B |
author_facet |
Kotovich, M Moreau, S Zhou, J Vancoppenolle, M Dieckmann, GS Evers, K-U Van der Linden, F Thomas, DN Tison, J-L Delille, B |
author_sort |
Kotovich, M |
title |
Air-ice carbon pathways inferred from a sea ice tank experiment |
title_short |
Air-ice carbon pathways inferred from a sea ice tank experiment |
title_full |
Air-ice carbon pathways inferred from a sea ice tank experiment |
title_fullStr |
Air-ice carbon pathways inferred from a sea ice tank experiment |
title_full_unstemmed |
Air-ice carbon pathways inferred from a sea ice tank experiment |
title_sort |
air-ice carbon pathways inferred from a sea ice tank experiment |
publisher |
BioOne |
publishDate |
2016 |
url |
https://doi.org/10.12952/journal.elementa.000112 http://ecite.utas.edu.au/114433 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Ocean Sea ice |
genre_facet |
Arctic Arctic Ocean Sea ice |
op_relation |
http://ecite.utas.edu.au/114433/1/Kotovitch_et_al_2016_CO2_fluxes_Interice.pdf http://dx.doi.org/10.12952/journal.elementa.000112 Kotovich, M and Moreau, S and Zhou, J and Vancoppenolle, M and Dieckmann, GS and Evers, K-U and Van der Linden, F and Thomas, DN and Tison, J-L and Delille, B, Air-ice carbon pathways inferred from a sea ice tank experiment, Elementa, 4 Article 112. ISSN 2325-1026 (2016) [Refereed Article] http://ecite.utas.edu.au/114433 |
op_doi |
https://doi.org/10.12952/journal.elementa.000112 |
container_title |
Elementa: Science of the Anthropocene |
container_volume |
4 |
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1766349195678056448 |