Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice
The carbon dioxide (CO2)-carbonate chemistry of sea-ice melt and co-located, contemporaneous seawater has rarely been studied in sea-ice-covered oceans. Here, we describe the CO2-carbonate chemistry of sea-ice melt (both above sea-ice as "melt ponds" and below sea-ice as "interface wa...
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2014
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Online Access: | https://commons.clarku.edu/faculty_geography/219 https://doi.org/10.5194/bg-11-6769-2014 https://commons.clarku.edu/context/faculty_geography/article/1218/viewcontent/GeogFacWorks_Frey_SeaIce_2014.pdf |
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ftclarkuniv:oai:commons.clarku.edu:faculty_geography-1218 2023-09-05T13:17:24+02:00 Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice Bates, N. R. Garley, R. Frey, K. E. Shake, K. L. Mathis, J. T. 2014-01-01T08:00:00Z application/pdf https://commons.clarku.edu/faculty_geography/219 https://doi.org/10.5194/bg-11-6769-2014 https://commons.clarku.edu/context/faculty_geography/article/1218/viewcontent/GeogFacWorks_Frey_SeaIce_2014.pdf unknown Clark Digital Commons https://commons.clarku.edu/faculty_geography/219 doi:10.5194/bg-11-6769-2014 https://commons.clarku.edu/context/faculty_geography/article/1218/viewcontent/GeogFacWorks_Frey_SeaIce_2014.pdf http://creativecommons.org/licenses/by-nc-nd/4.0/ Geography air-sea interaction carbon dioxide carbonate system gas exchange ice community ice cover mixed layer net primary production sea ice seawater Climate Oceanography text 2014 ftclarkuniv https://doi.org/10.5194/bg-11-6769-2014 2023-08-14T06:16:31Z The carbon dioxide (CO2)-carbonate chemistry of sea-ice melt and co-located, contemporaneous seawater has rarely been studied in sea-ice-covered oceans. Here, we describe the CO2-carbonate chemistry of sea-ice melt (both above sea-ice as "melt ponds" and below sea-ice as "interface waters") and mixed-layer properties in the western Arctic Ocean in the early summer of 2010 and 2011. At 19 stations, the salinity (∼0.5 to <6.5), dissolved inorganic carbon (DIC; ∼20 to <550 μmol kg-1) and total alkalinity (TA; ∼30 to <500 μmol kg-1) of above-ice melt pond water was low compared to the co-located underlying mixed layer. The partial pressure of CO2 (pCO2) in these melt ponds was highly variable (∼<10 to >1500 μatm) with the majority of melt ponds acting as potentially strong sources of CO2 to the atmosphere. The pH of melt pond waters was also highly variable ranging from mildly acidic (6.1 to 7) to slightly more alkaline than underlying seawater (>8.2 to 10.8). All of the observed melt ponds had very low (<0.1) saturation states (Ω) for calcium carbonate (CaCO3) minerals such as aragonite (Ωaragonite). Our data suggest that sea-ice generated alkaline or acidic type melt pond water. This melt water chemistry dictates whether the ponds are sources of CO2 to the atmosphere or CO2 sinks. Below-ice interface water CO2-carbonate chemistry data also indicated substantial generation of alkalinity, presumably owing to dissolution of CaCO3 in sea-ice. The interface waters generally had lower pCO2 and higher pH/Ωaragonite than the co-located mixed layer beneath. Sea-ice melt thus contributed to the suppression of mixed-layer pCO2, thereby enhancing the surface ocean's capacity to uptake CO2 from the atmosphere. Our observations contribute to growing evidence that sea-ice CO2-carbonate chemistry is highly variable and its contribution to the complex factors that influence the balance of CO2 sinks and sources (and thereby ocean acidification) is difficult to predict in an era of rapid warming and sea-ice loss ... Text Arctic Arctic Ocean Ocean acidification Sea ice Clark University: Clark Digital Commons Arctic Arctic Ocean Biogeosciences 11 23 6769 6789 |
institution |
Open Polar |
collection |
Clark University: Clark Digital Commons |
op_collection_id |
ftclarkuniv |
language |
unknown |
topic |
air-sea interaction carbon dioxide carbonate system gas exchange ice community ice cover mixed layer net primary production sea ice seawater Climate Oceanography |
spellingShingle |
air-sea interaction carbon dioxide carbonate system gas exchange ice community ice cover mixed layer net primary production sea ice seawater Climate Oceanography Bates, N. R. Garley, R. Frey, K. E. Shake, K. L. Mathis, J. T. Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice |
topic_facet |
air-sea interaction carbon dioxide carbonate system gas exchange ice community ice cover mixed layer net primary production sea ice seawater Climate Oceanography |
description |
The carbon dioxide (CO2)-carbonate chemistry of sea-ice melt and co-located, contemporaneous seawater has rarely been studied in sea-ice-covered oceans. Here, we describe the CO2-carbonate chemistry of sea-ice melt (both above sea-ice as "melt ponds" and below sea-ice as "interface waters") and mixed-layer properties in the western Arctic Ocean in the early summer of 2010 and 2011. At 19 stations, the salinity (∼0.5 to <6.5), dissolved inorganic carbon (DIC; ∼20 to <550 μmol kg-1) and total alkalinity (TA; ∼30 to <500 μmol kg-1) of above-ice melt pond water was low compared to the co-located underlying mixed layer. The partial pressure of CO2 (pCO2) in these melt ponds was highly variable (∼<10 to >1500 μatm) with the majority of melt ponds acting as potentially strong sources of CO2 to the atmosphere. The pH of melt pond waters was also highly variable ranging from mildly acidic (6.1 to 7) to slightly more alkaline than underlying seawater (>8.2 to 10.8). All of the observed melt ponds had very low (<0.1) saturation states (Ω) for calcium carbonate (CaCO3) minerals such as aragonite (Ωaragonite). Our data suggest that sea-ice generated alkaline or acidic type melt pond water. This melt water chemistry dictates whether the ponds are sources of CO2 to the atmosphere or CO2 sinks. Below-ice interface water CO2-carbonate chemistry data also indicated substantial generation of alkalinity, presumably owing to dissolution of CaCO3 in sea-ice. The interface waters generally had lower pCO2 and higher pH/Ωaragonite than the co-located mixed layer beneath. Sea-ice melt thus contributed to the suppression of mixed-layer pCO2, thereby enhancing the surface ocean's capacity to uptake CO2 from the atmosphere. Our observations contribute to growing evidence that sea-ice CO2-carbonate chemistry is highly variable and its contribution to the complex factors that influence the balance of CO2 sinks and sources (and thereby ocean acidification) is difficult to predict in an era of rapid warming and sea-ice loss ... |
format |
Text |
author |
Bates, N. R. Garley, R. Frey, K. E. Shake, K. L. Mathis, J. T. |
author_facet |
Bates, N. R. Garley, R. Frey, K. E. Shake, K. L. Mathis, J. T. |
author_sort |
Bates, N. R. |
title |
Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice |
title_short |
Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice |
title_full |
Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice |
title_fullStr |
Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice |
title_full_unstemmed |
Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: Meltwater contributions to air-sea CO2 gas exchange, mixed-layer properties and rates of net community production under sea ice |
title_sort |
sea-ice melt co2-carbonate chemistry in the western arctic ocean: meltwater contributions to air-sea co2 gas exchange, mixed-layer properties and rates of net community production under sea ice |
publisher |
Clark Digital Commons |
publishDate |
2014 |
url |
https://commons.clarku.edu/faculty_geography/219 https://doi.org/10.5194/bg-11-6769-2014 https://commons.clarku.edu/context/faculty_geography/article/1218/viewcontent/GeogFacWorks_Frey_SeaIce_2014.pdf |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Ocean Ocean acidification Sea ice |
genre_facet |
Arctic Arctic Ocean Ocean acidification Sea ice |
op_source |
Geography |
op_relation |
https://commons.clarku.edu/faculty_geography/219 doi:10.5194/bg-11-6769-2014 https://commons.clarku.edu/context/faculty_geography/article/1218/viewcontent/GeogFacWorks_Frey_SeaIce_2014.pdf |
op_rights |
http://creativecommons.org/licenses/by-nc-nd/4.0/ |
op_doi |
https://doi.org/10.5194/bg-11-6769-2014 |
container_title |
Biogeosciences |
container_volume |
11 |
container_issue |
23 |
container_start_page |
6769 |
op_container_end_page |
6789 |
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1776198590858788864 |