Mirabilite solubility in equilibrium sea ice brines
The sea ice microstructure is permeated by brine channels and pockets that contain concentrated seawater-derived brine. Cooling the sea ice results in further formation of pure ice within these pockets as thermal equilibrium is attained, resulting in a smaller volume of increasingly concentrated res...
Published in: | Geochimica et Cosmochimica Acta |
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Language: | English |
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2016
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Online Access: | https://research.bangor.ac.uk/portal/en/researchoutputs/mirabilite-solubility-in-equilibrium-sea-ice-brines(f936ea38-72bc-44d0-8721-7ab0b2085baa).html https://doi.org/10.1016/j.gca.2016.03.008 https://research.bangor.ac.uk/ws/files/7662932/7662902.pdf |
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ftuwalesbangcris:oai:research.bangor.ac.uk:publications/f936ea38-72bc-44d0-8721-7ab0b2085baa 2023-05-15T15:02:01+02:00 Mirabilite solubility in equilibrium sea ice brines Butler, Benjamin Papadimitriou, Efstathios Santoro, Anna Kennedy, Hilary 2016-06-01 application/pdf https://research.bangor.ac.uk/portal/en/researchoutputs/mirabilite-solubility-in-equilibrium-sea-ice-brines(f936ea38-72bc-44d0-8721-7ab0b2085baa).html https://doi.org/10.1016/j.gca.2016.03.008 https://research.bangor.ac.uk/ws/files/7662932/7662902.pdf eng eng info:eu-repo/semantics/openAccess Butler , B , Papadimitriou , E , Santoro , A & Kennedy , H 2016 , ' Mirabilite solubility in equilibrium sea ice brines ' , Geochimica et Cosmochimica Acta , vol. 182 , pp. 40-54 . https://doi.org/10.1016/j.gca.2016.03.008 article 2016 ftuwalesbangcris https://doi.org/10.1016/j.gca.2016.03.008 2021-12-26T12:05:29Z The sea ice microstructure is permeated by brine channels and pockets that contain concentrated seawater-derived brine. Cooling the sea ice results in further formation of pure ice within these pockets as thermal equilibrium is attained, resulting in a smaller volume of increasingly concentrated residual brine. The coupled changes in temperature and ionic composition result in supersaturation of the brine with respect to mirabilite (Na2SO4·10H2O) at temperatures below −6.38 °C, which consequently precipitates within the sea ice microstructure. Here, mirabilite solubility in natural and synthetic seawater derived brines, representative of sea ice at thermal equilibrium, has been measured in laboratory experiments between 0.2 and −20.6 °C, and hence we present a detailed examination of mirabilite dynamics within the sea ice system. Below −6.38 °C mirabilite displays particularly large changes in solubility as the temperature decreases, and by −20.6 °C its precipitation results in 12.90% and 91.97% reductions in the total dissolved Na+ and SO42− concentrations respectively, compared to that of conservative seawater concentration. Such large non-conservative changes in brine composition could potentially impact upon the measurement of sea ice brine salinity and pH, whilst the altered osmotic conditions may create additional challenges for the sympagic organisms that inhabit the sea ice system. At temperatures above −6.38 °C, mirabilite again displays large changes in solubility that likely aid in impeding its identification in field samples of sea ice. Our solubility measurements display excellent agreement with that of the FREZCHEM model, which was therefore used to supplement our measurements to colder temperatures. Measured and modelled solubility data were incorporated into a 1D model for the growth of first-year Arctic sea ice. Model results ultimately suggest that mirabilite has a near ubiquitous presence in much of the sea ice on Earth, and illustrate the spatial and temporal evolution of mirabilite within sea ice as it grows throughout an Arctic winter, reaching maximum concentrations of 2.3 g kg−1. Article in Journal/Newspaper Arctic Sea ice Bangor University: Research Portal Arctic Geochimica et Cosmochimica Acta 182 40 54 |
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Open Polar |
collection |
Bangor University: Research Portal |
op_collection_id |
ftuwalesbangcris |
language |
English |
description |
The sea ice microstructure is permeated by brine channels and pockets that contain concentrated seawater-derived brine. Cooling the sea ice results in further formation of pure ice within these pockets as thermal equilibrium is attained, resulting in a smaller volume of increasingly concentrated residual brine. The coupled changes in temperature and ionic composition result in supersaturation of the brine with respect to mirabilite (Na2SO4·10H2O) at temperatures below −6.38 °C, which consequently precipitates within the sea ice microstructure. Here, mirabilite solubility in natural and synthetic seawater derived brines, representative of sea ice at thermal equilibrium, has been measured in laboratory experiments between 0.2 and −20.6 °C, and hence we present a detailed examination of mirabilite dynamics within the sea ice system. Below −6.38 °C mirabilite displays particularly large changes in solubility as the temperature decreases, and by −20.6 °C its precipitation results in 12.90% and 91.97% reductions in the total dissolved Na+ and SO42− concentrations respectively, compared to that of conservative seawater concentration. Such large non-conservative changes in brine composition could potentially impact upon the measurement of sea ice brine salinity and pH, whilst the altered osmotic conditions may create additional challenges for the sympagic organisms that inhabit the sea ice system. At temperatures above −6.38 °C, mirabilite again displays large changes in solubility that likely aid in impeding its identification in field samples of sea ice. Our solubility measurements display excellent agreement with that of the FREZCHEM model, which was therefore used to supplement our measurements to colder temperatures. Measured and modelled solubility data were incorporated into a 1D model for the growth of first-year Arctic sea ice. Model results ultimately suggest that mirabilite has a near ubiquitous presence in much of the sea ice on Earth, and illustrate the spatial and temporal evolution of mirabilite within sea ice as it grows throughout an Arctic winter, reaching maximum concentrations of 2.3 g kg−1. |
format |
Article in Journal/Newspaper |
author |
Butler, Benjamin Papadimitriou, Efstathios Santoro, Anna Kennedy, Hilary |
spellingShingle |
Butler, Benjamin Papadimitriou, Efstathios Santoro, Anna Kennedy, Hilary Mirabilite solubility in equilibrium sea ice brines |
author_facet |
Butler, Benjamin Papadimitriou, Efstathios Santoro, Anna Kennedy, Hilary |
author_sort |
Butler, Benjamin |
title |
Mirabilite solubility in equilibrium sea ice brines |
title_short |
Mirabilite solubility in equilibrium sea ice brines |
title_full |
Mirabilite solubility in equilibrium sea ice brines |
title_fullStr |
Mirabilite solubility in equilibrium sea ice brines |
title_full_unstemmed |
Mirabilite solubility in equilibrium sea ice brines |
title_sort |
mirabilite solubility in equilibrium sea ice brines |
publishDate |
2016 |
url |
https://research.bangor.ac.uk/portal/en/researchoutputs/mirabilite-solubility-in-equilibrium-sea-ice-brines(f936ea38-72bc-44d0-8721-7ab0b2085baa).html https://doi.org/10.1016/j.gca.2016.03.008 https://research.bangor.ac.uk/ws/files/7662932/7662902.pdf |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Sea ice |
genre_facet |
Arctic Sea ice |
op_source |
Butler , B , Papadimitriou , E , Santoro , A & Kennedy , H 2016 , ' Mirabilite solubility in equilibrium sea ice brines ' , Geochimica et Cosmochimica Acta , vol. 182 , pp. 40-54 . https://doi.org/10.1016/j.gca.2016.03.008 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.gca.2016.03.008 |
container_title |
Geochimica et Cosmochimica Acta |
container_volume |
182 |
container_start_page |
40 |
op_container_end_page |
54 |
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1766334015708594176 |