Dissolved organic matter in sea ice
Biogeochemical processes in sea ice and the ice-water interface depend on abiotic processes and biological activity. Abiotic processes in sea ice are controlled by the crystallization process of freezing water and the associated formation of saline brine. Also the heat budget of sea ice and the resu...
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Helsingin yliopisto
2015
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ftunivhelsihelda:oai:helda.helsinki.fi:10138/155620 2023-08-20T04:05:03+02:00 Dissolved organic matter in sea ice from biogeochemical processes during ice formation to bio-optical modelling Müller, Susann Stefels, Jaqueline University of Helsinki, Faculty of Biological and Environmental Sciences, Department of Environmental Sciences Helsingin yliopisto, bio- ja ympäristötieteellinen tiedekunta, ympäristötieteiden laitos Helsingfors universitet, bio- och miljövetenskapliga fakulteten, miljövetenskapliga institutionen Vähätalo, Anssi Granskog, Mats 2015-06-30T10:45:53Z application/pdf http://hdl.handle.net/10138/155620 eng eng Helsingin yliopisto Helsingfors universitet University of Helsinki URN:ISBN:978-952-67851-9-6 Helsinki: Walter and Andrée de Nottbeck Foundation, 2015, WANS Science Report. 0358-6758 http://hdl.handle.net/10138/155620 URN:ISBN:978-952-68391-0-3 Julkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty. This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited. Publikationen är skyddad av upphovsrätten. Den får läsas och skrivas ut för personligt bruk. Användning i kommersiellt syfte är förbjuden. Marine Biogeochemistry Text Doctoral dissertation (article-based) Artikkeliväitöskirja Artikelavhandling doctoralThesis 2015 ftunivhelsihelda 2023-07-28T06:31:13Z Biogeochemical processes in sea ice and the ice-water interface depend on abiotic processes and biological activity. Abiotic processes in sea ice are controlled by the crystallization process of freezing water and the associated formation of saline brine. Also the heat budget of sea ice and the resulting changes in abiotic properties such as porosity and salinity need to be taken into account. The dissolved fraction of sea ice brines contain ions and dissolved organic matter (DOM). Ions are rejected from the ice by diffusion and gravity drainage whereas dissolved organic matter with highly complex and diverse chemical composition can react in many ways with other molecules and surfaces. Hence, the present work compares the behavior of different fractions of DOM to the ones of salts during initial sea ice formation. Controlled tank studies were combined with natural sea ice sampling to exclude the disadvantages of both systems such as the effects of small-scale experiments, artificial additions in tank experiments and the unknown history of natural samples. The studies were conducted with brackish sea ice from the Baltic Sea with its high nutrient and DOM concentrations, but also with oceanic sea ice from the North Sea and the Arctic Ocean. This allows a general conclusion about the behavior of solutes during the formation of sea ice. The present studies indicate that the major seawater ions are significantly fractionated due to differential diffusion and coupled diffuse-convective salt transport through the brine channel network. Ions with a lower diffusivity than Cl¯, in this study SO42¯, Ca+ and Mg2+, remained longer in the brine channel network and got therefore enriched in sea ice relative to Cl¯. K+, on the other hand, diffused faster than Cl¯ and was depleted in sea ice in this study. The behavior of DOM in sea ice was more complex compared to ions because of the complex structure of DOM and the effect of secondary processes on DOM, such as biological production and degradation in sea ice. The ... Doctoral or Postdoctoral Thesis Arctic Arctic Ocean Sea ice Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto Arctic Arctic Ocean |
institution |
Open Polar |
collection |
Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto |
op_collection_id |
ftunivhelsihelda |
language |
English |
topic |
Marine Biogeochemistry |
spellingShingle |
Marine Biogeochemistry Müller, Susann Dissolved organic matter in sea ice |
topic_facet |
Marine Biogeochemistry |
description |
Biogeochemical processes in sea ice and the ice-water interface depend on abiotic processes and biological activity. Abiotic processes in sea ice are controlled by the crystallization process of freezing water and the associated formation of saline brine. Also the heat budget of sea ice and the resulting changes in abiotic properties such as porosity and salinity need to be taken into account. The dissolved fraction of sea ice brines contain ions and dissolved organic matter (DOM). Ions are rejected from the ice by diffusion and gravity drainage whereas dissolved organic matter with highly complex and diverse chemical composition can react in many ways with other molecules and surfaces. Hence, the present work compares the behavior of different fractions of DOM to the ones of salts during initial sea ice formation. Controlled tank studies were combined with natural sea ice sampling to exclude the disadvantages of both systems such as the effects of small-scale experiments, artificial additions in tank experiments and the unknown history of natural samples. The studies were conducted with brackish sea ice from the Baltic Sea with its high nutrient and DOM concentrations, but also with oceanic sea ice from the North Sea and the Arctic Ocean. This allows a general conclusion about the behavior of solutes during the formation of sea ice. The present studies indicate that the major seawater ions are significantly fractionated due to differential diffusion and coupled diffuse-convective salt transport through the brine channel network. Ions with a lower diffusivity than Cl¯, in this study SO42¯, Ca+ and Mg2+, remained longer in the brine channel network and got therefore enriched in sea ice relative to Cl¯. K+, on the other hand, diffused faster than Cl¯ and was depleted in sea ice in this study. The behavior of DOM in sea ice was more complex compared to ions because of the complex structure of DOM and the effect of secondary processes on DOM, such as biological production and degradation in sea ice. The ... |
author2 |
Stefels, Jaqueline University of Helsinki, Faculty of Biological and Environmental Sciences, Department of Environmental Sciences Helsingin yliopisto, bio- ja ympäristötieteellinen tiedekunta, ympäristötieteiden laitos Helsingfors universitet, bio- och miljövetenskapliga fakulteten, miljövetenskapliga institutionen Vähätalo, Anssi Granskog, Mats |
format |
Doctoral or Postdoctoral Thesis |
author |
Müller, Susann |
author_facet |
Müller, Susann |
author_sort |
Müller, Susann |
title |
Dissolved organic matter in sea ice |
title_short |
Dissolved organic matter in sea ice |
title_full |
Dissolved organic matter in sea ice |
title_fullStr |
Dissolved organic matter in sea ice |
title_full_unstemmed |
Dissolved organic matter in sea ice |
title_sort |
dissolved organic matter in sea ice |
publisher |
Helsingin yliopisto |
publishDate |
2015 |
url |
http://hdl.handle.net/10138/155620 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Ocean Sea ice |
genre_facet |
Arctic Arctic Ocean Sea ice |
op_relation |
URN:ISBN:978-952-67851-9-6 Helsinki: Walter and Andrée de Nottbeck Foundation, 2015, WANS Science Report. 0358-6758 http://hdl.handle.net/10138/155620 URN:ISBN:978-952-68391-0-3 |
op_rights |
Julkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty. This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited. Publikationen är skyddad av upphovsrätten. Den får läsas och skrivas ut för personligt bruk. Användning i kommersiellt syfte är förbjuden. |
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1774715475143426048 |