Coastal freshening drives acidification state in Greenland fjords
Greenland's fjords and coastal waters are highly productive and sustain important fisheries. However, retreating glaciers and increasing meltwater are changing fjord circulation and biogeochemistry, which may threaten future productivity. The freshening of Greenland fjords caused by unprecedent...
Published in: | Science of The Total Environment |
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2023
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Online Access: | https://pure.au.dk/portal/da/publications/coastal-freshening-drives-acidification-state-in-greenland-fjords(ac494a71-facc-4847-b990-a3aa6a6a3c28).html https://doi.org/10.1016/j.scitotenv.2022.158962 |
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ftuniaarhuspubl:oai:pure.atira.dk:publications/ac494a71-facc-4847-b990-a3aa6a6a3c28 2023-05-15T15:13:23+02:00 Coastal freshening drives acidification state in Greenland fjords Henson, Henry Holding, Johnna M Meire, Lorenz Rysgaard, Søren Stedmon, Colin Stuart-Lee, Alice Bendtsen, Jørgen Sejr, Mikael 2023-01 https://pure.au.dk/portal/da/publications/coastal-freshening-drives-acidification-state-in-greenland-fjords(ac494a71-facc-4847-b990-a3aa6a6a3c28).html https://doi.org/10.1016/j.scitotenv.2022.158962 eng eng info:eu-repo/semantics/openAccess Henson , H , Holding , J M , Meire , L , Rysgaard , S , Stedmon , C , Stuart-Lee , A , Bendtsen , J & Sejr , M 2023 , ' Coastal freshening drives acidification state in Greenland fjords ' , The Science of the Total Environment , vol. 855 , 158962 . https://doi.org/10.1016/j.scitotenv.2022.158962 Arctic Biological pump CO Carbon dioxide Carbonate saturation state Climate change Freshening Greenland fjord Ocean acidification Seawater chemistry article 2023 ftuniaarhuspubl https://doi.org/10.1016/j.scitotenv.2022.158962 2023-03-15T23:56:14Z Greenland's fjords and coastal waters are highly productive and sustain important fisheries. However, retreating glaciers and increasing meltwater are changing fjord circulation and biogeochemistry, which may threaten future productivity. The freshening of Greenland fjords caused by unprecedented melting of the Greenland Ice Sheet may alter carbonate chemistry in coastal waters, influencing CO 2 uptake and causing biological consequences from acidification. However, few studies to date explore the current acidification state in Greenland coastal waters. Here we present the first-ever large-scale measurements of carbonate system parameters in 16 Greenlandic fjords and seek to identify the drivers of acidification state in these freshening ecosystems. Aragonite saturation state (Ω), a proxy for ocean acidification, was calculated from dissolved inorganic carbon (DIC) and total alkalinity from fjords along the east and west coast of Greenland spanning 68-75°N. Aragonite saturation was primarily >1 in the surface mixed layer. However, undersaturated-or corrosive--conditions (Ω < 1) were observed on both coasts (west: Ω = 0.28-3.11, east: Ω = 0.70-3.07), albeit at different depths. West Greenland fjords were largely corrosive at depth while undersaturation in East Greenland fjords was only observed in surface waters. This reflects a difference in the coastal boundary conditions and mechanisms driving acidification state. We suggest that advection of Sub Polar Mode Water and accumulation of DIC from organic matter decomposition drive corrosive conditions in the West, while freshwater alkalinity dilution drives acidification in the East. The presence of marine terminating glaciers also impacted local acidification states by influencing fjord circulation: upwelling driven by subglacial discharge brought corrosive bottom waters to shallower depths. Meanwhile, discharge from land terminating glaciers strengthened stratification and diluted alkalinity. Regardless of the drivers in each system, increasing freshwater ... Article in Journal/Newspaper Arctic Climate change East Greenland Greenland greenlandic Ice Sheet Ocean acidification Aarhus University: Research Arctic Greenland Science of The Total Environment 855 158962 |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
English |
topic |
Arctic Biological pump CO Carbon dioxide Carbonate saturation state Climate change Freshening Greenland fjord Ocean acidification Seawater chemistry |
spellingShingle |
Arctic Biological pump CO Carbon dioxide Carbonate saturation state Climate change Freshening Greenland fjord Ocean acidification Seawater chemistry Henson, Henry Holding, Johnna M Meire, Lorenz Rysgaard, Søren Stedmon, Colin Stuart-Lee, Alice Bendtsen, Jørgen Sejr, Mikael Coastal freshening drives acidification state in Greenland fjords |
topic_facet |
Arctic Biological pump CO Carbon dioxide Carbonate saturation state Climate change Freshening Greenland fjord Ocean acidification Seawater chemistry |
description |
Greenland's fjords and coastal waters are highly productive and sustain important fisheries. However, retreating glaciers and increasing meltwater are changing fjord circulation and biogeochemistry, which may threaten future productivity. The freshening of Greenland fjords caused by unprecedented melting of the Greenland Ice Sheet may alter carbonate chemistry in coastal waters, influencing CO 2 uptake and causing biological consequences from acidification. However, few studies to date explore the current acidification state in Greenland coastal waters. Here we present the first-ever large-scale measurements of carbonate system parameters in 16 Greenlandic fjords and seek to identify the drivers of acidification state in these freshening ecosystems. Aragonite saturation state (Ω), a proxy for ocean acidification, was calculated from dissolved inorganic carbon (DIC) and total alkalinity from fjords along the east and west coast of Greenland spanning 68-75°N. Aragonite saturation was primarily >1 in the surface mixed layer. However, undersaturated-or corrosive--conditions (Ω < 1) were observed on both coasts (west: Ω = 0.28-3.11, east: Ω = 0.70-3.07), albeit at different depths. West Greenland fjords were largely corrosive at depth while undersaturation in East Greenland fjords was only observed in surface waters. This reflects a difference in the coastal boundary conditions and mechanisms driving acidification state. We suggest that advection of Sub Polar Mode Water and accumulation of DIC from organic matter decomposition drive corrosive conditions in the West, while freshwater alkalinity dilution drives acidification in the East. The presence of marine terminating glaciers also impacted local acidification states by influencing fjord circulation: upwelling driven by subglacial discharge brought corrosive bottom waters to shallower depths. Meanwhile, discharge from land terminating glaciers strengthened stratification and diluted alkalinity. Regardless of the drivers in each system, increasing freshwater ... |
format |
Article in Journal/Newspaper |
author |
Henson, Henry Holding, Johnna M Meire, Lorenz Rysgaard, Søren Stedmon, Colin Stuart-Lee, Alice Bendtsen, Jørgen Sejr, Mikael |
author_facet |
Henson, Henry Holding, Johnna M Meire, Lorenz Rysgaard, Søren Stedmon, Colin Stuart-Lee, Alice Bendtsen, Jørgen Sejr, Mikael |
author_sort |
Henson, Henry |
title |
Coastal freshening drives acidification state in Greenland fjords |
title_short |
Coastal freshening drives acidification state in Greenland fjords |
title_full |
Coastal freshening drives acidification state in Greenland fjords |
title_fullStr |
Coastal freshening drives acidification state in Greenland fjords |
title_full_unstemmed |
Coastal freshening drives acidification state in Greenland fjords |
title_sort |
coastal freshening drives acidification state in greenland fjords |
publishDate |
2023 |
url |
https://pure.au.dk/portal/da/publications/coastal-freshening-drives-acidification-state-in-greenland-fjords(ac494a71-facc-4847-b990-a3aa6a6a3c28).html https://doi.org/10.1016/j.scitotenv.2022.158962 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic Climate change East Greenland Greenland greenlandic Ice Sheet Ocean acidification |
genre_facet |
Arctic Climate change East Greenland Greenland greenlandic Ice Sheet Ocean acidification |
op_source |
Henson , H , Holding , J M , Meire , L , Rysgaard , S , Stedmon , C , Stuart-Lee , A , Bendtsen , J & Sejr , M 2023 , ' Coastal freshening drives acidification state in Greenland fjords ' , The Science of the Total Environment , vol. 855 , 158962 . https://doi.org/10.1016/j.scitotenv.2022.158962 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.scitotenv.2022.158962 |
container_title |
Science of The Total Environment |
container_volume |
855 |
container_start_page |
158962 |
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1766343938200829952 |