Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period
Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 120 (2015): 3542-3566, doi:10.1002/2014JC010620. We pr...
Published in: | Journal of Geophysical Research: Oceans |
---|---|
Main Authors: | , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
John Wiley & Sons
2015
|
Subjects: | |
Online Access: | https://hdl.handle.net/1912/7427 |
id |
ftwhoas:oai:darchive.mblwhoilibrary.org:1912/7427 |
---|---|
record_format |
openpolar |
spelling |
ftwhoas:oai:darchive.mblwhoilibrary.org:1912/7427 2023-05-15T14:28:59+02:00 Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period Brown, Kristina A. Miller, Lisa A. Mundy, Christopher J. Papakyriakou, Tim Francois, Roger Gosselin, Michel Carnat, Gauthier Swystun, Kyle Tortell, Philippe D. 2015-05-19 application/pdf https://hdl.handle.net/1912/7427 en_US eng John Wiley & Sons https://doi.org/10.1002/2014JC010620 Journal of Geophysical Research: Oceans 120 (2015): 3542-3566 https://hdl.handle.net/1912/7427 doi:10.1002/2014JC010620 Journal of Geophysical Research: Oceans 120 (2015): 3542-3566 doi:10.1002/2014JC010620 Sea ice Carbon cycling CO2 Brines Stable isotopes Arctic Ocean Article 2015 ftwhoas https://doi.org/10.1002/2014JC010620 2022-05-28T22:59:23Z Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 120 (2015): 3542-3566, doi:10.1002/2014JC010620. We present the results of a 6 week time series of carbonate system and stable isotope measurements investigating the effects of sea ice on air-sea CO2 exchange during the early melt period in the Canadian Arctic Archipelago. Our observations revealed significant changes in sea ice and sackhole brine carbonate system parameters that were associated with increasing temperatures and the buildup of chlorophyll a in bottom ice. The warming sea-ice column could be separated into distinct geochemical zones where biotic and abiotic processes exerted different influences on inorganic carbon and pCO2 distributions. In the bottom ice, biological carbon uptake maintained undersaturated pCO2 conditions throughout the time series, while pCO2 was supersaturated in the upper ice. Low CO2 permeability of the sea ice matrix and snow cover effectively impeded CO2 efflux to the atmosphere, despite a strong pCO2 gradient. Throughout the middle of the ice column, brine pCO2 decreased significantly with time and was tightly controlled by solubility, as sea ice temperature and in situ melt dilution increased. Once the influence of melt dilution was accounted for, both CaCO3 dissolution and seawater mixing were found to contribute alkalinity and dissolved inorganic carbon to brines, with the CaCO3 contribution driving brine pCO2 to values lower than predicted from melt-water dilution alone. This field study reveals a dynamic carbon system within the rapidly warming sea ice, prior to snow melt. We suggest that the early spring period drives the ice column toward pCO2 undersaturation, contributing to a weak atmospheric CO2 sink as the melt period advances. We acknowledge support from the Polar Continental Shelf Program (PCSP) of Natural ... Article in Journal/Newspaper Arctic Archipelago Arctic Arctic Ocean Canadian Arctic Archipelago Sea ice Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Arctic Arctic Ocean Canadian Arctic Archipelago Journal of Geophysical Research: Oceans 120 5 3542 3566 |
institution |
Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
op_collection_id |
ftwhoas |
language |
English |
topic |
Sea ice Carbon cycling CO2 Brines Stable isotopes Arctic Ocean |
spellingShingle |
Sea ice Carbon cycling CO2 Brines Stable isotopes Arctic Ocean Brown, Kristina A. Miller, Lisa A. Mundy, Christopher J. Papakyriakou, Tim Francois, Roger Gosselin, Michel Carnat, Gauthier Swystun, Kyle Tortell, Philippe D. Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period |
topic_facet |
Sea ice Carbon cycling CO2 Brines Stable isotopes Arctic Ocean |
description |
Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 120 (2015): 3542-3566, doi:10.1002/2014JC010620. We present the results of a 6 week time series of carbonate system and stable isotope measurements investigating the effects of sea ice on air-sea CO2 exchange during the early melt period in the Canadian Arctic Archipelago. Our observations revealed significant changes in sea ice and sackhole brine carbonate system parameters that were associated with increasing temperatures and the buildup of chlorophyll a in bottom ice. The warming sea-ice column could be separated into distinct geochemical zones where biotic and abiotic processes exerted different influences on inorganic carbon and pCO2 distributions. In the bottom ice, biological carbon uptake maintained undersaturated pCO2 conditions throughout the time series, while pCO2 was supersaturated in the upper ice. Low CO2 permeability of the sea ice matrix and snow cover effectively impeded CO2 efflux to the atmosphere, despite a strong pCO2 gradient. Throughout the middle of the ice column, brine pCO2 decreased significantly with time and was tightly controlled by solubility, as sea ice temperature and in situ melt dilution increased. Once the influence of melt dilution was accounted for, both CaCO3 dissolution and seawater mixing were found to contribute alkalinity and dissolved inorganic carbon to brines, with the CaCO3 contribution driving brine pCO2 to values lower than predicted from melt-water dilution alone. This field study reveals a dynamic carbon system within the rapidly warming sea ice, prior to snow melt. We suggest that the early spring period drives the ice column toward pCO2 undersaturation, contributing to a weak atmospheric CO2 sink as the melt period advances. We acknowledge support from the Polar Continental Shelf Program (PCSP) of Natural ... |
format |
Article in Journal/Newspaper |
author |
Brown, Kristina A. Miller, Lisa A. Mundy, Christopher J. Papakyriakou, Tim Francois, Roger Gosselin, Michel Carnat, Gauthier Swystun, Kyle Tortell, Philippe D. |
author_facet |
Brown, Kristina A. Miller, Lisa A. Mundy, Christopher J. Papakyriakou, Tim Francois, Roger Gosselin, Michel Carnat, Gauthier Swystun, Kyle Tortell, Philippe D. |
author_sort |
Brown, Kristina A. |
title |
Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period |
title_short |
Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period |
title_full |
Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period |
title_fullStr |
Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period |
title_full_unstemmed |
Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period |
title_sort |
inorganic carbon system dynamics in landfast arctic sea ice during the early-melt period |
publisher |
John Wiley & Sons |
publishDate |
2015 |
url |
https://hdl.handle.net/1912/7427 |
geographic |
Arctic Arctic Ocean Canadian Arctic Archipelago |
geographic_facet |
Arctic Arctic Ocean Canadian Arctic Archipelago |
genre |
Arctic Archipelago Arctic Arctic Ocean Canadian Arctic Archipelago Sea ice |
genre_facet |
Arctic Archipelago Arctic Arctic Ocean Canadian Arctic Archipelago Sea ice |
op_source |
Journal of Geophysical Research: Oceans 120 (2015): 3542-3566 doi:10.1002/2014JC010620 |
op_relation |
https://doi.org/10.1002/2014JC010620 Journal of Geophysical Research: Oceans 120 (2015): 3542-3566 https://hdl.handle.net/1912/7427 doi:10.1002/2014JC010620 |
op_doi |
https://doi.org/10.1002/2014JC010620 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
120 |
container_issue |
5 |
container_start_page |
3542 |
op_container_end_page |
3566 |
_version_ |
1766303097760514048 |