Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay
Located in northwestern Hudson Bay, the Southampton Island region was identified as an Ecologically and Biologically Significant Area by Fisheries and Oceans Canada, and most recently distinguished as an Area of Interest in 2019 to become a Marine Protected Area. The region is undergoing climate-rel...
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ftunivmanitoba:oai:mspace.lib.umanitoba.ca:1993/37296 2023-08-27T04:09:18+02:00 Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay Yezhova, Yekaterina Mundy, CJ (Environment & Geography) Ehn, Jens (Environment & Geography) Kuzyk, Zou Zou (Earth Sciences) Papakyriakou, Tim 2023-03-22T15:59:59Z application/pdf http://hdl.handle.net/1993/37296 eng eng http://hdl.handle.net/1993/37296 open access Southampton Island Hudson Bay Ocean acidification Carbon Stable isotopes master thesis 2023 ftunivmanitoba 2023-08-06T17:37:06Z Located in northwestern Hudson Bay, the Southampton Island region was identified as an Ecologically and Biologically Significant Area by Fisheries and Oceans Canada, and most recently distinguished as an Area of Interest in 2019 to become a Marine Protected Area. The region is undergoing climate-related changes; however, its oceanography has received little attention until recently. The main goal of this thesis was to provide a baseline evaluation of the state of ocean acidification of these waters, and to identify key factors driving changes in both pH and calcium carbonate saturation state. Twenty-two stations were sampled around the Island in August of 2019 for salinity, stable oxygen isotope ratio of seawater, total alkalinity, dissolved inorganic carbon (DIC), and stable carbon isotope ratio of DIC (δ13CDIC), providing comprehensive water column coverage. High fractions of sea-ice melt were found in surface waters in Foxe Basin/Channel, which had experienced the most recent loss of sea ice. High fractions of meteoric water were found in near-surface waters in Roes Welcome Sound, likely from Wager Bay outflow, and south of the Island, likely from both rivers local to the Island and from Hudson Bay’s northwestern rivers. Regionally high pH, low pCO2, dissolved oxygen (O2) oversaturation, and enriched values of δ13CDIC, and thus likely areas of net primary production, were generally observed in the top ~50 m in Foxe Basin/Channel and Roes Welcome Sound, and near surface in Repulse Bay and Frozen Strait. More acidic and aragonite-undersaturated waters, potentially corrosive to marine calcifying organisms, were found below ~60 to 250 m at stations in Foxe Basin/Channel, and in bottom waters of South Bay and Evans Strait. These areas were high in pCO2 and undersaturated in O2, signifying net respiration had likely produced the observed values. It was concluded that while primary production and respiration appeared to be the dominant processes controlling the concentration of DIC in the Southampton Island region, ... Master Thesis Evans Strait Foxe Basin Frozen Strait Hudson Bay Ocean acidification Repulse Bay Roes Welcome Sound Sea ice Southampton Island Wager Bay MSpace at the University of Manitoba Hudson Bay Canada Hudson Foxe Basin ENVELOPE(-77.918,-77.918,65.931,65.931) Southampton Island ENVELOPE(-84.501,-84.501,64.463,64.463) Repulse Bay ENVELOPE(69.383,69.383,-48.883,-48.883) South Bay ENVELOPE(-63.579,-63.579,-64.870,-64.870) Frozen Strait ENVELOPE(-84.332,-84.332,65.751,65.751) Roes Welcome Sound ENVELOPE(-86.666,-86.666,65.018,65.018) Evans Strait ENVELOPE(-82.000,-82.000,63.251,63.251) |
institution |
Open Polar |
collection |
MSpace at the University of Manitoba |
op_collection_id |
ftunivmanitoba |
language |
English |
topic |
Southampton Island Hudson Bay Ocean acidification Carbon Stable isotopes |
spellingShingle |
Southampton Island Hudson Bay Ocean acidification Carbon Stable isotopes Yezhova, Yekaterina Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay |
topic_facet |
Southampton Island Hudson Bay Ocean acidification Carbon Stable isotopes |
description |
Located in northwestern Hudson Bay, the Southampton Island region was identified as an Ecologically and Biologically Significant Area by Fisheries and Oceans Canada, and most recently distinguished as an Area of Interest in 2019 to become a Marine Protected Area. The region is undergoing climate-related changes; however, its oceanography has received little attention until recently. The main goal of this thesis was to provide a baseline evaluation of the state of ocean acidification of these waters, and to identify key factors driving changes in both pH and calcium carbonate saturation state. Twenty-two stations were sampled around the Island in August of 2019 for salinity, stable oxygen isotope ratio of seawater, total alkalinity, dissolved inorganic carbon (DIC), and stable carbon isotope ratio of DIC (δ13CDIC), providing comprehensive water column coverage. High fractions of sea-ice melt were found in surface waters in Foxe Basin/Channel, which had experienced the most recent loss of sea ice. High fractions of meteoric water were found in near-surface waters in Roes Welcome Sound, likely from Wager Bay outflow, and south of the Island, likely from both rivers local to the Island and from Hudson Bay’s northwestern rivers. Regionally high pH, low pCO2, dissolved oxygen (O2) oversaturation, and enriched values of δ13CDIC, and thus likely areas of net primary production, were generally observed in the top ~50 m in Foxe Basin/Channel and Roes Welcome Sound, and near surface in Repulse Bay and Frozen Strait. More acidic and aragonite-undersaturated waters, potentially corrosive to marine calcifying organisms, were found below ~60 to 250 m at stations in Foxe Basin/Channel, and in bottom waters of South Bay and Evans Strait. These areas were high in pCO2 and undersaturated in O2, signifying net respiration had likely produced the observed values. It was concluded that while primary production and respiration appeared to be the dominant processes controlling the concentration of DIC in the Southampton Island region, ... |
author2 |
Mundy, CJ (Environment & Geography) Ehn, Jens (Environment & Geography) Kuzyk, Zou Zou (Earth Sciences) Papakyriakou, Tim |
format |
Master Thesis |
author |
Yezhova, Yekaterina |
author_facet |
Yezhova, Yekaterina |
author_sort |
Yezhova, Yekaterina |
title |
Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay |
title_short |
Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay |
title_full |
Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay |
title_fullStr |
Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay |
title_full_unstemmed |
Physical and biological controls on ocean acidification in the Southampton Island region, Hudson Bay |
title_sort |
physical and biological controls on ocean acidification in the southampton island region, hudson bay |
publishDate |
2023 |
url |
http://hdl.handle.net/1993/37296 |
long_lat |
ENVELOPE(-77.918,-77.918,65.931,65.931) ENVELOPE(-84.501,-84.501,64.463,64.463) ENVELOPE(69.383,69.383,-48.883,-48.883) ENVELOPE(-63.579,-63.579,-64.870,-64.870) ENVELOPE(-84.332,-84.332,65.751,65.751) ENVELOPE(-86.666,-86.666,65.018,65.018) ENVELOPE(-82.000,-82.000,63.251,63.251) |
geographic |
Hudson Bay Canada Hudson Foxe Basin Southampton Island Repulse Bay South Bay Frozen Strait Roes Welcome Sound Evans Strait |
geographic_facet |
Hudson Bay Canada Hudson Foxe Basin Southampton Island Repulse Bay South Bay Frozen Strait Roes Welcome Sound Evans Strait |
genre |
Evans Strait Foxe Basin Frozen Strait Hudson Bay Ocean acidification Repulse Bay Roes Welcome Sound Sea ice Southampton Island Wager Bay |
genre_facet |
Evans Strait Foxe Basin Frozen Strait Hudson Bay Ocean acidification Repulse Bay Roes Welcome Sound Sea ice Southampton Island Wager Bay |
op_relation |
http://hdl.handle.net/1993/37296 |
op_rights |
open access |
_version_ |
1775350498076917760 |