Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies
The North Water Polynya (NOW, Inuktitut: Sarvarjuaq; Kalaallisut: Pikialasorsuaq), Baffin Bay, is the largest polynya and one of the most productive regions in the Arctic. This area of thin to absent sea ice is a critical moisture source for local ice sheet sustenance and, coupled with the inflow of...
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ftcopernicus:oai:publications.copernicus.org:bg105581 2023-05-15T14:52:59+02:00 Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies Harning, David J. Holman, Brooke Woelders, Lineke Jennings, Anne E. Sepúlveda, Julio 2023-01-16 application/pdf https://doi.org/10.5194/bg-20-229-2023 https://bg.copernicus.org/articles/20/229/2023/ eng eng doi:10.5194/bg-20-229-2023 https://bg.copernicus.org/articles/20/229/2023/ eISSN: 1726-4189 Text 2023 ftcopernicus https://doi.org/10.5194/bg-20-229-2023 2023-01-23T17:22:43Z The North Water Polynya (NOW, Inuktitut: Sarvarjuaq; Kalaallisut: Pikialasorsuaq), Baffin Bay, is the largest polynya and one of the most productive regions in the Arctic. This area of thin to absent sea ice is a critical moisture source for local ice sheet sustenance and, coupled with the inflow of nutrient-rich Arctic Surface Water, supports a diverse community of Arctic fauna and indigenous people. Although paleoceanographic records provide important insight into the NOW's past behavior, it is critical that we better understand the modern functionality of paleoceanographic proxies. In this study, we analyzed lipid biomarkers, including algal highly branched isoprenoids and sterols for sea ice extent and pelagic productivity and archaeal glycerol dibiphytanyl glycerol tetraethers (GDGTs) for ocean temperature, in a set of modern surface sediment samples from within and around the NOW. In conjunction with previously published datasets, our results show that all highly branched isoprenoids exhibit strong correlations with each other and not with sterols, which suggests a spring or autumn sea ice diatom source for all highly branched isoprenoids (HBIs) rather than a combination of sea ice and open-water diatoms as seen elsewhere in the Arctic. Sterols are also highly concentrated in the NOW and exhibit statistically higher concentrations here compared to sites south of the NOW, consistent with the order of magnitude higher primary productivity observed within the NOW relative to surrounding waters in spring and summer months. Finally, our local temperature calibrations for GDGTs and OH-GDGTs reduce the uncertainty present in global temperature calibrations but also identify some additional variables that may be important in controlling their local distribution, such as nitrate availability and dissolved oxygen. Collectively, our analyses provide new insight into the utility of these lipid biomarker proxies in high-latitude settings and will help provide a refined perspective on the past development of the NOW ... Text Arctic Baffin Bay Baffin Bay Baffin Ice Sheet inuktitut kalaallisut Sea ice Copernicus Publications: E-Journals Arctic Baffin Bay Biogeosciences 20 1 229 249 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
The North Water Polynya (NOW, Inuktitut: Sarvarjuaq; Kalaallisut: Pikialasorsuaq), Baffin Bay, is the largest polynya and one of the most productive regions in the Arctic. This area of thin to absent sea ice is a critical moisture source for local ice sheet sustenance and, coupled with the inflow of nutrient-rich Arctic Surface Water, supports a diverse community of Arctic fauna and indigenous people. Although paleoceanographic records provide important insight into the NOW's past behavior, it is critical that we better understand the modern functionality of paleoceanographic proxies. In this study, we analyzed lipid biomarkers, including algal highly branched isoprenoids and sterols for sea ice extent and pelagic productivity and archaeal glycerol dibiphytanyl glycerol tetraethers (GDGTs) for ocean temperature, in a set of modern surface sediment samples from within and around the NOW. In conjunction with previously published datasets, our results show that all highly branched isoprenoids exhibit strong correlations with each other and not with sterols, which suggests a spring or autumn sea ice diatom source for all highly branched isoprenoids (HBIs) rather than a combination of sea ice and open-water diatoms as seen elsewhere in the Arctic. Sterols are also highly concentrated in the NOW and exhibit statistically higher concentrations here compared to sites south of the NOW, consistent with the order of magnitude higher primary productivity observed within the NOW relative to surrounding waters in spring and summer months. Finally, our local temperature calibrations for GDGTs and OH-GDGTs reduce the uncertainty present in global temperature calibrations but also identify some additional variables that may be important in controlling their local distribution, such as nitrate availability and dissolved oxygen. Collectively, our analyses provide new insight into the utility of these lipid biomarker proxies in high-latitude settings and will help provide a refined perspective on the past development of the NOW ... |
format |
Text |
author |
Harning, David J. Holman, Brooke Woelders, Lineke Jennings, Anne E. Sepúlveda, Julio |
spellingShingle |
Harning, David J. Holman, Brooke Woelders, Lineke Jennings, Anne E. Sepúlveda, Julio Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies |
author_facet |
Harning, David J. Holman, Brooke Woelders, Lineke Jennings, Anne E. Sepúlveda, Julio |
author_sort |
Harning, David J. |
title |
Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies |
title_short |
Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies |
title_full |
Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies |
title_fullStr |
Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies |
title_full_unstemmed |
Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies |
title_sort |
biomarker characterization of the north water polynya, baffin bay: implications for local sea ice and temperature proxies |
publishDate |
2023 |
url |
https://doi.org/10.5194/bg-20-229-2023 https://bg.copernicus.org/articles/20/229/2023/ |
geographic |
Arctic Baffin Bay |
geographic_facet |
Arctic Baffin Bay |
genre |
Arctic Baffin Bay Baffin Bay Baffin Ice Sheet inuktitut kalaallisut Sea ice |
genre_facet |
Arctic Baffin Bay Baffin Bay Baffin Ice Sheet inuktitut kalaallisut Sea ice |
op_source |
eISSN: 1726-4189 |
op_relation |
doi:10.5194/bg-20-229-2023 https://bg.copernicus.org/articles/20/229/2023/ |
op_doi |
https://doi.org/10.5194/bg-20-229-2023 |
container_title |
Biogeosciences |
container_volume |
20 |
container_issue |
1 |
container_start_page |
229 |
op_container_end_page |
249 |
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1766324398083538944 |