Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data
The importance of Southern Ocean sea ice has come into the focus of polar research in the last couple of decades. Especially in West Antarctica, where sea ice has declined, its distribution and evolution play a critical role for the stability of nearby ice shelves. Organic geochemical analyses of ma...
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ftcopernicus:oai:publications.copernicus.org:cpd93172 2023-05-15T13:31:40+02:00 Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data Lamping, Nele Müller, Juliane Hefter, Jens Mollenhauer, Gesine Haas, Christian Shi, Xiaoxu Vorrath, Maria-Elena Lohmann, Gerrit 2021-03-01 application/pdf https://doi.org/10.5194/cp-2021-19 https://cp.copernicus.org/preprints/cp-2021-19/ eng eng doi:10.5194/cp-2021-19 https://cp.copernicus.org/preprints/cp-2021-19/ eISSN: 1814-9332 Text 2021 ftcopernicus https://doi.org/10.5194/cp-2021-19 2021-03-08T17:22:15Z The importance of Southern Ocean sea ice has come into the focus of polar research in the last couple of decades. Especially in West Antarctica, where sea ice has declined, its distribution and evolution play a critical role for the stability of nearby ice shelves. Organic geochemical analyses of marine surface sediments from the West Antarctic continental shelves permit a biomarker-based reconstruction of sea surface conditions in these vulnerable areas. We analysed highly branched isoprenoids (HBIs), such as the sea-ice proxy IPSO 25 and phytoplankton-derived HBI-trienes, but also phytosterols and isoprenoidal glycerol dialkyl glycerol tetraethers (GDGTs), which are established tools for the reconstruction of primary productivity and sea surface temperatures, respectively. The combination of IPSO 25 with a phytoplankton marker results in the semi-quantitative sea-ice index PIPSO 25 , which provides useful reconstructions of sea-ice conditions, avoiding misleading over- or underestimations of sea-ice cover. Comparisons of the biomarker-based sea-ice distribution patterns and GDGT-based temperatures with (1) sea-ice distributions obtained from satellite observations and (2) estimated sea-ice patterns and SSTs deduced from modelled data are in reasonable agreement, but also highlight specific aspects that need to be considered when interpreting biomarker data. We further discuss IPSO 25 concentrations in the vicinity of ice shelves, where elevated values could be related to the occurrence of ice shelf basal melt water and platelet ice under landfast sea ice. Text Antarc* Antarctic Antarctica Ice Shelf Ice Shelves Sea ice Southern Ocean West Antarctica Copernicus Publications: E-Journals Antarctic Southern Ocean West Antarctica |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
The importance of Southern Ocean sea ice has come into the focus of polar research in the last couple of decades. Especially in West Antarctica, where sea ice has declined, its distribution and evolution play a critical role for the stability of nearby ice shelves. Organic geochemical analyses of marine surface sediments from the West Antarctic continental shelves permit a biomarker-based reconstruction of sea surface conditions in these vulnerable areas. We analysed highly branched isoprenoids (HBIs), such as the sea-ice proxy IPSO 25 and phytoplankton-derived HBI-trienes, but also phytosterols and isoprenoidal glycerol dialkyl glycerol tetraethers (GDGTs), which are established tools for the reconstruction of primary productivity and sea surface temperatures, respectively. The combination of IPSO 25 with a phytoplankton marker results in the semi-quantitative sea-ice index PIPSO 25 , which provides useful reconstructions of sea-ice conditions, avoiding misleading over- or underestimations of sea-ice cover. Comparisons of the biomarker-based sea-ice distribution patterns and GDGT-based temperatures with (1) sea-ice distributions obtained from satellite observations and (2) estimated sea-ice patterns and SSTs deduced from modelled data are in reasonable agreement, but also highlight specific aspects that need to be considered when interpreting biomarker data. We further discuss IPSO 25 concentrations in the vicinity of ice shelves, where elevated values could be related to the occurrence of ice shelf basal melt water and platelet ice under landfast sea ice. |
format |
Text |
author |
Lamping, Nele Müller, Juliane Hefter, Jens Mollenhauer, Gesine Haas, Christian Shi, Xiaoxu Vorrath, Maria-Elena Lohmann, Gerrit |
spellingShingle |
Lamping, Nele Müller, Juliane Hefter, Jens Mollenhauer, Gesine Haas, Christian Shi, Xiaoxu Vorrath, Maria-Elena Lohmann, Gerrit Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data |
author_facet |
Lamping, Nele Müller, Juliane Hefter, Jens Mollenhauer, Gesine Haas, Christian Shi, Xiaoxu Vorrath, Maria-Elena Lohmann, Gerrit |
author_sort |
Lamping, Nele |
title |
Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data |
title_short |
Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data |
title_full |
Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data |
title_fullStr |
Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data |
title_full_unstemmed |
Elucidating modern West Antarctic sea surface conditions: An intercomparison of lipid biomarker proxies, instrumental and numerical-model data |
title_sort |
elucidating modern west antarctic sea surface conditions: an intercomparison of lipid biomarker proxies, instrumental and numerical-model data |
publishDate |
2021 |
url |
https://doi.org/10.5194/cp-2021-19 https://cp.copernicus.org/preprints/cp-2021-19/ |
geographic |
Antarctic Southern Ocean West Antarctica |
geographic_facet |
Antarctic Southern Ocean West Antarctica |
genre |
Antarc* Antarctic Antarctica Ice Shelf Ice Shelves Sea ice Southern Ocean West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica Ice Shelf Ice Shelves Sea ice Southern Ocean West Antarctica |
op_source |
eISSN: 1814-9332 |
op_relation |
doi:10.5194/cp-2021-19 https://cp.copernicus.org/preprints/cp-2021-19/ |
op_doi |
https://doi.org/10.5194/cp-2021-19 |
_version_ |
1766020040693383168 |