A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean
The goal of this study is to assess the changes that have occurred during the Mid-Pleistocene Transition, an important transitional period in cryosphere evolution, by examining the siliceous microfossil record of sediments collected proximal to a major ice drainage outlet for the West Antarctic Ice...
Published in: | Marine Micropaleontology |
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Elsevier
2012
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Online Access: | http://nora.nerc.ac.uk/id/eprint/20177/ http://www.sciencedirect.com/science/article/pii/S037783981200045X |
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ftnerc:oai:nora.nerc.ac.uk:20177 2023-05-15T13:23:49+02:00 A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean Konfirst, Matthew A. Scherer, Reed P. Hillenbrand, Claus-Dieter Kuhn, Gerard 2012 http://nora.nerc.ac.uk/id/eprint/20177/ http://www.sciencedirect.com/science/article/pii/S037783981200045X unknown Elsevier Konfirst, Matthew A.; Scherer, Reed P.; Hillenbrand, Claus-Dieter orcid:0000-0003-0240-7317 Kuhn, Gerard. 2012 A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean. Marine Micropaleontology, 92-93. 40-51. https://doi.org/10.1016/j.marmicro.2012.05.001 <https://doi.org/10.1016/j.marmicro.2012.05.001> Publication - Article PeerReviewed 2012 ftnerc https://doi.org/10.1016/j.marmicro.2012.05.001 2023-02-04T19:32:43Z The goal of this study is to assess the changes that have occurred during the Mid-Pleistocene Transition, an important transitional period in cryosphere evolution, by examining the siliceous microfossil record of sediments collected proximal to a major ice drainage outlet for the West Antarctic Ice Sheet. Core PS58/254 was collected from a sediment drift on the upper continental rise in the Amundsen Sea, directly offshore from Pine Island Bay, one of the three main discharge areas for the West Antarctic Ice Sheet (WAIS). Published data on physical properties, geochemical composition, grain size and clay mineral assemblages are complemented here by a high-resolution record (sample spacing 10 cm) of the siliceous microfossil assemblages (diatoms and silicoflagellates). Between 1200 ka and 621 ka, the assemblage is relatively diverse, with Actinocyclus ingens, Thalassiothrix antarctica and Fragilariopsis kerguelensis dominating the assemblages, but diatom abundance is variable from low to barren. Additionally, the occurrence of A. ingens, Thalassiosira elliptipora and Thalassiosira fasciculata is used to confirm and further refine the existing age model and extend it back to 1200 ka. Species composition during the last ca. 621 ka is dominated by F. kerguelensis, which consistently comprises 80-90% of the assemblage. A clear relationship between diatom abundance and glacial/interglacial variability is apparent after 621 ka, which resembles the glacial-interglacial variability previously observed in other proxy data. A significant change in both sediment composition and diatom assemblages is observed at 621 ka. This change concurs with the last abundant occurrence of A. ingens and the end of the Mid-Pleistocene Transition (MPT, i.e. the onset of modern eccentricity/precession-paced glacial cycles around 650 ka). We suggest that during interglacial periods after 621 ka the Amundsen Sea Low pressure system shifted seasonally southwestwards towards the shelf and thereby increased the advection of relatively warm ... Article in Journal/Newspaper Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Pine Island Pine Island Bay Southern Ocean Natural Environment Research Council: NERC Open Research Archive Antarctic Southern Ocean Amundsen Sea West Antarctic Ice Sheet Island Bay ENVELOPE(-109.085,-109.085,59.534,59.534) Pine Island Bay ENVELOPE(-102.000,-102.000,-74.750,-74.750) Marine Micropaleontology 92-93 40 51 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
The goal of this study is to assess the changes that have occurred during the Mid-Pleistocene Transition, an important transitional period in cryosphere evolution, by examining the siliceous microfossil record of sediments collected proximal to a major ice drainage outlet for the West Antarctic Ice Sheet. Core PS58/254 was collected from a sediment drift on the upper continental rise in the Amundsen Sea, directly offshore from Pine Island Bay, one of the three main discharge areas for the West Antarctic Ice Sheet (WAIS). Published data on physical properties, geochemical composition, grain size and clay mineral assemblages are complemented here by a high-resolution record (sample spacing 10 cm) of the siliceous microfossil assemblages (diatoms and silicoflagellates). Between 1200 ka and 621 ka, the assemblage is relatively diverse, with Actinocyclus ingens, Thalassiothrix antarctica and Fragilariopsis kerguelensis dominating the assemblages, but diatom abundance is variable from low to barren. Additionally, the occurrence of A. ingens, Thalassiosira elliptipora and Thalassiosira fasciculata is used to confirm and further refine the existing age model and extend it back to 1200 ka. Species composition during the last ca. 621 ka is dominated by F. kerguelensis, which consistently comprises 80-90% of the assemblage. A clear relationship between diatom abundance and glacial/interglacial variability is apparent after 621 ka, which resembles the glacial-interglacial variability previously observed in other proxy data. A significant change in both sediment composition and diatom assemblages is observed at 621 ka. This change concurs with the last abundant occurrence of A. ingens and the end of the Mid-Pleistocene Transition (MPT, i.e. the onset of modern eccentricity/precession-paced glacial cycles around 650 ka). We suggest that during interglacial periods after 621 ka the Amundsen Sea Low pressure system shifted seasonally southwestwards towards the shelf and thereby increased the advection of relatively warm ... |
format |
Article in Journal/Newspaper |
author |
Konfirst, Matthew A. Scherer, Reed P. Hillenbrand, Claus-Dieter Kuhn, Gerard |
spellingShingle |
Konfirst, Matthew A. Scherer, Reed P. Hillenbrand, Claus-Dieter Kuhn, Gerard A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean |
author_facet |
Konfirst, Matthew A. Scherer, Reed P. Hillenbrand, Claus-Dieter Kuhn, Gerard |
author_sort |
Konfirst, Matthew A. |
title |
A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean |
title_short |
A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean |
title_full |
A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean |
title_fullStr |
A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean |
title_full_unstemmed |
A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean |
title_sort |
marine diatom record from the amundsen sea — insights into oceanographic and climatic response to the mid-pleistocene transition in the west antarctic sector of the southern ocean |
publisher |
Elsevier |
publishDate |
2012 |
url |
http://nora.nerc.ac.uk/id/eprint/20177/ http://www.sciencedirect.com/science/article/pii/S037783981200045X |
long_lat |
ENVELOPE(-109.085,-109.085,59.534,59.534) ENVELOPE(-102.000,-102.000,-74.750,-74.750) |
geographic |
Antarctic Southern Ocean Amundsen Sea West Antarctic Ice Sheet Island Bay Pine Island Bay |
geographic_facet |
Antarctic Southern Ocean Amundsen Sea West Antarctic Ice Sheet Island Bay Pine Island Bay |
genre |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Pine Island Pine Island Bay Southern Ocean |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Pine Island Pine Island Bay Southern Ocean |
op_relation |
Konfirst, Matthew A.; Scherer, Reed P.; Hillenbrand, Claus-Dieter orcid:0000-0003-0240-7317 Kuhn, Gerard. 2012 A marine diatom record from the Amundsen Sea — Insights into oceanographic and climatic response to the Mid-Pleistocene Transition in the West Antarctic sector of the Southern Ocean. Marine Micropaleontology, 92-93. 40-51. https://doi.org/10.1016/j.marmicro.2012.05.001 <https://doi.org/10.1016/j.marmicro.2012.05.001> |
op_doi |
https://doi.org/10.1016/j.marmicro.2012.05.001 |
container_title |
Marine Micropaleontology |
container_volume |
92-93 |
container_start_page |
40 |
op_container_end_page |
51 |
_version_ |
1766375597881163776 |