Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene
The Amundsen Sea Low (ASL) plays a major role in the climate and environment of Antarctica and the Southern Ocean, including surface air temperature and sea ice concentration changes. Unfortunately, a relative dearth of observational data across the Amundsen and Bellingshausen seas prior to the sate...
Published in: | Climate of the Past |
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Format: | Article in Journal/Newspaper |
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Copernicus Publications
2018
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Online Access: | http://hdl.handle.net/1959.4/unsworks_54224 https://unsworks.unsw.edu.au/bitstreams/64c12d5b-a005-4601-89d9-78c92b7800b7/download https://unsworks.unsw.edu.au/bitstreams/1e3666bd-6e97-405a-bc7d-a7b95608c76b/download https://doi.org/10.5194/cp-14-1727-2018 |
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ftunswworks:oai:unsworks.library.unsw.edu.au:1959.4/unsworks_54224 2024-06-02T07:55:01+00:00 Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene Thomas, Zoe Jones, Richard Fogwill, Chris Hatton, Jackie Williams, Alan Hogg, Alan Mooney, Scott Jones, Phillip Lister, David Mayewski, Paul Turney, Chris 2018-11-13 application/pdf http://hdl.handle.net/1959.4/unsworks_54224 https://unsworks.unsw.edu.au/bitstreams/64c12d5b-a005-4601-89d9-78c92b7800b7/download https://unsworks.unsw.edu.au/bitstreams/1e3666bd-6e97-405a-bc7d-a7b95608c76b/download https://doi.org/10.5194/cp-14-1727-2018 unknown Copernicus Publications http://hdl.handle.net/1959.4/unsworks_54224 https://unsworks.unsw.edu.au/bitstreams/64c12d5b-a005-4601-89d9-78c92b7800b7/download https://unsworks.unsw.edu.au/bitstreams/1e3666bd-6e97-405a-bc7d-a7b95608c76b/download https://doi.org/10.5194/cp-14-1727-2018 open access https://purl.org/coar/access_right/c_abf2 CC-BY-NC-ND https://creativecommons.org/licenses/by-nc-nd/4.0/ free_to_read urn:ISSN:1814-9324 urn:ISSN:1814-9332 Climate of the Past, 14, 11, 1727-1738 13 Climate Action 14 Life Below Water anzsrc-for: 0406 Physical Geography and Environmental Geoscience journal article http://purl.org/coar/resource_type/c_6501 2018 ftunswworks https://doi.org/10.5194/cp-14-1727-2018 2024-05-07T23:48:05Z The Amundsen Sea Low (ASL) plays a major role in the climate and environment of Antarctica and the Southern Ocean, including surface air temperature and sea ice concentration changes. Unfortunately, a relative dearth of observational data across the Amundsen and Bellingshausen seas prior to the satellite era (post-1979) limits our understanding of the past behaviour and impact of the ASL. The limited proxy evidence for changes in the ASL are primarily restricted to the Antarctic where ice core evidence suggests a deepening of the atmospheric pressure system during the late Holocene. However, no data have previously been reported from the northern side of the ASL. Here we report a high-resolution, multi-proxy study of a 5000-year-long peat record from the Falkland Islands, a location sensitive to contemporary ASL dynamics which modulates northerly and westerly airflow across the southwestern South Atlantic sector of the Southern Ocean. In combination with climate reanalysis, we find a marked period of wetter, colder conditions most likely the result of enhanced southerly airflow between 5000 and 2500 years ago, suggesting limited ASL influence over the region. After 2500 years ago, drier and warmer conditions were established, implying more westerly airflow and the increased projection of the ASL onto the South Atlantic. The possible role of the equatorial Pacific via atmospheric teleconnections in driving this change is discussed. Our results are in agreement with Antarctic ice core records and fjord sediments from the southern South American coast, and suggest that the Falkland Islands provide a valuable location for reconstructing high southern latitude atmospheric circulation changes on multi-decadal to millennial timescales. Article in Journal/Newspaper Amundsen Sea Antarc* Antarctic Antarctica ice core Sea ice Southern Ocean UNSW Sydney (The University of New South Wales): UNSWorks Amundsen Sea Antarctic Pacific Southern Ocean The Antarctic Climate of the Past 14 11 1727 1738 |
institution |
Open Polar |
collection |
UNSW Sydney (The University of New South Wales): UNSWorks |
op_collection_id |
ftunswworks |
language |
unknown |
topic |
13 Climate Action 14 Life Below Water anzsrc-for: 0406 Physical Geography and Environmental Geoscience |
spellingShingle |
13 Climate Action 14 Life Below Water anzsrc-for: 0406 Physical Geography and Environmental Geoscience Thomas, Zoe Jones, Richard Fogwill, Chris Hatton, Jackie Williams, Alan Hogg, Alan Mooney, Scott Jones, Phillip Lister, David Mayewski, Paul Turney, Chris Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene |
topic_facet |
13 Climate Action 14 Life Below Water anzsrc-for: 0406 Physical Geography and Environmental Geoscience |
description |
The Amundsen Sea Low (ASL) plays a major role in the climate and environment of Antarctica and the Southern Ocean, including surface air temperature and sea ice concentration changes. Unfortunately, a relative dearth of observational data across the Amundsen and Bellingshausen seas prior to the satellite era (post-1979) limits our understanding of the past behaviour and impact of the ASL. The limited proxy evidence for changes in the ASL are primarily restricted to the Antarctic where ice core evidence suggests a deepening of the atmospheric pressure system during the late Holocene. However, no data have previously been reported from the northern side of the ASL. Here we report a high-resolution, multi-proxy study of a 5000-year-long peat record from the Falkland Islands, a location sensitive to contemporary ASL dynamics which modulates northerly and westerly airflow across the southwestern South Atlantic sector of the Southern Ocean. In combination with climate reanalysis, we find a marked period of wetter, colder conditions most likely the result of enhanced southerly airflow between 5000 and 2500 years ago, suggesting limited ASL influence over the region. After 2500 years ago, drier and warmer conditions were established, implying more westerly airflow and the increased projection of the ASL onto the South Atlantic. The possible role of the equatorial Pacific via atmospheric teleconnections in driving this change is discussed. Our results are in agreement with Antarctic ice core records and fjord sediments from the southern South American coast, and suggest that the Falkland Islands provide a valuable location for reconstructing high southern latitude atmospheric circulation changes on multi-decadal to millennial timescales. |
format |
Article in Journal/Newspaper |
author |
Thomas, Zoe Jones, Richard Fogwill, Chris Hatton, Jackie Williams, Alan Hogg, Alan Mooney, Scott Jones, Phillip Lister, David Mayewski, Paul Turney, Chris |
author_facet |
Thomas, Zoe Jones, Richard Fogwill, Chris Hatton, Jackie Williams, Alan Hogg, Alan Mooney, Scott Jones, Phillip Lister, David Mayewski, Paul Turney, Chris |
author_sort |
Thomas, Zoe |
title |
Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene |
title_short |
Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene |
title_full |
Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene |
title_fullStr |
Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene |
title_full_unstemmed |
Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene |
title_sort |
evidence for increased expression of the amundsen sea low over the south atlantic during the late holocene |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
http://hdl.handle.net/1959.4/unsworks_54224 https://unsworks.unsw.edu.au/bitstreams/64c12d5b-a005-4601-89d9-78c92b7800b7/download https://unsworks.unsw.edu.au/bitstreams/1e3666bd-6e97-405a-bc7d-a7b95608c76b/download https://doi.org/10.5194/cp-14-1727-2018 |
geographic |
Amundsen Sea Antarctic Pacific Southern Ocean The Antarctic |
geographic_facet |
Amundsen Sea Antarctic Pacific Southern Ocean The Antarctic |
genre |
Amundsen Sea Antarc* Antarctic Antarctica ice core Sea ice Southern Ocean |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctica ice core Sea ice Southern Ocean |
op_source |
urn:ISSN:1814-9324 urn:ISSN:1814-9332 Climate of the Past, 14, 11, 1727-1738 |
op_relation |
http://hdl.handle.net/1959.4/unsworks_54224 https://unsworks.unsw.edu.au/bitstreams/64c12d5b-a005-4601-89d9-78c92b7800b7/download https://unsworks.unsw.edu.au/bitstreams/1e3666bd-6e97-405a-bc7d-a7b95608c76b/download https://doi.org/10.5194/cp-14-1727-2018 |
op_rights |
open access https://purl.org/coar/access_right/c_abf2 CC-BY-NC-ND https://creativecommons.org/licenses/by-nc-nd/4.0/ free_to_read |
op_doi |
https://doi.org/10.5194/cp-14-1727-2018 |
container_title |
Climate of the Past |
container_volume |
14 |
container_issue |
11 |
container_start_page |
1727 |
op_container_end_page |
1738 |
_version_ |
1800744831858769920 |