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...
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fttriple:oai:gotriple.eu:oai:doaj.org/article:34701848b44b45989f01430466abb42a 2023-05-15T13:23:57+02:00 Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene Z. A. Thomas R. T. Jones C. J. Fogwill J. Hatton A. N. Williams A. Hogg S. Mooney P. Jones D. Lister P. Mayewski C. S. M. Turney 2018-11-01 https://www.clim-past.net/14/1727/2018/cp-14-1727-2018.pdf https://doaj.org/article/34701848b44b45989f01430466abb42a en eng Copernicus Publications 1814-9324 1814-9332 https://www.clim-past.net/14/1727/2018/cp-14-1727-2018.pdf https://doaj.org/article/34701848b44b45989f01430466abb42a undefined Climate of the Past, Vol 14, Pp 1727-1738 (2018) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2018 fttriple 2023-01-22T19:11:44Z 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 Unknown Amundsen Sea Antarctic Pacific Southern Ocean The Antarctic |
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geo envir Z. A. Thomas R. T. Jones C. J. Fogwill J. Hatton A. N. Williams A. Hogg S. Mooney P. Jones D. Lister P. Mayewski C. S. M. Turney Evidence for increased expression of the Amundsen Sea Low over the South Atlantic during the late Holocene |
topic_facet |
geo envir |
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 |
Z. A. Thomas R. T. Jones C. J. Fogwill J. Hatton A. N. Williams A. Hogg S. Mooney P. Jones D. Lister P. Mayewski C. S. M. Turney |
author_facet |
Z. A. Thomas R. T. Jones C. J. Fogwill J. Hatton A. N. Williams A. Hogg S. Mooney P. Jones D. Lister P. Mayewski C. S. M. Turney |
author_sort |
Z. A. Thomas |
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 |
https://www.clim-past.net/14/1727/2018/cp-14-1727-2018.pdf https://doaj.org/article/34701848b44b45989f01430466abb42a |
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 |
Climate of the Past, Vol 14, Pp 1727-1738 (2018) |
op_relation |
1814-9324 1814-9332 https://www.clim-past.net/14/1727/2018/cp-14-1727-2018.pdf https://doaj.org/article/34701848b44b45989f01430466abb42a |
op_rights |
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