Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin
Antarctic Bottom Water (AABW) in the Australian Antarctic Basin has become fresher and lighter since the late 1960s, with largest changes observed near the sources of AABW. The volume of AABW with neutral density (n) > 28.30 kg m-3 decreased by 50% between 1969-1971 and 2008-2012, thinning at a r...
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Online Access: | https://doi.org/10.1002/2013GL058921 http://ecite.utas.edu.au/92515 |
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ftunivtasecite:oai:ecite.utas.edu.au:92515 2023-05-15T13:37:24+02:00 Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin van Wijk, EM Rintoul, SR 2014 https://doi.org/10.1002/2013GL058921 http://ecite.utas.edu.au/92515 en eng United States http://dx.doi.org/10.1002/2013GL058921 van Wijk, EM and Rintoul, SR, Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin, Geophysical Research Letters, 41, (5) pp. 1657-1664. ISSN 0094-8276 (2014) [Refereed Article] http://ecite.utas.edu.au/92515 Earth Sciences Oceanography Physical Oceanography Refereed Article PeerReviewed 2014 ftunivtasecite https://doi.org/10.1002/2013GL058921 2019-12-14T07:05:00Z Antarctic Bottom Water (AABW) in the Australian Antarctic Basin has become fresher and lighter since the late 1960s, with largest changes observed near the sources of AABW. The volume of AABW with neutral density (n) > 28.30 kg m-3 decreased by 50% between 1969-1971 and 2008-2012, thinning at a rate of >100 m per decade. Contraction of dense AABW was balanced primarily by expansion of water lighter than n = 28.15 kg m-3 prior to 1995 and by inflation of less dense classes of AABW after 1995. Oxygen concentrations remained unchanged in the densest AABW and increased on neutral surfaces for AABW with n > 28.31 kg m-3, between 1995 and 2011-2012, consistent with continued ventilation over this time period. The observed changes in potential temperature, salinity, density, volume, and oxygen of AABW can be accounted for by freshening of the source waters but cannot be explained by changes in formation rate alone. Key Points Freshening drives contraction of Antarctic Bottom Water (AABW) AABW has contracted by about 50% and thinned more than 100 m per decade since 1970 Small increase in oxygen on isopycnals suggests continued ventilation of AABW 2014. American Geophysical Union. All Rights Reserved. Article in Journal/Newspaper Antarc* Antarctic eCite UTAS (University of Tasmania) Antarctic Australian Antarctic Basin ENVELOPE(120.000,120.000,-60.000,-60.000) Australian-Antarctic Basin ENVELOPE(134.115,134.115,-58.800,-58.800) Geophysical Research Letters 41 5 1657 1664 |
institution |
Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Oceanography Physical Oceanography |
spellingShingle |
Earth Sciences Oceanography Physical Oceanography van Wijk, EM Rintoul, SR Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin |
topic_facet |
Earth Sciences Oceanography Physical Oceanography |
description |
Antarctic Bottom Water (AABW) in the Australian Antarctic Basin has become fresher and lighter since the late 1960s, with largest changes observed near the sources of AABW. The volume of AABW with neutral density (n) > 28.30 kg m-3 decreased by 50% between 1969-1971 and 2008-2012, thinning at a rate of >100 m per decade. Contraction of dense AABW was balanced primarily by expansion of water lighter than n = 28.15 kg m-3 prior to 1995 and by inflation of less dense classes of AABW after 1995. Oxygen concentrations remained unchanged in the densest AABW and increased on neutral surfaces for AABW with n > 28.31 kg m-3, between 1995 and 2011-2012, consistent with continued ventilation over this time period. The observed changes in potential temperature, salinity, density, volume, and oxygen of AABW can be accounted for by freshening of the source waters but cannot be explained by changes in formation rate alone. Key Points Freshening drives contraction of Antarctic Bottom Water (AABW) AABW has contracted by about 50% and thinned more than 100 m per decade since 1970 Small increase in oxygen on isopycnals suggests continued ventilation of AABW 2014. American Geophysical Union. All Rights Reserved. |
format |
Article in Journal/Newspaper |
author |
van Wijk, EM Rintoul, SR |
author_facet |
van Wijk, EM Rintoul, SR |
author_sort |
van Wijk, EM |
title |
Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin |
title_short |
Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin |
title_full |
Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin |
title_fullStr |
Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin |
title_full_unstemmed |
Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin |
title_sort |
freshening drives contraction of antarctic bottom water in the australian antarctic basin |
publisher |
United States |
publishDate |
2014 |
url |
https://doi.org/10.1002/2013GL058921 http://ecite.utas.edu.au/92515 |
long_lat |
ENVELOPE(120.000,120.000,-60.000,-60.000) ENVELOPE(134.115,134.115,-58.800,-58.800) |
geographic |
Antarctic Australian Antarctic Basin Australian-Antarctic Basin |
geographic_facet |
Antarctic Australian Antarctic Basin Australian-Antarctic Basin |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
http://dx.doi.org/10.1002/2013GL058921 van Wijk, EM and Rintoul, SR, Freshening drives contraction of Antarctic Bottom Water in the Australian Antarctic Basin, Geophysical Research Letters, 41, (5) pp. 1657-1664. ISSN 0094-8276 (2014) [Refereed Article] http://ecite.utas.edu.au/92515 |
op_doi |
https://doi.org/10.1002/2013GL058921 |
container_title |
Geophysical Research Letters |
container_volume |
41 |
container_issue |
5 |
container_start_page |
1657 |
op_container_end_page |
1664 |
_version_ |
1766091264214695936 |