Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies
Changes in Southern Ocean ventilation imprint on dissolved gases, nutrients, radiocarbon, temperature, and salinity. We deconvolve tracer measurements for the distribution, G, of times and locations of last ventilation using a maximum-entropy approach. Decadal changes of G are quantified by deconvol...
Published in: | Geophysical Research Letters |
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American Geophysical Union (AGU)
2017
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Online Access: | http://hdl.handle.net/1959.4/unsworks_45437 https://unsworks.unsw.edu.au/bitstreams/1448f18b-6c45-4ddd-b4f5-9ed9cd028d5e/download https://doi.org/10.1002/2017GL073788 |
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ftunswworks:oai:unsworks.library.unsw.edu.au:1959.4/unsworks_45437 2024-05-19T07:48:53+00:00 Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies Ting, YH Holzer, M 2017-06-16 application/pdf http://hdl.handle.net/1959.4/unsworks_45437 https://unsworks.unsw.edu.au/bitstreams/1448f18b-6c45-4ddd-b4f5-9ed9cd028d5e/download https://doi.org/10.1002/2017GL073788 unknown American Geophysical Union (AGU) http://purl.org/au-research/grants/arc/DP120100674 http://purl.org/au-research/grants/arc/DP150103067 http://hdl.handle.net/1959.4/unsworks_45437 https://unsworks.unsw.edu.au/bitstreams/1448f18b-6c45-4ddd-b4f5-9ed9cd028d5e/download https://doi.org/10.1002/2017GL073788 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:0094-8276 urn:ISSN:1944-8007 Geophysical Research Letters, 44, 11, 5655-5664 journal article http://purl.org/coar/resource_type/c_6501 2017 ftunswworks https://doi.org/10.1002/2017GL073788 2024-05-01T00:15:17Z Changes in Southern Ocean ventilation imprint on dissolved gases, nutrients, radiocarbon, temperature, and salinity. We deconvolve tracer measurements for the distribution, G, of times and locations of last ventilation using a maximum-entropy approach. Decadal changes of G are quantified by deconvolving hydrographies measured during the early 1990s and again some 15 years later. Our analysis reveals coherent changes across the five meridional sections analyzed: The fraction of water younger than 30 years decreased by ∼20% per decade south of 40°S in circumpolar deep water (CDW) and increased by ∼10% per decade north of ∼40°S in subantarctic mode water (SAMW). Ventilation locations shifted, with more water south of 40°S being ventilated north of the subantarctic front. These ventilation changes impacted CFC uptake, with concentrations south of 40°S less than (and north of 40°S higher than) expected for steady flow. The inferred changes imply increased SAMW formation and CDW upwelling consistent with strengthened westerly winds. Article in Journal/Newspaper Southern Ocean UNSW Sydney (The University of New South Wales): UNSWorks Geophysical Research Letters 44 11 5655 5664 |
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Open Polar |
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UNSW Sydney (The University of New South Wales): UNSWorks |
op_collection_id |
ftunswworks |
language |
unknown |
description |
Changes in Southern Ocean ventilation imprint on dissolved gases, nutrients, radiocarbon, temperature, and salinity. We deconvolve tracer measurements for the distribution, G, of times and locations of last ventilation using a maximum-entropy approach. Decadal changes of G are quantified by deconvolving hydrographies measured during the early 1990s and again some 15 years later. Our analysis reveals coherent changes across the five meridional sections analyzed: The fraction of water younger than 30 years decreased by ∼20% per decade south of 40°S in circumpolar deep water (CDW) and increased by ∼10% per decade north of ∼40°S in subantarctic mode water (SAMW). Ventilation locations shifted, with more water south of 40°S being ventilated north of the subantarctic front. These ventilation changes impacted CFC uptake, with concentrations south of 40°S less than (and north of 40°S higher than) expected for steady flow. The inferred changes imply increased SAMW formation and CDW upwelling consistent with strengthened westerly winds. |
format |
Article in Journal/Newspaper |
author |
Ting, YH Holzer, M |
spellingShingle |
Ting, YH Holzer, M Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies |
author_facet |
Ting, YH Holzer, M |
author_sort |
Ting, YH |
title |
Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies |
title_short |
Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies |
title_full |
Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies |
title_fullStr |
Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies |
title_full_unstemmed |
Decadal changes in Southern Ocean ventilation inferred from deconvolutions of repeat hydrographies |
title_sort |
decadal changes in southern ocean ventilation inferred from deconvolutions of repeat hydrographies |
publisher |
American Geophysical Union (AGU) |
publishDate |
2017 |
url |
http://hdl.handle.net/1959.4/unsworks_45437 https://unsworks.unsw.edu.au/bitstreams/1448f18b-6c45-4ddd-b4f5-9ed9cd028d5e/download https://doi.org/10.1002/2017GL073788 |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
urn:ISSN:0094-8276 urn:ISSN:1944-8007 Geophysical Research Letters, 44, 11, 5655-5664 |
op_relation |
http://purl.org/au-research/grants/arc/DP120100674 http://purl.org/au-research/grants/arc/DP150103067 http://hdl.handle.net/1959.4/unsworks_45437 https://unsworks.unsw.edu.au/bitstreams/1448f18b-6c45-4ddd-b4f5-9ed9cd028d5e/download https://doi.org/10.1002/2017GL073788 |
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/10.1002/2017GL073788 |
container_title |
Geophysical Research Letters |
container_volume |
44 |
container_issue |
11 |
container_start_page |
5655 |
op_container_end_page |
5664 |
_version_ |
1799467265343619072 |