Deep temperature variability in Drake Passage
Observations made on 21 occupations between 1993 and 2016 of GO-SHIP line SR1b in eastern Drake Passage show an average temperature of 0.53 degrees C deeper than 2000 dbar, with no significant trend, but substantial year-to-year variability (standard deviation 0.08 degrees C). Using a neutral densit...
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Online Access: | https://doi.org/10.1002/2016JC012452 https://archimer.ifremer.fr/doc/00387/49812/50390.pdf https://archimer.ifremer.fr/doc/00387/49812/ |
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fttriple:oai:gotriple.eu:10670/1.x2urwl 2023-05-15T14:03:00+02:00 Deep temperature variability in Drake Passage Firing, Yvonne L. Mcdonagh, Elaine L. King, Brian A. Desbruyeres, Damien https://doi.org/10.1002/2016JC012452 https://archimer.ifremer.fr/doc/00387/49812/50390.pdf https://archimer.ifremer.fr/doc/00387/49812/ en eng Amer Geophysical Union doi:10.1002/2016JC012452 10670/1.x2urwl https://archimer.ifremer.fr/doc/00387/49812/50390.pdf https://archimer.ifremer.fr/doc/00387/49812/ other Archimer, archive institutionnelle de l'Ifremer Journal Of Geophysical Research-oceans (2169-9275) (Amer Geophysical Union), 2017-01 , Vol. 122 , N. 1 , P. 713-725 geo envir Text https://vocabularies.coar-repositories.org/resource_types/c_18cf/ fttriple https://doi.org/10.1002/2016JC012452 2023-01-22T18:51:33Z Observations made on 21 occupations between 1993 and 2016 of GO-SHIP line SR1b in eastern Drake Passage show an average temperature of 0.53 degrees C deeper than 2000 dbar, with no significant trend, but substantial year-to-year variability (standard deviation 0.08 degrees C). Using a neutral density framework to decompose the temperature variability into isopycnal displacement (heave) and isopycnal property change components shows that approximately 95% of the year-to-year variance in deep temperature is due to heave. Changes on isopycnals make a small contribution to year-to-year variability but contribute a significant trend of -1.40.6 m degrees C per year, largest for density ((n))>28.1, south of the Polar Front (PF). The heave component is depth-coherent and results from either vertical or horizontal motions of neutral density surfaces, which trend upward and northward around the PF, downward for the densest levels in the southern section, and downward and southward in the Subantarctic Front and Southern Antarctic Circumpolar Current Front (SACCF). A proxy for the locations of the Antarctic Circumpolar Current (ACC) fronts is constructed from the repeat hydrographic data and has a strong relationship with deep ocean heat content, explaining 76% of deep temperature variance. The same frontal position proxy based on satellite altimeter-derived surface velocities explains 73% of deep temperature variance. The position of the PF plays the strongest role in this relationship between ACC fronts and deep temperature variability in Drake Passage, although much of the temperature variability in the southern half of the section can be explained by the position of the SACCF. Text Antarc* Antarctic Drake Passage Unknown Antarctic Drake Passage The Antarctic Journal of Geophysical Research: Oceans 122 1 713 725 |
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geo envir Firing, Yvonne L. Mcdonagh, Elaine L. King, Brian A. Desbruyeres, Damien Deep temperature variability in Drake Passage |
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geo envir |
description |
Observations made on 21 occupations between 1993 and 2016 of GO-SHIP line SR1b in eastern Drake Passage show an average temperature of 0.53 degrees C deeper than 2000 dbar, with no significant trend, but substantial year-to-year variability (standard deviation 0.08 degrees C). Using a neutral density framework to decompose the temperature variability into isopycnal displacement (heave) and isopycnal property change components shows that approximately 95% of the year-to-year variance in deep temperature is due to heave. Changes on isopycnals make a small contribution to year-to-year variability but contribute a significant trend of -1.40.6 m degrees C per year, largest for density ((n))>28.1, south of the Polar Front (PF). The heave component is depth-coherent and results from either vertical or horizontal motions of neutral density surfaces, which trend upward and northward around the PF, downward for the densest levels in the southern section, and downward and southward in the Subantarctic Front and Southern Antarctic Circumpolar Current Front (SACCF). A proxy for the locations of the Antarctic Circumpolar Current (ACC) fronts is constructed from the repeat hydrographic data and has a strong relationship with deep ocean heat content, explaining 76% of deep temperature variance. The same frontal position proxy based on satellite altimeter-derived surface velocities explains 73% of deep temperature variance. The position of the PF plays the strongest role in this relationship between ACC fronts and deep temperature variability in Drake Passage, although much of the temperature variability in the southern half of the section can be explained by the position of the SACCF. |
format |
Text |
author |
Firing, Yvonne L. Mcdonagh, Elaine L. King, Brian A. Desbruyeres, Damien |
author_facet |
Firing, Yvonne L. Mcdonagh, Elaine L. King, Brian A. Desbruyeres, Damien |
author_sort |
Firing, Yvonne L. |
title |
Deep temperature variability in Drake Passage |
title_short |
Deep temperature variability in Drake Passage |
title_full |
Deep temperature variability in Drake Passage |
title_fullStr |
Deep temperature variability in Drake Passage |
title_full_unstemmed |
Deep temperature variability in Drake Passage |
title_sort |
deep temperature variability in drake passage |
publisher |
Amer Geophysical Union |
url |
https://doi.org/10.1002/2016JC012452 https://archimer.ifremer.fr/doc/00387/49812/50390.pdf https://archimer.ifremer.fr/doc/00387/49812/ |
geographic |
Antarctic Drake Passage The Antarctic |
geographic_facet |
Antarctic Drake Passage The Antarctic |
genre |
Antarc* Antarctic Drake Passage |
genre_facet |
Antarc* Antarctic Drake Passage |
op_source |
Archimer, archive institutionnelle de l'Ifremer Journal Of Geophysical Research-oceans (2169-9275) (Amer Geophysical Union), 2017-01 , Vol. 122 , N. 1 , P. 713-725 |
op_relation |
doi:10.1002/2016JC012452 10670/1.x2urwl https://archimer.ifremer.fr/doc/00387/49812/50390.pdf https://archimer.ifremer.fr/doc/00387/49812/ |
op_rights |
other |
op_doi |
https://doi.org/10.1002/2016JC012452 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
122 |
container_issue |
1 |
container_start_page |
713 |
op_container_end_page |
725 |
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