Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge
2014. American Geophysical Union. All Rights Reserved. Theory and numerical simulations suggest that topographic interactions are central to the dynamics of the Antarctic Circumpolar Current (ACC), but few observations are available to test these ideas. We use direct velocity measurements, satellite...
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ftunivtasecite:oai:ecite.utas.edu.au:97455 2023-05-15T13:37:24+02:00 Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge Rintoul, SR Sokolov, S Williams, M Pena-Molino, B Rosenberg, MA Bindoff, NL 2014 application/pdf https://doi.org/10.1002/2014GL061880 http://ecite.utas.edu.au/97455 en eng Amer Geophysical Union http://ecite.utas.edu.au/97455/1/Rintoul_2014_Macquarie_Ridge.pdf http://dx.doi.org/10.1002/2014GL061880 Rintoul, SR and Sokolov, S and Williams, M and Pena-Molino, B and Rosenberg, MA and Bindoff, NL, Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge, Geophysical Research Letters, 41, (20) pp. 7254-7261. ISSN 0094-8276 (2014) [Refereed Article] http://ecite.utas.edu.au/97455 Earth Sciences Oceanography Physical Oceanography Refereed Article PeerReviewed 2014 ftunivtasecite https://doi.org/10.1002/2014GL061880 2019-12-13T21:59:40Z 2014. American Geophysical Union. All Rights Reserved. Theory and numerical simulations suggest that topographic interactions are central to the dynamics of the Antarctic Circumpolar Current (ACC), but few observations are available to test these ideas. We use direct velocity measurements, satellite altimetry, and an ocean state estimate to investigate the interaction of the ACC with the Macquarie Ridge. Satellite altimeter data show that the Subantarctic Front crosses the ridge through a gap immediately north of Macquarie Island. Yearlong current meter records reveal strong deep mean flow (>-0.2-m-s-1 at 3000-m) and substantial transport (52 8 106-m3-s-1) in the 50-km wide gap. The ACC becomes much more barotropic at the ridge. Acceleration of the deep jet is balanced by the ageostrophic along-gap pressure gradient, convergence of zonal momentum by the mean vertical velocity, and dissipation. The study helps explain how the ACC negotiates large topographic obstacles and highlights the role of local, nonlinear processes in the dynamical balance of the ACC. Key Points Antarctic Circumpolar Current velocity was measured at Macquarie RidgeThe current becomes more barotropic as it crosses the ridgeLocal nonlinear processes accelerate deep jet Article in Journal/Newspaper Antarc* Antarctic Macquarie Island eCite UTAS (University of Tasmania) Antarctic The Antarctic Geophysical Research Letters 41 20 7254 7261 |
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eCite UTAS (University of Tasmania) |
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ftunivtasecite |
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English |
topic |
Earth Sciences Oceanography Physical Oceanography |
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Earth Sciences Oceanography Physical Oceanography Rintoul, SR Sokolov, S Williams, M Pena-Molino, B Rosenberg, MA Bindoff, NL Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge |
topic_facet |
Earth Sciences Oceanography Physical Oceanography |
description |
2014. American Geophysical Union. All Rights Reserved. Theory and numerical simulations suggest that topographic interactions are central to the dynamics of the Antarctic Circumpolar Current (ACC), but few observations are available to test these ideas. We use direct velocity measurements, satellite altimetry, and an ocean state estimate to investigate the interaction of the ACC with the Macquarie Ridge. Satellite altimeter data show that the Subantarctic Front crosses the ridge through a gap immediately north of Macquarie Island. Yearlong current meter records reveal strong deep mean flow (>-0.2-m-s-1 at 3000-m) and substantial transport (52 8 106-m3-s-1) in the 50-km wide gap. The ACC becomes much more barotropic at the ridge. Acceleration of the deep jet is balanced by the ageostrophic along-gap pressure gradient, convergence of zonal momentum by the mean vertical velocity, and dissipation. The study helps explain how the ACC negotiates large topographic obstacles and highlights the role of local, nonlinear processes in the dynamical balance of the ACC. Key Points Antarctic Circumpolar Current velocity was measured at Macquarie RidgeThe current becomes more barotropic as it crosses the ridgeLocal nonlinear processes accelerate deep jet |
format |
Article in Journal/Newspaper |
author |
Rintoul, SR Sokolov, S Williams, M Pena-Molino, B Rosenberg, MA Bindoff, NL |
author_facet |
Rintoul, SR Sokolov, S Williams, M Pena-Molino, B Rosenberg, MA Bindoff, NL |
author_sort |
Rintoul, SR |
title |
Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge |
title_short |
Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge |
title_full |
Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge |
title_fullStr |
Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge |
title_full_unstemmed |
Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge |
title_sort |
antarctic circumpolar current transport and barotropic transition at macquarie ridge |
publisher |
Amer Geophysical Union |
publishDate |
2014 |
url |
https://doi.org/10.1002/2014GL061880 http://ecite.utas.edu.au/97455 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Macquarie Island |
genre_facet |
Antarc* Antarctic Macquarie Island |
op_relation |
http://ecite.utas.edu.au/97455/1/Rintoul_2014_Macquarie_Ridge.pdf http://dx.doi.org/10.1002/2014GL061880 Rintoul, SR and Sokolov, S and Williams, M and Pena-Molino, B and Rosenberg, MA and Bindoff, NL, Antarctic Circumpolar Current transport and barotropic transition at Macquarie Ridge, Geophysical Research Letters, 41, (20) pp. 7254-7261. ISSN 0094-8276 (2014) [Refereed Article] http://ecite.utas.edu.au/97455 |
op_doi |
https://doi.org/10.1002/2014GL061880 |
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Geophysical Research Letters |
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41 |
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20 |
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7254 |
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7261 |
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1766091466035167232 |