Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean
[eng] The returning limb of Atlantic Meridional Overturning Circulation (AMOC) is partly supplied by the cold-fresh waters that enter through the Drake Passage. Up to the isoneutral 28.0 kg m−3, the mean water inflow through the Drake Passage to the Scotia Sea is 140.8 ± 7.4 Sv and the outflow throu...
Main Author: | |
---|---|
Other Authors: | , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | English |
Published: |
Universitat de Barcelona
2023
|
Subjects: | |
Online Access: | http://hdl.handle.net/2445/196003 http://hdl.handle.net/10803/687987 |
id |
ftubarcepubl:oai:diposit.ub.edu:2445/196003 |
---|---|
record_format |
openpolar |
spelling |
ftubarcepubl:oai:diposit.ub.edu:2445/196003 2024-02-11T10:03:24+01:00 Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean Olivé Abelló, Anna Pelegrí, J. L. Machín Jiménez, Francisco Universitat de Barcelona. Facultat de Ciències de la Terra 2023-03-20 328 p. application/pdf http://hdl.handle.net/2445/196003 http://hdl.handle.net/10803/687987 eng eng Universitat de Barcelona Tesis Doctorals - Facultat - Ciències de la Terra http://hdl.handle.net/2445/196003 http://hdl.handle.net/10803/687987 cc by-sa (c) Olivé Abelló, Anna, 2023 http://creativecommons.org/licenses/by-sa/3.0/es/ info:eu-repo/semantics/openAccess Oceanografia Circulació oceànica Corrents marins Atlàntic Oceà Oceanography Ocean circulation Ocean currents Atlantic Ocean info:eu-repo/semantics/doctoralThesis info:eu-repo/semantics/publishedVersion 2023 ftubarcepubl 2024-01-24T01:19:57Z [eng] The returning limb of Atlantic Meridional Overturning Circulation (AMOC) is partly supplied by the cold-fresh waters that enter through the Drake Passage. Up to the isoneutral 28.0 kg m−3, the mean water inflow through the Drake Passage to the Scotia Sea is 140.8 ± 7.4 Sv and the outflow through the Northern Passages is 115.9 ± 8.3 Sv. Below this isoneutral reference and down to 2000 m, an additional 23.4 Sv enters through the Drake Passage. The mean barotropic contribution always represents over half the total transports, with substantial seasonal and moderate interannual variability in the water transports. The water mean-residence time is about 6 - 8 months. Combining the Argo floats data with other observational measurements, we apply a climatological high-resolution inverse model over the Scotia Sea boundaries up to the 28.0 kg m-3 isoneutral. The ACC enters 136.7 ± 1.0 Sv through the Drake Passage and exits 137.9 ± 1.0 Sv through the northern boundary, with the difference responding to the South Scotia Ridge and Philip Passages contributions. Along its northward path, the ACC waters lose heat but gain equatorward freshwater transport. Within the Scotia Sea, the surface-modal and modal-intermediate waters experience production in all biogeochemical variables. Finally, regarding anthropogenic DIC, the Scotia Sea stores 0.123 Pg C yr-1. Then, the ROD method compares actual drifters' displacements with numerical trajectory predictions; the observed-predicted differences in final positions respond to diffusive motions not captured by the numerical models. The ROD method is applied in the western South Atlantic Ocean leading to maximum diffusivities of 4630 - 4980 m2 s-1 in the upper 200 m of the water column, presenting an inverse relationship with depth. The diffusivities near the surface are fairly constant in latitude but the diffusion coefficients at 1000 m decrease considerably south of the Southern Boundary. With the horizontal diffusion coefficients obtained previously, we use the Lagrangian ... Doctoral or Postdoctoral Thesis Drake Passage Scotia Sea South Atlantic Ocean Southern Ocean Dipòsit Digital de la Universitat de Barcelona Drake Passage Scotia Sea South Scotia Ridge ENVELOPE(-46.500,-46.500,-60.000,-60.000) Southern Ocean |
institution |
Open Polar |
collection |
Dipòsit Digital de la Universitat de Barcelona |
op_collection_id |
ftubarcepubl |
language |
English |
topic |
Oceanografia Circulació oceànica Corrents marins Atlàntic Oceà Oceanography Ocean circulation Ocean currents Atlantic Ocean |
spellingShingle |
Oceanografia Circulació oceànica Corrents marins Atlàntic Oceà Oceanography Ocean circulation Ocean currents Atlantic Ocean Olivé Abelló, Anna Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean |
topic_facet |
Oceanografia Circulació oceànica Corrents marins Atlàntic Oceà Oceanography Ocean circulation Ocean currents Atlantic Ocean |
description |
[eng] The returning limb of Atlantic Meridional Overturning Circulation (AMOC) is partly supplied by the cold-fresh waters that enter through the Drake Passage. Up to the isoneutral 28.0 kg m−3, the mean water inflow through the Drake Passage to the Scotia Sea is 140.8 ± 7.4 Sv and the outflow through the Northern Passages is 115.9 ± 8.3 Sv. Below this isoneutral reference and down to 2000 m, an additional 23.4 Sv enters through the Drake Passage. The mean barotropic contribution always represents over half the total transports, with substantial seasonal and moderate interannual variability in the water transports. The water mean-residence time is about 6 - 8 months. Combining the Argo floats data with other observational measurements, we apply a climatological high-resolution inverse model over the Scotia Sea boundaries up to the 28.0 kg m-3 isoneutral. The ACC enters 136.7 ± 1.0 Sv through the Drake Passage and exits 137.9 ± 1.0 Sv through the northern boundary, with the difference responding to the South Scotia Ridge and Philip Passages contributions. Along its northward path, the ACC waters lose heat but gain equatorward freshwater transport. Within the Scotia Sea, the surface-modal and modal-intermediate waters experience production in all biogeochemical variables. Finally, regarding anthropogenic DIC, the Scotia Sea stores 0.123 Pg C yr-1. Then, the ROD method compares actual drifters' displacements with numerical trajectory predictions; the observed-predicted differences in final positions respond to diffusive motions not captured by the numerical models. The ROD method is applied in the western South Atlantic Ocean leading to maximum diffusivities of 4630 - 4980 m2 s-1 in the upper 200 m of the water column, presenting an inverse relationship with depth. The diffusivities near the surface are fairly constant in latitude but the diffusion coefficients at 1000 m decrease considerably south of the Southern Boundary. With the horizontal diffusion coefficients obtained previously, we use the Lagrangian ... |
author2 |
Pelegrí, J. L. Machín Jiménez, Francisco Universitat de Barcelona. Facultat de Ciències de la Terra |
format |
Doctoral or Postdoctoral Thesis |
author |
Olivé Abelló, Anna |
author_facet |
Olivé Abelló, Anna |
author_sort |
Olivé Abelló, Anna |
title |
Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean |
title_short |
Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean |
title_full |
Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean |
title_fullStr |
Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean |
title_full_unstemmed |
Transformations and pathways of Southern Ocean waters into the South Atlantic Ocean |
title_sort |
transformations and pathways of southern ocean waters into the south atlantic ocean |
publisher |
Universitat de Barcelona |
publishDate |
2023 |
url |
http://hdl.handle.net/2445/196003 http://hdl.handle.net/10803/687987 |
long_lat |
ENVELOPE(-46.500,-46.500,-60.000,-60.000) |
geographic |
Drake Passage Scotia Sea South Scotia Ridge Southern Ocean |
geographic_facet |
Drake Passage Scotia Sea South Scotia Ridge Southern Ocean |
genre |
Drake Passage Scotia Sea South Atlantic Ocean Southern Ocean |
genre_facet |
Drake Passage Scotia Sea South Atlantic Ocean Southern Ocean |
op_relation |
Tesis Doctorals - Facultat - Ciències de la Terra http://hdl.handle.net/2445/196003 http://hdl.handle.net/10803/687987 |
op_rights |
cc by-sa (c) Olivé Abelló, Anna, 2023 http://creativecommons.org/licenses/by-sa/3.0/es/ info:eu-repo/semantics/openAccess |
_version_ |
1790599618273214464 |