The cold transit of Southern Ocean upwelling
The upwelling of deep waters in the Southern Ocean is a critical component of the climate system. The time and zonal mean dynamics of this circulation describe the upwelling of Circumpolar Deep Water and the downwelling of Antarctic Intermediate Water. The thermodynamic drivers of the circulation an...
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Language: | English |
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2018
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Online Access: | https://eprints.soton.ac.uk/427438/ https://eprints.soton.ac.uk/427438/1/Evans_et_al_2018_Geophysical_Research_Letters_1_.pdf |
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ftsouthampton:oai:eprints.soton.ac.uk:427438 2024-02-11T09:57:50+01:00 The cold transit of Southern Ocean upwelling Evans, Dafydd Gwyn Zika, Jan D. Naveira Garabato, Alberto C. Nurser, A. J. George 2018-12-05 text https://eprints.soton.ac.uk/427438/ https://eprints.soton.ac.uk/427438/1/Evans_et_al_2018_Geophysical_Research_Letters_1_.pdf en English eng https://eprints.soton.ac.uk/427438/1/Evans_et_al_2018_Geophysical_Research_Letters_1_.pdf Evans, Dafydd Gwyn, Zika, Jan D., Naveira Garabato, Alberto C. and Nurser, A. J. George (2018) The cold transit of Southern Ocean upwelling. Geophysical Research Letters, 45 (24). (doi:10.1029/2018GL079986 <http://dx.doi.org/10.1029/2018GL079986>). Article PeerReviewed 2018 ftsouthampton https://doi.org/10.1029/2018GL079986 2024-01-25T23:19:25Z The upwelling of deep waters in the Southern Ocean is a critical component of the climate system. The time and zonal mean dynamics of this circulation describe the upwelling of Circumpolar Deep Water and the downwelling of Antarctic Intermediate Water. The thermodynamic drivers of the circulation and their seasonal cycle play a potentially key regulatory role. Here an observationally constrained ocean model and an observation‐based seasonal climatology are analyzed from a thermodynamic perspective, to assess the diabatic processes controlling overturning in the Southern Ocean. This reveals a seasonal two‐stage cold transit in the formation of intermediate water from upwelled deep water. First, relatively warm and saline deep water is transformed into colder and fresher near‐surface winter water via wintertime mixing. Second, winter water warms to form intermediate water through summertime surface heat fluxes. The mixing‐driven pathway from deep water to winter water follows mixing lines in thermohaline coordinates indicative of nonlinear processes. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean University of Southampton: e-Prints Soton Antarctic Southern Ocean Geophysical Research Letters 45 24 |
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Open Polar |
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University of Southampton: e-Prints Soton |
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ftsouthampton |
language |
English |
description |
The upwelling of deep waters in the Southern Ocean is a critical component of the climate system. The time and zonal mean dynamics of this circulation describe the upwelling of Circumpolar Deep Water and the downwelling of Antarctic Intermediate Water. The thermodynamic drivers of the circulation and their seasonal cycle play a potentially key regulatory role. Here an observationally constrained ocean model and an observation‐based seasonal climatology are analyzed from a thermodynamic perspective, to assess the diabatic processes controlling overturning in the Southern Ocean. This reveals a seasonal two‐stage cold transit in the formation of intermediate water from upwelled deep water. First, relatively warm and saline deep water is transformed into colder and fresher near‐surface winter water via wintertime mixing. Second, winter water warms to form intermediate water through summertime surface heat fluxes. The mixing‐driven pathway from deep water to winter water follows mixing lines in thermohaline coordinates indicative of nonlinear processes. |
format |
Article in Journal/Newspaper |
author |
Evans, Dafydd Gwyn Zika, Jan D. Naveira Garabato, Alberto C. Nurser, A. J. George |
spellingShingle |
Evans, Dafydd Gwyn Zika, Jan D. Naveira Garabato, Alberto C. Nurser, A. J. George The cold transit of Southern Ocean upwelling |
author_facet |
Evans, Dafydd Gwyn Zika, Jan D. Naveira Garabato, Alberto C. Nurser, A. J. George |
author_sort |
Evans, Dafydd Gwyn |
title |
The cold transit of Southern Ocean upwelling |
title_short |
The cold transit of Southern Ocean upwelling |
title_full |
The cold transit of Southern Ocean upwelling |
title_fullStr |
The cold transit of Southern Ocean upwelling |
title_full_unstemmed |
The cold transit of Southern Ocean upwelling |
title_sort |
cold transit of southern ocean upwelling |
publishDate |
2018 |
url |
https://eprints.soton.ac.uk/427438/ https://eprints.soton.ac.uk/427438/1/Evans_et_al_2018_Geophysical_Research_Letters_1_.pdf |
geographic |
Antarctic Southern Ocean |
geographic_facet |
Antarctic Southern Ocean |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_relation |
https://eprints.soton.ac.uk/427438/1/Evans_et_al_2018_Geophysical_Research_Letters_1_.pdf Evans, Dafydd Gwyn, Zika, Jan D., Naveira Garabato, Alberto C. and Nurser, A. J. George (2018) The cold transit of Southern Ocean upwelling. Geophysical Research Letters, 45 (24). (doi:10.1029/2018GL079986 <http://dx.doi.org/10.1029/2018GL079986>). |
op_doi |
https://doi.org/10.1029/2018GL079986 |
container_title |
Geophysical Research Letters |
container_volume |
45 |
container_issue |
24 |
_version_ |
1790593375499452416 |