Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean
An ocean data assimilation system to assimilate Argo temperature (T) and salinity (S) profiles into the HYbrid Coordinate Ocean Model (HYCOM) was constructed, implemented and evaluated for the first time in the Atlantic Ocean (78° S to 50° N and 98° W to 20° E). The system is based on the ensemble o...
Published in: | Ocean Science |
---|---|
Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2015
|
Subjects: | |
Online Access: | https://doi.org/10.5194/os-11-195-2015 https://noa.gwlb.de/receive/cop_mods_00017612 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00017567/os-11-195-2015.pdf https://os.copernicus.org/articles/11/195/2015/os-11-195-2015.pdf |
id |
ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00017612 |
---|---|
record_format |
openpolar |
spelling |
ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00017612 2023-05-15T17:35:56+02:00 Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean Mignac, D. Tanajura, C. A. S. Santana, A. N. Lima, L. N. Xie, J. 2015-02 electronic https://doi.org/10.5194/os-11-195-2015 https://noa.gwlb.de/receive/cop_mods_00017612 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00017567/os-11-195-2015.pdf https://os.copernicus.org/articles/11/195/2015/os-11-195-2015.pdf eng eng Copernicus Publications Ocean Science -- http://www.bibliothek.uni-regensburg.de/ezeit/?2183769 -- http://www.copernicus.org/EGU/os/os.html -- 1812-0792 https://doi.org/10.5194/os-11-195-2015 https://noa.gwlb.de/receive/cop_mods_00017612 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00017567/os-11-195-2015.pdf https://os.copernicus.org/articles/11/195/2015/os-11-195-2015.pdf uneingeschränkt info:eu-repo/semantics/openAccess article Verlagsveröffentlichung article Text doc-type:article 2015 ftnonlinearchiv https://doi.org/10.5194/os-11-195-2015 2022-02-08T22:53:36Z An ocean data assimilation system to assimilate Argo temperature (T) and salinity (S) profiles into the HYbrid Coordinate Ocean Model (HYCOM) was constructed, implemented and evaluated for the first time in the Atlantic Ocean (78° S to 50° N and 98° W to 20° E). The system is based on the ensemble optimal interpolation (EnOI) algorithm proposed by Xie and Zhu (2010), especially made to deal with the hybrid nature of the HYCOM vertical coordinate system with multiple steps. The Argo T–S profiles were projected to the model vertical space to create pseudo-observed layer thicknesses (Δ pobs), which correspond to the model target densities. The first step was to assimilate Δ pobs considering the sub-state vector composed by the model layer thickness (Δ p) and the baroclinic velocity components. After that, T and S were assimilated separately. Finally, T was diagnosed below the mixed layer to preserve the density of the model isopycnal layers. Five experiments were performed from 1 January 2010 to 31 December 2012: a control run without assimilation, and four assimilation runs considering the different vertical localizations of T, S and Δ p. The assimilation experiments were able to significantly improve the thermohaline structure produced by the control run. They reduced the root mean square deviation (RMSD) of T and S calculated with respect to Argo independent data in 34 and 44%, respectively, in comparison to the control run. In some regions, such as the western North Atlantic, substantial corrections in the 20 °C isotherm depth and the upper ocean heat content towards climatological states were achieved. The runs with a vertical localization of Δ p showed positive impacts in the correction of the thermohaline structure and reduced the RMSD of T (S) from 0.993 °C (0.149 psu) to 0.905 °C (0.138 psu) for the whole domain with respect to the other assimilation runs. Article in Journal/Newspaper North Atlantic Niedersächsisches Online-Archiv NOA Ocean Science 11 1 195 213 |
institution |
Open Polar |
collection |
Niedersächsisches Online-Archiv NOA |
op_collection_id |
ftnonlinearchiv |
language |
English |
topic |
article Verlagsveröffentlichung |
spellingShingle |
article Verlagsveröffentlichung Mignac, D. Tanajura, C. A. S. Santana, A. N. Lima, L. N. Xie, J. Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean |
topic_facet |
article Verlagsveröffentlichung |
description |
An ocean data assimilation system to assimilate Argo temperature (T) and salinity (S) profiles into the HYbrid Coordinate Ocean Model (HYCOM) was constructed, implemented and evaluated for the first time in the Atlantic Ocean (78° S to 50° N and 98° W to 20° E). The system is based on the ensemble optimal interpolation (EnOI) algorithm proposed by Xie and Zhu (2010), especially made to deal with the hybrid nature of the HYCOM vertical coordinate system with multiple steps. The Argo T–S profiles were projected to the model vertical space to create pseudo-observed layer thicknesses (Δ pobs), which correspond to the model target densities. The first step was to assimilate Δ pobs considering the sub-state vector composed by the model layer thickness (Δ p) and the baroclinic velocity components. After that, T and S were assimilated separately. Finally, T was diagnosed below the mixed layer to preserve the density of the model isopycnal layers. Five experiments were performed from 1 January 2010 to 31 December 2012: a control run without assimilation, and four assimilation runs considering the different vertical localizations of T, S and Δ p. The assimilation experiments were able to significantly improve the thermohaline structure produced by the control run. They reduced the root mean square deviation (RMSD) of T and S calculated with respect to Argo independent data in 34 and 44%, respectively, in comparison to the control run. In some regions, such as the western North Atlantic, substantial corrections in the 20 °C isotherm depth and the upper ocean heat content towards climatological states were achieved. The runs with a vertical localization of Δ p showed positive impacts in the correction of the thermohaline structure and reduced the RMSD of T (S) from 0.993 °C (0.149 psu) to 0.905 °C (0.138 psu) for the whole domain with respect to the other assimilation runs. |
format |
Article in Journal/Newspaper |
author |
Mignac, D. Tanajura, C. A. S. Santana, A. N. Lima, L. N. Xie, J. |
author_facet |
Mignac, D. Tanajura, C. A. S. Santana, A. N. Lima, L. N. Xie, J. |
author_sort |
Mignac, D. |
title |
Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean |
title_short |
Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean |
title_full |
Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean |
title_fullStr |
Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean |
title_full_unstemmed |
Argo data assimilation into HYCOM with an EnOI method in the Atlantic Ocean |
title_sort |
argo data assimilation into hycom with an enoi method in the atlantic ocean |
publisher |
Copernicus Publications |
publishDate |
2015 |
url |
https://doi.org/10.5194/os-11-195-2015 https://noa.gwlb.de/receive/cop_mods_00017612 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00017567/os-11-195-2015.pdf https://os.copernicus.org/articles/11/195/2015/os-11-195-2015.pdf |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
Ocean Science -- http://www.bibliothek.uni-regensburg.de/ezeit/?2183769 -- http://www.copernicus.org/EGU/os/os.html -- 1812-0792 https://doi.org/10.5194/os-11-195-2015 https://noa.gwlb.de/receive/cop_mods_00017612 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00017567/os-11-195-2015.pdf https://os.copernicus.org/articles/11/195/2015/os-11-195-2015.pdf |
op_rights |
uneingeschränkt info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/os-11-195-2015 |
container_title |
Ocean Science |
container_volume |
11 |
container_issue |
1 |
container_start_page |
195 |
op_container_end_page |
213 |
_version_ |
1766135237049319424 |