A global comparison of Argo and satellite altimetry observations
Differences, similarities and complementarities between Sea Level Anomalies (SLA) deduced from altimeter measurements and dynamic height anomalies (DHA) calculated from Argo in situ temperature (T) and salinity (S) profiles are globally analyzed. SLA and DHA agree remarkably well and, compared to pr...
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ftarchimer:oai:archimer.ifremer.fr:14630 2023-05-15T18:25:52+02:00 A global comparison of Argo and satellite altimetry observations Dhomps, A. -l. Guinehut, S. Le Traon, Pierre-yves Larnicol, Gilles 2011 application/pdf https://archimer.ifremer.fr/doc/00035/14630/11930.pdf https://doi.org/10.5194/os-7-175-2011 https://archimer.ifremer.fr/doc/00035/14630/ eng eng Copernicus Gesellschaft Mbh https://archimer.ifremer.fr/doc/00035/14630/11930.pdf doi:10.5194/os-7-175-2011 https://archimer.ifremer.fr/doc/00035/14630/ Author(s) 2011. This work is distributed under the Creative Commons Attribution 3.0 License. info:eu-repo/semantics/openAccess restricted use CC-BY Ocean Science (1812-0784) (Copernicus Gesellschaft Mbh), 2011 , Vol. 7 , N. 2 , P. 175-183 text Publication info:eu-repo/semantics/article 2011 ftarchimer https://doi.org/10.5194/os-7-175-2011 2021-09-23T20:19:23Z Differences, similarities and complementarities between Sea Level Anomalies (SLA) deduced from altimeter measurements and dynamic height anomalies (DHA) calculated from Argo in situ temperature (T) and salinity (S) profiles are globally analyzed. SLA and DHA agree remarkably well and, compared to previous studies, Argo dataset allows an improvement in the coherence between SLA and DHA. Indeed, Argo data provides a much better spatial coverage of all oceans and particularly the Southern Ocean, the use of an Argo mean dynamic height, the use of measured salinity profiles (versus climatological salinity), and the use of a deeper reference level (1000 m versus 700 m). The large influence of Argo salinity observations on the consistency between altimetry and hydrographic observations is particularly demonstrated with an improvement of 35% (relative to the SLA minus DHA signal) by using measured salinity profiles instead of climatological data. The availability of observations along the Argo float trajectories also provides a means to describe the sea level variability of the global ocean both for the low frequency and the mesoscale part of the circulation. Results indicate that sea level variability is dominated by baroclinic signal at seasonal to inter-annual periods for all latitudes. In the tropics, sea level variability is baroclinic for meso-scale to interannual periods and at high latitudes, sea level variability is barotropic with also deep baroclinic signals (i.e. influence of deep temperature and salinity signals) for intra seasonal and mesoscale periods. These results emphasize the need to separate the different time and space scales in order to improve the merging of the two data sets. The qualitative study of seasonal to interannual SLA minus DHA signals finally reveals signals related to deep ocean circulation variations and basin-scale barotropic signals. Future work is, however, needed to understand the observed differences and relate them to different forcing mechanisms. Article in Journal/Newspaper Southern Ocean Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Southern Ocean Ocean Science 7 2 175 183 |
institution |
Open Polar |
collection |
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) |
op_collection_id |
ftarchimer |
language |
English |
description |
Differences, similarities and complementarities between Sea Level Anomalies (SLA) deduced from altimeter measurements and dynamic height anomalies (DHA) calculated from Argo in situ temperature (T) and salinity (S) profiles are globally analyzed. SLA and DHA agree remarkably well and, compared to previous studies, Argo dataset allows an improvement in the coherence between SLA and DHA. Indeed, Argo data provides a much better spatial coverage of all oceans and particularly the Southern Ocean, the use of an Argo mean dynamic height, the use of measured salinity profiles (versus climatological salinity), and the use of a deeper reference level (1000 m versus 700 m). The large influence of Argo salinity observations on the consistency between altimetry and hydrographic observations is particularly demonstrated with an improvement of 35% (relative to the SLA minus DHA signal) by using measured salinity profiles instead of climatological data. The availability of observations along the Argo float trajectories also provides a means to describe the sea level variability of the global ocean both for the low frequency and the mesoscale part of the circulation. Results indicate that sea level variability is dominated by baroclinic signal at seasonal to inter-annual periods for all latitudes. In the tropics, sea level variability is baroclinic for meso-scale to interannual periods and at high latitudes, sea level variability is barotropic with also deep baroclinic signals (i.e. influence of deep temperature and salinity signals) for intra seasonal and mesoscale periods. These results emphasize the need to separate the different time and space scales in order to improve the merging of the two data sets. The qualitative study of seasonal to interannual SLA minus DHA signals finally reveals signals related to deep ocean circulation variations and basin-scale barotropic signals. Future work is, however, needed to understand the observed differences and relate them to different forcing mechanisms. |
format |
Article in Journal/Newspaper |
author |
Dhomps, A. -l. Guinehut, S. Le Traon, Pierre-yves Larnicol, Gilles |
spellingShingle |
Dhomps, A. -l. Guinehut, S. Le Traon, Pierre-yves Larnicol, Gilles A global comparison of Argo and satellite altimetry observations |
author_facet |
Dhomps, A. -l. Guinehut, S. Le Traon, Pierre-yves Larnicol, Gilles |
author_sort |
Dhomps, A. -l. |
title |
A global comparison of Argo and satellite altimetry observations |
title_short |
A global comparison of Argo and satellite altimetry observations |
title_full |
A global comparison of Argo and satellite altimetry observations |
title_fullStr |
A global comparison of Argo and satellite altimetry observations |
title_full_unstemmed |
A global comparison of Argo and satellite altimetry observations |
title_sort |
global comparison of argo and satellite altimetry observations |
publisher |
Copernicus Gesellschaft Mbh |
publishDate |
2011 |
url |
https://archimer.ifremer.fr/doc/00035/14630/11930.pdf https://doi.org/10.5194/os-7-175-2011 https://archimer.ifremer.fr/doc/00035/14630/ |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Ocean Science (1812-0784) (Copernicus Gesellschaft Mbh), 2011 , Vol. 7 , N. 2 , P. 175-183 |
op_relation |
https://archimer.ifremer.fr/doc/00035/14630/11930.pdf doi:10.5194/os-7-175-2011 https://archimer.ifremer.fr/doc/00035/14630/ |
op_rights |
Author(s) 2011. This work is distributed under the Creative Commons Attribution 3.0 License. info:eu-repo/semantics/openAccess restricted use |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/os-7-175-2011 |
container_title |
Ocean Science |
container_volume |
7 |
container_issue |
2 |
container_start_page |
175 |
op_container_end_page |
183 |
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1766207567477866496 |