Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission data
<p>This study focuses on the internal tides (ITs) off the Amazon shelf in the tropical Atlantic. It is based on 2 km horizontally gridded observations along the swaths of SWOT (Surface Water and Ocean Topography) track 20 during the calibration/validation phase (Cal/Val, 1 d orbit) from late M...
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2025-02-01
|
| Series: | Ocean Science |
| Online Access: | https://os.copernicus.org/articles/21/325/2025/os-21-325-2025.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832540895175507968 |
|---|---|
| author | M. Tchilibou L. Carrere F. Lyard C. Ubelmann G. Dibarboure E. D. Zaron B. K. Arbic |
| author_facet | M. Tchilibou L. Carrere F. Lyard C. Ubelmann G. Dibarboure E. D. Zaron B. K. Arbic |
| author_sort | M. Tchilibou |
| collection | DOAJ |
| description | <p>This study focuses on the internal tides (ITs) off the Amazon shelf in the tropical Atlantic. It is based on 2 km horizontally gridded observations along the swaths of SWOT (Surface Water and Ocean Topography) track 20 during the calibration/validation phase (Cal/Val, 1 d orbit) from late March to early July 2023. We evaluate the amplitude of M2, N2, and S2 frequencies and use the M2 atlas as an internal tide correction model for SWOT observations. Internal tide amplitudes (models or atlases) are first derived by harmonic analysis of the SWOT sea level anomaly (SLA). The estimation is improved by performing a principal component analysis before the harmonic analysis. The results compare very well with the high-resolution empirical tide (HRET) internal tide model, the reference product for internal tide corrections in altimetry observations. The coherent mode 1 and mode 2 M2 can be distinguished in the internal tide model derived from SWOT, while the higher modes with their strong SLA signature are seen mostly in the incoherent part. In comparison to HRET, the correction of SWOT observations with SWOT-based atlases may be more relevant for this track.</p> |
| format | Article |
| id | doaj-art-5dfbe909fa1b40ad90b1cd030fb524f1 |
| institution | Kabale University |
| issn | 1812-0784 1812-0792 |
| language | English |
| publishDate | 2025-02-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Ocean Science |
| spelling | doaj-art-5dfbe909fa1b40ad90b1cd030fb524f12025-02-04T12:26:24ZengCopernicus PublicationsOcean Science1812-07841812-07922025-02-012132534210.5194/os-21-325-2025Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission dataM. Tchilibou0L. Carrere1F. Lyard2C. Ubelmann3G. Dibarboure4E. D. Zaron5B. K. Arbic6Collecte Localisation Satellites (CLS), 31520 Ramonville-Saint-Agne, FranceCollecte Localisation Satellites (CLS), 31520 Ramonville-Saint-Agne, FranceUniversité de Toulouse, LEGOS (CNES/CNRS/IRD/UT3), 31400 Toulouse, FranceDatlas, Grenoble, FranceCentre National d'Etude Spatiales, 31400 Toulouse, FranceCollege of Earth, Ocean and Atmospheric Science, Oregon State University, Corvallis, OR, USADepartment of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA<p>This study focuses on the internal tides (ITs) off the Amazon shelf in the tropical Atlantic. It is based on 2 km horizontally gridded observations along the swaths of SWOT (Surface Water and Ocean Topography) track 20 during the calibration/validation phase (Cal/Val, 1 d orbit) from late March to early July 2023. We evaluate the amplitude of M2, N2, and S2 frequencies and use the M2 atlas as an internal tide correction model for SWOT observations. Internal tide amplitudes (models or atlases) are first derived by harmonic analysis of the SWOT sea level anomaly (SLA). The estimation is improved by performing a principal component analysis before the harmonic analysis. The results compare very well with the high-resolution empirical tide (HRET) internal tide model, the reference product for internal tide corrections in altimetry observations. The coherent mode 1 and mode 2 M2 can be distinguished in the internal tide model derived from SWOT, while the higher modes with their strong SLA signature are seen mostly in the incoherent part. In comparison to HRET, the correction of SWOT observations with SWOT-based atlases may be more relevant for this track.</p>https://os.copernicus.org/articles/21/325/2025/os-21-325-2025.pdf |
| spellingShingle | M. Tchilibou L. Carrere F. Lyard C. Ubelmann G. Dibarboure E. D. Zaron B. K. Arbic Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission data Ocean Science |
| title | Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission data |
| title_full | Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission data |
| title_fullStr | Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission data |
| title_full_unstemmed | Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission data |
| title_short | Internal tides off the Amazon shelf in the western tropical Atlantic: analysis of SWOT Cal/Val mission data |
| title_sort | internal tides off the amazon shelf in the western tropical atlantic analysis of swot cal val mission data |
| url | https://os.copernicus.org/articles/21/325/2025/os-21-325-2025.pdf |
| work_keys_str_mv | AT mtchilibou internaltidesofftheamazonshelfinthewesterntropicalatlanticanalysisofswotcalvalmissiondata AT lcarrere internaltidesofftheamazonshelfinthewesterntropicalatlanticanalysisofswotcalvalmissiondata AT flyard internaltidesofftheamazonshelfinthewesterntropicalatlanticanalysisofswotcalvalmissiondata AT cubelmann internaltidesofftheamazonshelfinthewesterntropicalatlanticanalysisofswotcalvalmissiondata AT gdibarboure internaltidesofftheamazonshelfinthewesterntropicalatlanticanalysisofswotcalvalmissiondata AT edzaron internaltidesofftheamazonshelfinthewesterntropicalatlanticanalysisofswotcalvalmissiondata AT bkarbic internaltidesofftheamazonshelfinthewesterntropicalatlanticanalysisofswotcalvalmissiondata |