Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products
This paper describes the demonstration of a regional high-resolution level-3 (L3) altimeter data unification and altimeter combination system (DUACS) developed with support from the French space agency (CNES). Deduced from full-rate (20 Hz to 40 Hz) level-2 (L2) altimeter measurements, this product...
Published in: | Remote Sensing |
---|---|
Main Authors: | , , , , , , , , , , , |
Format: | Text |
Language: | English |
Published: |
Multidisciplinary Digital Publishing Institute
2023
|
Subjects: | |
Online Access: | https://doi.org/10.3390/rs15030793 |
id |
ftmdpi:oai:mdpi.com:/2072-4292/15/3/793/ |
---|---|
record_format |
openpolar |
spelling |
ftmdpi:oai:mdpi.com:/2072-4292/15/3/793/ 2023-08-20T04:08:33+02:00 Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products Marie-Isabelle Pujol Stéphanie Dupuy Oscar Vergara Antonio Sánchez Román Yannice Faugère Pierre Prandi Mei-Ling Dabat Quentin Dagneaux Marine Lievin Emeline Cadier Gérald Dibarboure Nicolas Picot agris 2023-01-30 application/pdf https://doi.org/10.3390/rs15030793 EN eng Multidisciplinary Digital Publishing Institute Ocean Remote Sensing https://dx.doi.org/10.3390/rs15030793 https://creativecommons.org/licenses/by/4.0/ Remote Sensing; Volume 15; Issue 3; Pages: 793 altimetry mesoscale Text 2023 ftmdpi https://doi.org/10.3390/rs15030793 2023-08-01T08:33:09Z This paper describes the demonstration of a regional high-resolution level-3 (L3) altimeter data unification and altimeter combination system (DUACS) developed with support from the French space agency (CNES). Deduced from full-rate (20 Hz to 40 Hz) level-2 (L2) altimeter measurements, this product provides sea level anomalies (SLA) and other essential physical variables at a spatial resolution of one sample every ~1 km over the North Atlantic Ocean. This allows us to resolve wavelengths from ~35 km to ~55 km depending on the altimeter considered. This was made possible by recent advances in radar altimeter processing for both synthetic aperture radar (SAR) and low-resolution-mode (LRM) measurements, as well as improvements made to different stages of the DUACS processing chain. Firstly, the new adaptive and low-resolution with range migration correction (LR-RMC) processing techniques were considered for Jason and Sentinel-3 (S3A), respectively. They significantly reduce errors at short wavelengths, and the adaptive processing also reduces possible land contamination near the coast. Next, up-to-date geophysical and environmental corrections were selected for this production. This includes specific corrections intended to reduce the measurement noise on LRM measurements and thus enhance the observability at short wavelengths. Compared with the 1 Hz product, the observable wavelengths reached with the demonstration high-resolution product are reduced by up to one third, or up to half in the northeast Atlantic region. The residual noises were optimally filtered from full-rate measurements, taking into consideration the different observing capabilities of the altimeters processed. A specific data recovery strategy was applied, significantly optimizing the data availability, both in the coastal and open ocean areas. This demonstration L3 product is thus better resolved than the conventional 1 Hz product, especially near the coast, where it is defined up to ~5 km against ~10 km for the 1 Hz version. Multi-mission ... Text North Atlantic Northeast Atlantic MDPI Open Access Publishing Remote Sensing 15 3 793 |
institution |
Open Polar |
collection |
MDPI Open Access Publishing |
op_collection_id |
ftmdpi |
language |
English |
topic |
altimetry mesoscale |
spellingShingle |
altimetry mesoscale Marie-Isabelle Pujol Stéphanie Dupuy Oscar Vergara Antonio Sánchez Román Yannice Faugère Pierre Prandi Mei-Ling Dabat Quentin Dagneaux Marine Lievin Emeline Cadier Gérald Dibarboure Nicolas Picot Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products |
topic_facet |
altimetry mesoscale |
description |
This paper describes the demonstration of a regional high-resolution level-3 (L3) altimeter data unification and altimeter combination system (DUACS) developed with support from the French space agency (CNES). Deduced from full-rate (20 Hz to 40 Hz) level-2 (L2) altimeter measurements, this product provides sea level anomalies (SLA) and other essential physical variables at a spatial resolution of one sample every ~1 km over the North Atlantic Ocean. This allows us to resolve wavelengths from ~35 km to ~55 km depending on the altimeter considered. This was made possible by recent advances in radar altimeter processing for both synthetic aperture radar (SAR) and low-resolution-mode (LRM) measurements, as well as improvements made to different stages of the DUACS processing chain. Firstly, the new adaptive and low-resolution with range migration correction (LR-RMC) processing techniques were considered for Jason and Sentinel-3 (S3A), respectively. They significantly reduce errors at short wavelengths, and the adaptive processing also reduces possible land contamination near the coast. Next, up-to-date geophysical and environmental corrections were selected for this production. This includes specific corrections intended to reduce the measurement noise on LRM measurements and thus enhance the observability at short wavelengths. Compared with the 1 Hz product, the observable wavelengths reached with the demonstration high-resolution product are reduced by up to one third, or up to half in the northeast Atlantic region. The residual noises were optimally filtered from full-rate measurements, taking into consideration the different observing capabilities of the altimeters processed. A specific data recovery strategy was applied, significantly optimizing the data availability, both in the coastal and open ocean areas. This demonstration L3 product is thus better resolved than the conventional 1 Hz product, especially near the coast, where it is defined up to ~5 km against ~10 km for the 1 Hz version. Multi-mission ... |
format |
Text |
author |
Marie-Isabelle Pujol Stéphanie Dupuy Oscar Vergara Antonio Sánchez Román Yannice Faugère Pierre Prandi Mei-Ling Dabat Quentin Dagneaux Marine Lievin Emeline Cadier Gérald Dibarboure Nicolas Picot |
author_facet |
Marie-Isabelle Pujol Stéphanie Dupuy Oscar Vergara Antonio Sánchez Román Yannice Faugère Pierre Prandi Mei-Ling Dabat Quentin Dagneaux Marine Lievin Emeline Cadier Gérald Dibarboure Nicolas Picot |
author_sort |
Marie-Isabelle Pujol |
title |
Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products |
title_short |
Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products |
title_full |
Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products |
title_fullStr |
Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products |
title_full_unstemmed |
Refining the Resolution of DUACS Along-Track Level-3 Sea Level Altimetry Products |
title_sort |
refining the resolution of duacs along-track level-3 sea level altimetry products |
publisher |
Multidisciplinary Digital Publishing Institute |
publishDate |
2023 |
url |
https://doi.org/10.3390/rs15030793 |
op_coverage |
agris |
genre |
North Atlantic Northeast Atlantic |
genre_facet |
North Atlantic Northeast Atlantic |
op_source |
Remote Sensing; Volume 15; Issue 3; Pages: 793 |
op_relation |
Ocean Remote Sensing https://dx.doi.org/10.3390/rs15030793 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3390/rs15030793 |
container_title |
Remote Sensing |
container_volume |
15 |
container_issue |
3 |
container_start_page |
793 |
_version_ |
1774720875559387136 |