Abstract's details
Toward Higher resolution Level-3 altimeter products
CoAuthors
Event: 2022 Ocean Surface Topography Science Team Meeting
Session: Science III: Mesoscale and sub-mesoscale oceanography
Presentation type: Type Poster
Contribution: PDF file
Abstract:
In 1998, first Level3 along-track, user friendly altimeter products have been developed with support from CNES and delivered to the users on AVISO+. The Level3 processing includes a homogenization of the SLA for the different altimeters (i.e. reduction of the global and regional biases), allowing the users to directly use the products without any pre-processing. They are widely used for different applications, including assimilation in numerical models. Since 2008, such products are generated and disseminated by the Copernicus Marine Service (CMEMS; previously MyOcean during its demonstration phase).
Since few years, efforts are done in order to improve the altimeter measurement in open ocean and coastal area. While the observation of the small mesoscale signal remains a challenge for the conventional altimeter measurement, new techniques and processing allow to significantly reduce the measurement errors and noises. Additionally, with the future altimeter missions as the large swath SWOT mission, the altimeter processing will face a new challenge be able to accurately process the signal at finer spatial scales.
A new generation of along-track products is under development with support from CNES (DUACS-RD project) and ESA (EO4SIBS project). They are derived from high resolution (20Hz) altimeter measurement and are specifically processed in order to solve finer scales up than the conventional 1Hz product and better sample the coastal areas. They merge recent developments that enable to optimize the Sentinel3 SAR altimeter processing (Boy 2017, Moreau,2018) and the Jason/Altika noise level (Zaron 2016, Tran 2019) and allow us to better exploit the fine-scale content of the altimetric missions. They also take into account improvements that are also done in geophysical corrections estimation (e.g. internal tide model [Zaron 2018]) and local Mean Sea Surface Estimation (e.g. Dibarboure et Pujol, 2019). Experimental datasets over European Seas and Black Sea, with a nearly 1km (5Hz) sampling, are already available on AVISO+ (https://www.aviso.altimetry.fr/duacs), CMEMS (https://marine.copernicus.eu/ ) and EO4SIBS (http://www.eo4sibs.uliege.be/). They can be tested by users. We will present these experimental 5Hz products. All the joint developments will be eventually integrated in CMEMS as part of the European regional product.
Since few years, efforts are done in order to improve the altimeter measurement in open ocean and coastal area. While the observation of the small mesoscale signal remains a challenge for the conventional altimeter measurement, new techniques and processing allow to significantly reduce the measurement errors and noises. Additionally, with the future altimeter missions as the large swath SWOT mission, the altimeter processing will face a new challenge be able to accurately process the signal at finer spatial scales.
A new generation of along-track products is under development with support from CNES (DUACS-RD project) and ESA (EO4SIBS project). They are derived from high resolution (20Hz) altimeter measurement and are specifically processed in order to solve finer scales up than the conventional 1Hz product and better sample the coastal areas. They merge recent developments that enable to optimize the Sentinel3 SAR altimeter processing (Boy 2017, Moreau,2018) and the Jason/Altika noise level (Zaron 2016, Tran 2019) and allow us to better exploit the fine-scale content of the altimetric missions. They also take into account improvements that are also done in geophysical corrections estimation (e.g. internal tide model [Zaron 2018]) and local Mean Sea Surface Estimation (e.g. Dibarboure et Pujol, 2019). Experimental datasets over European Seas and Black Sea, with a nearly 1km (5Hz) sampling, are already available on AVISO+ (https://www.aviso.altimetry.fr/duacs), CMEMS (https://marine.copernicus.eu/ ) and EO4SIBS (http://www.eo4sibs.uliege.be/). They can be tested by users. We will present these experimental 5Hz products. All the joint developments will be eventually integrated in CMEMS as part of the European regional product.