Abstract's details

SARAL/AltiKa range and correction data in a flat coastal environment around the Aix island sea-level observatory, France

Laurent Testut (LEGOS, Toulouse and LIENSs/Univ. La Rochelle, France)


Valérie Ballu (LIENSs/Univ. La Rochelle, France); Alvaro Santamaría-Gómez (LIENSs/Univ. La Rochelle, France); Olivier Laurain (OCA-GEOAZUR, France); Pascal Bonnefond (Observatoire de Paris - SYRTE, France); Xavier Bertin (LIENSs/Univ. La Rochelle, France); Etienne Poirier (LIENSs/Univ. La Rochelle, France)

Event: 2016 Ocean Surface Topography Science Team Meeting

Session: Regional and Global CAL/VAL for Assembling a Climate Data Record

Presentation type: Type Poster

Contribution: not provided


Satellite altimetry in coastal areas is a challenging task due to both altimeter and radiometer contamination by land. However, the ability to use satellite altimetry data as close as possible to the coast would be invaluable and would benefit numerous applications such as local sea-level monitoring or hydrodynamic modeling and coastal oceanography.
Aix island is located between the two flat elongated islands of Ré and Oléron, which define a >10km wide inlet, sufficiently large for SARAL/AltiKa altimeter to provide SSH measurements.
The Aix island sea-level observatory provides in-situ data, such as tide gauge and GPS, which can be used to validate SSH estimates and improve specific corrections. Due to the site configuration and the sheltering of Ré and Oléron islands, methods based on the extrapolation of corrections from the less-contaminated offshore zones is not adequate. In this work, we will investigate the quality of the altimeter SSB corrections by comparison with significant wave height provided by a local wave model and an offshore gauge. Waves are computed using a fully coupled modeling system, combining a 2DH circulation model and a spectral wave model that use an unstructured grid, with a spatial resolution ranging from 100 to 1000 m.
We also look at the improvement of the tropospheric delay correction when using tropospheric delay modeled from local GPS stations, with respect to using the tropospheric delay estimated from the land-contaminated radiometer.

Poster show times:

Room Start Date End Date
Grande Halle Thu, Nov 03 2016,11:00 Thu, Nov 03 2016,18:00
Laurent Testut
LEGOS, Toulouse and LIENSs/Univ. La Rochelle