[en] Satellite altimetry measurements from SARAL-AltiKa are analysed in the coastal ocean using the results of the G-AltiKa mission (1–5 August 2013), which combined altimeter, HF radar and glider data coincident with the satellite track, south-west of Ibiza Island, in the Western Mediterranean Sea.
The absolute dynamic topography, computed from 1 Hz and 40 Hz altimetry data, and the dynamic height, computed from glider temperature and salinity, both exhibited a weak signal with amplitudes of order 2 cm. The resulting geostrophic and HF radar velocities along the track depicted a north-westward coastal current with a maximal velocity larger than 20 cm s−1.
This demonstrates that the AltiKa altimeter is able to resolve SLA signals of more than 2 cm, and gradients in those signals over several tens of kilometres. After filtering, the 40 Hz data depicted a signal consistent with the other platforms, up to a distance of order 10 km from the coast.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Troupin, Charles ; Mediterranean Institute for Advanced Studies (IMEDEA), Esporles, Spain
Pascual, Ananda; Mediterranean Institute for Advanced Studies (IMEDEA)
Valladeau, Guillaume
Pujol, Isabelle
Lana, Arantxa
Heslop, Emma
Ruiz, Simón
Torner, Marc
Picot, Nicolas
Tintoré, Joaquín
Language :
English
Title :
Illustration of the emerging capabilities of SARAL/AltiKa in the coastal zone using a multi-platform approach
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