Comparison and validation of internal tides models for global ocean

Loren Carrere (CLS, France)

CoAuthors

Florent Lyard (LEGOS/CNRS, FRANCE); Romain Baghi (CLS, FRANCE); Nicolas Picot (CNES, FRANCE)

Event: 2017 Ocean Surface Topography Science Team Meeting

Session: Tides, internal tides and high-frequency processes

Presentation type: Type Oral

Thanks to its current accuracy and maturity, altimetry is considered as a fully operational observing system dedicated to scientific and operational applications. In order to access the targeted ocean signal, altimeter measurements are corrected for several geophysical parameters among which the ocean tide correction is one of the most critical. Global ocean and loading tide models GOT and FES are operationally used in present altimeter GDRs to remove the barotropic tide component, but the internal tides signature at the surface are not yet corrected.

Internal tides can have a signature of several cm at the surface with wavelength about 50-250 km for the first mode. The perspective of SWOT mission and high resolution ocean measurements make the correction of these small scale signals a challenge, as we need to be able to separate tides from other oceanic signals.

In 2016, a detailed comparison and validation of several internal tide models developed by different scientific teams (Egbert and Erofeeva 2015, Ray and Zaron 2016, Zaron 2016, Zhao et al. 2012, Dushaw 2015) has been presented focusing on the coherent internal tide signal for M2 and K1 frequencies; the analysis showed a significant altimeter variance reduction when using these internal tide corrections.
The purpose of the present study is to evaluate the new versions of these internal tide solutions and also to test the impact of some new models provided by B. Arbic and C. Ubelmann. The validation process is based on a statistical analysis, on a comparison to multi-missions altimetry including Jason-2, AltiKa and Cryosat-2 data, on a spectral analysis approach and we also use some in situ databases.


 

Oral presentation show times:

RoomStart DateEnd Date
Symphony Ballroom IV Thu, Oct 26 2017,09:15 Thu, Oct 26 2017,09:30
Loren Carrere
CLS
France
lcarrere@cls.fr