Mean Sea Surface

Types of dataset: auxiliary product
Contents: mean sea profile above T/P reference ellipsoid. This surface is available on a regular grid (1/60°x1/60°, 1 minute). Another grid provides the estimation of error fields which represent the MSS accuracy estimated through the inverse technique.
Use: geodesy, geophysics, oceanography (operational oceanography, modeling, ocean variability studies)
Description : product recovering a 20-year period (1993-2012), based on altimetry data (mean profiles, geodetic mission and SLA) from 20-year of Topex/poseidon, ERS-2 , GFO, Jason-1,Jason-2, Envisat mean profile and  data of the ERS-1, Jason-1, and Cryosat-2 geodetic phase. Click here for a schematic view of these data. The use of several missions requires to readjust all missions between them. Thus, a reference mission is chosen and other missions are adjusted with this latest (more information). 

Geographic coverage: global (from 80°S and 84°N.)
Format : netCDF-4 format
Distribution media: FTP, Gridded Data Extraction Tool
Condition of access: products delivered as stated in the licence agreement
To get an acces to the last version of MSS product, please fill in, select the given product and valid the registration form
How to cite Aviso data?

  • New Mean Sea Surface CNES CLS 2015 Focusing on the use of Geodetic Missions of Cryosat-2 and Jason-1, Oral Presentation OSTST 2016, P.Schaeffer et al.
  • The MSS CNES CLS 2015 : Presentation and assessment, poster, Living Planet Symposium 2016, P.Schaeffer et al.

Copyright : 2015-ongoing CNES-CLS

Releases of MSS


This mean sea surface follows on MSS_CNES_CLS_2011. The key points of this CNES_CLS 2015 MSS:

  • a drastic improvement of the shortest wavelengths,
  • a better correction of the oceanic variability,
  • a reduced degradation of SLA near the coast.
  • globaly, strong reduction of errors when computing SLA
  • more homogeneity of accuracy compared to the former versions
Mean Sea Surface MSS_CNES_CLS15. Credits CNES/CLS.

July 2011: New MSS_CNES_CLS2011

This mean sea surface follows on MSS_CNES_CLS_2010.  The shorter wavelengths of this new MSS were significantly improved while maintaining the capability of the optimal analysis for removing the residual effect of the ocean variability.

It has been produced in the frame of the SLOOP project, funded by CNES/SALP, aiming at improving the quality of altimetric products in open ocean.

Mean Sea Surface MSS_CNES_CLS11.


This model is affected by artifact (that affect the shortest wavelengths lower than 30 km) concerning seamounts that appear too smoothed. This was due to the behavior of the objective analysis, which tended to overestimate the residual ocean variability at the expense of the topography (static geophysical structure).

Further information: Schaeffer P. et al.: The new CNES CLS 2010 Mean Sea Surface, oral presentation at OSTST 2010 meeting (pdf, 10 MB).

Comparaison of MSS models: DTU10 (right), MSS_CNES_CLS10 (center) where the two circled seamounts are not tall enough and to the left, the next corrected MSS_CNES_CLS11 (upcoming in 2011).

2001: CLS01

This mean sea surface succeed to CLS-SHOM98.2 project.
Concerning CLS01 this is 7 years of Topex/Poseidon data, 5 years of ERS-1/2 data, 2 years of Geosat data added to ERS-1 geodetic data which were processed and homogenized in order to produce a (1/30°x1/30°) gridded map.

Mean Sea Surface CLS01.

1998: CLS_SHOM98.2

This mean sea surface was based on 3 years of data (Topex/Poseidon, ERS-1 and Geosat) combined on a (1/16°x1/16°) grid.

Mean Sea Surface CLS_Shom98.2