Ocean Science www.ocean-sci.net 1812-0784 1812-0792 5 2 2009 10.5194/os-5-193-2009 http://www.ocean-sci.net/5/193/2009/ http://www.ocean-sci.net/5/193/2009/os-5-193-2009.html http://www.ocean-sci.net/5/193/2009/os-5-193-2009.pdf 193 201 2009-06-17 A new assessment of the error budget of global mean sea level rate estimated by satellite altimetry over 1993–2008 M. Ablain michael.ablain@cls.fr A. Cazenave G. Valladeau S. Guinehut CLS, Ramonville Saint-Agne, France LEGOS, OMP, Toulouse, France A new error budget assessment of the global Mean Sea Level (MSL) determined by TOPEX/Poseidon and Jason-1 altimeter satellites between January 1993 and June 2008 is presented using last altimeter standards. We discuss all potential errors affecting the calculation of the global MSL rate. We also compare altimetry-based sea level with tide gauge measurements over the altimetric period. 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