You must have a javascript-enabled browser and javacript and stylesheets must be enabled to use some of the functions on this site.


Assimilation of altimeter data in the ECMWF ocean analysis system

Arthur Vidard(1) , Magdalena A. Balmaseda(1) , and David L. T. Anderson(1)

(1) ECMWF, Shinfield Park, RG2 9AX Reading, United Kingdom


The operational ocean analysis system at ECMWF has been recently upgraded; among other changes it includes the ability to assimilate both salinity data and sea level anomalies derived from altimeter in addition to temperature.

The altimeter data is used to correct temperature and salinity using the Cooper and Haines (1996) scheme. As part of the process of developing the new system, several ways of merging this information with the assimilation of subsurface data were explored and their respective merits compared. Additionally, attempts were made to use grace derived mean seal levels to reconstruct the total mean sea level. Although not used in the ECMWF operational system where only anomalies are assimilated, the relevance of this approach is discussed.

An ocean reanalysis was carried out from 1959 and has now reach real time. It assimilates subsurface data from 1959 and altimeter data from 1993. Results from this analysis are presented and compared with subsurface only assimilation runs.


Workshop presentation


                 Last modified: 07.10.03