ENACT

ENACT: Enhanced ocean data assimilation and climate prediction   (pdf version)

Duration: January 2002 to January 2005 (3 years)      Contact:

Since January 2002, CLS has been involved in the European Project ENACT. ENACT aims to improve climate predictions on seasonal (i.e. Will next summer be warm or cold, dry or wet?) to interannual scales (Is "El Niño" around the corner?). Supported by the European Commission under the Fifth Framework Program, this project follows the recommendations from the European climate research community (EUROCILVAR). ENACT aims to set up and test new altimetric and in situ data assimilation schemes. These new schemes should allow better initialization of coupled ocean-atmosphere models used in climatic predictions.

CLS tasks:

Within ENACT, CLS is responsible for processing and distributing altimetric data. CLS also provides ongoing expertise in the interpretation and use of these data. In particular, Pierre Yves Le Traon leads the DOS team involved in :

• Production of accurate and intercalibrated multi-mission altimeter data sets.

  All altimeter data sets (1986/1989, data from GEOSAT 1992-2004, data from T/P and ERS-1/2 then Jason-1 and ENVISAT) will be fully reprocessed to provide a homogeneous, inter-calibrated and highly accurate long time series of SLA and MSLA altimeter data. In particular, improved altimetric corrections and processing algorithms will be used. In addition, near real time altimeter data sets will be produced by the SSALTO/DUACS system.

• An estimate of a global mean dynamic topography by combining the CHAMP geoid data with available in situ data and altimeter data.

  This mean dynamic topography is essential to reference SLA altimeter data and access to the oceanic general circulation.

• Inter comparison of altimetry and in-situ data (i.e. temperature and salinity profiles, tide gauges)

  These comparisons are needed to improve the joint assimilation of in situ and altimeter data.

Users:

Products delivered by ENACT are used by the Scientific Project team. Altimeter data have been also distributed in WOCE (World Ocean Circulation Experiment) and AVISO communities.

More:

• ENACT CLS: http://www.ecmwf.int/research/EU_projects/ENACT/index.html
• ENACT official website: http://www.lodyc.jussieu.fr/equipes_lodyc/ecume/CONTRIBUTION/ENACT/