A posteriori verification of analysis and assimilation algorithms (presentation, 2001)

June 2001

Presentation of Wafaa Sadiki, Claude Fischer and Gérald Desroziers during the ALATNET training course on Data Assimilation in Gourdon, 11-22 June 2001.

A posteriori diagnostics in a variational scheme :
- improve the knowledge of the assimilation systems based on variational approach
- develop a set of diagnostics allowing to validate a posteriori, any analysis algorith
- estimate the accuracy of the observation and background error statistics, specified in entry of the assimilation system
- "Jmin" method
- iterative fixed-point approach
Test in the ALADIN 3D-Var system
- tuning of background information error parameters : Lagged-NMC statistics