Thorpex Report and Plan

Mozheng  Wei 

Report for October 2006 to September 2007:  

1.  Updated the ET codes to handle new GFS model with hybrid-sigma vertical 
   coordinate.  
 
2.  Evaluated the operational global ensemble system with new hybrid-sigma
    vertical coordinate. Studied and experimented a new rescaling scheme   
    designed for the top levels of the model. 

3.  Parallelized the ET codes to generate the initial perturbations for NCEP global
   ensemble forecast system. Computing efficiency has been increased 
   significantly. The number of ensemble members in operation has been  
   increased to 80. The resolution of model can be increased further in the next 
   implementation due to the parallelization.
 
4.  Started working on deriving the flow dependent 3-D analysis error variance 
 from GSI data assimilation system to restrain the initial ensemble  
 perturbations and rescaling. 

5.  Started looking at the analysis error variance by using the analysis fields 
 from different NWP centers.
 
Plan for October 2007 to September 2008:  

1.  Continue working on deriving the flow dependent 3-D analysis error variance 
 from GSI data assimilation system to restrain the initial ensemble    
 perturbations and rescaling. 

2.  Continue working on the analysis error variance by using the analysis data 
    obtained from different NWP centers.

3.  Cooperate with DA group to use ensemble information for constructing 
    an anisotropic flow-dependent hybrid background error covariance model to 
    improve the GSI data assimilation. Comparing the results from different 
    covariance localization techniques.

4.  Help implement ET based initial perturbations in different ensemble systems 
    at NCEP such as SREF, wave and climate ensemble forecast systems.

5.  Interact and coordinate with different groups in ensemble data assimilation 
 research funded by NOAA Thorpex.