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 FLEXINVERT

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Description:

  FLEXINVERT is a Bayesian inversion framework
  for optimizing fluxes of different atmospheric
  species (e.g. CO2, CH4, BC).

Contents:

  prep_flexpart:
     - selects (and optionally averages) observations and prepares
       flexpart runs with releases for each observation
     - flexpart grid_time output files are written per release
     - note need at least FLEXPART-v10.2

  prep_satellite: 
     - selects (and optionally averages) satellite retrievals and
       prepares flexpart releases for each retrieval and the 
       flexpart options files
     - flexpart grid_time output files are written per retrieval
       and represent the total column source receptor relationship
     - note need at least FLEXPART-v10.4beta

  prep_fluxes:
     - regrids fluxes (fluxes need to be at the same spatial 
       resolution as the flexpart grid_time files)
     - writes fluxes in a standard ncdf format required by
       FLEXINVERT

  prep_regions (optional):
     - prepares variable resolution grid for the inversion based 
       on flexpart flux sensitivities (output from prep_flexpart)
       (alternatively can provide own regions definition file)

  settings:
     - contains example SETTINGS_config and SETTINGS_files files
       for FLEXINVERT

  source:
     - source code for FLEXINVERT (for the actual inversion)

  prep_syndata:
     - prepares synthetic data for testing and OSSEs
     - uses output from a forward run and adds random
       perturbations to the prior fluxes and observations
       according to the error covariance matrices

  grid_to_ncdf:
     - extra tool (not needed for FLEXINVERT) to convert
       the binary grid_time files to NetCDF