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 FLEXINVERT-Plus

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

Contents:
  1) prep_flexpart:
     - selects (and optionally averages) observations and prepares
       flexpart runs with releases for each observation
     - flexpart grid_time output files written per release
     - note need FLEXPART-v10.2beta
  2) 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-Plus
  3) 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)
  4) settings:
     - contains example SETTINGS_config and SETTINGS_files files
       for FLEXINVERT-Plus
  5) source:
     - source code for FLEXINVERT-Plus
  6) prep_syndata:
     - prepares synthetic data for testing and OSEs
     - uses output from a forward run and adds random
       perturbations to the prior fluxes and observations
       according to the error covariance matrices
  7) grid_to_ncdf:
     - extra tool (not needed for FLEXINVERT-Plus) to convert
       the binary grid_time files to NetCDF
  
Testing environment:
  Basic test data are provided for four example cases, for both 
  a CH4 and a CO2 inversion and both with and without a nested
  domain. The SETTINGS and FLUXES configuration files are 
  provided for the examples and only need to be editted for the 
  root directory. Note to run the tests the user has to provide 
  meteo data for FLEXPART (these are not included).

TEST_INPUT:
  1) FLEXPART:
     - directory where FLEXPART options files etc are written
     - used in "prep_flexpart"
  2) OBS:
     - directory containing raw observation files
     - used in "prep_flexpart"
  3) FLUXES:
     - directory containing raw flux files
     - used in "prep_fluxes"

TEST_OUTPUT:
  1) FLEXOUT:
     - directory where FLEXPART grid_time and grid_initial 
       files are written (in step "prep_flexpart")
  2) OBS:
     - directory where processed observations are written
       (in step "prep_flexpart")
  3) FLUXES
     - directory where processed fluxes are written
       (in step "prep_fluxes")
  4) RESULTS
     - directory where inversion output are written