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[SIREN] Grid coincidence – Message List – Discussion – NEMO

Tools (#2) - [SIREN] Grid coincidence (#3) - Message List

[SIREN] Grid coincidence


Maybe I'm having no luck today, it seems that I do something wrong at every step.

Now that create_bathymetry.exe accepts the non-periodicity of my bathymetry data file, it could create the child bathymetry file. After that, I replaced the input bathymetry file with this one: cn_varfile='' is a subset of the 1/2-minute Gebco bathymetry, I took an area including, but larger than, my child model. I used exactly the same netcdf variables as the NEMO bathymetry that I used previously for cn_varfile:

netcdf gebco {
dimensions:  x = 2501 ; y = 1501 ;
variables: double nav_lon(y, x) ;   double nav_lat(y, x) ;  double Bathymetry(y, x) ;

With this new bathymetry file, there is a new fatal error:

FATAL   : GRID CHECK COINCIDENCE: no coincidence between fine and coarse grid:
  : invalid refinement factor

Should the bathymetry grid correspond to the parent model grid ? Or can I use just any bathymetry as long as I give nav_lon, nav_lat and Bathymetry ?

The parent model has a certain resolution, the child model ratio is 5, but the gebco bathymetry is yet another resolution.

I ask this, because there probably is no error of refinement ratio between the parent and child grids (I did not modify their coordinates, I just changed the bathymetry data file).



  • Message #5

    SIREN manage only refinment on ORCA grid.

    So your files have to be on ORCA grid. Actually maybe it coud work on regular grid (not tested yet). But to do so, your coordinates files have to be both (coarse and fine) on regular grid.

    For now SIREN, are not able to create Bathymetry from gebco or other databse.

    So you could use Bathymetry from the coarse grid. SIREN will create a refined Bathymetry on fine grid.

    Or you could use Bathymetry on ORCA grid at the fine resolution, wider than your fine grid domain. In that case SIREN will only extract Bathymetry on your fine domain.


    • Message #7


      I did not realize that SIREN works only with ORCA grids. In my case, I am not interested to just refine the coarse-grid bathymetry by interpolation, if a high-resolution bathymetry dataset is available.

      I have saved the gebco bathymetry in a Nemo-style "" file, and I have reverted to Nesting_Tools that manages Nemo bathymetry files.

      If I knew how to convert rectangular grids to an ORCA grid, I might have converted the Gebco data and used SIREN further, but I am ignorant of ORCA grids :-)

      Thank you for your help, cheers,



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