Post-process and vizualize

Python

We recommend to use python (https://www.python.org/) to analyse and visualize Meso-NH outputs. The MNHPy library was developed for this purpose, and you can find an image gallery here.

Note

All the plots made in examples test cases are made with python and MNHPy.

Ncview

ncview (https://cirrus.ucsd.edu/ncview/) can be used to quickly preview the contents of a Meso-NH file.

Warning

If your netCDF files are compressed with the Zstandard compression library (by default since Meso-NH 6.0), your environment must be adapted to support them. The easiest way is to load the Meso-NH environment in the shell used to start ncview. You can do this by running the command:
```
. YOUR_PATH/MNH-V6-1-0/conf/profile_mesonh
```

Remark: as the loading of the Meso-NH environment do a module purge on most systems, you may need to load again the ncview module after this operation (if ncview is provided this way).

If you do not want to load the Meso-NH environment or if Meso-NH is not installed on your computer, you can install the hdf5plugin (available from conda) and set the HDF5_PLUGIN_PATH environment variable with the following command:
```
export HDF5_PLUGIN_PATH=$(python -c "import hdf5plugin; print(hdf5plugin.PLUGIN_PATH)")
```

Panoply

panoply (https://www.giss.nasa.gov/tools/panoply/) can be used to quickly preview the contents of a Meso-NH file.

Warning

If your netCDF files are compressed with the Zstandard compression library (by default since Meso-NH 6.0), you need to satisfy several conditions to be able to read them:

The minimum supported version of panoply is the 5.7.0.
You need to change the preferences in panoply: in the “Files” section, check “Use nj22Config.xml file to load netCDF-C library”.

Next, you need to create the file ~/.unidata/nj22Config.xml with:

<nj22Config>
   <Netcdf4Clibrary>
      <libraryPath>$NETCDFC_LIB_PATH</libraryPath>
      <libraryName>netcdf</libraryName>
      <useForReading>true</useForReading>
   </Netcdf4Clibrary>
</nj22Config>

Finally, set the NETCDFC_LIB_PATH to point to the installation of the netCDF-C library from Meso-NH (e.g. export NETCDFC_LIB_PATH=MY_MESONH_DIRECTORY/src/dir_obj$XYZ/MASTER/NETCDF-4.6.1/lib/).