Saving the post processed file in NetCDF format instead of GRIB2?

[natalie-perlin]

Is it possible to configure the run_post workflow task and to save component model output in NetCDF format, and not GRIB2?

[gspetro-NOAA]

More context from @natalie-perlin:

My underlying question was whether the UFS_WM saves the output netcdf files with horizontal wind components on a rotated grid (aligned with model orientation of X, Y), or on natural lat/lon grid... There is no any info about this, neither in UFS documentation, nor in SRW. ChatGPT says it's on a rotated grid, which needs to be transformed into the true-north... but I don't trust it!!
The post-processed files (which are in grib2) are meant to contain " true north" horiz. wind components . However, I do not see any information in WM-saved output *.nc files of an additional variable ("angle," or "grid_angle", or "alpha", or "rotation" or anything of this kind) needed to do the transformation from model grid coordinate to true north. And neither I could find any transformation done to U and V components in the UPP code itself.
So the bottom line, by the tactics of eliminations, the weather-model output in netcdf files has to have U, V components on the true-north. Thus, the UPP may not be needed in the first place to have the data analyzed, which is easier to do using *.nc files than *grib2 files.
Converting the output into grib2 files might be needed if this needs to be used as boundary conditions for another model, or else...

[gspetro-NOAA]

@natalie-perlin I just discussed with the UPP code management team, and they confirmed that UPP can ingest netCDF data, but it can only output grib2 data, so the run_post tasks in SRW will only be able to output grib2 files. They suggested that you check w/UFS WM developers to see if U and V components are saved as Earth-relative or grid-relative. They are not sure what the default is.