Clean out module loads from within exrrfs_forecast.sh

[MatthewPyle-NOAA]

Buried near the end with some netCDF format conversion is this line:

if ( ! time ( module purge ; module load intel szip hdf5 netcdf nco ; module list ; set -x ; ncks -3 --64 phy_data.nc4 phy_data.nc3) ) ; then

Is this special due to needing a special version of nco? @BenjaminBlake-NOAA @hu5970 Do you know the history of why this line is here?

[BenjaminBlake-NOAA]

@MatthewPyle-NOAA I'm not really sure. It looks like it is related to converting the phy_data netcdf file from netcdf4 to netcdf3, but I wonder if this logic is still needed in exrrfs_forecast.sh or it can be removed entirely. @ShunLiu-NOAA do you know?

[ShunLiu-NOAA]

We had issues that the different NetCDF version were used for the different components (GSI, FV3 and Chgres). There was one of NetCDF version works best with FV3 for good I/O performance. Here is to ensure a consistent NetCDF format. But I don't know if we still need it after FMS lib updating.

[ShunLiu-NOAA]

Here is the issue we worked on. https://docs.google.com/presentation/d/1KjW3x8Wa91nqhGsa-nk2y44phFug56Zi8vePQ6i5pc8/edit?usp=sharing