...

The resulting scrip file can be used for mapping with ESMF or plotting physgrid data on the native grid. 

Mapping Files

???

${tempest_root}/bin/GenerateOverlapMesh --a ${source_mesh_file} --b ${output_root}/ne30pg3.g --out overlap_mesh.nc

???

${tempest_root}/bin/GenerateOfflineMap --in_mesh ${output_root}/ne30pg3.g --out_mesh ${source_mesh_file}  --ov_mesh overlap_mesh.nc --out_map ${output_map_file} --in_type fv --in_np 1 --out_type fv --out_np 1 --out_double --mono --volumetric

???The "ncremap -P mwf" procedure encapsulates several commands to generate all the required map files for a run without the physgrid, but since these commands are specific to using the spectral element grid, we need different commands when using the physgrid. We can implement a comparable procedure in ncremap if we want by submitting a PR to the NCO repository.

The example below shows the commands needed to generate all mapping files for a tri-grid configuration with the atmosphere on the ne30pg2 grid.. 

atm_grid_file=ne30pg2.g
ocn_grid_file=ocean.oEC60to30v3.scrip.181106.nc
lnd_grid_file=SCRIPgrid_0.5x0.5_nomask_c110308.nc
atm_name=ne30pg2
ocn_name=oEC60to30v3
lnd_name=r05
alg_name=mono
map_opts='--in_type fv --in_np 1 --out_type fv --out_np 1 --out_format Classic'
date=200110
ncremap -a tempest --src_grd=$ocn_grid_file --dst_grd=$atm_grid_file -m map_${ocn_name}_to_${atm_name}_${alg_name}.${date}.nc -W $opts
ncremap -a tempest --src_grd=$atm_grid_file --dst_grd=$ocn_grid_file -m map_${atm_name}_to_${ocn_name}_${alg_name}.${date}.nc -W $opts --a2o
ncremap -a tempest --src_grd=$lnd_grid_file --dst_grd=$atm_grid_file -m map_${lnd_name}_to_${atm_name}_${alg_name}.${date}.nc -W $opts 
ncremap -a tempest --src_grd=$atm_grid_file --dst_grd=$lnd_grid_file -m map_${atm_name}_to_${lnd_name}_${alg_name}.${date}.nc -W $opts 
ncremap -a tempest --src_grd=$lnd_grid_file --dst_grd=$ocn_grid_file -m map_${lnd_name}_to_${ocn_name}_${alg_name}.${date}.nc -W $opts --a2o
ncremap -a tempest --src_grd=$ocn_grid_file --dst_grd=$lnd_grid_file -m map_${ocn_name}_to_${lnd_name}_${alg_name}.${date}.nc -W $opts 

The path to these files needs to added to the appropriate section of cime/config/e3sm/config_grids.xml.

Domain Files

No change in the procedure for generating domain files except that the physgrid grid and mapping files described above need to be used because the physics grid is used when communicating with the coupler, which is primarily where the domain files are needed. 

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