These instructions are specifically for NCAR computers derecho and casper.
The following steps describe creating a new grid and using it in a beta version of CESM3. Instructions for CESM2.2 are available in the step-by-step guide.
...
> cd ${VRM_tools}/VRM_Editor/src
> module load gcc/12.2.0
> module load ncarenv/23.10
> qmake VRM_Editor.pro
> makeRunning "make" produces a lot of warning messages; that’s ok. For Linux users, with the Qt and netCDF packages installed, building the editor should be as simple as for Casper.
Correct the file Create_VRMgrid.cpp:
Change:
CommandLineDouble (MyGridYRotate ,"x_rotate" ,0.0);
To:
CommandLineDouble (MyGridYRotate ,"y_rotate" ,0.0);
Build Create_VRMgrid on Casper:
...
Modify the bold text to point to your SCRIP file, grid name, etc.
Can add option --output_data_directory to specify location of final topography file (be sure the directory already exists).
This can take several hours.
Generate CTSM (CLM) surface datasets
On derecho, use CTSM5.2 3 source code to create the needed surfdata and landuse_timeseries files. (Latest tag is good to use, as of 1/25/25 it is ctsm5.3.020).
> git clone https://github.com/ESCOMP/CTSM ctsm5.2.0073
> cd ctsm5.2.0073
> git checkout ctsm5.23.0070
> bin/git-fleximod update
...
Run the make namelist script (modify the bold text for your resolution, MESH file and your ncol for model-mesh-nx)
(npl) > /glade/work/emmons/cesm_src_derecho/ctsm5.2.007/tools/mksurfdata_esmf/gen_mksurfdata_namelist --res Nanjingres Nanjing_ne30x8 --start-year 1979 --end-year 2026 --ssp-rcp SSP3-7.0 --model-mesh /glade/work/emmons/tutorial_Nanjing/ne0np4.Nanjing.ne30x8/grids/Nanjing_ne30x8_np4_MESH.nc --model-mesh-nx 60482 --model-mesh-ny 1
This creates files like: landuse_timeseries_SSP3-7.0_1979-2026_78pfts.txt and surfdata_Nanjing_ne30x8_SSP3-7.0_1979_78pfts_c240809.namelist.
...
| Anchor | ||||
|---|---|---|---|---|
|
On Updated June 2025: On derecho, checkout a CESM3 beta tag (that uses ctsm5.2). It is recommended the source code is cloned into your work (or scratch, if necessary; you might run out of space in home) directory where sufficient storage is available. CESM3 has replaced manage_externals with git-fleximod, which requires the following commands:
...
Below, $CESMCODE refers to yourcesm3_0_beta01 directory directory.
CCS_CONFIG
1. Add an entry for your new ESMF mesh file in <cesm>/ccs_config/component_grids_nuopc.xml
...