Library of Regionally-Refined Model (RRM) Grids

This page collects well-tested RRM configurations produced for E3SM which others might want to use.

Adding a New Grid to a Branch

General instructions for creating new grids are at https://acme-climate.atlassian.net/wiki/spaces/DOC/pages/872579110 , which also include specific instructions for RRM.

Atmosphere grids have a grid quality metric which measure the element distortion (see https://acme-climate.atlassian.net/wiki/spaces/DOC/pages/872579110). A high quality RRM grid with smooth transition region will have a value <= 4.

New grids require many modified input files, most crucially is the initial condition files. Ideally, these files should be created from a a very long run (several decades) to allow full adjustment of things like soil moisture and ozone. spun-up land conditions can be generated efficiently using the ICRUELM compset.

Creating a Pull Request to Add a New Grid to the Master Branch

The steps below are for making grids available to other users, which is especially important if your RRM grid was used in a publication. Do not create a PR if you have not thoroughly tested your new RRM grid.

Add a row for your new grid in the appropriate table below
Add the grid files to inputdata/share/meshes following the directions at https://acme-climate.atlassian.net/wiki/spaces/ED/pages/707002387.
Create a pull request making your grid available. The changes should be limited to what is needed to support the new grid as outlined below.
Modify cime_config/config_grids.xml to define the new grid
Modify cime_config/config_grids.xml to specify domain file paths
Modify cime_config/config_grids.xml to specify mapping file paths (only for bi- and tri-grid)
Modify components/eam/bld/config_files/horiz_grid.xml to specify the number of columns
Modify components/eam/bld/namelist_files/namelist_defaults_eam.xml to specify namelist defaults specific to the new grid. Typically values that need new defaults are:
1. ncdata - the atmospheric initial condition
2. bnd_topo - topography
3. drydep_srf_file surface dry deposition of aerosols (MAM)
4. mesh_file - grid definition file in exodus format
5. se_ne - set to zero for RRM
6. dtime - dynamics/physics coupling interval
For certain configurations, especially the older preqx dycor option, you may need to modify the following parameters in components/eam/bld/namelist_files/namelist_defaults_eam.xml
1. se_tstep
2. nu
3. nu_top
4. nu_div
5. hypervis_scaling
6. hypervis_subcycle_tom
7. hypervis_subcycle
Modify components/clm/bld/namelist_files/namelist_defaults_clm4_5.xml to specify land input files needed for the new grid (may not be needed for scenarios that do modify the land grid)
1. finidat - land model initial condition
2. fsurdat - input data describing surface types
Optional - modify cime/config/e3sm/allactive/config_pesall.xml to add a new PE layout for your grid
Optional - modify cime_config/tests.py to add a test for the new grid. RRM tests should only be added to specific test suites, such as e3sm_rrm.

Quasi-Uniform cubed-sphere grids (for reference)

Grid	Grid metrics

Grid	Grid metrics
1 degree (NE=30)	Max Dinv-based element distortion: 1.73 area based dx: min,max=95 km, 111 km
1/4 degree (NE=120)	Max Dinv-based element distortion: 1.73 area based dx: min,max=23 km, 28 km
3.25 km (NE=1024)	Max Dinv-based element distortion: 1.73 area based dx: min,max=2.74 km, 3.26 km

Conventional High-Resolution Grids

Grid Name	Target Fine Resolution	Target Coarse Resolution	Goals in mesh creation	Link to mesh graphic	Grid metrics	Validation	Contact Person

Grid Name	Target Fine Resolution	Target Coarse Resolution	Goals in mesh creation	Link to mesh graphic	Grid metrics	Validation	Contact Person
v2 North American RRM northamericax4v1.g	atm/land: 25 km (ne120) ocean/ice: 14 km	atm/land: 100 km (ne30) ocean/ice: 60 km		See figures in the paper	Max Dinv-based elem distortion: 3.76 area based dx: min=17 km max=117 km	Described in Tang et al., (GMDD 2022)	@Qi Tang
v2 Antarctic RRM antarcticax4v1.g	atm/land: 25 km (ne120)	atm/land: 100 km (ne30)			Max Dinv-based elem distortion: 3.25 area based dx: min=21 km max=111 km	TBD	@Qi Tang@Wuyin Lin
CONUS Extremes-Optimized RRM (HyperFACETS) ne0np4natlanticref.ne30x4.g (???) Not on E3SM inputdata server	atm/land: 25 km (ne120)	atm/land: 100 km (ne30)	28km over CONUS and Atlantic TC region; 55km over eastern Pacific to better capture ARs		elem distortion: 3.35 area based dx: min=23 km max=113 km	TBD	@Paul Ullrich
arcticx4v1pg2	atm/land: 25 km (ne120)	atm/land: 100 km (ne30)			elem distortion: 4.26 area based dx: min=23 km max=125 km	TBD	@Ben Hillman

Storm-Resolving Grids

Grid Name	Target Fine Resolution	Target Coarse Resolution	Goals in mesh creation	Link to mesh graphic	grid quality metric	Validation	Contact Person

Grid Name	Target Fine Resolution	Target Coarse Resolution	Goals in mesh creation	grid quality metric	Validation	Contact Person
CONUS ref(100W,40N) CONUS_ne32x4_lon100W_lat40N.g CONUS_ne32x8_lon100W_lat40N.g CONUS_ne32x16_lon100W_lat40N.g CONUS_ne32x32_lon100W_lat40N.g (no on E3SM inputdata server)	28 km (ne128), 14 km (ne256), 7km (ne512), 3.5 km (ne1024)	111km (ne32), 28 km (ne128)	Refinement region with complete coverage of CONUS using several coarse and fine resolutions	Max Dinv elem distortion: 3.00, 3.00, 3.01, 3.02 area based dx: min=24, 12, 6, 3 km max=105, 106,106,106 km	TBD	@Paul Ullrich
2012 North American Derecho derecho_ne512.g derecho_ne1024.g derecho_ne2048.g (not on E3SM inputdata server)	7 km (ne512), 3.5 km (ne1024), 1.75 km (ne2048)	100 km (ne32)	Include the region important for the 2012 North American Derecho	Max Dinv elem distortion: 2.89, 2.89, 2.97 area based dx: min=6.4, 3.2, 1.6 km max=28, 28, 28 km	Liu et al. (2023; under review)	@Paul Ullrich
California CA_ne32_x32_v1.g CA_ne32_x32_v2.g CA_ne32_x32_v3.g CA_ne32_x64_v1.g CA_ne32_x128_v1.g (not on E3SM inputdata server)	3.25 km (ne1024)	100 km (ne32)	High resolution over CA to capture topographic effects of precipitation, but small enough HR domain so that climate length simulations can be performed. Note that other experimental variants of this grid exist (contact @Peter Bogenschutz for details).	Max Dinv-based element distortion: 3.02, 3.02, 5.45, 3.04, 3.05 area based dx: min=3.3, 3.2, 2.4, 1.6, 0.8 km max=113, 113, 113, 113, 113 km	Zhang et al. (2023; in prep); Bogenschutz et al. (2023; in prep) Tang et al. (2023; in prep)	@Peter Bogenschutz@Qi Tang Jishi Zhang (zhang73@llnl.gov)
Amazon ref(60W,5S) (not on E3SM inputdata server)	14 km (ne256), 7 km (ne512), 3.5 km (ne1024)	28 km (ne128)	Large high resolution region over Amazon		TBD	@Paul Ullrich
ARM GoAmazon GoAmazon_ne32_x32_v1.g (not on E3SM inputdata server)	3.25 km (ne1024)	100 km (ne32)	For ARM GoAmazon field campaign	Max Dinv-based element distortion: 2.88 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma @Yunyan Zhang
ARM TRACER	3.25 km (ne1024)	100 km (ne32)	For ARM TRACER field campaign	Max Dinv-based element distortion: 3.06 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma @Yunyan Zhang
ARM COMBLE	3.25 km (ne1024)	100 km (ne32)	For ARM COMBLE field campaign	Max Dinv-based element distortion: 2.98 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma @Yunyan Zhang
ARM CACTI	3.25 km (ne1024)	100 km (ne32)	For ARM CACTI field campaign	Max Dinv-based element distortion: 2.98 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma @Yunyan Zhang
ARM MAGIC	3.25 km (ne1024)	100 km (ne32)	For ARM MAGIC field campaign	Max Dinv-based element distortion: 3.05 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma @Yunyan Zhang
ARM EPCAPE	3.25 km (ne1024)	100 km (ne32)	For ARM EPCAPE field campaign	Max Dinv-based element distortion: 2.88 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma @Yunyan Zhang
ARM CONUS	3.25km (ne1024)	100 km (ne32)	For SGP, SEUS, TRACER	Max Dinv-based element distortion: 2.98 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma @Yunyan Zhang
Indian Ocean, Maritime Continent	3.25km (ne1024)	100 km (ne32)	For MJO study	Max Dinv-based element distortion: 3.40 area based dx: min=3.2 km max=109 km	TBD	@Hsi-Yen Ma