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- Edit or modify homme/test/jw_baroclinic/run.job for your system
- This script will configure, build and run the baroclinic problem for a variety of uniform resolutions.
- Use this script to generate a working namelist. Edit the namelist for newmesh.g:
- nu = 8.0e-8, nu_div = 8.0e-8, nu_p = 8.0e-8
- hypervis_scaling=3.2
- nu = 1e15, nu_div = 1e15, nu_p = 1e15
- fine_ne=30
- hypervis_power=3.322
- max_hypervis_courant = 1.9
- tstep_type=5, qsplit=1, rsplit=3, hypervis_subcycle=4
- ne=0
- mesh_file = “/user/path/to/newmesh.g”
- Use tensor hyperviscosity. Enabled with a non-zero value of hypervis_scaling. Settings are grid independent.
- OR: use the older scalar hypervisosity. Enabled with a non-zero value hypervis_power. Settings are grid independent. Warning: set only one of hypervis_scaling or hypervis_power.
- In idealized test cases (Guba et al., GMD, 2014) the tensor formulation shows less sensitivity to grid quality and less noise in the mesh transition region. However, in realistic simulations the differences between tensor and scalar hyperviscosity are less noticeable.
- use new, simplified dycore settings:
- Also change the value of ‘tstep’ to a value known to work with the finest resolution in newmesh.g
- Decrease tstep until run is stable
- HOMME will interpolate the results (u,v,T, vorticity and divergence, and tracers) and output on a NETCDF lat/lon grid and can be examined with NCL or ncview
Mesh Quality
- After reading in an RRM mesh, HOMME running in E3SM or standalone will compute various statistics including a measure of the mesh quality/distortion, output as “Max Dinv-based element distortion”. The equal-angle cubed-sphere grid has a value of 1.7. A high quality regionally refined grid will have a value less than 4. Getting a value less than 4 should be possible with a carefully defined refinement region and the SQuadGen ‘lowcon’ refinement option.