slm_circ_icesheet

The slm_circ_icesheet test group (compass.landice.tests.slm_circ_icesheet.SlmCircIcesheet) adds a framework for evaluating coupled MALI and Sea-Level Model (SLM) behavior. The group contains two test cases:

  • mesh_convergence (compass.landice.tests.slm_circ_icesheet.circ_icesheet.CircIcesheetTest), which compares MALI-derived and SLM-derived estimates of sea-level change across a parameter sweep of mesh and SLM resolutions.

  • smoke_test, a minimal test case intended for quick validation and CI.

framework

The shared config options for this group are documented in slm_circ_icesheet in the User’s Guide.

The configure() method of CircIcesheetTest parses two comma-delimited parameter lists from the config:

  • mali_res from the [circ_icesheet] section, and

  • slm_nglv from the [slm] section.

The test case then creates one setup_mesh and one run_model step for each (mali_res, slm_nglv) pair. Step names follow the pattern mali<res>km_slm<nglv>/<step>. A single visualize step is then added to summarize and compare all runs.

setup_mesh

The class compass.landice.tests.slm_circ_icesheet.circ_icesheet.setup_mesh.SetupMesh builds all inputs required by MALI and SLM coupling for each (mali_res, slm_nglv) combination:

  • creates a planar hex mesh and culls it,

  • converts the mesh to a MALI grid and writes graph.info,

  • applies idealized circular initial conditions,

  • writes an SMB forcing file (either radial or vertical forcing), and

  • builds MALI<->SLM mapping files with ESMF.

The mapping workflow creates an SLM SCRIP grid from slm_nglv and slm_res, creates a MALI SCRIP file from the generated MALI grid, and then builds both mapping_file_mali_to_slm.nc and mapping_file_slm_to_mali.nc.

run_model

The class compass.landice.tests.slm_circ_icesheet.circ_icesheet.run_model.RunModel consumes the mesh, graph, SMB forcing, and mapping files from setup_mesh and runs MALI with SLM coupling options enabled in namelist.landice.

During setup(), the step also:

  • creates OUTPUT_SLM and ICELOAD_SLM directories,

  • renders namelist.sealevel from the Jinja template compass.landice.tests.slm_circ_icesheet.namelist.sealevel.template, and

  • fills SLM input paths from the slm_input_root config option.

The expected structure beneath slm_input_root is:

  • icemodel/GL<nglv>/ice_noGrIS_GL<nglv>/

  • others/GL<nglv>/

  • earthmodel/

visualize

The class compass.landice.tests.slm_circ_icesheet.circ_icesheet.visualize.Visualize collects all output.nc files produced by the parameter sweep and computes diagnostic quantities for coupled MALI-SLM comparison.

For each run combination, the analysis computes grounded-ice mass change, sea-level contributions with and without the z0 term, and percent-error metrics relative to SLM outputs. The step can generate:

  • per-case time-series plots,

  • per-resolution error curves over slm_nglv, and

  • a heat map of mean percent error.

The [circ_icesheet_viz] section controls plot output (save/hide figures) and provides constant ocean-area values used as analysis fallbacks.