The landice/thwaites test group runs tests with a coarse (4-14-km) Thwaites Glacier mesh. The purpose of this test group is to provide a realistic glacier that includess an ice shelf. The mesh and initial condition are already generated. In the future, additional test cases may be added for generating a new version of the Thwaites mesh at different resolutions and using different data sources.


FO velocity solution visualized in Paraview. Grounding line position shown with a white line.

The test group includes three test cases, two of which have one or more steps that are variants on run_model (given other names in the decomposition and restart test cases to distinguish multiple model runs), which performs time integration of the model. There is a not an explicit smoke test, but the full_run step of the restart_test can be used as a smoke test.

The decomposition_test and restart_test test cases in this test group can only be run with the FO velocity solvers. Running with the FO solver requires a build of MALI that includes Albany. There is no integration step for the test case mesh_gen.

config options

The mesh_gen test case uses the default config options below. The other test cases do not use config options.


# number of levels in the mesh
levels = 10

# distance from ice margin to cull (km).
# Set to a value <= 0 if you do not want
# to cull based on distance from margin.
cull_distance = 10.0

# mesh density parameters
# minimum cell spacing (meters)
min_spac = 1.e3
# maximum cell spacing (meters)
max_spac = 8.e3
# log10 of max speed for cell spacing
high_log_speed = 2.5
# log10 of min speed for cell spacing
low_log_speed = 0.75
# distance at which cell spacing = max_spac
high_dist = 1.e5
# distance within which cell spacing = min_spac
low_dist = 5.e4

# mesh density functions
use_speed = True
use_dist_to_grounding_line = True
use_dist_to_edge = True


landice/thwaites/decomposition_test runs short (2-day) integrations of the model forward in time on 16 (16proc_run step) and then on 32 cores (32proc_run step) to make sure the resulting prognostic variables are bit-for-bit identical between the two runs.


landice/thwaites/restart_test first runs a short (5-day) integration of the model forward in time (full_run step). Then, a second step (restart_run) performs two subsequent 2 and 3 day integrations, where the second begins from a restart file saved by the first. Prognostic variables are compared between the “full” and “restart” runs to make sure they are bit-for-bit identical.


landice/thwaites/mesh_gen creates a variable resolution mesh based on the the config options listed above. This will not be the same as the pre-generated 4-14km mesh used in decomposition_test and restart_test because it uses a newer version of Jigsaw. Note that the basal friction optimization is performed separately and is not part of this test case.