The internal_wave test group (compass.ocean.tests.internal_wave.InternalWave) implements variants of the internal wave test case. Here, we describe the shared framework for this test group and the 3 test cases.


The shared config options for the internal_wave test group are described in internal_wave in the User’s Guide.

Additionally, the test group has a shared namelist.forward file with a few common namelist options related to run duration and default horizontal and vertical momentum and tracer diffusion, as well as a shared streams.forward file that defines mesh, input, restart, and output streams.


The class compass.ocean.tests.internal_wave.initial_state.InitialState defines a step for setting up the initial state for each test case.

First, a mesh appropriate for the resolution is generated using mpas_tools.planar_hex.make_planar_hex_mesh(). Then, the mesh is culled to remove periodicity in the y direction. A vertical grid is generated, with 20 layers of 25-m thickness each by default. Finally, the initial temperature field is computed along with uniform salinity and zero initial velocity.


The class compass.ocean.tests.internal_wave.forward.Forward defines a step for running MPAS-Ocean from the initial condition produced in the initial_state step. If nu is provided as an argument to the constructor, the associate namelist option (config_mom_del2) will be given this value. If vlr is true, config_vertical_advection_method will be assigned "remap" rather than the default value of "flux-form". Namelist and streams files are generate during setup() and MPAS-Ocean is run (including updating PIO namelist options and generating a graph partition) in run().


The compass.ocean.tests.internal_wave.default.Default test performs a 15-minute run on 4 cores. It doesn’t contain any Validation.

There is also a variant for testing vertical Lagrangian remap capabilities at ocean/internal_wave/vlr/default.


The compass.ocean.tests.internal_wave.rpe_test.RpeTest performs a longer (20 day) integration of the model forward in time at 5 different values of the viscosity. These nu values are later added as arguments to the Forward steps’ constructors when they are added to the test case:

step = Forward(
    test_case=self, name=name, subdir=name, ntasks=4,
    openmp_threads=1, nu=float(nu))

The analysis step defined by compass.ocean.tests.internal_wave.rpe_test.analysis.Analysis makes plots of the final results with each value of the viscosity.

This test is resource intensive enough that it is not used in regression testing.

There is also a variant for testing vertical Lagrangian remap capabilities at ocean/internal_wave/vlr/rpe_test.


The compass.ocean.tests.internal_wave.ten_day_test.TenDayTest performs a longer (10 day) integration of the model forward in time.