overflow

The overflow task group is currently comprised of one default task for quick testing, particularly against a baseline, and one rpe test which shows how the resting potential energy changes across forward runs with different viscosities.

framework

The shared config options for overflow tests are described in overflow in the User’s Guide.

Additionally, the tests share a forward.yaml file with a few common model config options related to time management, time integration, and Laplacian viscosity, as well as defining mesh, input, restart, and output streams.

init

The class polaris.tasks.ocean.overflow.init.Init 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 x and y directions. The bottom topography is defined along with a vertical grid with 60 layers by default. Next, the ocean state is generated with cold water on the continental shelf.

forward

The class polaris.tasks.ocean.overflow.forward.Forward defines a step for running the ocean from the initial condition produced in the init step. Namelist and streams files are updated in polaris.tasks.ocean.overflow.forward.Forward.dynamic_model_config() with time steps determined algorithmically based on config options. The number of cells is approximated from config options in polaris.tasks.ocean.overflow.forward.Forward.compute_cell_count() so that this can be used to constrain the number of MPI tasks that Polaris tasks have as their target and minimum (if the resources are not explicitly prescribed). For MPAS-Ocean, PIO namelist options are modified and a graph partition is generated as part of runtime_setup(). Next, the ocean model is run. The duration is set by run_duration in the config section corresponding to the task (overflow_default or overflow_rpe). Finally, validation of layerThickness, temperature and normalVelocity in the output.nc file are performed against a baseline if one is provided when calling polaris setup.

viz

The polaris.tasks.ocean.overflow.viz.Viz plots the initial and final temperature along a transect perpendicular to the continental slope.

default

The polaris.tasks.ocean.overflow.default.Default test runs the init step, a short forward step, and the viz step.

rpe

The polaris.tasks.ocean.overflow.rpe.Rpe test performs the init step, 5 forward steps corresponding to the viscosity values in the config file, and the analysis step.

analysis

The polaris.tasks.ocean.overflow.rpe.analysis.Analysis computes the Resting Potential Energy (RPE). This step also produces a figure with RPE time evolution for each forward run and a figure with each of the forward run’s transects at the plot_time designated in the config file.