baroclinic_channel
The baroclinic channel tests in polaris.ocean.tasks.baroclinic_channel are
variants of the Baroclinic Eddies test case (see
baroclinic channel) at 3 resolutions (1, 4 and 10 km). Here,
we describe the 5 test cases and their shared framework.
framework
The shared config options for baroclinic_channel tests are described in
baroclinic channel in the User’s Guide.
Additionally, the tests share a forward.yaml file with a few common model
config options related to run duration and default horizontal and vertical
momentum and tracer diffusion, as well as defining mesh, input, restart,
and output streams.
init
The class polaris.ocean.tasks.baroclinic_channel.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 y direction. A vertical grid is generated,
with 20 layers of 50-m thickness each by default. Next, the initial
temperature field is computed along with uniform salinity and zero initial
velocity. Finally, if a baseline is available, the step ensures that of
temperature, salinity and layerThickness in the initial_state.nc file
identical to those same fields from the baseline run.
The same init step is shared by all tasks at a given resolution.
forward
The class polaris.ocean.tasks.baroclinic_channel.forward.Forward
defines a step for running MPAS-Ocean from the initial condition produced in
the init step. If nu is provided as an argument to the
constructor, the associate namelist option (config_mom_del2) will be given
this value. Namelist and streams files are updated in
polaris.ocean.tasks.baroclinic_channel.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.ocean.tasks.baroclinic_channel.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. Finally, validation of temperature, salinity,
layerThickness and normalVelocity in the output.nc file are performed
against a baseline if one is provided when calling polaris setup.
validate
The class polaris.ocean.tasks.baroclinic_channel.validate.Validate
defines a step for validating outputs in two step directories against one
another. This step ensures that temperature, salinity, layerThickness
and normalVelocity are identical in output.nc files in the two steps.
default
The polaris.ocean.tasks.baroclinic_channel.default.Default
test performs a 3-time-step run on 4 cores.
decomp
The polaris.ocean.tasks.baroclinic_channel.decomp.Decomp
performs a 15-minute run once on 4 cores and once on 8 cores. The
validate step ensures that the two runs produce identical results.
restart
The polaris.ocean.tasks.baroclinic_channel.restart.Restart
performs a 10-minute run once on 4 cores, saving restart files every time step
(every 5 minutes), then it performs a restart run starting at minute 5 for 5
more minutes. The validate step ensures that the two runs produce identical
results.
Restart files are saved at the task level in the restarts directory,
rather than within each step, since they will be used across both the full
and restart steps.
The full.yaml file is used to set up the run duration and restart frequency
of the full run, while restart.yaml makes sure that the restart step begins
with a restart at minute 5 and runs for 5 more minutes.
threads
The polaris.ocean.tasks.baroclinic_channel.threads.Threads
performs a 15-minute run once on 4 cores, each with 1 thread and once on 4
cores, each with 2 threads. The validate step ensures that the two runs
produce identical results.
Note
The ocean/baroclinic_channel/10km/thread/1thread step is identical
to ocean/baroclinic_channel/10km/default/forward. If
ocean/baroclinic_channel/10km/thread is included in a suite,
it would be redundant to include ocean/baroclinic_channel/10km/default in the
suite as well.
rpe
The polaris.ocean.tasks.baroclinic_channel.rpe.Rpe
performs a longer (20 day) integration of the model forward in time at 5
different values of the viscosity. Versions of the test case exist at each of
the 3 default horizontal resolutions (1, 4 and 10 km).
The analysis step defined by
polaris.ocean.tasks.baroclinic_channel.rpe.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.