# sphere_transport¶

The `sphere_transport`

test group implements 4 test cases for standard
transport schemes. See sphere_transport in the User’s Guide for
more details.

## rotation_2d¶

The `compass.ocean.tests.sphere_transport.rotation_2d.Rotation2D`

test performs a series of 12-day runs that advect 3 tracers around the sphere
with solid-body rotation. The resolution of the sphere varies (by default,
between 60 and 240 km). Advected results are compared with a known exact
solution to determine the rate of convergence. See
rotation_2d for config options and
more details on the test case.

### mesh¶

The class `compass.ocean.tests.sphere_transport.rotation_2d.mesh.Mesh`

defines a step for building a global mesh with uniform resolution using
`mpas_tools.ocean.build_mesh.build_spherical_mesh()`

.

### init¶

The class `compass.ocean.tests.sphere_transport.rotation_2d.init.Init`

defines a step for setting up the initial state for each test case with a
tracer distributed in a cosine-bell shape.

### forward¶

The class `compass.ocean.tests.sphere_transport.rotation_2d.forward.Forward`

defines a step for running MPAS-Ocean from the initial condition produced in
the `initial_state`

step. The time step for a given resolution is given by
the `timestep_munutes`

config option. Other namelist options are taken from
the test case’s `namelist.forward`

.

### analysis¶

The class `compass.ocean.tests.sphere_transport.rotation_2d.analysis.Analysis`

defines a step for plotting various results of the simulations in
`rotation_2d_convergence.pdf`

and at each resolution in `*_sol.pdf`

.

## nondivergent_2d¶

The `compass.ocean.tests.sphere_transport.nondivergent_2d.Nondivergent2D`

test performs a series of 12-day runs that advect 3 tracers around the sphere
within a divergence-free flow. The resolution of the sphere varies (by default,
between 60 and 240 km). Advected results are compared with a known exact
solution to determine the rate of convergence. See
nondivergent_2d for config options and
more details on the test case.

### mesh¶

The class `compass.ocean.tests.sphere_transport.nondivergent_2d.mesh.Mesh`

defines a step for building a global mesh with uniform resolution using
`mpas_tools.ocean.build_mesh.build_spherical_mesh()`

.

### init¶

The class `compass.ocean.tests.sphere_transport.nondivergent_2d.init.Init`

defines a step for setting up the initial state for each test case with a
tracer distributed in a cosine-bell shape.

### forward¶

The class `compass.ocean.tests.sphere_transport.nondivergent_2d.forward.Forward`

defines a step for running MPAS-Ocean from the initial condition produced in
the `initial_state`

step. The time step for a given resolution is given by
the `timestep_munutes`

config option. Other namelist options are taken from
the test case’s `namelist.forward`

.

### analysis¶

The class `compass.ocean.tests.sphere_transport.nondivergent_2d.analysis.Analysis`

defines a step for plotting various results of the simulations in
`nondivergent2D_convergence.pdf`

and at each resolution in `*_sol.pdf`

.

## divergent_2d¶

The `compass.ocean.tests.sphere_transport.divergent_2d.Divergent2D`

test performs a series of 12-day runs that advect 3 tracers around the sphere
within a flow with nonzero divergence. The resolution of the sphere varies (by
default, between 60 and 240 km). Advected results are compared with a known
exact solution to determine the rate of convergence. See
divergent_2d for config options and
more details on the test case.

### mesh¶

The class `compass.ocean.tests.sphere_transport.divergent_2d.mesh.Mesh`

defines a step for building a global mesh with uniform resolution using
`mpas_tools.ocean.build_mesh.build_spherical_mesh()`

.

### init¶

The class `compass.ocean.tests.sphere_transport.divergent_2d.init.Init`

defines a step for setting up the initial state for each test case with a
tracer distributed in a cosine-bell shape.

### forward¶

The class `compass.ocean.tests.sphere_transport.divergent_2d.forward.Forward`

defines a step for running MPAS-Ocean from the initial condition produced in
the `initial_state`

step. The time step for a given resolution is given by
the `timestep_munutes`

config option. Other namelist options are taken from
the test case’s `namelist.forward`

.

### analysis¶

The class `compass.ocean.tests.sphere_transport.divergent_2d.analysis.Analysis`

defines a step for plotting various results of the simulations in
`divergent2D_convergence.pdf`

and at each resolution in `*_sol.pdf`

.