= Name and subject of the action

Last edition: '''[[Wikinfo(changed_ts)]]''' by '''[[Wikinfo(changed_by)]]'''

The PI is responsible to closely follow the progress of the action, 
and especially to contact NEMO project manager if 
the delay on preview (or review) are longer than the 2 weeks expected.

[[PageOutline(2, , inline)]]

== Summary

||=Action       || AGRIF-03_jchanut_vert_coord_interp                    ||
||=PI(S)        || Jérôme Chanut and James Harle                         ||
||=Digest       || Online vertical interpolation with AGRIF (2019 cont.) ||
||=Dependencies || Nesting tools update, i.e. #2129 + new step flowchart ||
||=Branch       || source:/NEMO/branches/{YEAR}/dev_r{REV}_{ACTION_NAME} ||
||=Previewer(s) || S. Masson                                             ||
||=Reviewer(s)  ||                                                       ||
||=Ticket       || #2222                                                 ||

=== Description

{{{
This is a continuation from the IMMERSE task started in 2019. Changes to allow for vertical interpolation 
in NEMO have been implemented in December 2019 in the trunk. This task will eventually provide additional 
corrections and an update of the Nesting Tools. Since the idea is to use the DOMAINcfg tool for AGRIF, 
the task tackled in AGRIF-05_rblod_CMEMS (#2129) should ideally be completed first. 
}}}

''...''

=== Implementation

{{{#!box width=35em help
Describe flow chart of the changes in the code. \\
List the Fortran modules and subroutines to be created/edited/deleted. \\
Detailed list of new variables to be defined (including namelists), \\
give for each the chosen name and description wrt coding rules.
}}}

''...''

=== Documentation updates

{{{#!box width=55em help
Using previous parts, define the main changes to be done in the NEMO literature 
(manuals, guide, web pages, …).
}}}

''...''

== Preview 

{{{#!box width=50em info
[[Include(wiki:Developers/DevProcess#preview_)]]
}}}

''...''

== Tests





===  VORTEX test case
- Functionality: Detect nesting errors. Evaluate new algorithms. Check volume/tracer conservation with 2 way nesting.
- Setup: Self advected vortex over a beta plan. No forcing, flat bottom. Analytical definition of geostrophically balanced vortex.
- Verification value: No analytical solution of the solution exists. The parent domain at high resolution is usually used to have a quantitative measure of the nesting errors. 
One can nevertheless implement the following unit tests:
    Global volume should be conserved at machine accuracy

    Perfect symmetry of the results if switching hemisphere or reversing earth rotation

    1:1 nesting (i.e. no refinement in the zoom) and fully explicit time stepping mode should not change the results

- Status: available as part of NEMO test cases suite on svn.

=== 2DV OVERFLOW test case
- Functionality: Detect nesting errors with 1d varying topography. Evaluate vertical grid change within AGRIF zooms.
- Setup: based on existing OVERFLOW test case with an AGRIF zoom over the slope. Since offline bathymetry connection is important here, input domain file have to be provided. That's the main difference with existing test case.
- Verification value: No analytical solution of the solution exists. The parent domain at high resolution can be used to have a quantitative measure of the nesting errors. This test can be used to easily detect errors in the vertical coordinate change algorithm if vertical grids are actually identical.
- Status: Test case already set up but not transferred on any repository yet.

=== BOWL OVERFLOW test case (TBC)
- Functionality: Detect nesting errors with 2d varying topography. Evaluate vertical grid change within AGRIF zooms.
- Setup: Similar to the 2d OVERFLOW test case above but with 2d varying topography.
- Verification value: No analytical solution of the solution exists. The parent domain at high resolution can be used to have a quantitative measure of the nesting errors. 
- Status: Not available yet.

=== 2DV UPWELLING test case (TBC)
- Functionality: Detect nesting errors with 1d varying topography. Evaluate vertical grid change within AGRIF zooms and potential artefacts in the connection of surface/bottom boundary layers.
- Setup: issued form COMODO test cases, that's a stationary solution of a wind forced shelf overflow.
- Verification value: Analytical solution.
- Status: Not available yet.

=== DOME test case (TBC)
- Functionality: That's the classical experiment used in the literature to evaluate the numerical impact on dense overflows. It illustrates here the potential benefit of using a local vertical coordinate change and/or horizontal refinement on a longer time scale.
- Setup: Forced dense water flow in a channel over a linear slope (hence need bdy forcing). 
- Verification value: No analytical solution of the solution exists. The parent domain at high resolution can be used to have a quantitative measure of the nesting errors. 
- Status: Not available yet.

''...''

== Review

{{{#!box width=50em info
[[Include(wiki:Developers/DevProcess#review)]]
}}}

''...''