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2019WP/AGRIF-05_jchanut_vert_coord_interp – NEMO

Version 9 (modified by jchanut, 4 years ago) (diff)


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  1. Summary
  2. Development plan
  3. Preview
  4. Tests
  5. Review


Action AGRIF-05_jchanut_vert_coord_interp
PI(S) Jérôme Chanut, James Harle


Developments to nesting (IMMERSE T3.2: Lead Mercator-Ocean , Participants: NERC ) The two-way nesting AGRIF capability will be developed in year 1 to allow each inner nest to use a different vertical coordinate from the model in which it is nested.

Trac Ticket #2222
SVN branch NEMO/branches/2019/dev_r11233_AGRIF-05_jchanut_vert_coord_interp
Previewer(s) Rachid Benshila
Reviewer(s) TBD
Link ExtractUrl(.)?

Development plan

  1. Simplify existing AGRIF code (open boundary routines only - update part unchanged):
    • Remove any non purely local update near boundaries, e.g. 3 points velocity filtering near boundaries / upstream advection for tracers for outflows. Target is "specified" open boundaries (this does change the results).
    • Ensure that NEMO-AGRIF handles small (~3x3 points) local mpp sub-domains (the preceding task should enable that more easily - current status is local sub-domains greater than ~10x10 points, e.g. greater than sponge layer width).
  2. Check current interpolation of vertical nesting (key_vertical).
    • Ensure that with identical vertical grids, results are bit-for-bit identical (VORTEX).
    • Optimization ? Consider existing PPM interpolation at this stage.
  3. Volume connection with different coordinate systems.
    • Existing code supports only nesting a z-coord model into a z-coord model. Should be more general.
    • Nesting tools have to be updated to allow this. Grenoble's version of Nesting tools (available on NEMO trac) should be the starting point.
  4. Design test cases (beside VORTEX)
    • One should check how boundary layers react at the domains boundaries (top and bottom): extrapolation methods will matter here.
    • Overflow test case (3D). Internal Wave packet crossing the boundary. 2D upwelling. Others ?
  5. Implement other remapping methods.
    • Could be borrowed from D. Engwirda (MOM6) library.
    • Should be coordinated with Mike Bell who plans to use the package for pressure gradient scheme.
  6. Set up a realistic test case (Denmark strait +Med overflows in ORCA12) in col. with WP6 (TBD).
    • How far in the validation should we go ? Not sure this is really part of the WP3.


Error: Failed to load processor box
No macro or processor named 'box' found


Reproducibility tests (VORTEX, 60 cores, 100 parent steps - diff run.stat 1_run.stat):

revision: 11573

2 way mode (ln_agrif_2way = .true.)

jpni x jpnj jpimax x jpjmax (child) status
10 x 6 9 x 13 ref
5 x 12 15 x 8 ok
12 x 5 8 x 15 ok
15 x 4 7 x 18 ok
4 x 15 18 x 7 NOK
30 x 2 5 x 34 memory corruption !

1 way mode (ln_agrif_2way = .false.)

jpni x jpnj jpimax x jpjmax (child) status
10 x 6 9 x 13 ref
30 x 2 5 x 34 ok
1 x 60 65 x 4 ok
60 x 1 4 x 65 ok

1 way mode is reproducible down to subdomains lower or equal to 4. It means that changes made in #2199 and included in this revision do work as expected. There is still an issue with small mpp subdomains in the update stage that may come from the AGRIF library.