Version 13 (modified by clevy, 20 months ago) (diff)

Name and subject of the action

Last edition: 11/27/20 17:20:13 by emalod

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.

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


Action OASIS_TESTCASE : create a test case for coupling with OASIS
PI(S) Claire Lévy
Digest Motivations and main tasks: create a simple testcase using OASIS to help building new coupled configurations
Dependencies OASIS
Branch source:NEMO/branches/2020/dev_r12565_VALID-11_clevy_OASIS_TESTCASE
Previewer(s) E. Maisonnave & Laure Coquart
Reviewer(s) E. Maisonnave & Laure Coquart
Ticket #2379


Create a simple testcase using OASIS to help building new coupled configurations.
Will use OASIS and a simplified fake atmosphere (TOY_ATM in OASIS wording.
May do more than only ocean-atmosphere coupling (to be discussed).
Useful as coupling demonstrator and for first level valisation of coupling with OASIS in future NEMO versions.


As for the test case defined in STEP1 (see below):

  • no changes in NEMO code
  • Changes in &namsbc_cpl namelist
  • Need to add the TOY_ATM software, as a simplified /fake atmosphere somewhere to be able tu run this test case

Documentation updates

Updates needed:



STEP 1: Implement in the up-to-date version for 2020 the test case developed in 2018

Restarting from /ccc/work/cont003/gen7451/clevy/VALID_CPL_4.0/trunk/cfgs/CPL_TOYATM in irene computer, implement the CPL_OASIS in the up-to-date NEMO version, as a test case (in "dev_branch"/tests).

CPL_OASIS test case description:

  • Based on the ORCA2_ICE_PISCES reference configuration, activate coupling to a TOYATM (kindly offered by Eric M.) through OASIS
  • coupled fields (from &namsbc_cpl namelist in namelist_cfg file)
  • runing 10days, coupling every time step (nn_fsbc=1)
  • The test cases needs OASIS and a simple TOYATM
  • Where should the TOYATM be installed? In the test case, in NEMO tools? elsewhere?
  • Validation of the test case remains to be defined more precisely (check OASIS output compared to ocean SST ?)

STEP 2: is this the final version of the expected test case?

  • Adding other couplings?
  • Checking sea-ice?

STEP 3: implement final test case

Implement the finalised test case as part of the usual validation testbed, and also in the github for NEMO test cases

Answer from reviewers is in the ticket #2379. For E. Maisonnave & L. Coquart, review is successful and development can start


This toy is able to validate a simplified OASIS based coupled configuration of NEMO in such a way that:

  • the OASIS library can be compiled on the targeted machine (OASIS libraries available in the OASIS directory)
  • the OASIS library can be linked with a coupled configuration of NEMO (the NEMO executable is available in the NEMO cfg directory) and an atmosphere toy model (executable available in the tools/TOYATM directory)
  • an MPI MPMD system (two executables at the same time) can be launched on the machine and a successful simulation can be achieved if :
  • a run.stat file is produced and includes 160 iterations:
nemo_iterations=wc -l run.stat | awk {'print $1'} | grep 160; [ -n "$nemo_iteration" ] && echo true
echo false
  • OASIS indicates a successful end of the run:
success=grep "SUCCESSFUL RUN" debug.root.0? | wc -l | grep 2; [ -n "$success" ] && echo true
echo false
  • the sea surface temperature (Tropical Pacific region) as seen by the toy atmosphere model is close to 300.20 K and the difference between the end and the beginning values doesn't exceed 0.5 K

This can be checked e.g. in the check file produced by the commands: ncks -h -v ATSSTSST -d nx,80,120 -d ny,0,10 ; ncwa -h -a nx,ny


IMPORTANT: for now, I've not been able to commit in the development branch the change for external tools (in order to point on the new branch TEMPORARY BYPASS:

  • Download the development branch
    svn co

The tools subdirectory is now extracted for this branch from the new development branch created to update TOYATM: tools_CPL_OASIS_ticket2379_2020

More details on how to set up and run the CPL_OASIS test case in ./tests/CPL_OASIS/


Once the development is done, the PI should complete the tests section below and after ask the reviewers to start their review.

This part should contain the detailed results of SETTE tests (restartability and reproducibility for each of the reference configuration) and detailed results of restartability and reproducibility when the option is activated on specified configurations used for this test

Regular checks:

  • Can this change be shown to produce expected impact (option activated)?
  • Can this change be shown to have a null impact (option not activated)?
  • Results of the required bit comparability tests been run: are there no differences when activating the development?
  • If some differences appear, is reason for the change valid/understood?
  • If some differences appear, is the impact as expected on model configurations?
  • Is this change expected to preserve all diagnostics?
  • If no, is reason for the change valid/understood?
  • Are there significant changes in run time/memory?


A successful review is needed to schedule the merge of this development into the future NEMO release during next Merge Party (usually in November).


  • Is the proposed methodology now implemented?
  • Are the code changes in agreement with the flowchart defined at preview step?
  • Are the code changes in agreement with list of routines and variables as proposed at preview step?
    If, not, are the discrepancies acceptable?
  • Is the in-line documentation accurate and sufficient?
  • Do the code changes comply with NEMO coding standards?
  • Is the development documented with sufficient details for others to understand the impact of the change?
  • Is the project literature (manual, guide, web, …) now updated or completed following the proposed summary in preview section?


Is the review fully successful? If not, please indicate what is still missing

Once review is successful, the development must be scheduled for merge during next Merge Party Meeting.