ROBUST-01(2015WP)/MERCATOR-6 online coarsening

[cbricaud]

https://forge.ipsl.jussieu.fr/nemo/browser/branches/2015/dev_r5003_MERCATOR6_CRS

[cbricaud]

https://forge.ipsl.jussieu.fr/nemo/changeset/5007

in crs_dom_def: jpj_crs can be increased. all arrays with jpj_crs as dimension should be allocated affter. so crs_dom_alloc is splitted and crs_dom_alloc1 is called after dimension computing

in crs_dom_def: noso is refering to the proc on which where are computing, but it used in the loop on processors jn.
so we define iprocso which refers to proc jn.

in crs_dom_def: we change the loops on jn which are not compatible with mpp_ini2.
results are reproductible for 24.20.480 with the old loop and the new loop.
results are reproductible with the new loop for 24.20.480 and 24.20.390 .

crsini.F90: avoid divsion per 0. for facsurfu/v.

crsfld.F90: avoid division pr 0. with crs_volt_wgt for hdivn_crs

mppini.F90 and mppini_2.h90: modifications to allow landprocessor removing with CRS.

[cbricaud]

https://forge.ipsl.jussieu.fr/nemo/changeset/5010

bug detected:
in crsfld: crs_volt_wgt,crs_surfu_wgt and crs_surfv_wgt are used to compute hdiv.
but they are declared/allocated, but no computed. do hdiv=0 in coarsened ouputs.
change computing of hdivn_crs(ji,jj,jk)

allow CRS to run with ln_nogather=T

[cbricaud]

changes at rev5601:
https://forge.ipsl.jussieu.fr/nemo/changeset/5601

running with ORCA025_LIM2, time-splitting, fixed volume and age tracer

[cbricaud]

merge change from trunk rev 5003 to 5519 ( rev where branche 3.6_stable were created ):
svn merge -r 5003:5519 ​svn+ssh://cbricaud@forge.ipsl.jussieu.fr/ipsl/forge/projets/nemo/svn/trunk .
commit at rev 5602.
​https://forge.ipsl.jussieu.fr/nemo/changeset/5602

[cbricaud]

the branch containing the online coarsening of BCG model is available here:
https://forge.ipsl.jussieu.fr/nemo/browser/branches/2015/dev_r5003_MERCATOR6_CRS

This branch is associated nemo 3.6 stable ( available here: https://forge.ipsl.jussieu.fr/nemo/browser/branches/2015/nemo_v3_6_STABLE/NEMOGCM )
This branch is phased with rev 7213 of nemo 3.6 stable.

Coarsening capacity can be used:

• for output of physics variables at a lower resolution
• or to run a configuration using TOP online at a lower resolution

A "readme" is available in the branch : NEMOGCM/CRS_help/README_COARSENING.txt

At the moment, coarsening can not be activated with PISCES; it will be available in the next weeks.

Different runs have been performed with Age tracer to validate coarsening implementation:

• a run 'full resolution' based on eORCA025_LIM3 ( physic and passive tracer at 1/4° resolution )
• a run 'low resolution' based on eORCA075_LIM3 ( physic and passive tracer at 3/4° resolution )
• a run with coarsening based on eORCA025_LIM3 ( physic at 1/4° resolution and passive tracer at 3/4° resolution )

Age tracer from the coarsened run well reproduce age tracer from 'full resolution' run.

[cbricaud]

At the revision 7345 of this branch is, PISCES routines has not been impacted.

[cbricaud]

commit a first implementation of coarsening in PISCES at rev7398 ( https://forge.ipsl.jussieu.fr/nemo/changeset/7398 )
PISCES is running with coarsening ( not crash ) but there is a problem of CHL productions. problem under investigation
Note that, as TOP need to read data from files for tracers CI , or as PISCES needs too to read data from files , there is a change in IOM to tell it when reading is done in 'coarsened space'

[cbricaud]

​http://forge.ipsl.jussieu.fr/nemo/changeset/7520 : now PISCES is running with online coarsening
​http://forge.ipsl.jussieu.fr/nemo/changeset/7521 : big correction for mother grid domain definition in coarsening

[cbricaud]

Different bugfix have been committed :
see ​http://forge.ipsl.jussieu.fr/nemo/changeset?reponame=&new=8103%40branches%2F2015%2Fdev_r5003_MERCATOR6_CRS&old=7806%40branches%2F2015%2Fdev_r5003_MERCATOR6_CRS

• 2 bug fixes on lateral diffusion
• maskland option ok for coarsening variables
• horizontal surfaces changed fot isopycnal diffusion and surface fluxes coarsening
• bugfixes on coarsned grid local indices computing
• restartabity ok

[nemo]

Remove 'Development' type

[nemo]

Batch modification of milestone field set to 'Unscheduled'

[nicolasmartin]

Now the CRS branch is located source:/NEMO/branches/2018/dev_r5003_MERCATOR6_CRS

Should consider an last one phase with 3.6 release at some point.