Version 3 (modified by gm, 5 years ago) (diff)

Last edited Timestamp?

Author : Gurvan Madec, Florian Lemarié, George Nurser

ticket : #1593

Branch : 2015/dev_r5721_CNRS9_NOC3_LDF

WP2015 Action : CNRS-9 and NOC-3


Development branch related to CNRS-9 and NOC-3 actions of 2015 work plan :
• simplify and improve the tracer advection and the lateral diffusion and dissipation in NEMO/OPA
• generalization of the use of surface scale factors (e1e2 at T, U, V, F points)

NB: This development consists in merging the current trunk with the last year work on that subject (see ticket #1260, and the associated branch ​​2014/dev_CNRS0_NOC1_LDF​ and wiki page ​​1260_CNRS0_NOC1_LDF.

(1) define bi-laplacian diffusive operator on dynamics and tracers are re-entrant laplacian ;
(2) change the way the eddy diffusivity and viscosity are specified and controlled by the user ;
(3) generalize of the use of surface scale factors ;
(4) add a optional read of surface scale factors in coordinate file in case of reduction of the scale factors in some straits.

(1) introduce Beckers et al. (2000) compact stencil in the cross-isoneutral direction in triads formalism ;
(2) introduce in both iso-neutral operator the Method of Stabilizing Correction (Lemarié et al. (2012) ;
(3) implement bilaplacian iso-neutral operator (Lemarié et al. (2012).


Three steps:

  1. Phasing of scale factors

(I.0) standardisation of the name of quantities derived from horizontal scale factors (many modules of NEMO)
  inverse of scale factors : r1_e1t, r1_e2t, r1_e1u, r1_e2u, r1_e1v, r1_e2v, r1_e1f, r1_e2f
surfaces and their inverse:    e1e2t, e1e2u , e1e2v, e1e2f  and, r1_e1e2t , r1_e1e2u , r1_e1e2v, r1_e1e2f
ratio (used in traldf…) : e2_e1u , e1_e2v(I.1) generalize of the use of surface scale factors ;

(I.2) add a optional read of surface scale factors in coordinate file (domhgr.F90)
The input coordinate file have to include e1e2u and e1e2v in case of reduction of the scale factors in some straits.
When e1u or e2v are reduced in some straits, the surface at u- and v-points remains unchanged.
This allows to suppress the dom_vvl_orca_fix routine.

  1. Phasing of the advective/diffusive trends on tracers

(II.0) …

  1. Phasing of viscous trends




Testing could consider (where appropriate) other configurations in addition to NVTK].

NVTK Tested '''YES/NO'''
Other model configurations '''YES/NO'''
Processor configurations tested [ Enter processor configs tested here ]
If adding new functionality please confirm that the
New code doesn't change results when it is switched off
and ''works'' when switched on

(Answering UNSURE is likely to generate further questions from reviewers.)

'Please add further summary details here'

  • Processor configurations tested
  • etc——

Bit Comparability

Does this change preserve answers in your tested standard configurations (to the last bit) ? '''YES/NO '''
Does this change bit compare across various processor configurations. (1xM, Nx1 and MxN are recommended) '''YES/NO'''
Is this change expected to preserve answers in all possible model configurations? '''YES/NO'''
Is this change expected to preserve all diagnostics?
,,''Preserving answers in model runs does not necessarily imply preserved diagnostics. ''

If you answered '''NO''' to any of the above, please provide further details:

  • Which routine(s) are causing the difference?
  • Why the changes are not protected by a logical switch or new section-version
  • What is needed to achieve regression with the previous model release (e.g. a regression branch, hand-edits etc). If this is not possible, explain why not.
  • What do you expect to see occur in the test harness jobs?
  • Which diagnostics have you altered and why have they changed?Please add details here……..

System Changes

Does your change alter namelists? '''YES/NO '''
Does your change require a change in compiler options? '''YES/NO '''

If any of these apply, please document the changes required here…….


''Please ''summarize'' any changes in runtime or memory use caused by this change……''

IPR issues

Has the code been wholly (100%) produced by NEMO developers staff working exclusively on NEMO? '''YES/ NO '''

If No:

  • Identify the collaboration agreement details
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