[[PageOutline]] Last edited [[Timestamp]] '''Author''' : Gurvan Madec, Florian Lemarié, George Nurser '''ticket''' : #1260 '''Branch''' : [https://forge.ipsl.jussieu.fr/nemo/browser/branches/2014/dev_CNRS0_NOC1_LDF 2014/dev_CNRS0_NOC1_LDF] '''WP2014 Action''' : [https://forge.ipsl.jussieu.fr/nemo/wiki/2014WP/2014Action_institutions_CNRS CNRS-0] & [https://https://forge.ipsl.jussieu.fr/nemo/wiki/2014WP/NOC NOC-1] ---- === Description === simplify and improve the lateral diffusion and dissipation in NEMO/OPA  Simplification: [[BR]]change the way the eddy diffusivity and viscosity are specified and controlled by the user. Improvements: [[BR]] (1) introduce Beckers et al. (2000) compact stencil in the cross-isoneutral direction in triads formalism ; [[BR]] (2) introduce in both iso-neutral operator the Method of Stabilizing Correction (Lemarié et al. (2012) ; [[BR]] (3) implement bilaplacian iso-neutral operator (Lemarié et al. (2012) ---- === Changes === '''revision [https://forge.ipsl.jussieu.fr/nemo/log/branches/2014/dev_CNRS0_NOC1_LDF?rev=4615 4615] ''' contains the following changes (validated with GYRE only): - all targeted improvements on OPA, i.e. (1) to (3) - simplification: (a) LDF entirely re-design. This includes numerous changes: new namelist ; bilaplacian operator written as re-entrant laplacian and bilaplacian eddy coefficient defined as sqrt(bhm) at u and v-points ; rotb and rotn arrays suppressed (even from the restart file) ; hdivn and hdivb removed from restart too ; divcur.F90 becomes divhor and only computes the horizontal divergence ; rename traldf_iso_grif.F90 into traldf_iso_triad.F90 ; redesign the management of eddy induced velocity and its associated diagnostics ; suppress CPP keys associated with slopes and eiv... '''revision [https://forge.ipsl.jussieu.fr/nemo/log/branches/2014/dev_CNRS0_NOC1_LDF?rev=4616 4616]''' contains the following changes (validated with GYRE only): - improvements : correct the omission of traldf_iso_triad.F90 in OPA_SRC/TRA - simplification 1 : introduce e1e2t,u,v and f , r1_e1e2t,u,v and f , r1_e1t,u,v and f, and r1_e2t,u,v and f and use them in all the codes - simplification 2 : remove key_vectopt_loop from all the code except in domzgr_substitute.h90 (it is an obsolescent feature only adapted to vector computers) - simplification 3 : remove all "!CDIR " lines = NEC vector compiler instructions '''revision [https://forge.ipsl.jussieu.fr/nemo/log/branches/2014/dev_CNRS0_NOC1_LDF?rev=4617 4617]''' contains the following changes (validated with GYRE_PISCES only): - all targeted improvements on TOP - simplifications of revision 4616 performed also on tracers '''remaining to do :''' - management of no-slip boundary condition as fmask no more used in dynvor.F90 .... - suppress Smagorinsky option which does not work any more. Can be re-introduce in a consistent way with the re-design LDF if decided... - test with SETE (especially restartability and reproducibility ) ---- === Testing === 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 [[BR]]New code doesn't change results when it is switched off [[BR]]and !''works!'' when switched on || !'''YES/NO/NA!''' || (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? [[BR]]!,,!''Preserving answers in model runs does not necessarily imply preserved diagnostics. !'' || !'''YES/NO!''' || 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....... ---- === Resources === !''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 * Ensure the code routine header is in accordance with the agreement, (Copyright/Redistribution etc).Add further details here if required..........