Changes between Initial Version and Version 1 of ticket/0680_latphys

Timestamp:

2010-06-10T17:08:38+02:00 (14 years ago)

Author:

acc

Comment:

--

ticket/0680_latphys

@@ +1 @@
+[[PageOutline]]
+Last edited [[Timestamp]]
+
+[[BR]]
+
+'''Author''' : acc (on behalf of agn) 
+
+'''ticket''' : #680
+
+'''Branch''' : [https://forge.ipsl.jussieu.fr/nemo/browser/branches/DEV_r1924_nocs_latphys      DEV_r1924_nocs_latphys] 
+----
+
+=== Description ===
+This branch will contain the latest version of
+Griffies's implementation of the Gent and McWilliams eddy transport as a skew flux. This has the advantage that its numerical discretization can be written in terms of contributions from quarter cells – ‘triads’. This gives a tighter stencil, disallowing 2-gridpoint numerical noise that is permitted by the advective discretization.
+A working prototype code for the iso-neutral and skew-flux operator was carefully reviewed in 2009. Considerable care has been taken in the formulation to ensure the tensorial representation is consistent with the variable volume layers (s-coordinate/z* representation). This has been documented and will be provided with the release.[[BR]]
+
+
+'''Method'''[[BR]]
+
+ (1) Discretise Isopycnal diffusion in terms of these triads. This will obviate the need to smooth isopycnal slopes horizontally with a Shapiro filter (as currently implemented in NEMO), or to apply a background horizontal diffusivity that mixes diapycnally.[[BR]]
+
+ (2) Implement Visbeck et al.'s formulation of spatially varying diffusivities as an alternative to the current formulation based on the Held and Larichev timescale and the Rossby radius as a lengthscale (done).[[BR]]
+
+ (3) Add a slope limiting algorithm (mixed-layer depth is sensitive to the slope limiting that is employed) that behaves satisfactorily within and immediately below the mixed layer.[[BR]]
+
+ (4) Implementation in the trunk+ NVTK + documentation[[BR]]
+
+
+----
+=== 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..........