Changes between Initial Version and Version 1 of WorkingGroups/AGRIF/01-30-2014-WGmeeting

Timestamp:

2017-04-07T15:06:31+02:00 (7 years ago)

Author:

jchanut

Comment:

--

WorkingGroups/AGRIF/01-30-2014-WGmeeting

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+== REPORT OF THE WORKING GROUP MEETING (January 30, 2014) == #REPORTOFTHEWORKINGGROUPMEETINGJanuary302014
+Participants : Rachid Benshila, Daley Calvert, Julien Calandreau, Jérome Chanut, Laurent Debreu, Christian Ethe, Rachel Furner, Claire Levy, Gurvan Madec, Sébastien Masson
+
+=== 1) Discuss the update of the 3.6 version === #a1Discusstheupdateofthe3.6version
+==== History : ====
+ * [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] version (and corresponding NEMO subroutines) has been updated by Julien Calandreau (INRIA) and Laurent Debreu
+
+ * Jérome Chanut has made a lot of improvements and bug fixes in his Gilbraltar Strait configuration
+
+ * Same for Sébastien Masson in the Pulsation ANR project
+
+ * Other developments in LIM, PISCES
+
+==== Bugs that have been identified and corrected since version 3.4 : ====
+ * zwork array (J. Chanut): a global array « zwork » was defined in the libmpp module and (due to a bug in the [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] converter) this led to several problems and in particular the update step was not performed …
+
+ * Diffusion coefficients in the corners of the sponge layern were wrong (J. Chanut)
+
+ * Scale factors were not correctly computed in the ghost cells (where it is assumed that we are in full steps) (J. Chanut)
+
+-> same problem for OBC
+
+ * TKE (S. Masson): near the boundaries, spatial averaging operations led to wrong Kz in the first cell inside the high resolution domain. Extrapolation is possible but does not fulfill the requirement that with, a mesh refinement factor of 1, the obtained solution of the HR grid is identical to a solution computed without a zoom. S. Masson has implemented exchanges of TKE between coarse and fine grids.
+
+-> Same problem for GLS and for OBC
+
+ * Asselin Filter (J. Chanut) : when updating the « after » (n+1) fields, the corresponding corrections of the « now » fields were not done.
+
+ * arrays out of bound in procnames in MPI (wrong declarations of [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] profiles in agrif_declare_variables: jpi, jpj have been replaced by ncli,nlcj)
+
+==== Bugs / Problems that have been identified ==== #BugsProblemsthathavebeenidentified
+· The bathymetry connection check is not complete (add a check that the coarse grid bathy have been correctly updated)
+
+· Reproducibility is not guaranteed (due to MPI problem) when ln_spc_dyn is set to true in namelist (which means that we take 0 as special value for dynamics in interpolations/updates).
+
+· Recursive updates. When more than 1 zoom level are set, the update should start from the highest resolution grid and go recursively to the root grid. Laurent implemented changes that makes this possible.
+
+ * Use of [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] for degradation online (problème de north pole, coarsening)
+
+ * Average operators with update values
+
+ * High order operators with coastlines
+
+ * BDY problem have been solved
+
+==== Improvements ==== #Improvements
+ * [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] and time splitting (OK for version 3.6, end of the year, Jérome)
+   * only consider forward integration of the forcing mode permits to ensure volume conservation
+   * without update of the parent grid right hand side
+ * Performance of parallel runs
+   * allows the distribution of the processors among the fine grids
+
+'''''Rachid Benshila''' is ready be in charge of the merge''
+
+=== 2) What are the known open problems ? (not to be solved for 3.6) === #a2Whataretheknownopenproblemsnottobesolvedfor3.6
+ * Number of ghost cells ('''''L. Debreu''''')
+   * Antartic problem (periodicity): require only one ghost cell instead of 2
+   * Number of required ghost cells for high order advection schemes may be larger than 2
+   * -> Remove hardcoding of the number of ghost cells, do the required modifications to the [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] “profiles” (Laurent)
+
+ * North fold problem
+
+ * Timings for each grid
+
+=== 3) What are the main next developments? === #a3Whatarethemainnextdevelopments
+ * Coupling between grids at the level of the barotropic mode (in time splitting version) (Jérome)
+   * requires some modification in the organization of the step routine of NEMO
+
+ * Vertical grid refinement (Laurent)
+ * Online coarsening for tracers using [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] (L. Debreu, G. Madec)
+ * [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] with variable volume
+
+=== 4) Nesting tools: ===
+Two stages:
+
+a) for 3.6 version
+
+ * agree on all the points: bathymetry smoothing, update of coarse grids (take the maximum as default)
+
+ * Incorporate corrections done by Jean Marc
+
+ * The nesting tools are only essential for the creation of bathymetry:
+   * forcings can be interpolated on the fly
+   * -> Do a list available tools for 3D interpolation (initialization / restart fields)
+   * For 3.6 keep the 3D fields interpolation in nesting tools
+
+b) next version
+
+ * The definition of vertical coordinates should be done outside NEMO
+
+ * Nesting tools for the s coordinates
+
+==== 5) Documentation: ====
+ * Update of the nesting tools 3.6 documentation
+
+ * Update of the users guide: describes what is possible or not with [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF].
+
+ * Documentation for nesting in NEMO/[http://www-ljk.imag.fr/MOISE/AGRIF AGRIF]: starts from the notes of Sebastien, then circulate the powerpoint
+
+ * GMD paper
+
+=== 6) Standard configuration and sanity tests === #a6Standardconfigurationandsanitytests
+The standard configuration should:
+
+ * Include more than one level of embedding (test of the recursive update starting from the finer resolution grid(s))
+
+ * Uses time splitting
+
+ * Include a zoom in a sea ice area (Labrador Sea, LIM3)
+
+ * Include a zoom with PISCES
+
+ * Zoom in Perou Chili
+
+Sanitiy tests
+
+ * Zoom with a mesh refinement of 1
+
+ * Test constancy preservation for tracers
+
+Longer visions of having [http://www-ljk.imag.fr/MOISE/AGRIF AGRIF] zoom in AMM
+
+S coordinates zoom inside a z coordinate parent grid.