# Versions **URL:** https://nemo-ocean.discourse.group/c/versions/15.md [Latest](https://nemo-ocean.discourse.group/latest.md) · [Categories](https://nemo-ocean.discourse.group/categories.md) · [Tags](https://nemo-ocean.discourse.group/tags.md) --- ## [About the Versions category](https://nemo-ocean.discourse.group/t/about-the-versions-category/206)
**Author:** [@nemo-ocean](https://nemo-ocean.discourse.group/u/nemo-ocean)\ **Replies:** 0
--- ## [\`DOMAINcfg\` settings \`rn\_e3zps\_min\` and \`rn\_e3zps\_rat\` appear inactive](https://nemo-ocean.discourse.group/t/domaincfg-settings-rn-e3zps-min-and-rn-e3zps-rat-appear-inactive/1045)
**Author:** [@d.stephenson](https://nemo-ocean.discourse.group/u/d.stephenson)\ **Replies:** 0\ **Last updated:** [11 September 2026 10:28 UTC](https://nemo-ocean.discourse.group/t/domaincfg-settings-rn-e3zps-min-and-rn-e3zps-rat-appear-inactive/1045 "2026-09-11T10:28:07Z")
Hello, I’m using a fork of 4.2.2 (here) to set up a “hybrid-resolution” simulation using AGRIF, where an eORCA025 domain is the “child” and the “parent” is coarsened by a factor of 3 (i.e. 0.75 degree), as in described h… --- ## [\[v.4.0.x\] Instability error and "p4zopt.f90" crash issue that occur on the same day](https://nemo-ocean.discourse.group/t/v-4-0-x-instability-error-and-p4zopt-f90-crash-issue-that-occur-on-the-same-day/312)
**Author:** [@Jin](https://nemo-ocean.discourse.group/u/Jin)\ **Replies:** 2\ **Last updated:** [24 August 2026 05:41 UTC](https://nemo-ocean.discourse.group/t/v-4-0-x-instability-error-and-p4zopt-f90-crash-issue-that-occur-on-the-same-day/312 "2026-08-24T05:41:06Z")
Dear all, I have set up ORCA2\_ICE\_PISCES in NEMO v4.0.6 using gfortran compiler. I met two significant errors for running model, which are the instability error and the p4zopt.f90 crash issue. I solved the problem temp… --- ## [\[v4.0.x\] \*p4zopt.f90\* crash: out of lower bound value for \`rkrgb\`](https://nemo-ocean.discourse.group/t/v4-0-x-p4zopt-f90-crash-out-of-lower-bound-value-for-rkrgb/290)
**Author:** [@ukocean](https://nemo-ocean.discourse.group/u/ukocean)\ **Replies:** 3\ **Last updated:** [24 August 2026 05:21 UTC](https://nemo-ocean.discourse.group/t/v4-0-x-p4zopt-f90-crash-out-of-lower-bound-value-for-rkrgb/290 "2026-08-24T05:21:51Z")
Dear users, I’m trying to run r4.0.7 version of nemo using r05 resolution and get the error message: forrtl: severe (408): fort: (3): Subscript #2 of the array RKRGB has value "-2147483648" which is less than the lower… --- ## [Heat fluxes in NEMO and LIM 2](https://nemo-ocean.discourse.group/t/heat-fluxes-in-nemo-and-lim-2/1043)
**Author:** [@danaking](https://nemo-ocean.discourse.group/u/danaking)\ **Replies:** 0\ **Last updated:** [17 August 2026 15:12 UTC](https://nemo-ocean.discourse.group/t/heat-fluxes-in-nemo-and-lim-2/1043 "2026-08-17T15:12:05Z")
Hello, I am very new to working with a reanalysis model and still trying to understand how everything is connected. I am using the GLORYS model on the ORCA grid, which uses the NEMO ocean model (something between versio… --- ## [Output problem with NEMO-PISCES 4.2.3 + XIOS 2.5 users tracer](https://nemo-ocean.discourse.group/t/output-problem-with-nemo-pisces-4-2-3-xios-2-5-users-tracer/1042)
**Author:** [@Pysh](https://nemo-ocean.discourse.group/u/Pysh)\ **Replies:** 0\ **Last updated:** [8 August 2026 11:41 UTC](https://nemo-ocean.discourse.group/t/output-problem-with-nemo-pisces-4-2-3-xios-2-5-users-tracer/1042 "2026-08-08T11:41:55Z")
Hello! I’m having trouble solving this problem. Nemo 4.2.3 + XIOS 2.5. ORCA2-PISCES configuration. I’m trying to run a task for user passive tracer with source data from an external file. When outputting the tracer conc… --- ## [The vertical diffusion trend term has issues (utrd\_zdf/vtrd\_zdf)](https://nemo-ocean.discourse.group/t/the-vertical-diffusion-trend-term-has-issues-utrd-zdf-vtrd-zdf/1036)
**Author:** [@corentingnt](https://nemo-ocean.discourse.group/u/corentingnt)\ **Replies:** 1\ **Last updated:** [2 July 2026 16:50 UTC](https://nemo-ocean.discourse.group/t/the-vertical-diffusion-trend-term-has-issues-utrd-zdf-vtrd-zdf/1036 "2026-07-02T16:50:44Z")
Hi, We do this message with Véga, trainee with Julie Deshayes and myself at Locean (I am PhD student). We looked at different trends terms in the NEMO.4.0 version. We noticed an issue with utrd\_zdf and vtrd\_zdf, that se… --- ## [NEMO 5.0 - XIOS 3 hangs at initialization](https://nemo-ocean.discourse.group/t/nemo-5-0-xios-3-hangs-at-initialization/858)
**Author:** [@Luc](https://nemo-ocean.discourse.group/u/Luc)\ **Replies:** 3\ **Last updated:** [17 June 2026 11:08 UTC](https://nemo-ocean.discourse.group/t/nemo-5-0-xios-3-hangs-at-initialization/858 "2026-06-17T11:08:35Z")
Hello, When I run my NEMO 5.0 config with XIOS 2, it runs fine. I’m trying to switch to XIOS 3. My main motivation is to have less writers, as the cluster admins always complain I have too many disk access. I copied t… --- ## [Turning on ln\_cfc11, cfc12 and sf6](https://nemo-ocean.discourse.group/t/turning-on-ln-cfc11-cfc12-and-sf6/1023)
**Author:** [@ErikBuitenhuis](https://nemo-ocean.discourse.group/u/ErikBuitenhuis)\ **Replies:** 0\ **Last updated:** [2 June 2026 13:12 UTC](https://nemo-ocean.discourse.group/t/turning-on-ln-cfc11-cfc12-and-sf6/1023 "2026-06-02T13:12:24Z")
I’m trying to turn on ln\_cfc11, ln\_cfc12 and ln\_sf6 in NEMO\_v5.0. Does anyone have an atmospheric forcing file in the format it expects, and matching namelist\_trc\_ref and/or namelist\_trc\_cfg? Thanks, Erik e031@uea.ac.… --- ## [AGRIF doesn't compile with gcc15 due to conflicting types](https://nemo-ocean.discourse.group/t/agrif-doesnt-compile-with-gcc15-due-to-conflicting-types/1022)
**Author:** [@Franziska](https://nemo-ocean.discourse.group/u/Franziska)\ **Replies:** 4\ **Last updated:** [12 May 2026 09:21 UTC](https://nemo-ocean.discourse.group/t/agrif-doesnt-compile-with-gcc15-due-to-conflicting-types/1022 "2026-05-12T09:21:27Z")
Hi, when compiling an AGRIF configuration (e.g. AGRIF\_DEMO) using GCC 15 (which appears to be more restrict than previous versions) it fails with the following error message: .../nemo/ext/AGRIF/LIB/UtilFortran.c:266:6:… --- ## [Bug on gridcells with only 1 vertical layer](https://nemo-ocean.discourse.group/t/bug-on-gridcells-with-only-1-vertical-layer/1019)
**Author:** [@SimonSD](https://nemo-ocean.discourse.group/u/SimonSD)\ **Replies:** 0\ **Last updated:** [7 May 2026 20:14 UTC](https://nemo-ocean.discourse.group/t/bug-on-gridcells-with-only-1-vertical-layer/1019 "2026-05-07T20:14:03Z")
When I use the same bathymetric grid as I was using with NEMO 3.6, but with NEMO 4.2.2, the model aborts after a certain number of timesteps because SSH \>= 20m at one gridpoint. It appears that this gridpoint has just on… --- ## [North fold bug? Artefact along north fold in sea ice variables](https://nemo-ocean.discourse.group/t/north-fold-bug-artefact-along-north-fold-in-sea-ice-variables/972)
**Author:** [@jraylmer](https://nemo-ocean.discourse.group/u/jraylmer)\ **Replies:** 15\ **Last updated:** [17 April 2026 10:12 UTC](https://nemo-ocean.discourse.group/t/north-fold-bug-artefact-along-north-fold-in-sea-ice-variables/972 "2026-04-17T10:12:01Z")
I run ORCA2-ICE simulations and often see artefacts in output variables along the grid cells where north-folding occurs. It sometimes takes several years before it appears, depending on the forcing and namelist settings.… --- ## [Best practices for NetCDF forcing files to avoid continuous disk reads (chunking / unlimited time / compression)?](https://nemo-ocean.discourse.group/t/best-practices-for-netcdf-forcing-files-to-avoid-continuous-disk-reads-chunking-unlimited-time-compression/997)
**Author:** [@mchoblet](https://nemo-ocean.discourse.group/u/mchoblet)\ **Replies:** 8\ **Last updated:** [24 March 2026 13:33 UTC](https://nemo-ocean.discourse.group/t/best-practices-for-netcdf-forcing-files-to-avoid-continuous-disk-reads-chunking-unlimited-time-compression/997 "2026-03-24T13:33:47Z")
Hello, I’m looking for advice / best practices on NetCDF formatting of NEMO input forcing files to reduce unnecessary I/O on I/O-limited, shared HPC systems (parallel filesystem, multiple users running at once). Contex… --- ## [Advise on masking of ice thickness in XIOS for CMIP7 and intensive sea ice variables](https://nemo-ocean.discourse.group/t/advise-on-masking-of-ice-thickness-in-xios-for-cmip7-and-intensive-sea-ice-variables/982)
**Author:** [@Jsterlin](https://nemo-ocean.discourse.group/u/Jsterlin)\ **Replies:** 3\ **Last updated:** [20 March 2026 07:52 UTC](https://nemo-ocean.discourse.group/t/advise-on-masking-of-ice-thickness-in-xios-for-cmip7-and-intensive-sea-ice-variables/982 "2026-03-20T07:52:02Z")
Dear NEMO community, I’m reviewing the definition of the effective ice thickness (not the volume) in XIOS in preparation for CMIP7. There are currently two main definitions in field\_def\_nemo-ice.xml: - icethic: https:/… --- ## [Output NEMO sections / transects. DIADCT](https://nemo-ocean.discourse.group/t/output-nemo-sections-transects-diadct/1001)
**Author:** [@joakim](https://nemo-ocean.discourse.group/u/joakim)\ **Replies:** 3\ **Last updated:** [17 March 2026 17:47 UTC](https://nemo-ocean.discourse.group/t/output-nemo-sections-transects-diadct/1001 "2026-03-17T17:47:08Z")
Good afternoon I’d like to output the transport through sections from NEMO 4.2. I’ve made the “sections” file using the SECTIONS tool and set ln\_diadct = .true. in the namelist. But when I run, I get an error from XIOS… --- ## [AGRIF memory allocation errors when compiled with gnu (NEMO 5)](https://nemo-ocean.discourse.group/t/agrif-memory-allocation-errors-when-compiled-with-gnu-nemo-5/984)
**Author:** [@Franziska](https://nemo-ocean.discourse.group/u/Franziska)\ **Replies:** 3\ **Last updated:** [13 March 2026 05:49 UTC](https://nemo-ocean.discourse.group/t/agrif-memory-allocation-errors-when-compiled-with-gnu-nemo-5/984 "2026-03-13T05:49:14Z")
Dear NEMO community, we have a rather big AGRIF configuration which runs when compiled with intel but fails using gnu compilers, which we would like to use due to a series of issues with intel (e.g. this ticket and more… --- ## [Bug in the sign convention in the TKE OSBL scheme?](https://nemo-ocean.discourse.group/t/bug-in-the-sign-convention-in-the-tke-osbl-scheme/998)
**Author:** [@takachanbo](https://nemo-ocean.discourse.group/u/takachanbo)\ **Replies:** 0\ **Last updated:** [6 March 2026 08:29 UTC](https://nemo-ocean.discourse.group/t/bug-in-the-sign-convention-in-the-tke-osbl-scheme/998 "2026-03-06T08:29:52Z")
I am looking through the turbulent kinetic energy (TKE) ocean surface boundary layer (OSBL) scheme but I am having some confusions pertaining to the term associated with Kolmogorov dissipation. In the snippet of code fro… --- ## [XIOS compilation failure with parallel NetCDF (undefined reference to nc\_\*) – linux\_openmpi](https://nemo-ocean.discourse.group/t/xios-compilation-failure-with-parallel-netcdf-undefined-reference-to-nc-linux-openmpi/994)
**Author:** [@nhidayat](https://nemo-ocean.discourse.group/u/nhidayat)\ **Replies:** 0\ **Last updated:** [28 February 2026 02:51 UTC](https://nemo-ocean.discourse.group/t/xios-compilation-failure-with-parallel-netcdf-undefined-reference-to-nc-linux-openmpi/994 "2026-02-28T02:51:01Z")
Dear all, I want to install NEMO mode on my laptop but got a few problems in the process. I am trying to build XIOS2 with parallel NetCDF support on Ubuntu, but the compilation fails during the linking stage with multi… --- ## [Xios : diamlr output not working in parrallel](https://nemo-ocean.discourse.group/t/xios-diamlr-output-not-working-in-parrallel/993)
**Author:** [@gdenoordhout](https://nemo-ocean.discourse.group/u/gdenoordhout)\ **Replies:** 0\ **Last updated:** [26 February 2026 19:04 UTC](https://nemo-ocean.discourse.group/t/xios-diamlr-output-not-working-in-parrallel/993 "2026-02-26T19:04:45Z")
Dear all, I am currently running a NEMO4.2.1 configuration on the North Sea (based on AMM7 developed by the Met Office). For my tidal analysis, I activated the diamlr output (regrouping all the regressors for each tidal… --- ## [WEIGHTS produces bad values](https://nemo-ocean.discourse.group/t/weights-produces-bad-values/438)
**Author:** [@m-n-o](https://nemo-ocean.discourse.group/u/m-n-o)\ **Replies:** 9\ **Last updated:** [24 February 2026 12:47 UTC](https://nemo-ocean.discourse.group/t/weights-produces-bad-values/438 "2026-02-24T12:47:45Z")
Hello again.) To initialize the model (global ORCA2), I use the global ocean analysis and forecast 1/12 degree data from CMEMS. There are no runtime errors when creating weights using the WEIGHTS tool from the dataset c… --- ## [DOMAINcfg: NetCDF: Index exceeds dimension bound](https://nemo-ocean.discourse.group/t/domaincfg-netcdf-index-exceeds-dimension-bound/986)
**Author:** [@erru](https://nemo-ocean.discourse.group/u/erru)\ **Replies:** 3\ **Last updated:** [13 February 2026 07:12 UTC](https://nemo-ocean.discourse.group/t/domaincfg-netcdf-index-exceeds-dimension-bound/986 "2026-02-13T07:12:16Z")
Hi All, I am having a hard time with generating a domain file with the tool DOMAINcfg This is my namelist\_cgf !!\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\>\> !! NEMO/OCE Configuration namelis… --- ## [ERROR: AGRIF hot start requires to force Euler first step on parent](https://nemo-ocean.discourse.group/t/error-agrif-hot-start-requires-to-force-euler-first-step-on-parent/978)
**Author:** [@wangy](https://nemo-ocean.discourse.group/u/wangy)\ **Replies:** 1\ **Last updated:** [14 January 2026 15:52 UTC](https://nemo-ocean.discourse.group/t/error-agrif-hot-start-requires-to-force-euler-first-step-on-parent/978 "2026-01-14T15:52:50Z")
Hi everyone I have been running a 10-year nested case. The AGRIF.in file is as follows. 1 172 196 62 92 2 2 2 1 10 41 15 46 3 3 3 0 Now, when I try to restart it, 1\_ocean.output\_00\* and 2\_ocean.output\_00\* both … --- ## [MPI freezes sporadically with intel oneAPI on a large configuration, often inside a call to XIOS](https://nemo-ocean.discourse.group/t/mpi-freezes-sporadically-with-intel-oneapi-on-a-large-configuration-often-inside-a-call-to-xios/973)
**Author:** [@dupontf](https://nemo-ocean.discourse.group/u/dupontf)\ **Replies:** 4\ **Last updated:** [7 January 2026 12:02 UTC](https://nemo-ocean.discourse.group/t/mpi-freezes-sporadically-with-intel-oneapi-on-a-large-configuration-often-inside-a-call-to-xios/973 "2026-01-07T12:02:22Z")
Hi, I am running a large ~4800x6600 configuration on ~4000 cores and 160 XIOS cores but sporadically get a time-out and trace it back to a MPI operation (mpi\_allreduce or mpi\_probe) inside the model or XIOS, although mos… --- ## [NaNs appearing in model domain](https://nemo-ocean.discourse.group/t/nans-appearing-in-model-domain/971)
**Author:** [@tmwilder](https://nemo-ocean.discourse.group/u/tmwilder)\ **Replies:** 4\ **Last updated:** [12 December 2025 11:52 UTC](https://nemo-ocean.discourse.group/t/nans-appearing-in-model-domain/971 "2025-12-12T11:52:11Z")
Hi, I am trying to spin up the DINO configuration at 1/16 degree in nemo v4.2.1. My method is to run NEMO for x years, rebuild the restart file at year x, then pickup NEMO from that restart point, and repeat. The probl… --- ## [Compiling NEMO 5.x with a nested domain](https://nemo-ocean.discourse.group/t/compiling-nemo-5-x-with-a-nested-domain/966)
**Author:** [@qtqw](https://nemo-ocean.discourse.group/u/qtqw)\ **Replies:** 1\ **Last updated:** [11 December 2025 15:57 UTC](https://nemo-ocean.discourse.group/t/compiling-nemo-5-x-with-a-nested-domain/966 "2025-12-11T15:57:59Z")
I am trying to compile NEMO 5.x with a nested domain, but I do not need TOP and ICE modules. As far as I understand I should use ./makenemo -m linux\_ifort -r AGRIF\_DEMO -n MY\_OCE\_agrif -j 8 del\_key “key\_top key\_si3” I… --- ## [Type mismatch between actual argument at (1) and actual argument at (2) (REAL(8)/CHARACTER(\*))](https://nemo-ocean.discourse.group/t/type-mismatch-between-actual-argument-at-1-and-actual-argument-at-2-real-8-character/968)
**Author:** [@erru](https://nemo-ocean.discourse.group/u/erru)\ **Replies:** 2\ **Last updated:** [10 December 2025 00:48 UTC](https://nemo-ocean.discourse.group/t/type-mismatch-between-actual-argument-at-1-and-actual-argument-at-2-real-8-character/968 "2025-12-10T00:48:13Z")
Where is this error coming from? I can’t find a workaorund for this one. mpif90 -c -cpp -o trc\_oce.o -I/home/sustain-biome/Desktop/nemo\_4.2.2/cfgs/MY\_GYRE/BLD/inc -fdefault-real-8 -O3 -funroll-all-loops -fcray-pointer -… --- ## [Ifx v2025.3.0 compilers -O2 optimisation breaks fldread for unstructured boundaries](https://nemo-ocean.discourse.group/t/ifx-v2025-3-0-compilers-o2-optimisation-breaks-fldread-for-unstructured-boundaries/967)
**Author:** [@RobMc](https://nemo-ocean.discourse.group/u/RobMc)\ **Replies:** 0\ **Last updated:** [2 December 2025 17:15 UTC](https://nemo-ocean.discourse.group/t/ifx-v2025-3-0-compilers-o2-optimisation-breaks-fldread-for-unstructured-boundaries/967 "2025-12-02T17:15:14Z")
I’m using NEMO v4.0 but I don’t think fldread has changed since then. The issue occurs when using the intel ifx v2025.3.0 compiler with -O2 optimisation and unstructured boundaries and 256 cpus. In subroutine fld\_map\_cor… --- ## [How to make the subbasins.nc file for NEMO 4.2.2?](https://nemo-ocean.discourse.group/t/how-to-make-the-subbasins-nc-file-for-nemo-4-2-2/861)
**Author:** [@joakim](https://nemo-ocean.discourse.group/u/joakim)\ **Replies:** 4\ **Last updated:** [21 November 2025 13:40 UTC](https://nemo-ocean.discourse.group/t/how-to-make-the-subbasins-nc-file-for-nemo-4-2-2/861 "2025-11-21T13:40:40Z")
Good morning I’m setting up a new configuration with NEMO 4.2.2 and generating the domain\_cfg.nc with the DOMAINcfg tool. So far so good, but I’m missing the subbasins.nc file needed to compute zonal means and MOC for t… --- ## [Domain\_cfg in nemo 5 resulting a shift in cell](https://nemo-ocean.discourse.group/t/domain-cfg-in-nemo-5-resulting-a-shift-in-cell/965)
**Author:** [@saad](https://nemo-ocean.discourse.group/u/saad)\ **Replies:** 0\ **Last updated:** [10 November 2025 16:07 UTC](https://nemo-ocean.discourse.group/t/domain-cfg-in-nemo-5-resulting-a-shift-in-cell/965 "2025-11-10T16:07:18Z")
Hello, I am migrating from nemo 3.6 to nemo 5. in my nemo 3.6 namelist, when i would specify: namelist: ppglam0 = -18.125 ! longitude of first raw and column T-point (jphgr\_msh = 1) ppgphi0 = 30… --- ## [Time stepping procedure and split-explicit method](https://nemo-ocean.discourse.group/t/time-stepping-procedure-and-split-explicit-method/964)
**Author:** [@gdenoordhout](https://nemo-ocean.discourse.group/u/gdenoordhout)\ **Replies:** 0\ **Last updated:** [9 November 2025 13:16 UTC](https://nemo-ocean.discourse.group/t/time-stepping-procedure-and-split-explicit-method/964 "2025-11-09T13:16:18Z")
Dear, I am currently trying to understand in details how the time stepping procedure does work in Nemo 4.2.1 when using the modified Leapfrog algorithm with a non-linear split-explicit free surface. First, I wonder if … [Next page](https://nemo-ocean.discourse.group/c/versions/15.md?page=1)