# Ice restart dates in OM2

**URL:** <https://forum.access-hive.org.au/t/ice-restart-dates-in-om2/6988>\
**Category:** Technical\
**Tags:** help, payu\
**Created:** [15 September 2026 05:01 UTC](https://forum.access-hive.org.au/t/ice-restart-dates-in-om2/6988 "2026-09-15T05:01:39Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![ongqingyee](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/ongqingyee/32/126_2.png) [@ongqingyee](https://forum.access-hive.org.au/u/ongqingyee)\
**Post date:** [15 September 2026 05:01 UTC](https://forum.access-hive.org.au/t/ice-restart-dates-in-om2/6988/1 "2026-09-15T05:01:39Z")

</div>

hello! I am trying to use some restart files that were recently generated and there are some issues I’ve not seen before. After the model has completed its run to the final time step (seen in work/atmosphere/log/matmxx.pe00000.log), I get this in accessom2.err.

```auto
Error in accessom2_deinit: atm and ice models are out of sync.
atm end date: 2000-02-01T00:00:00.000
ice end date: 2020-02-01T00:00:00.000

```

My accessom2.nml dates and forcing dates align, otherwise it wouldn’t run. The ice restart file names are also okay, the file names of the restart are below:

```auto
[qo9901@gadi-login-09 1deg_restart_test]$ ls /home/561/qo9901/access-om2/1deg_esm1p5_vgrid_fric_mo_i2o/archive/restart019/ice/
grid.nc i2o.nc iced.2000-01-01-00000.nc ice.restart_file kmt.nc monthly_sstsss.nc o2i.nc sicemass.nc u_star.nc

```

I will note that for the iced.2000-01-01-00000.nc file, these are the global attributes, which are line up with the run I did originally. This is the only place I see where the year ~20 comes up.

```auto
// global attributes:
		:istep1 = 116880 ;
		:time = 631152000. ;
		:time_forc = 0. ;
		:nyr = 21 ;
		:month = 1 ;
		:mday = 1 ;
		:sec = 0 ;
}

```

The `ice.restart_file`is also the year 2000 as expected, so it looks like a cice inbuilt problem, where nyr is not being changed? Not sure if I’ve missed something, but want to check before manually rewriting the attrs, or if there is a long term solution if restarting from other experiments. (I have tried with and without using `payu clone --restart <dir>`, and also changing `runtype = 'continue'` in `cice_in.nml` but no luck)

Exp dir: /home/561/qo9901/access-om2/1deg\_restart\_test  
Restart dir: /home/561/qo9901/access-om2/1deg\_esm1p5\_vgrid\_fric\_mo\_i2o/archive/restart019/

Thank you! and tagging some who might be able to answer this with eyes closed @aidan, @anton

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<div class="post-metadata">

**Author:** ![aekiss](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/aekiss/32/46_2.png) [@aekiss](https://forum.access-hive.org.au/u/aekiss)\
**Post date:** [15 September 2026 06:59 UTC](https://forum.access-hive.org.au/t/ice-restart-dates-in-om2/6988/2 "2026-09-15T06:59:33Z")

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Maybe try setting `use_restart_time = .false.` in `ice/cice_in.nml`?

If it runs, set it back to true for the subsequent runs.

See [Tutorials · COSIMA/access-om2 Wiki · GitHub](https://github.com/COSIMA/access-om2/wiki/Tutorials#more-complicated-cases)

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<div class="post-metadata">

**Author:** ![ongqingyee](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/ongqingyee/32/126_2.png) [@ongqingyee](https://forum.access-hive.org.au/u/ongqingyee)\
**Post date:** [15 September 2026 10:54 UTC](https://forum.access-hive.org.au/t/ice-restart-dates-in-om2/6988/3 "2026-09-15T10:54:22Z")

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thank you andrew!