# Changing the restart year for branched CM2 ensembles **URL:** \ **Category:** Earth System\ **Tags:** help, access-cm2, restart\ **Created:** [4 December 2024 06:11 UTC](https://forum.access-hive.org.au/t/changing-the-restart-year-for-branched-cm2-ensembles/3961 "2024-12-04T06:11:40Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![hrsdawson](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/hrsdawson/32/218_2.png) [@hrsdawson](https://forum.access-hive.org.au/u/hrsdawson)\ **Post date:** [4 December 2024 06:11 UTC](https://forum.access-hive.org.au/t/changing-the-restart-year-for-branched-cm2-ensembles/3961/1 "2024-12-04T06:11:40Z")
I’m trying to branch some ensembles from the piControl of ACCESS-CM2. My initial attempts, where I modified the `warm restart date` from `09500101` to `10000101` in the Cylc GUI, failed. If I also change the `model basis time` to `10000101`, then the model seems to run (hasn’t failed yet in my current test). I figure though, that this is a very good time to check if there’s anything else I need to pay attention to when changing the restart date? I can’t find much detail about changing restart years in [the instructions](https://access-hive.org.au/models/run-a-model/run-access-cm/#change-run-length-and-cycling-frequency) I’ve been following. Thanks! ---
**Author:** ![Flick.Chun](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/flick.chun/32/2295_2.png) [@Flick.Chun](https://forum.access-hive.org.au/u/Flick.Chun)\ **Post date:** [5 December 2024 05:57 UTC](https://forum.access-hive.org.au/t/changing-the-restart-year-for-branched-cm2-ensembles/3961/2 "2024-12-05T05:57:13Z")
Hello @hrsdawson Thanks for your post, I will try to find an appropriate person to check this. Cheers ---
**Author:** ![spencerwong](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/spencerwong/32/1894_2.png) [@spencerwong](https://forum.access-hive.org.au/u/spencerwong)\ **Post date:** [10 December 2024 22:20 UTC](https://forum.access-hive.org.au/t/changing-the-restart-year-for-branched-cm2-ensembles/3961/3 "2024-12-10T22:20:47Z")
Hi @hrsdawson, it looks like setting setting the `warm restart date` and adjusting the `model basis time` are likely the right steps to take. @MartinDix will double check this and we’ll get back to you! Cheers, Spencer ---
**Author:** ![Aidan](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/aidan/32/42_2.png) [@Aidan](https://forum.access-hive.org.au/u/Aidan)\ **Post date:** [13 December 2024 06:09 UTC](https://forum.access-hive.org.au/t/changing-the-restart-year-for-branched-cm2-ensembles/3961/4 "2024-12-13T06:09:30Z")
Assigned as Spencer has replied ---
**Author:** ![anton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/anton/32/1836_2.png) [@anton](https://forum.access-hive.org.au/u/anton)\ **Post date:** [15 December 2024 23:55 UTC](https://forum.access-hive.org.au/t/changing-the-restart-year-for-branched-cm2-ensembles/3961/5 "2024-12-15T23:55:10Z")
> [@spencerwong](#): > > it looks like setting setting the `warm restart date` and adjusting the `model basis time` are likely the right steps to take. @hrsdawson confirmed this is correct. These dates can be set either “by-hand” in the `rose-suite.conf` file, or through the gui (`rose edit &`). ([Add information on setting "warm restart date" in CM2 · Issue #861 · ACCESS-NRI/access-hive.org.au · GitHub](https://github.com/ACCESS-NRI/access-hive.org.au/issues/861) will add this to the access-hive docs) We did also discover that the restart folder referred to in the CM2 pre-industrial control only has a restart for year 950, 1000 and 1050. There are restarts for every decade in `/g/data/p73/archive/CMIP6/ACCESS-CM2/bi889/restart`, however the restarts for years before 950, and 960, 970 and 980 are missing a CICE field and do not start. ---
**Author:** ![anton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/anton/32/1836_2.png) [@anton](https://forum.access-hive.org.au/u/anton)\ **Post date:** [14 January 2025 21:58 UTC](https://forum.access-hive.org.au/t/changing-the-restart-year-for-branched-cm2-ensembles/3961/6 "2025-01-14T21:58:26Z")