# Session 6: Breakout room 3: Model Configurations/ development - ACCESS-CM3/ESM3 **URL:** \ **Category:** CMIP7 Workshop\ **Tags:** workshop, cmip7\ **Created:** [1 March 2023 00:00 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507 "2023-03-01T00:00:06Z")\ **Posts on this page:** 20\ **Page:** 2
**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:** [1 March 2023 01:13 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/21 "2023-03-01T01:13:05Z")
TZ: also aspire to use a common codebase with various config options ---
**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:** [1 March 2023 01:14 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/22 "2023-03-01T01:14:49Z")
MC: re WOMBAT: ESM1.5 took spun-up physics, then tuned, then spunup again for ~1000yr. ESM3 in this timeline looks unrealistically ambitious to fit CMIP7 timeline ---
**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:** [1 March 2023 01:16 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/23 "2023-03-01T01:16:39Z")
PS: re. COSIMA switching priorities to global low res - would this be using ACCESS-NRI resources? What about high res? AH: if there’s a need for global model for CM3, switch priorities around to get global working sooner ---
**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:** [1 March 2023 01:18 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/24 "2023-03-01T01:18:08Z")
TZ: aim for 0.25 (not 0.1) deg ocean in CM3 and GL9 atmosphere - what computational resources are needed? ---
**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:** [1 March 2023 01:23 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/25 "2023-03-01T01:23:45Z")
AK: COSIMA is large in terms of people keen to do the scientific assessment and applications but stretched for people to do the technical work. AH: ACCESS-NRI hasn’t yet hired all ocean engineers; but they would work in same direction as COSIMA ---
**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:** [1 March 2023 01:27 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/26 "2023-03-01T01:27:44Z")
BE: do we need ESM for CMIP7? TZ: yes definitely need ESM for CMIP7. Might get a coupled model in time for CMIP7 but maybe not a carbon cycle; so would need a different codebase for ESM; separate spinup; split resources HR: what time is needed to put in a carbon cycle - what coding? TZ: may need to wait until all other components in place before add carbon cycle ?: increasing resolution requires recalibration - hence another spinup - no saving of dev time ---
**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:** [1 March 2023 01:29 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/27 "2023-03-01T01:29:39Z")
AH: last time we needed a split approach - hedging bets - was that the right strategy? ?: CABLE issues in CM3 - would have failed to get ESM2, then run out of time to get ESM1.5 MD: wouldn’t have got a ESM2 ---
**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:** [1 March 2023 01:30 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/28 "2023-03-01T01:30:51Z")
TZ: ESM1.5 was put together to get an ESM but needed to use old UM etc. For CMIP7 if we need a fallback, consider ESM2 based on CM2 ---
**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:** [1 March 2023 01:31 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/29 "2023-03-01T01:31:31Z")
?: ESM2 is technically working; no scientific assessment of output as yet ---
**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:** [1 March 2023 01:31 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/30 "2023-03-01T01:31:50Z")
SM: are we saying ESM3+ is not an option? ---
**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:** [1 March 2023 01:33 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/31 "2023-03-01T01:33:10Z")
ME: CMIP makes us risk-averse. One over-ambitious option could be fatal; one safe option doesn’t advance capability; we have to have 2 approaches even though it splits resources etc ---
**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:** [1 March 2023 01:33 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/32 "2023-03-01T01:33:43Z")
HR: covered both bases by having 2 approaches in CMIP6 ---
**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:** [1 March 2023 01:34 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/33 "2023-03-01T01:34:53Z")
BGF: what’s the soonest date for stable CMIP7-ready ESM release? re. sovereign capability - we need to be pushing the teach forward and adopting new innovations ---
**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:** [1 March 2023 01:35 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/34 "2023-03-01T01:35:46Z")
MD: deep ocean drifts in MOM5 - will this be an issue in MOM6? TZ: takes ~5000yr spinup to find out ---
**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:** [1 March 2023 01:36 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/35 "2023-03-01T01:36:17Z")
TZ: throughput is much better in ESM1.5 - supports long simulations and large ensembles ---
**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:** [1 March 2023 01:36 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/36 "2023-03-01T01:36:54Z")
SO: radiation balance issues -a priority for met office ---
**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:** [1 March 2023 01:38 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/37 "2023-03-01T01:38:27Z")
AH: the deep ocean adjustment would be due to Antarctic shelf processes, AABW, in ocean-only and this is faster (in model years, not walltime) at high resolution. Unclear how this will look in MOM6. And can’t go to this high resolution and keep model speed. ---
**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:** [1 March 2023 01:39 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/38 "2023-03-01T01:39:11Z")
BGF: gold standard is a stable release and a dev release ---
**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:** [1 March 2023 01:40 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/39 "2023-03-01T01:40:36Z")
AH: we have a backstop: ESM2 TZ: does this fill community needs? Also still issues to sort out with CM2 before we add BGC ---
**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:** [1 March 2023 01:41 UTC](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507/40 "2023-03-01T01:41:18Z")
TZ: old UM is losing credibility - need to keep up to date [Previous page](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507.md?page=1) [Next page](https://forum.access-hive.org.au/t/session-6-breakout-room-3-model-configurations-development-access-cm3-esm3/507.md?page=3)