# Meeting Minutes 2025: Atmosphere Working Group (Achived)

**URL:** <https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149>\
**Category:** Working Group\
**Created:** [12 February 2025 01:40 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149 "2025-02-12T01:40:39Z")\
**Posts on this page:** 9\
**Page:** 1

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**Author:** ![heidi](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/heidi/32/335_2.png) [@heidi](https://forum.access-hive.org.au/u/heidi)\
**Post date:** [12 February 2025 01:40 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/1 "2025-02-12T01:40:39Z")

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Notes from each meeting of the Atmosphere Working Group held in 2025 are added as a reply to this topic.

Make each reply a [wiki post](https://meta.discourse.org/t/what-is-a-wiki-post/30801), that way other attendees can edit the notes. This can greatly reduce the burden of note-taking allowing that person to participate fully in discussions without worrying too much about missing important details.

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**Author:** ![cbengel](https://avatars.discourse-cdn.com/v4/letter/c/ce7236/32.png) [@cbengel](https://forum.access-hive.org.au/u/cbengel)\
**Post date:** [12 February 2025 02:48 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/2 "2025-02-12T02:48:28Z")

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**Atmosphere WG Meeting 12.02.2025 minutes**  
12 Feb 2025  
26 participants on Zoom  
From: UNSW, BoM, Monash, ACCESS-NRI, CSIRO, UTas

**Science talk** – **Free-running tests with the NRI-version of the Regional Nesting Suite** by _Matt Lipson_

- Mat mentioned that the talk would be more technical than scientific talk due to where we are at. Using Spare SU last year, Mat pulled together ancillaries and ran nested 1km simulations centered over Sydney.

- Different setup to ACCESS-NRI Lismore tutorial.

- Results:

- Concluding remarks: Thinking about reducing size of outer domain or removing 5km domain. Suite is easy to run; hardest part is setting up STASH. There is no automatic conversion to netcdf, but there are ACCESS-NRI tools available (e.g., um2nc) which could work for the regional suite. Mat and Chermelle are talking about a GCM-driven nesting suite.  
For details about setup see [this GitHub page](https://github.com/21centuryweather/RNS_Sydney_1km).

- Questions/Answers

**Tech talk** – **An introduction to ACCESS-Vis: Visualisation tools released to date and current work in progress** by _Owen Kaluza_

- Yi introduced Owen: “If you want to make your data come to life, Owen is a person who can show you the tricks”.  
Owen is a senior Research Software Engineer working in the MedTeam at ACCESS-NRI, specialising in visualisation. His aim is to produce showpiece visualisations for ACCESS-NRI.  
He tends to work in python and uses tools that researchers use; focus on open-source tools.  
Also uses GPU acceleration.

- There are three repositories:

- Questions/Answers:

**2025 ACCESS Workshop:** _Heidi Nettelbeck_ (5-10mins)

- This year the workshop will be held in Melbourne in early September. The workshop committee would like to schedule parallel science sessions. The Working Group would like to hear from the Atmosphere community what those sessions could look like. Any ideas?  
You can also post comments on the forum.

- Comments:

**Compute/storage resources - Atmosphere WG:** _Heidi Nettelbeck_

- Any Experiment proposals for Q1/2025? We have 875 kSU allocation this quarter.  
Heidi gave a demo on [how to apply for Atmosphere WG Resources](https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fforum.access-hive.org.au%2Ft%2Fapplying-for-atmosphere-wg-resources%2F844&data=05%7C02%7Cu1151657%40anu.edu.au%7C7a42bd0ea57d47b7fc5a08dd45899636%7Ce37d725cab5c46249ae5f0533e486437%7C0%7C0%7C638743179446158473%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=Lbmr20Ed9JUL6jWn18oK2exlM5NugvRygM%2BiPRrG50I%3D&reserved=0).

**Next Atmosphere WG meeting:**

- _19 March 2025 @ 11:30am_

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**Author:** ![Paul.Gregory](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/paul.gregory/32/2566_2.png) [@Paul.Gregory](https://forum.access-hive.org.au/u/Paul.Gregory)\
**Post date:** [20 March 2025 05:49 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/3 "2025-03-20T05:49:35Z")

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### Atmosphere WG Meeting 19.03.2025 minutes

19 March 2025  
27 participants on Zoom  
Matt Woodhouse convening.

**Updates from WG Chairs.**  
_Heidi:_

- ACCESS-NRI are about to release a configuration of the Regional Nesting Suite _ACCESS-rAM3_ (beta release).

_Charmaine:_

- New starter at BoM. Ian White. Working on ACCESS-A/AE km scale systems.
- Working with met office on RAL3/Lfric. Lfric is the replacement for the UM. We will be running that RAL3 for three domains for high impact weather case studies.

_Yi:_

- AUS2200 project research is ongoing using the model datasets. Black summer case study has been published in JGR atmosphere. The first major publication from the AUS2200 data. Other papers are in draft. Thanks for the community support.
- In 21stCenturyWeather we are discussing running larger simulations. A ‘flagship’ simulation using NRI and rAM3. Discussions are ongoing.
- Trying to get AM3 running with Cable at ~25 km spacing (N512). Cable ancillaries are currently only available at 1 degrees.
- We have some new ECRs.
  - Ian W. Originally from the UK, now at BoM w/Charmaine.
  - Qingqand Gao. From Cambridge PhD, now post-doc with Yi at Unimelb. Looking at low clouds in hi-res, convective permitting models. Looking at BARRA-R2 and C2. Working with Chun-Hsu at BoM.
  - Alanah Chapman. Working with Yi, Matt, Robyn and Sonya on AM3. Looking at southern ocean clouds, specifically sources of dimethyl sulphide and sea ice melt.
  - Nasim Aln. Starting post-doc with Steven Zim and Monash. Wanting to run ACCESS-UM examining convection schemes and transition from shallow to open convection.
  - ANU students Emma, et al. working with Sarah Perkins-Kirkpatrick.

**Topics for ACCESS workshop in September 2025:**  
_Jasmeen:_

- User training team at ACCESS-NRI has created a [training topics poll](https://forum.access-hive.org.au/t/2025-access-training-day-what-should-we-offer/4259)
- Please fill out - should take only 2-3 minutes. Feedback is greatly appreciated!

Comment From Paul Leopardi :

- Looking for extra technical requests/ material for training days for breakout rooms. UKMO is upgrading suites to cylc8 and Github. Fab etc. The Momentum User workshop runs before ours, these will be included in our community workshop.

**Christian Stassen science talk: Added value (AV) of regional models over Australia**

- RCMs improve many outputs from GCMs.
- But they have their own set of problems, i.e. the remaining parameterisations.
- RCMs over Australia are still not km-scale convection resolving.
- Comparing BARPA-R (~17 km) and CCAM12 (~12.5 km), both with model tops at ~40 km, against ERA5 + 8 X CMIP6 models downscaled
- Comparing GCM and RCM historical runs against observations from 1985-2014, looking at MSE, bias and correlation.
- Looking at metrics at two different length scales to avoid double-penalty problem (e.g. penalised with spatial error sin extreme precipitation events at higher resolution, which GCMs can’t even simulate)
- We upscale RCM to GCM, and interpolate GCM to RCM.
- Looking at Hot, cold, wet and dry extremes.
- RCM improves tasmax over most of Australia, but struggles with Tmin and precip over SE Australia
- Generally BARPA and CCAM add value at GCM scale. ‘Drizzle problem’ in GCM is improved, so RCMs give AV in number of drought days.
- BARPA and CCAM add vallue at RCM length scale.

Q : Martin. Can you say whether RCMs make bad GCMs less bad, and good GCMs better?

A: Not much AV for ERA5 and Euro-Earth as these are already at fairly hi-res. We do improve MPI models but some biases (e.g. cold bias) can’t be removed by CCAM. It is metric and model dependent.

Q : Matt. A preprint yet?  
A: Don’t know. I’ve been away for the past week! Will let you know.

Matt - a preprint in the minutes would be great.

**Paul Gregory : Showing 21st Century Weather Wiki on introductory rose/cylc training for new ACCESS-UM users.**

See [Introduction to Rose/Cylc — 21st Century Weather Software Wiki](https://21centuryweather.github.io/21st-Century-Weather-Software-Wiki/rose-cylc/rose-cylc-intro.html)

Q : Chermelle. Be careful with out suite ids. Please remove Scott’s suite and waite for rAM3.  
A : Sure, no probs.

Q : Davide. Overlapping with NRI and Hive docs.  
A : Will link to existing documentation where ever possible so there is only one, supported and maintained, source of truth within the community.

Q : Heidi. Reach out to me and Davide as we maintain the Hive docs.  
Q : Paul L. Keep in mind migration , e.g. cycl 8 and github, rosie migration.

**Martin Dix : AM3 updates**

- Uses updated UM and CABLE and will eventually become ESM3
- Using GM GA9 with CABLE instead of JULES.
- Running at N96. Issues with CABLE ancilliary generation at higher resolution.
- Unifying CABLE science code to a common library.
- Some CABLE science improvements which also apply to ESM1.6
- Hoping to have alpha release soon.
- CABLE development is on github.
- AM3 development on private github repo. Better than MOSRS and svn.
- Can’t wait for UKMO to transition to github. So much better than MOSRS and svn.
- Will we backport to MOSRS UM, JULES and roses repos? Feedback sought.
- Next step - Evaluation of AM3 and extendend simulation with CM3 (with JULES, MOM6 and CICE).
- Adopt new NRI built and test framework (already used for OM3)
- Ideally we want CABLE in a version or rAM3. First with UM, then with Lfric.

Q: From Matt W. Switching on chemistry?  
A : Need to check surface deposition and UKCA stuff. Can be messy w/different vegetation types. Should be a single switch in the same way.

Q : Matthew Lipson. Land working group is moving to workflows for UM ancillary generation. Are you working with Claire to align with us?  
A : Existing methods will work for high-res global, but we will need to move to other sources for high-res km-scale. We are looking at CCI now. We are using ANTS suite.

**Heidi - ACCESS-rAM3 (beta-release) and WG compute resources**

- Watch [Hive Docs](https://access-hive.org.au/models/run-a-model/) for documentation on new beta-release of ACCESS-rAM3.\*\*
- Please apply for WG resources. We didn’t use all our quarterly kSUs. If you have a good case for suite testing, please put on experiment category of atmosphere for resources you want. See [here](https://forum.access-hive.org.au/t/applying-for-atmosphere-wg-resources/844) for how to apply for Atmosphere WG Resources.

**Next WG meeting:** April dates? Let us know about any community conference/workshops to avoid clashes

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**Author:** ![pjs548](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/pjs548/32/2484_2.png) [@pjs548](https://forum.access-hive.org.au/u/pjs548)\
**Post date:** [14 May 2025 02:11 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/4 "2025-05-14T02:11:14Z")

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### Atmosphere WG Meeting 30.04.2025 minutes

19 participants on Zoom

1. **Brief update from WG co-chairs:**

- Charmaine Franklin (BoM);  
ACCESS-A and ACCESS-AE evaluation:

- BoM has a version of the ECMWF Machine Learning model, AIFS (Artificial intelligence Integrated Forecasting System) running for experimentation

- Matt Woodhouse (CSIRO):

- Yi Huang (Uni Melb):

1. **Science talk - Towards enhancing climate projections through improved understanding and simulations of marine low clouds** by _Qinggang Gao_

- There was discussion on the contributions of cloud water vs cloud ice to Top of Atmosphere fluxes. By looking at low vs middle cloud (defined via pressure levels) there didn’t seem to be much to change the conclusions – even allowing for different thresholds across models.

- Also discussion on possible use of a satellite radiance simulator although unclear if suitable model fields are accessible.

1. **Short talk - W21C plans** by _Bethan White_

- Flagship innovation of ACCESS-rAM3, using CABLE as the surface exchange model. Will be running at km-scale over a large area (Victoria, Tasmania and NSW)

- Will develop a Global N512 (possibly higher resolution) version, coupled to MOM3.

- Also considering developing a coupled regional suite

1. **ACCESS-rAM3: Beta release & future development:** _Heidi Nettelbeck_

- ACCESS-NRI supported release of ACCESS-rAM3, an implementation of the UKMO Regional Nesting Suite, is now available to the community.
- You can find more information about ACCESS-rAM3 and what you can expect to do with it in the [**Release Information**](https://url.au.m.mimecastprotect.com/s/iilmCNLwzjFZpP8N0hzCPcyWoJX?domain=forum.access-hive.org.au) on the Hive Forum.

1. **Momentum User Workshop 2025 (9-13 June):** _Charmaine Franklin_

- UKMO Momentum Workshop will include a range of topics, e.g., idealised LFRic modelling workshop, regional session focussed on RAL3-LFRic, etc.

- Rough program:

1. **AAF authentication on ACCESS-Hive Forum:** _Heidi Nettelbeck_

- AAF authentication is now the preferred way to log into theACCESS-Hive Forum.
- Please follow [**these instructions**](https://url.au.m.mimecastprotect.com/s/LIiWCP7yBls0nNR4KhmH5cxIo5k?domain=forum.access-hive.org.au) to [**add AAF authentication to your Forum account**](https://url.au.m.mimecastprotect.com/s/kQ1lCQnzDmsXLlp6kHOIAcGMRNL?domain=forum.access-hive.org.au) without affecting the way you currently log in.

1. **Compute/storage resources:** _Heidi Nettelbeck_

- We have 875 kSU allocation for Q2/2025 for experiments.
- See [**here**](https://url.au.m.mimecastprotect.com/s/WomwCROAEnsGX01rvfESpc1nWSw?domain=forum.access-hive.org.au) for how to apply for Atmosphere WG Resources.

1. **Next Atmosphere WG meeting:** _4 June, 2025 at 11:30am_

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**Author:** ![alanah.chapman](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/alanah.chapman/32/4377_2.png) [@alanah.chapman](https://forum.access-hive.org.au/u/alanah.chapman)\
**Post date:** [4 June 2025 03:38 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/6 "2025-06-04T03:38:10Z")

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**Atmosphere WG Meeting 04.06.2025 minutes**

18 participants on Zoom.

1. **Brief update for WG co-chairs:**

- Yi Huang (Uni Melb)

- Charmaine Franklin (BoM)

- Heidi Nettelbeck

1. **Supported reference datasets update** by Clare Richards

- By mid-2027 overall storage should increase by 2 PB

- ACCESS-NRI provide merit-based support for data storage and sharing, working with the community

- Framework and procedures for dataset management being developed

- Support for both curated and ‘sandboxed’ (short-term/fixed duration) datasets

- Data request processes being streamlined

- Flagged: _High priority datasets for the community should be communicated to NCI_

1. **ACCESS Workshop 2025 (8-12 September)** by Heidi Nettelbeck and Paige Martin

- Abstract submissions now open!!! Close on 15th June 2025.

- Paige on Atmosphere WG meeting Friday 12th September agenda:

1. **ACCESS-NRI 2025/6 Workplan** by Heidi Nettelbeck

2. **Reminder to setup AAF authentication on Hive**

3. **Next Atmosphere WG meeting:** _July 2025_ date TBC

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**Author:** ![Paul.Gregory](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/paul.gregory/32/2566_2.png) [@Paul.Gregory](https://forum.access-hive.org.au/u/Paul.Gregory)\
**Post date:** [23 July 2025 05:29 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/7 "2025-07-23T05:29:34Z")

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### Atmosphere WG Meeting 23.07.2025 minutes\*\*

23 participants on zoom

**1. Updates from the co-chairs:**

- Charmaine Franklin (BoM) :

- Yi Huang (Uni Melb) :

- Heidi Nettelbeck (ACCESS-NRI) :

**2. New introductions:**

- Vinod Kumer - works with BoM in Charmaine’s team. Has recently been working on sub-km scales and working with LFRic.
- Luke Burgess - PhD student at UniMelb working with Andrew Dowdy on PyroCb.

**3. Science talks.**

3.1 Charmaine - regional LFRric simulations. A BoM team presentation including Belinda, Vinod and Ian.

- RAL3-LFRic assessment. BoM is testing regional LFRic with UK Met Office over the Australian region. A quick review of LRFic/UM differences (e.g. Psyclone, finite element geometry). GungHo is the new dynamical core of LFRic.
- This project finishes in September. The aim is deliver a community research suite.
- RAL4-LFRic will be used to replace all BoM regional modelling suites (including forecasts and reanalysis)
- We are comparing RAL3-LFRic to RAL3-UM.
- There will be no RAL4-UM!
- Case study of TC Tiffany from 2022. Examination of radar reflectivity
- Diurnally forced convection (DFC) study form 2023. Some differences - LFRic generally rains less.
- TC shows similar rain totals and rate rates
- DFC case - LFRic reduced rain total by \< 50%. A smaller diurnal cycle and different rain rate distribution with fewer occurrences of \< 100 mm/hr. A reduction in light/medium rain rates in LFRic.
- Cloud cover differences. LFRic has less medium and high cloud, particularly over the ocean and along the coast.
- High cloud initially spins down in LFRic. Medium cloud spins down in LFRic after T+3.
- UM has more and stronger updrafts c/f LFRic. Largest differences occurs in upper troposphere for TC case and mid-upper troposphere for DFC.
- Looking at convective outflows and waves. LFRic often has waves at boundaries, and waves propagating ahead of convection at all heights.
- These convective outflows look to be inhibiting convection initiation, and could be another cause of rainfall differences over the ocean and coastal region as convection propogates off-shore.
- Melbourne case studies have examined fog, extreme cold and heatwaves.
- For Jan 2020 heatwave example, LFRric delayed a cool change c/f UM, resulting in large Tmax discrepancy.
- Fog case study of December 2023. LFRic has slightly more fog but overall is quite similar. Similar visibility histograms.
- Mid-latitude precip rainfall amounts are similar, LFRic produces more snow. LFRic has lower cloud amounts.
- In the winter extreme case study of June 2021, LFRic accumulated more snow, especially in the first 24 hours, but less rainfall than the UM. Higher max lightning flashes in LFRic, but larger lightning mean in the UM.
- Next steps :
  - Further case studies.
  - Verification and evaluation against observations.

- RAL3-LFRic RAS and RNS are already ported to NCI.
- Testing RAL3-LFRic for ACCESS-C/CE and A/AE domains.
- Q&A:
  - Q : Paul Gregory. Where are the differences coming from?
  - A: Ian/Charmaine. Science is unchanged. All differences come from discretisation changes (new finite element mesh) and new dynamical core (i.e the underlying numerical methods).
  - Q : Peter Stienle. LFRic seems more ‘organised’ in convection than UM. Is it an issue of small and large scale noise? Do we know which one is better yet?
  - A : Charmaine. LFRic is less diffusive which is good. But the reduction in rain rates look worse.
  - Q : Peter - peaks in high cloud seem to have been moved by a few hours?
  - A : Charmaine. How fields are initialised and ice clouds needs further examination. These factors changes the radiative fluxes which could impact cloud spin-up. Could be a technical problem, not a model problem.
  - Q : Peter - initialised from same initial conditions?
  - A : All initialised from UM. We are not yet up to nesting regional LFRic in global LFRic.

3.2 Andrew Brown - coastal wind / sea breeze climatology.

- Sea breezes can relate to convection initiation, coastal wind energy resources, and human health in urban areas
- Previous studies have used point-based observations or hi-rest numerical model data to produce climatologies
- Exploring a diagnostic which can be applied across all model data for the Australian coastline.
- We are going to process data from 2.2 to 25 km. Hi-res data requires some smoothing to remove small scale fronts and gradients that aren’t sea breezes.
- Compute three diagnostics used in previous studies.
- The diagnostics then create a mask based on a threshold to find candidates for sea breeze objects.
  - Diagnostic #1 - Sea Breeze Index (SBI) - circulation diagnostic which evaluates 3d winds over land and water.
  - #2 - Horizontal kinematic frontogenesis (F) - looking at gradients in 2d surface data.
  - #3 Hourly rates of change - analysing timeseries changes of temperature for example.

- Case study in Perth compares three indices w/AUS2200 and ERA5. The H diagnostic doesn’t show up in ERA5, the other two are similar.
- Challenge to remove spurious ‘F’ in inland convection.
- Spatial counts b/w SBI an F are similar. H tends to count objects further inland.
- Challenges in object detection remain, e.g. removing topographic flows, cold fronts.
- How to verifiy? Against what kinds of observations?
- SBI is computationally difficult as it requires model level data.
- As you resolve more in high resolution models, things get messy!
- Want to apply F to BARRA-C for more climatological analysis. Explore relationship b/w sea breezes and SSTs. Might investigate further w/ rAM3.

**4. ACCESS 2025 Workshop - Heidi Nettelbeck**

- Reminder that ACCESS 2025 workshop registration closes on Aug 15. Please register!
- Annual working group day is September 12. What do we want to discuss? What agenda items?
- Have to finalise the program over the next few days.
  - LFRic questions from Paul and Chermelle, resources/runtime, driving with different ICs
  - Suggestion from Mat Lipson re: collaborating on STASH outputs?

- Please post further suggestions to forum, preferably a new topic in the Atmosphere WG forum.

**5. ACCESS-NRI Visualisation Project - Call for EOI - Heidi Nettelbeck**

- Call for expressions of interest. We have a visualisation expert (Owen). Let us know if you want to be involved in a 3-month project. EOI closes in next week 30.07.!

**6. Compute and storage - Heidi Nettelbeck**

- We have 875 kSU until end of September. See [here](https://forum.access-hive.org.au/t/applying-for-atmosphere-wg-resources/844) for how to apply for Atmosphere WG Resources.

**7. Paul Gregory:**

- Request for any existing AUS2200 input data for a small case study.  
_EDIT : No longer required. Paul has AUS2200 up and running!_

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**Author:** ![cchambers](https://avatars.discourse-cdn.com/v4/letter/c/3ec8ea/32.png) [@cchambers](https://forum.access-hive.org.au/u/cchambers)\
**Post date:** [22 October 2025 04:07 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/8 "2025-10-22T04:07:33Z")

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**Atmosphere Working Group Meeting 22 October 2025**  
22 participants on zoom

**Charmaine Franklin - LFRIC update**

· LFRIC assessment is complete

· ACCESS-A

· next 12 months RAL4 tests.

· Met Office - RAL5 - scale aware convection scheme included. - able to deal with shallow convection at say 4 km resolution.

· Simplified aerosol scheme included.

· Orographic drag representation

· Irrigation scheme - JULES

**Matt Woodhouse CSIRO**

· with Beck Jackson RNS glomap turned on coupled to CASIM

· improvement in emissions - marine aerosol

· think about incorporating into ACCESS-rAM3.

· can’t run from reanalyses.

· contact Matt if interested in using this setup.

**Yi Huang W21C**

· 21st Century Weather update

· Global AM3 25 km successfully running, CABLE.

· Flagship - 10 km Australia region, then higher resolution sub domains.

**Heidi ACCESS-NRI**

· ACCESS-rAM3 latest release RAL 3.3 UM 13.5; anomalous rainfall spin-up in GAL9 nest fixed.

· Looking for alpha testers.

· Feedback by 10 Nov welcomed!

· 2025 ACCESS Workshop feedback - biannual workshops possible, contact Heidi with your thoughts.

· Some expressed satisfaction with current annual format; enjoyed discussions across WGs.

**Marcus Thatcher - SHEP**

- Sub-Hourly Extreme Precip (SHEP) Flagship Pilot Study.

- CORDEX

- 2-3 year pilot study.

- Aims - quantify sub hourly events over Australian cities. Projected changes.

- multi model intercomparison project, Australia/New Zealand.

- 2 main activities

- Events to inform climate analysis - few day runs. Validation runs - can events be reproduced? BARRA boundary conditions.

- Climate.

- Perturbed environments on present day extreme events.

- 3 people expressed interest in the data, amd if space is limited, then then UM data component. ACCESS-NRI need to know if others are interested in using this data.

- 21st Century Weather will be involved with SHEP

- Question about domain sizes, potential boundary effects in small domains.

- Questions about relying on particular schemes and resolutions, different setups - different results.

**Shixue Li - ACCESS-AM3**

- Progress in ACCESS-AM3 v4

- UM + CABLE

- 20 to 25 km resolution - global. N512

- mproved convective structures in tropics.

- Crashing issues. Errors in vertical motion - south pole. high res ozone issues.

- Model was not told the ozone was 2D.

- Greenland high humidity issue.

- Various issues have been overcome. bugs, ozone.

- Extreme local values at some points in ancil file

- lakes incorrect in some areas, triggering high temperatures and instability.

- Need for thorough checks to find and fix issues.

- n512 18 KSU per month. Optimization has improved efficiency of runs

- Future next stage is 5 km.

- negative soil moistures - also found in earlier setups. - could be a particular soil moisture variable that can be negative.

- Data available on scratch for those interested.

- Questions about tests to see benefits of global high res.

**Heidi - closing**

· Please continue discussion on high-res AM3 development in [this subsection](https://emoved%20anomalous%20rainfall%20spin-up%20in%20GAL9%20nest) on the ACCESS-Hive forum

· Meetings for development and evaluation of ACCESS-CM3. Please see [this Hive Forum post](https://forum.access-hive.org.au/t/planning-meeting-cm3-evaluation-through-esm-working-group/5305/4) and [slides](https://forum.access-hive.org.au/uploads/short-url/tkQi5BDmLCOAxckEiurvfP3kBBq.pptx) for more info.

· Apply for working group resources (875 KSU available for Q4). See [here](https://forum.access-hive.org.au/t/applying-for-atmosphere-wg-resources/844) for how to apply.

· Next meeting will be held in November, probably Wed 11:30am (not last week of Nov) . Announcement to follow.

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<div class="post-metadata">

**Author:** ![Claire\_Vincent](https://avatars.discourse-cdn.com/v4/letter/c/51bf81/32.png) [@Claire\_Vincent](https://forum.access-hive.org.au/u/Claire_Vincent)\
**Post date:** [19 November 2025 02:48 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/9 "2025-11-19T02:48:27Z")

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## ACCESS NRI Atmospheric Working Group Meeting minutes - 19/11/2025

21 participants on zoom

**Updates from the co-chairs**  
_Charmaine Franklin (BoM):_

- RAL4 project has started, UKMO + partners. Four parts to this project: Ancil dev; Optimisation; Workflows / git; Model development and Scientific Assessment
- CSET Convective Scale Evaluation Toolkit
  - Visualisation and diagnostics, work on including obs starting next year
  - Working with Jorge Bornemann from NZ - he is happy to talk to the WG meeting next year.

_Yi Huang (Uni Melb):_

- 21stCenturyWeather Modelling Science update. Regional coupled atoms-ocean model team has made some progress → a test domain has been setup
- Also some progress with regional atmosphere only domain. Scoping inclusion of Cable
- Global atmosphere only model progress
- Also working on urban model

_Heidi Nettelbeck (ACCESS-NRI):_

- ACCESS-NRI - collected feedback from alpha-release of RAM3. Beta-release due on a few weeks. Still open to more feedback (including on OSTIA capability)
- Progress towards an ACCESS-AM3 release

**Data update** _Kelsey Druken_

- Data storage options at ACCESS-NRI
- Introduction to Joshua Torrance, helping in data management at ACCESS-NRI
- Merit allocation: Provide storage and compute resources
- 3 Categories of data storage:
  - 
    1. Working group storage gx60 ~400TB. Most flexible storage option. Best suitable for data that’s changing and evolving. Longer term than /scratch, but not long-term storage.

  - 
    1. Data Sandbox - sharing data across the working groups & NCI platform. Flexible lightweight management, added to ACCESS-NRI’s intake catalogue. No DOIs or THREDDS - not what you need for publication

  - 
    1. Data Publication - longer-term support with persistent identifier.

- Get in touch with data.access.nri@anu.edu.au for support for a reference dataset.

**CMIP7 updates and timelines** _Rachel Law_

- DECK - core set of experiments that every model needs to submit as entry card
- Fast Tracks
- Community MIPS
  - See GMD Special Issue

- ACCESS plans for CMIP7:
  - ACCESS-ESM1.6 (update of ESM1.5). Targeting Fast-track MIP
  - ACCESS-ESM3 family - Community MIPS - Tuesday monthly meeting 10:30 (see details on the forum)

- ACCESS-ESM1.6.
  - Biggest change from ESM1.5 is CICE4 to CICE5.
  - Land - work adding Australian vegetation types
  - Atmosphere - not much change, 38 levels in the atmosphere
  - Changes around pseudo icebergs
  - Big improvements in compute, thanks to ACCESS-NRI
  - New plant functional types for Australia
  - Two types of Australian Trees - Xeric (~Acacia) and Mesic (Eucalypts) → Improved carbon fluxes

- DECK and Fast track aim to run by the end of next year
- Preference for emissions-driven with interactive carbon in CMIP7 (rather than prescribed concentration). We have capacity to do this in ESM1.6.
- Updated CMIP6 / CMIP7 solar constant → Lower solar constant led to cooling in the system, but challenges with stabilisation. Started new runs with reduction in ocean albedo → greater stability
- Carbon spinup - currently tuning ocean biogeochemistry.
- Land - currently fairly confident of zero flux (photosynthesis balances respiration).
- Equilibrium Climate Sensitivity - 3.36, a bit lower than previous 3.88 in ESM1.5.
- Next steps:
  - Finalise pre-industrial forcings
  - Test historical simulation
  - Start piControl
  - Branch spin-up for emissions-driven pre-industrial
  - Test emissions driven historical runs
  - Test workflow for model output to data publishing.

**ACCESS-AM3 release** _Martin Dix_

- Model configs:
  - ACCESS-AM3 - 21st Century Weather running at n512, new urban scheme in CABLE (Jiachen Lu).
  - ACCESS-CM3 - 100 km and 25km ocean
  - ACCESS-rAM3

- GC5 Central
- ACCESS-CM2 had a high ECS of 4.7K (IPCC best estimate range 2.5-4)
- GAL9 runs \> 6K, unacceptably high, perturbed parameter ensemble to find a result with a more reasonable ECS
- New version GC5 Central, with ECS ~4 K.
- Testing in CM3 - \> getting closer to reasonable ECS.
- Testing Cable in a version of rAM3.
- Update using Australian PFTs, CMIP7 forcing
- Building Cable as a library - \> same Cable code for all models
- Evaluation - data is now in intake catalogue for easy loading into Jupyter notebooks.
- CM3 evaluation would welcome atmosphere and land evaluations
- Is the AM3 evaluation part of this? Or does it have its separate evaluation.

_Lachlan Whyborn_:

- AM3-alpha release ready some time next week
- There will be a post on the forum where you can request access
- Anyone who is interested in testing the alpha version, please keep an eye out for the post.

**ESA CCI SST and sea-ice dataset** _Heidi Nettelbeck_

- Community interest for ACCESS-NRI to potentially support for ESA CCI SST and sea-ice dataset

**Compute and storage resources** _Heidi Nettelbeck_

- Only experiment request this quarter from Chris Chambers.
- Getting close to the end of the quarter. If you’re thinking of running something, please get it in quickly (next week or so)! → See [here](https://forum.access-hive.org.au/t/applying-for-atmosphere-wg-resources/844) for how to apply for Atmosphere WG Resources.

**Next WG meeting**

- February next year - avoid AMOS week

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<div class="post-metadata">

**Author:** ![heidi](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/heidi/32/335_2.png) [@heidi](https://forum.access-hive.org.au/u/heidi)\
**Post date:** [20 April 2026 00:56 UTC](https://forum.access-hive.org.au/t/meeting-minutes-2025-atmosphere-working-group-achived/4149/11 "2026-04-20T00:56:02Z")

</div>

2 posts were split to a new topic: [Meeting Minutes 2026: Atmosphere Working Group](https://forum.access-hive.org.au/t/meeting-minutes-2026-atmosphere-working-group/6284)