[DATA REQUEST] Add global ocean reanalysis – BRAN2020

[Thomas-Moore-Creative]

Description of the data product

The Bluelink ReANalysis (BRAN) provides a 3D record of the global ocean. BRAN2020 incorporates substantial updates on the previous version (BRAN2016), including a new two-step multiscale data assimilation process. It also utilises new data products with ocean observations from recent decades.

Data here are from a Bluelink ReANalysis (BRAN) experiment, simulating 1993 to 2019, with a near-global, 10-km resolution (eddy-resolving) ocean model. Data assimilation adjusts the ocean state to observations of temperature, salinity, and surface height. Model output is a realistic reconstruction of mesoscale upper ocean dynamics around Australia for this period.

Ocean reanalyses have various applications, such as, investigation of the ocean directly (e.g. general circulation, extreme events) or supporting further research (e.g. particle tracking, regional model boundary conditions)

For a more complete description and assessment of BRAN2020, including the observations assimilated, please refer to: Chamberlain et al. 2021. Next generation of Bluelink ocean reanalysis with multiscale data assimilation: BRAN2020. Earth Syst. Sci. Data, 13, 5663–5688, https://doi.org/10.5194/essd-13-5663-2021

Location of the data product on Gadi

/g/data/gb6/BRAN/BRAN2020

Checklist

• [x] This data product is stable (unlikely to change substantially or move)
• [x] This data product is of use to the broader community
• [x] This data product is documented: https://geonetwork.nci.org.au/geonetwork/srv/eng/catalog.search#/metadata/f9372_7752_2015_3718
• [x] This data product is licensed under: Creative Commons Attribution 4.0 International - The data is freely available to the public through NCI.
• [x] Those who want to access this data can be added to the project that houses it - https://my.nci.org.au/mancini/project/gb6/join

[dougiesquire]

Thanks for your issue @Thomas-Moore-Creative!

This should be pretty easy to add. However, your request has made me consider the scope of this Intake catalog. Should it include everything that fits within the schema? Should it only include climate model data (which is currently the case)? Should we have multiple catalogs for different types of data: e.g. one for reanalyses, one for climate model runs? I don't know and I think I need to have a chat with some folks at ACCESS-NRI and get back shortly sorry.

[Thomas-Moore-Creative]

Fully understand the need to be thoughtful and consider how to scope the catalog.

One might argue that one common step in beginning to evaluate a model would be comparison to a reanalysis? Might be handy to have BRAN2020 there for discovery one way or another?

Thanks for the consideration and for making these data discovery tools available.

[charles-turner-1]

@rbeucher Should we consider adding this in addition to the other data requests we've been working on?

[rbeucher]

Yes. let's do that.

[Thomas-Moore-Creative]

FYI - I built my own catalog for BRAN2020 for a project last year ( which may / may not be up to date with recent BRAN2020 additions )

You might wish to approach this from scratch but the details for my personal catalog are here in case they are useful?

• BRAN2020-intake-catalog
• use ecgtools to build a custom intake-esm catalogue for BRAN2020

The ecgtools parser and builder object might / might not be up to your standards?

I have a demo notebook here with an example - BRAN2020 (1993 - 2022) - compute climatology of ocean currents in 8 lines of code with less than a minute of NCI ARE walltime on a cluster costing 20 cents per hour.

• https://github.com/Thomas-Moore-Creative/BRAN2020-intake-catalog/blob/main/notebooks/BRAN2020-catalog-demo.ipynb

Thanks for the efforts on this.

[rbeucher]

Thanks @Thomas-Moore-Creative. I have requested access to the project. I don't know if there is an intake-esm catalog already available there. If not we will get in touch with NCI and add one.

[rbeucher]

I just had a look. There is no catalog in /g/data/gb6/catalog/yml

[rbeucher]

gb6 is an NCI data collection so we can't write to it directly. We can ask NCI to add the catalog using your code @Thomas-Moore-Creative.

[charles-turner-1]

I've requested to join the group. @rbeucher did you want me to ping NCI?

[rbeucher]

I have just put a request through the NCI Help Desk. I have shared the ticket with you.

[Thomas-Moore-Creative]

I just had a look. There is no catalog in /g/data/gb6/catalog/yml

Thanks for having a look. As hopefully documented in my repo this code built a personal catalog that was stored and used locally.

[rbeucher]

I'll send them the link to your code @Thomas-Moore-Creative if that is OK with you.

[Thomas-Moore-Creative]

I'll send them the link to your code @Thomas-Moore-Creative if that is OK with you.

It's public, but also over a year old and JGE ("just good enough") for my purposes at the time. It's not a shining example of software engineering but would help someone starting from zero.