Create test config for cice5 integration

[anton-seaice]

Create a demo config for cice5 work, using ACCESS-NRI/ACCESS-ESM1.6#70 build and coupling updates

[anton-seaice]

I put a start in here:

dev-preindustrial+concentrations...80-dev-preindustrial+concentrations+cice5

It needs some payu modifications to run ... I am working on those in payu-org/payu#572

[anton-seaice]

I've done some runs with this configuration now. The configuration is based on the esm1.6 configuration from about March - similar to the PI-02 configuration. The labels are as follows:

• cice5-db: cice5 with the parameters similar to @DaveBi
• pi-02: PI-02 output on gadi
• cice4 baseline to match the cice5 run from this repo
• c5+bubbly: same as the other cice5 run but with 'bubbly' conductivity instead of 'MU71'

And compared to modern day Observations (purple):

Southern hemisphere results don't look that good. I will try setting chio / sinw and cosw as suggested by @ofa001

I assume the initial conditions will not be impacting after a few years ... but should we be trying with some more realistic southern hemisphere initial conditions ?

[ofa001]

Hi @anton-seaice, Yes the 1m initial conditions in the SH could be impacting these results still, especially the first few summers, but I am surprised the winters the ice extent is also greater than normal the difference between bubbly and MU71 is minor as I suggested.

The turning angle change may be small as well, it was tunings we had in cice4 but didnt include in cice5 as we had such large warm biases in SH and initially cold biases in our Arctic spin ups and didnt see how they would help.

Are these runs easy to spot in your tm70 space.

[anton-seaice]

Here is the plot of SH volume:

Summer sea-ice vol is similar between the runs, so i don't think its the initial conditions which are having a persistent impact? Unless we are saying the melt has cooled the ocean enough to do have a persistent impact ?)

The run with bubbly is here:

/g/data/tm70/as2285/payu/esm1.6-preind+c-cice5+bubbly

[anton-seaice]

Some chats in the office agreed its possible that the initial conditions dumped so much freshwater into the ocean that its settled in quite a different state, so I will try a different initial condition.

OM2 initial conditions restarts don't run for some reason (errors in ITD redistribution, possibly related to change from BL99 to zero-layer thermodynamics). Ill try starting with 'none' initial condition, but we might need something better long term.

[ofa001]

Hi Anton, I will check in the Southern Ocean how much fresher the ocean as got but yes that's a possibility depending on how thick we made the ice, its worked when we use it as an OM2 type initial condition and in runs that Noah and Dan have done with the standalone CICE6 set up, but there is no active ocean to get fresh in that situations.

…

________________________________ From: Anton Steketee ***@***.***> Sent: Wednesday, 16 April 2025 11:51 AM To: ACCESS-NRI/access-esm1.6-configs ***@***.***> Cc: O'Farrell, Siobhan (Environment, Aspendale) ***@***.***>; Mention ***@***.***> Subject: Re: [ACCESS-NRI/access-esm1.6-configs] Create test config for cice5 integration (Issue #80) Some chats in the office agreed its possible that the initial conditions dumped so much freshwater into the ocean that its settled in quite a different state, so I will try a different initial condition. OM2 initial conditions don't run for some reason (errors in ITD redistribution, possibly related to change from BL99 to zero-layer thermodynamics). Ill try starting with 'none' initial condition, but we might need something better long term. — Reply to this email directly, view it on GitHub<#80 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ADNNDARTUY6NIX755BVMGVL2ZWZQVAVCNFSM6AAAAAB2FWLH4OVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMBXHE3TQNJRGM>. You are receiving this because you were mentioned.Message ID: ***@***.***> [https://avatars.githubusercontent.com/u/79179784?s=20&v=4]anton-seaice left a comment (ACCESS-NRI/access-esm1.6-configs#80)<#80 (comment)> Some chats in the office agreed its possible that the initial conditions dumped so much freshwater into the ocean that its settled in quite a different state, so I will try a different initial condition. OM2 initial conditions don't run for some reason (errors in ITD redistribution, possibly related to change from BL99 to zero-layer thermodynamics). Ill try starting with 'none' initial condition, but we might need something better long term. — Reply to this email directly, view it on GitHub<#80 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ADNNDARTUY6NIX755BVMGVL2ZWZQVAVCNFSM6AAAAAB2FWLH4OVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMBXHE3TQNJRGM>. You are receiving this because you were mentioned.Message ID: ***@***.***>

[anton-seaice]

I will check in the Southern Ocean how much fresher the ocean as got

Oh good - thanks. This will be interesting. We might not have enough ocean diagnostics turned on ...

its worked when we use it as an OM2 type initial condition and in runs that Noah and Dan have done with the standalone CICE6 set up, but there is no active ocean to get fresh in that situations.

sorry i wasn't very clear. I tried to start cice5 using a restart from the end of an access-om2 ryf run but leaving everything else unchanged. It loaded the restart but quickly crashed. I'm trying with no sea-ice to start but needs a few hours to run yet :)

[ofa001]

Hi Anton, It wont run off the om2 restarts, Dave tried quite a few times there is a mismatch between the multilayer ice set up and the zero layer set up for the ice due to it having more internal ice layers in the stored data in the restart file. One option is to have less thick ice in the Antarctic, we used 1m not the standard 3m that's use in 'cice official release' in our runs, that might help. the 3m in the Arctic is settling into a reasonable seasonal cycle of thickness in the central Arctic, for a pre-industrial run, I little more than we have now. If we use 1m for the Antarctic, that will make for less freshening of the Southern Ocean, the overall ice left in Feb is a positive though, we normally have too little, we just need to get it 'correct amount' and then see how much ice is created each winter. Cheers Siobhan

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________________________________ From: Anton Steketee ***@***.***> Sent: Wednesday, 16 April 2025 1:01 PM To: ACCESS-NRI/access-esm1.6-configs ***@***.***> Cc: O'Farrell, Siobhan (Environment, Aspendale) ***@***.***>; Mention ***@***.***> Subject: Re: [ACCESS-NRI/access-esm1.6-configs] Create test config for cice5 integration (Issue #80) I will check in the Southern Ocean how much fresher the ocean as got Oh good - thanks. This will be interesting. We might not have enough ocean diagnostics turned on ... its worked when we use it as an OM2 type initial condition and in runs that Noah and Dan have done with the standalone CICE6 set up, but there is no active ocean to get fresh in that situations. sorry i wasn't very clear. I tried to start cice5 using a restart from the end of an access-om2 ryf run but leaving everything else unchanged. It loaded the restart but quickly crashed. I'm trying with no sea-ice to start but needs a few hours to run yet :) — Reply to this email directly, view it on GitHub<#80 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ADNNDARSVFTNBLSYBJOFHOD2ZXBZXAVCNFSM6AAAAAB2FWLH4OVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMBYGEYDENBRHE>. You are receiving this because you were mentioned.Message ID: ***@***.***> [https://avatars.githubusercontent.com/u/79179784?s=20&v=4]anton-seaice left a comment (ACCESS-NRI/access-esm1.6-configs#80)<#80 (comment)> I will check in the Southern Ocean how much fresher the ocean as got Oh good - thanks. This will be interesting. We might not have enough ocean diagnostics turned on ... its worked when we use it as an OM2 type initial condition and in runs that Noah and Dan have done with the standalone CICE6 set up, but there is no active ocean to get fresh in that situations. sorry i wasn't very clear. I tried to start cice5 using a restart from the end of an access-om2 ryf run but leaving everything else unchanged. It loaded the restart but quickly crashed. I'm trying with no sea-ice to start but needs a few hours to run yet :) — Reply to this email directly, view it on GitHub<#80 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ADNNDARSVFTNBLSYBJOFHOD2ZXBZXAVCNFSM6AAAAAB2FWLH4OVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMBYGEYDENBRHE>. You are receiving this because you were mentioned.Message ID: ***@***.***>

[ofa001]

Hi @anton-seaice, The data was there in the ocean files, there is major melt of the 3m ice in the Southern Ocean in the first couple of months, then slower as the autumn/winter seasons occur so just at the ice edge as normal.

There is strong salinity signal in the surface 50m which gradually mixes down. If the initial condition was only 1m thick then we would only get 1/3 of the response and it would be less drastic, and we should get a better result I guess we used that back in cice4 (access-om, access 1-0/3) initialization period.

I will check the last year of that run to see how far the surface salinity signal has mixed, it will be through the main gyres, which is why the ice has travelled further north than usual.

[ofa001]

Hi @anton-seaice just looked at year 10 of the run, the initial condition is still having an impact as even in the summer months the two gyres (Ross and Weddell for the non Oceanographers who are following) but particularly the Weddell are pulling the excess sea ice north its melting and cooling the waters and lowering the potential freezing point for the next winter, hence the signal is lasting and decaying as fast I would have expected, a 1m initial condidtion or none might work as an option. I will check how much ice was left in Dave's "none: initialized SH run by Dec31 and what the salinities were like in comparison to this run.

[ofa001]

Hi @anton-seaice just looked at the end of year1 of Dave's "none' initialization run, there is still ice present in the SH. the salinity in the ocean freshens during the year but not as severely as in the 3m case so its worth trying as an option alongside 1m whilst keeping 3m for the Arctic as that is closer to the result we are aiming for there.
Also was just discussing with Dan his latest SH fast ice runs, he is initializing with the "no ice" condition which make sense for his case.

[anton-seaice]

Volume looks much the same starting from no ice condition compared to 'default':

Although areas look good (and possibly better) in the last 5 years of my not very long run:

My feeling is to run that a bit longer as see what happens ?

I didn't have any success yet with starting with ~1m thick initial condition.

Config ran is here:

dev-preindustrial+concentrations...80-dev-preindustrial+concentrations+cice5

results are in the poorly named /g/data/tm70/as2285/payu/esm1.6-preind+c-cice5+om2_ic

[DaveBi]

Hi @ofa001 @anton-seaice, obviously I made a realy poor mistake with the experiment setting -- forgot to switch "runtype" to "continue" after the first job ("initial") and thus the following years are all invalid. Thanks a lot for spotting this error. I've now tested the "continue" run but see the model crash because of " ice: Vertical thermo error" (again). This should not happen if the cice restart file is properly written and read in, and the restart fields are in right place the "continue" job. I wonder, Anton, if you have made any change to the relevant code for your sucessful tests...