Add restart description and instructions for changing date

[blimlim]

1. Summary:

What has changed?
This PR adds a description of the ESM1.6 restart files and instructions for changing their date to the documentation.

Why was this done?
Changing the restart date is common process when setting up custom experiments, and hence it would be useful to have in the config docs. I thought that it would be worth including an explanation of what the different restart files are.

2. Issues Addressed:

• Change date in restart instructions for the documentation #296

3. Dependencies (e.g. on payu, or model)

This change requires changes to (note pull request(s) where relevant):

• workflow manager (payu):
• model deployment (ACCESS-ESM1.6):
• model component or library dependency:
• input workflow:

4. Ad-hoc Testing

What ad-hoc testing was done? How are you convinced this change is correct (plots are good)?
N/A

5. CI Testing

• !test repro has been run

N/A

6. Reproducibility
N/A

Is this reproducible with the previous commit? (If not, why not?)

• Yes
• No - !test repro commit has been run.

8. Manifests

Have you changed the executable, the input files and/or the restart files?

• Yes
• No

If yes, have you updated the manifests?

• Yes
• No

To update the manifests, run payu setup (in a cloned copy of your feature branch) with reproducibility tests turned off:

manifest:
  reproduce:
    exe: false
    input: false
    restart: false
runlog:
  enable: false

Then commit the newly created manifest files (under manifests/) only to the branch for this PR.

7. Documentation

Is the documentation updated?

• Yes
• N/A

9. Merge Strategy

• Merge commit
• Rebase and merge
• Squash

[ccarouge]

Small suggestions

[anton-seaice]

Thanks Spencer - looks good

[blimlim]

@ccarouge @anton-seaice, do you think placing the restarts.md page under inputs makes sense? I wasn't too sure but it seemed like the most appropriate place

[ccarouge]

do you think placing the restarts.md page under inputs makes sense? I wasn't too sure but it seemed like the most appropriate place

@blimlim , it makes perfect sense for me. It's an input the model needs to define its initial state.

[blimlim]

@anton-seaice @ccarouge, just remembered this one! Did you have any other suggestions?

[anton-seaice]

Happy to approve - payu 1.2.1 is imminent if we want to wait ?

[ccarouge]

It looks good. I have two small comments for you or Anton about the sea-ice restart but nothing that needs a re-review from me.

[ccarouge]

and I forgot to say, I've committed a change to mkdocs.yaml to bring in proper icons for the admonition boxes.

[blimlim]

Happy to approve - payu 1.2.1 is imminent if we want to wait ?

Payu 1.2.1 is out and so I've removed the text about the cice_in.nml file

[anton-seaice]

Thanks @blimlim