Update scenario names according to latest naming in ScenarioMIP paper

[laurinks]

In light of the new names for the six scenarios (see ScenarioMIP paper https://egusphere.copernicus.org/preprints/2025/egusphere-2024-3765/), I suggest to update the scenario names.

In the December 2024 submission, this had let to confusion as different teams had different interpretations of the correspondence between the new names (Very Low after High Overshoot, Very Low with Limited Overshoot) and the old names (Very Low, Low Overshoot).

Moreover, I suggest to remove the old scenario name Medium Overshoot.

@danielhuppmann, @phackstock : Does that make sense to you? Or does it create problems with the existing uploads to the IIASA database? Thanks!

[danielhuppmann]

Thanks for the suggestion @laurinks - no objections from my side, but did you discuss this with all teams? And what to do about the already-submitted scenarios?

If teams will resubmit all scenarios anyway, we can simply set the existing scenarios to non-default, so they will not be immediately visible in the Scenario Explorer.

[laurinks]

but did you discuss this with all teams?

No. For me, it seems to be a no-brainer to use the correct scenario names. For the December '24 submission, we had a Google spreadsheet with all teams to clarify the correspondence between old and new names for the individual submissions. And this could be avoided, I think, by using the correct names.

And what to do about the already-submitted scenarios? If teams will resubmit all scenarios anyway, we can simply set the existing scenarios to non-default, so they will not be immediately visible in the Scenario Explorer.

This is a good question that I have no experience with. Your suggestion sounds good to me. And from my understanding of the process, I expect that all teams will (re-)submit all their scenarios for the April '25 submission. Of course, it would be great to get confirmation from the teams on this. Do you have an overview of team members that are taking care of the upload to the IIASA database and could be tagged here?

[danielhuppmann]

I think the easiest way would be to send an email to all people on the Google-docs list, notifying that we will implement this change unless anyone objects until Friday this week. I can go ahead and send out this email, ok?

[laurinks]

Perfect, thanks!

[lolow]

+1
I would also suggest using acronyms instead of the longer names:

• The new names are longer and start similarly, making them difficult to differentiate.
• The acronyms are used in the paper and are clearly defined.

[VassilisDaioglou]

Agree with the need to use the correct naming convention and also agree on using the acronyms. Please also ensure that the possibility for variants is retained.

[flohump]

+1 for acronyms

[laurinks]

@VassilisDaioglou: Absolutely! The logic is to define the three dimensions - ssp, emissions scenario, options - and then all combinations can be submitted: https://github.com/iiasa/ssp-submission-workflow/tree/main/definitions/scenario

[lolow]

• H:
  description: "High Emissions"
• M:
  description: "Medium Emissions"
• ML:
  description: "Medium-Low Emissions"
• VLLO:
  description: "Very Low with Limited Overshoot"
• VLHO:
  description: "Very Low after High Overshoot"

[claudiatebaldi]

Is it necessary to go through all this now, when the paper is still in review? There may still be a chance that the names will change on the basis of reviewers' comments.

[laurinks]

From my perspective, the proposal is a simple update to the current scenario names, and I did not see problems with this, but just the potential to avoid confusions in the multi-model analysis process.
In case the overall decision would be to delay the correction of names, we should at least make sure that all teams submit with the same understanding, i.e. to submit the VLLO under the name "Very Low" and the VLHO under the name "Low Overshoot".

[VassilisDaioglou]

I agree with Laurin. I think it is important to ensure we use the names based on how the teams are currently approaching the scenarios - and our common understanding of the scenarios. We are currently using a different sets of names in our communications and on the scenario explorer - and we are hoping everybody is submitting consistently. This is not sustainable or even functional.

If the scenarios are renamed or even re-imagined based on the review, so be it. That will have to lead to a different common understanding across the teams, and a renaming of this template. We cross that bridge when we get there.

[jkikstra]

Also from my side supporting the change to the acronyms. It's a bit of work (potentially twice if naming changes again), both for those submitting and those with postprocessing scripts, but I don't expect it to be a lot of work. But if it avoids a miscommunication/misinterpretation (a team accidentally submitting under a different assumption from others) it's worth it.

[laurinks]

I just added the High-Low scenario to the list. Once the marker selection decisions are taken and we are phasing the June 30 submission, I would suggest that we implement this update of scenario names.

[laurinks]

On the one hand, changing scenario names right now might create unnecessary complications in scripts to prepare submissions or analyze snapshots from the DB (which had also been the argument against adapting it earlier). On the other hand, I suppose that we want to have the correct names for the final dataset that will be processed for hand-over to the ESMs and eventually made public.

@danielhuppmann : If we do not update names now, is it easy to do this ex-post in the DB? What is your recommendation on merging this PR?