nocc2020 switch added

[emolinab]

🐦 Purpose of this PR 🐦

• A new option for the cc/nocc scenarios switch was added. Specifically, nocc2020 uses historical/variable values in parameters affected by climate change up to 2020. After 2020, values stay constant for the rest of the run's time horizon.

🔧 Checklist for PR creator 🔧

• Labeling pull request correctly from the label list.

• Low risk : Simple bugfixes (missing files, updated documentation, typos) or Start/output scripts
• Medium risk : New realization / Changes to existing realization / Other changes which don't modify default.cfg
• High risk : New input files (if cfg$input is changed in default.cfg) / Modification to core model (eg. changes in equations, calculations, introduction of new sets etc.) / Other changes in default.cfg

• Providing additional information based on PR label
  Minor changes in scenario_config.csv, default.cgf, and several realizations.

• Low risk : No new model run needed.
• Medium risk : Default run based on the current version of the fork from which PR is made
• High risk
  • Default run from the current develop branch
  • Default run based on the current version of the fork from which PR is made

• 📉 Performance loss/gain from current default behavior 📈
  • Current develop branch default: 30 mins
  • This PR's default: 29.3 mins

• Added changes to CHANGELOG.md
• Compilation check (model starts without compilation errors - use gams main.gms action=c in model folder for testing).
• No hard coded numbers and cluster/country/region names.
• The new code doesn't contain declared but unused parameters or variables.
• Where relevant, In-code comments added including documentation comments.
• Made sure that documentation created with goxygen is okay (use goxygen::goxygen() for testing).
• [Not needed] Changes to magpie4 R library for post processing of model output (ideally backward compatible).
• Self-review of my own code.
• [Not needed] For high risk runs: validation of major model indicators - Land-use, emissions, food prices, Tau. %Delete this line in case it is not a high risk run%

⚠️ Additional notes or warnings ⚠️

NA

🚨 Checklist for RSE reviewer 🚨 -- @tscheypidi

• PR is labeled correctly.
• CHANGELOG is updated correctly
• No hard coded numbers and cluster/country/region names.
• No unnecessary increase in module interfaces
• All required updates in interfaces (if any) have been properly adressed in the module contracts
• In-code comments and documentation comments are satisfactory.
• model behavior/performance is satisfactory.
• Requested changes (if any) were applied correctly

🚨 Checklist for MAgPIE reviewer 🚨 -- @abhimishr

• PR is labeled correctly.
• CHANGELOG is updated correctly
• No hard coded numbers and cluster/country/region names.
• Changes to the model are scientifically sound
• In-code comments and documentation comments are satisfactory.
• model behavior/performance is satisfactory.
• Requested changes (if any) were applied correctly

[tscheypidi]

Please check whether the solution via dollar condition as suggested would work too.

[tscheypidi]

I believe this set is not needed and a dollar condition could be used instead.

[tscheypidi]

I believe a dollar condition should be a solution here setting the values as wanted. Haven't tested the suggestion below but something like that should be it:

Suggested change

	$if "%c14_yields_scenario%" == "nocc2020" f14_yields(t_nocc2020,j,kve,w) = f14_yields("y2020",j,kve,w);
	$if "%c14_yields_scenario%" == "nocc2020" f14_yields(t_all,j,kve,w)$(ord(t_all) > ord("y2020")) = f14_yields("y2020",j,kve,w);

[emolinab]

Perfect, I'll work in the dollar sign approach.

[tscheypidi]

is it now low or medium risk? It can't be both as suggested by the labels

[tscheypidi]

looks good!

[abhimishr]

Seems fine in general. I propose the following change to make it more consistent :

1. Florian introduced a scalar sm_fix_ssp2 to keep our historical behavior consistent, maybe you can use the same switch here? By replacing your hard-coded 2020 instances with sm_fix_SSP2. It helps in two ways:

• Everytime we update sm_fix_SSP2 the same is reflected in in you "holding constant after xx year" philosophy
• Avoids hard-coding a number in $ checks

2. Additionally, you can rename nocc2020 to histcc instead

[abhimishr]

good to go 🚀