Adding biomass subcategories for energy-related emissions

[danielhuppmann]

This PR adds biomass-specific subcategories for emissions from energy demand (use). It's similar to #347 but implements a tag-list to be extendable easily later on, per discussion with @volker-krey.

I assume that we are only interested in fuel-source-specific detail (biomass, later maybe biofuels) but not the type of fuel (solids, liquids, gases) so I have omitted this intermediate aggregation. Per the comment by @VassilisDaioglou at #347 (comment), I have added modern vs. traditional biomass subcategories.

I also believe that this sub-division does not make sense for Industrial Process emissions, so I have omitted it.

[volker-krey]

From the perspective of the emissions variable tree this looks excellent to me. However, the current proposal only includes emission from biomass combustion on the energy demand side with supply side emissions missing. Adding equivalent supply side variables, including electricity and heat generation, hydrogen, liquid, gaseous, and solid fuel production would be important to have a complete set of variables. In addition, also having aggregate supply and demand side variables and a total energy variable would be useful (e.g., Emissions|XXX|Energy|Supply|Biomass, Emissions|XXX|Energy|Demand|Biomass, Emissions|XXX|Energy|Biomass).

[jkikstra]

For this discussion we should include Steve Smith (@ssmithClimate) as we're here trying to match what CEDS is doing.

My understanding is that in principle, we should indeed do "all" sectors.

Adding equivalent supply side variables

Thus, @volker-krey is right here.

I had a look at VOC emissions in CEDS, to understand where (global) emissions are (not) virtually zero:

With the mapping to Harmonization sector variables:

Harmonization Sectors	59_Sectors_2024
Energy Sector	1A1a_Electricity-public
Energy Sector	1A1a_Electricity-autoproducer
Energy Sector	1A1a_Heat-production
Energy Sector	1A1bc_Other-transformation
Industrial Sector	1A2a_Ind-Comb-Iron-steel
Industrial Sector	1A2b_Ind-Comb-Non-ferrous-metals
Industrial Sector	1A2c_Ind-Comb-Chemicals
Industrial Sector	1A2d_Ind-Comb-Pulp-paper
Industrial Sector	1A2e_Ind-Comb-Food-tobacco
Industrial Sector	1A2f_Ind-Comb-Non-metalic-minerals
Industrial Sector	1A2g_Ind-Comb-Construction
Industrial Sector	1A2g_Ind-Comb-transpequip
Industrial Sector	1A2g_Ind-Comb-machinery
Industrial Sector	1A2g_Ind-Comb-mining-quarying
Industrial Sector	1A2g_Ind-Comb-wood-products
Industrial Sector	1A2g_Ind-Comb-textile-leather
Industrial Sector	1A2g_Ind-Comb-other
Aircraft	1A3ai_International-aviation
Aircraft	1A3aii_Domestic-aviation
Transportation Sector	1A3b_Road
Transportation Sector	1A3c_Rail
International Shipping	1A3di_International-shipping
International Shipping	1A3di_Oil_Tanker_Loading
Transportation Sector	1A3dii_Domestic-navigation
Transportation Sector	1A3eii_Other-transp
Residential Commercial Other	1A4a_Commercial-institutional
Residential Commercial Other	1A4b_Residential
Residential Commercial Other	1A4c_Agriculture-forestry-fishing
Industrial Sector	1A5_Other-unspecified

Where the missing IAMC variables concerned are:

• "Energy Sector" = "Energy|Supply"
• "Industrial Sector" = "Energy|Demand|Industry" + "Energy|Demand|Other Sector" + "Industrial Processes" + "Other"

(transportation is zero, so not needed)

---

including electricity and heat generation, hydrogen, liquid, gaseous, and solid fuel production would be important to have a complete set of variables

I suppose this is true, but for ScenarioMIP we don't need this - and my preference is to not create confusion with the modelling teams right now by (seeming to be) asking them for all of these variables, as we don't need all fuels for now.

[danielhuppmann]

Not sure why Biomass energy use would be relevant in "Industrial Processes", see #358

[danielhuppmann]

Now added biomass-emissions subcategories for the following:

• Energy Supply
• Energy|Demand|Industry
• Energy|Demand|Residential and Commercial and AFOFI
• Energy|Demand|Residential and Commercial
• Energy|Demand|Residential
• Energy|Demand|Commercial
• Energy|Demand|AFOFI
• Energy|Demand|Other Sector

As stated above, I don't see why "Industrial Processes" is relevant for Biomass and I assume that this is just an issue from the incorrect mapping to IPCC categories in the description.

[jkikstra]

Looks good to me.
Indeed, Industrial Processes should probably not matter.
Although I am not sure that all previous work has followed this distinction, we probably can go ahead - as this can be resolved with harmonization procedures.