Greenhouse Gas Emissions

Table of contents

The G-Cubed models that include all greenhouse gases (GHG) emissions specifically cover:

  • Carbon dioxide (CO2)
  • Methane (CH4)
  • Nitrous oxide (N2O)
  • Flurocarbons
    • C2F6 (Hexafluoroethane)
    • C3F8 (Octafluoropropane)
    • C4F10 (Decafluorobutane)
    • C5F12 (Dodecafluoropentane)
    • C6F14 (Tetradecafluorohexane)
    • CC4F8 (Cyclooctafluorobutane)
    • CF4 (Tetrafluoromethane)
    • HCFC141b (1,1-Dichloro-1-fluoroethane)
    • HCFC142b (1-Chloro-1,1-difluoroethane)
    • HFC125 (Pentafluoroethane)
    • HFC134 (1,1,2,2-Tetrafluoroethane)
    • HFC134a (1,1,1,2-Tetrafluoroethane)
    • HFC143 (1,1,2-Trifluoroethane)
    • HFC143a (1,1,1-Trifluoroethane)
    • HFC152a (1,1-Difluoroethane)
    • HFC227ea (1,1,1,2,3,3,3-Heptafluoropropane)
    • HFC23 (Trifluoromethane)
    • HFC236fa (1,1,1,3,3,3-Hexafluoropropane)
    • HFC245fa (1,1,1,3,3-Pentafluoropropane)
    • HFC32 (Difluoromethane)
    • HFC365mfc (1,1,1,3,3-Pentafluorobutane)
    • HFC41 (Fluoromethane)
    • HFC4310mee (1,1,1,2,3,3,3-Heptafluoropropane)
    • Nitrogen trifluoride (NF3)
    • Sulfur hexafluoride (SF6)

This coverage matches that of the GTAP database.

All emissions are measured in CO2-equivalent terms, converted using the IPCC AR6 conversion factors.

Gas IPCC AR 6 conversion factors
co2 1
ch4 27.9
n2o 273
c2f6 12400
c3f8 9290
c4f10 10000
c5f12 9220
c6f14 8620
cc4f8 10200
cf4 7380
hcfc141b 860
hcfc142b 2300
hfc125 3740
hfc134 1260
hfc134a 1530
hfc143 364
hfc143a 5810
hfc152a 164
hfc227ea 3600
hfc23 14600
hfc236fa 8690
hfc245fa 787
hfc32 771
hfc365mfc 914
hfc41 135
hfc4310mee 1600
nf3 17400
sf6 24300

All of the flurocarbon gases are aggregated in G-Cubed into a single collection of gases referred to as flurocarbons. Thus, G-Cubed includes the following four gases:

  • Carbon dioxide (CO2)
  • Methane (CH4)
  • Nitrous oxide (N2O)
  • Flurocarbons

Emissions attribution

Emissions can be associated with:

  • household final demand;
  • government final demand;
  • labor usage in production;
  • capital usage in production;
  • usage of other G-Cubed goods in production; and
  • production output.

This granularity of attribution corresponds to the data that is ostensibly available in the GTAP database. Note, however, that the existing GTAP data on emissions implies zero emissions resulting from government final demand and the use of both labor and capital in production.

For each cause of emissions, the emissions intensity is calculated for each of the four gases by scaling measured emissions due to that cause by the value of the cause, whether that be the value of a production input or something consumed by a household or government.

Emission intensity parameters

The emissions intensity parameters are introduced into the model as a set of CSV files in the data folder that all share the same suffix. That suffix is typically _emission_intensity_parameters.csv. There is one such CSV file for each cause of emissions. Thus, typical data folders will contain the following files:

  • household_emission_intensity_parameters.csv - for emissions caused by household consumption
  • sector_intput_emission_intensity_parameters.csv - for emissions caused by sectoral usage of the outputs from other sectors
  • sector_output_emission_intensity_parameters.csv - for emissions caused by the direct output of each sector

The following intensity values are also included but, based on current GTAP data, all intensities are zero.

  • government_emission_intensity_parameters.csv - for emissions caused by government consumption
  • sector_labor_emission_intensity_parameters.csv - for emissions caused by the use of labor in production
  • sector_capital_emission_intensity_parameters.csv - for emissions caused by the use of capital in production

These matrices are all structured as a two dimensional matrix of intensity values. The units for the values are millions of metric tonnes of CO2 equivalent gases per USD billion.

The matrix dimensions are documented below:

Household and government emission intensities

Rows are indexed by gas code and then good code.

Columns are indexed by region code.

Sector input emission intensities

Rows are indexed by gas code and then good code (the input to production) and then the sector code.

Columns are indexed by region code.

Sector output emission intensities

Rows are indexed by gas code and then sector code.

Columns are indexed by region code.

Sector labor and sector capital emission intensities

Rows are indexed by gas code and then sector code.

Columns are indexed by region code.

References

Aguiar, A., Chepeliev, M., Corong, E., McDougall, R., & van der Mensbrugghe, D. (2019). The GTAP Data Base: Version 10. Journal of Global Economic Analysis, 4(1), 1-27.