Canada’s Black Carbon Inventory Report 2025: annex 2

Submission to the United Nations Economic Commission for Europe

Canada reports on black carbon emissions to the United Nations Economic Commission for Europe (UNECE) through the European Monitoring and Evaluation Programme (EMEP) Centre on Emission Inventories and Projections (CEIP) in conjunction with the 1979 Convention on Long-range Transboundary Air Pollution (CLRTAP) and its associated protocols. Black carbon was added as a component of fine particulate matter to the amended (2012) Gothenburg Protocol 1999, which calls for PM_2.5 reductions to focus on sources that have significant black carbon content, and for Parties to voluntarily report emissions and projections of black carbon. The black carbon emissions are reported for all years from 2013 and are submitted to UNECE at the same time as Canada’s Air Pollutant Emissions Inventory.^{Footnote 1} 

A2.1 Overview of the United Nations Economic Commission for Europe Reporting Template

Canada is using the United Nations Economic Commission for Europe’s (UNECE) Annex I emissions reporting template and the associated Nomenclature for Reporting (NFR) codes for reporting its black carbon emissions internationally. The UNECE NFR categories correspond to the sectors described in the EMEP/EEA Air Pollutant Emission Inventory Guidebook 2023 (EEA, 2023). In addition to providing technical guidance for developing inventory methodologies, the 2023 EMEP/EEA guidebook includes instructions for attributing sectoral emissions to NFR codes. Whereas the Black Carbon Inventory Report groups emissions by sectors (e.g., pulp and paper industry), the emissions in the UNECE are grouped by process and combustion sources. For example, the pulp and paper industry within the Black Carbon Inventory Report includes both combustion and process emissions. The black carbon emissions are associated with the combustion component which is mapped to NFR sector 1A2d (Stationary combustion in manufacturing industries and construction: Pulp, Paper and Print). The process component is mapped to NFR sector 2H1 (Pulp and paper industry) which does not produce any black carbon emissions. Table A2–1 illustrates the structure of the UNECE reporting template. The template, last revised November 18, 2019, can be found in its entirety on the CEIP website.

Table A2–1: Excerpt from United Nations Economic Commission for Europe Nomenclature for Reporting Template for 2025

Notes:
BC = black carbon
GNFR = Gridded nomenclature for reporting
IIR = Informative Inventory Report, which is equivalent to Air Pollutant Emissions Inventory Report (APEI) and Black Carbon Report in Canada
LPS = Large point source
NMVOC = Non-methane volatile organic compounds (refer to Annex 1 of the APEI for more information)
TSP = Total suspended particles (equivalent to total particulate matter in the APEI)

A2.2 Mapping of Black Carbon Inventory Emissions to the United Nations Economic Commission for Europe’s Nomenclature for Reporting Categories

The mapping of black carbon inventory emissions to UNECE NFR categories is based on the mapping of the PM_2.5 emissions from the Air Pollutant Emissions Inventory (ECCC, 2025). As specified in section 3.1 of the present report, only the PM_2.5 emissions from combustion activities are used to estimate the black carbon emissions. In adherence to the UNECE NFR structure, most sectoral emissions from this inventory are redistributed into their combustion and process components following the 2023 EMEP/EEA guidebook.

Despite black carbon emissions stemming from combustion activities, not all black carbon emissions are necessarily mapped to combustion NFR codes under the UNECE structure. As an example, flaring emissions from the oil and gas industry are categorized under process, since they are considered fugitive emissions within the NFR categories. This distinction arises from the fact that flaring is the routine or emergency disposal of waste gas by combustion without utilization of the energy released.

In most cases, to redistribute emissions from the Black Carbon Inventory sectors to the NFR categories, ratios based on sources and pollutants are used to allocate emissions to the appropriate combustion and process NFR codes. In some instances, in-house estimation methodologies are used to produce detailed emissions by source, and emissions are assigned directly to the appropriate NFR code. A summary of Canada’s black carbon emissions allocated into the respective NFR code is available on the Government of Canada Open Data Portal.^{Footnote 2} 

A2.3 Reporting International Marine Navigation and Air Transportation Emissions

The black carbon inventory reports marine and aviation differently than NFR tables. While the overall total of emissions for these sectors are the same, the allocation into different categories is different.

The NFR table has five categories for marine: 1A3dii – National navigation (shipping), 1A4ciii – Agriculture/Forestry/Fishing: National fishing, 1A3di(i) – International maritime navigation, 1A3di(ii) – International inland waterways, and 1A5b – Other, Mobile (including military, land based and recreational boats). The Black Carbon Inventory Report includes all emissions occurring from domestic marine navigation (1A3dii), fishing vessels (1A4ciii) and military vessels (1A5b) in one category as those emissions contribute to Canada’s national total. International marine navigation (excluding fishing and military operations) is reported in a separate table in the Black Carbon Inventory Report, the Air Pollutant Emissions Inventory (ECCC, 2025) and the NFR table, as those emissions do not contribute to Canada’s national total. This is consistent with international reporting requirements. No values are reported under 1A3di(ii) – International inland waterways.

Similarly, the NFR table has five categories for aviation: 1A3ai(i) – International aviation landing/takeoffs (LTO) (civil), 1A3ai(ii) – International aviation cruise (civil), 1A3aii(i) – Domestic aviation LTO (civil), 1A3aii(ii) – Domestic aviation cruise (civil), and 1A5b – Other, Mobile (including military, land based and recreational boats). The Black Carbon Inventory Report includes all emissions occurring from civil LTO cycles—1A3ai(i) and 1A3aii(i)—and military flights (1A5b) in one category as those emissions contribute to Canada’s national total. The emissions attributed to the cruise phase for civil flights are reported separately in the black carbon inventory report and the NFR table, as those emissions do not contribute to Canada’s national total. This is consistent with international reporting requirements.

References

[ECCC] Environment and Climate Change Canada. (2025). Canada’s Air Pollutant Emissions Inventory Report 1990–2023. The Canadian Government’s Submission under the Convention on Long-Range Transboundary Air Pollution to the United Nations Economic Commission for Europe (March 2025).

[EEA] European Environment Agency. (2023). EMEP/EEA air pollutant emission inventory guidebook 2023.