Canada’s Black Carbon Inventory Report 2024: chapter 1

Introduction

Black carbon is a short-lived small aerosol, or airborne particle, emitted by natural processes and human activities such as the incomplete combustion processes of fossil fuels, biofuels, and biomass. Black carbon has a lifetime of only a few days to a few weeks after its release in the atmosphere. Black carbon emissions have become a focus of attention due to their effects on the near-term warming of the atmosphere and on human health. Reducing black carbon emissions is of particular interest in polar regions, such as the Arctic, which are especially sensitive to the effects of black carbon. When suspended in air, black carbon turns solar radiation into heat, consequently contributing to air warming, regional cloud formation, and precipitation patterns. When black carbon particles settle on snow and ice, they darken the surface, reducing their albedo and enhancing absorption of solar radiation, thus indirectly increasing the rate of melting (U.S. EPA, 2011). Black carbon is not emitted on its own, but as a component of particulate matter less than or equal to 2.5 microns in diameter (PM_2.5), along with other components, such as organic carbon and inorganic compounds, such as sulphates.

The Arctic Council was one of the first fora to recognize the importance of taking action to address short-lived climate forcers and pollutants, such as black carbon, methane, and ground-level ozone. During Canada’s term as Chair of the Arctic Council, from 2013 to 2015, the Council first promoted actions to achieve enhanced reductions of black carbon and methane emissions. The Framework for Action on Enhanced Black Carbon and Methane Emissions Reductions was agreed to in April 2015. A key component of this action is the voluntary reporting by Arctic states of their black carbon emissions to the United Nations Economic Commission for Europe (UNECE) in accordance with guidelines from the Convention on Long-Range Transboundary Air Pollution (CLRTAP). At the Arctic Council ministerial meeting in 2017, Canada, along with other Arctic states, renewed its commitment to take action to reduce black carbon emissions. The Arctic Council states also committed to the aspirational goal of reducing collective black carbon emissions by 25% to 33% relative to 2013 levels by 2025. In line with this commitment, on November 28, 2017, Canada ratified the Gothenburg Protocol and its 2012 amendments under the CLRTAP. The amendments to the Gothenburg Protocol, which came into force in October 2019, included commitments to reduce emissions of PM_2.5 by 25% from 2005 levels by 2020 and beyond, and, in doing so, to prioritize sources of PM that are also significant sources of black carbon to provide benefits for human health and the environment and to help mitigation of near-term climate change. Canada’s black carbon emissions annual inventory allows Canada to assess its progress in reducing black carbon emissions and combatting related climate change and human health issues and to contribute towards the Arctic Council’s collective aspirational goal. Canada continues to improve the quality and transparency of information related to black carbon emissions and will continue to publish an annual black carbon inventory.

Canada’s Black Carbon Inventory Report is an inventory of black carbon emissions at the national, provincial, and territorial levels. The report is prepared and published by Environment and Climate Change Canada (ECCC) and is compiled from many different data sources. It contributes to the tracking and quantifying of black carbon emissions. This document describes the 2024 edition of Canada’s annual inventory of anthropogenic black carbon emissions, covering the years from 2013 to 2022. All emissions reported in this inventory are from anthropogenic (human) sources. Natural sources of black carbon, such as wildfires, are not included. Emissions are generally grouped in the same categories as those used in Canada’s Air Pollutant Emissions Inventory (APEI). They are organized into seven source categories that are further broken down into 35 sectors and nine associated subsectors. See Annex 1 for source category organization and sector descriptions

The estimates in this inventory are based on the best available information at the time of compilation. Estimates of PM_2.5 emissions are consistent with those reported in Canada’s 2024 APEI. Please refer to Chapter 3 and Annex 2 of the APEI report (ECCC, 2024) for a description of the inventory development and estimation methods for PM_2.5. While the black carbon inventory provides valuable information on emissions in Canada, it does not distinguish localized sources of emissions within the provincial and territorial level aggregations. Work will continue to improve the quality, completeness, and accuracy of the inventory while quantifying the emissions that are not yet captured, and refining base data and estimation techniques. See Chapter 3 of the present report for more information on the black carbon inventory development.

References, Chapter 1, Introduction

[ECCC] Environment and Climate Change Canada. 2024. Canada’s Air Pollutant Emissions Inventory Report 1990–2022 : The Canadian government’s submission under the Convention on Long-Range Transboundary Air Pollution to the United Nations Economic Commission for Europe (March 2024).

[U.S EPA] U.S. Environmental Protection Agency. 2011. Black carbon research and future strategies (PDF, 231 KB). United States: Office of Research and Development.