Short-lived climate pollutants
Overview
Short-lived climate pollutants (SLCPs) affect air quality and cause near-term climate warming. Studies show that the goals of the Paris agreement cannot be met without significant global action on SLCPs. Reducing SLCPs is an important part of Canada’s plan to limit climate change.
Types of short-lived climate pollutants
Black carbon
Black carbon is a key cause of climate warming, particularly in polar regions. When black carbon lands on snow and ice, it absorbs heat and increases warming, speeding up the melting process.
Black carbon is a form of fine particulate matter (PM2.5) created when burning fossil fuels and wood. Scientific studies have connected exposure to PM2.5 to negative health impacts, including:
- respiratory illness
- cardiovascular illness
- an increased risk of death
Over half of the black carbon emitted in Canada in 2023 came from vehicle exhaust. Home wood burning and diesel engines (for example, for “off-grid” power generation) are also key sources of black carbon.
Methane
Methane is a potent greenhouse gas that causes about 30% of all human-caused warming. A tonne of methane has roughly 84 times the warming power of carbon dioxide (CO2) over a 20-year period. Methane also reacts in the air to create ozone, which also worsens air quality and warms climate.
The oil and gas sector accounted for 48% of Canada’s methane emissions in 2023. Agriculture (28%) and landfills (18%) are the other main emission sources. Canada has outlined its actions to reduce methane in Faster and Further: Canada's Methane Strategy. The strategy also supports the Global Methane Pledge efforts to reduce global methane emissions by 30% by 2030.
Hydroflurocarbons
Manufacturers use HFCs in aerosols, foams, air-conditioning, and refrigeration. HFCs are strong greenhouse gases that warm the air thousands of times more efficiently than CO2.
The Kigali Amendment to the Montreal Protocol aims to phase down global HFC usage. Canada ratified the Amendment in 2017 and has reduced its HFC consumption by 54% (as of 2024). This is a greater reduction than the 40% target that Canada had set.
Ozone
The stratospheric ozone layer (~ 15-30 km altitude) protects humans from harmful UV rays. However, at lower altitudes in the troposphere (~0-12 km) ozone is a greenhouse gas. At ground-level, ozone is a key component of smog. It harms human and animal health, and damages crops and other plants.
Tropospheric ozone forms when nitrogen oxides (NOx) react with methane and other volatile organic compounds (VOCs). Key sources of NOx and VOCs include vehicles, the oil and gas sector, and home wood burning.
Canada’s strategy to reduce SLCPs
Environment and Climate Change Canada developed an SLCP strategy to help Canada meet its climate and air quality goals. With this Strategy, Canada will:
- reduce all key SLCP sources
- gain health and climate benefits
- show Canada’s commitment to reducing emissions of SLCPs at home and abroad
- position Canada in line with global leaders in SLCP action
Canada engaging internationally on SLCPs
Arctic Council
Countries of the Arctic Council have committed to report on their work to reduce black carbon and methane. Countries must also report emissions trends and projections. These reports track progress toward the Council’s goal of lowering black carbon emissions by 25-33% below 2013 levels by 2025.
Canada’s 2024 report shows it is on track to meet its share of the goal. Canada’s black carbon emissions were 31% below 2013 levels in 2022. Projections estimate that emissions may be 38% below 2013 levels by 2025. Methane emissions were 22% below 2005 levels in 2022.
Global Methane Initiative
The Global Methane Initiative (GMI) works to cut methane emissions and support use of methane as an energy source. It brings together 49 countries and more than 1,300 partners from the private sector, research, development banks, and nonprofits.
GMI focuses on three major sources of methane:
- oil and gas
- biogas (from landfills, wastewater, and agriculture)
- coal mining
Canada served as chair or co-chair of the GMI Steering Committee from 2016 to 2023. Canada is also the co-chair of the oil & gas and biogas subcommittees. In 2022, Canada pledged $2 million to support methane reduction projects in developing countries recommended by GMI.
Climate and Clean Air Coalition
The Climate and Clean Air Coalition (CCAC) is a leading forum in raising awareness of SLCPs and supporting local and global efforts to reduce them. It brings together over 200 partners from governments, businesses, and organizations. CCAC focuses on how reducing SLCPs can address short-term climate change while also:
- protecting the environment
- improving public health
- strengthening food and energy security