Short-lived climate pollutants

Overview

Short-lived climate pollutants (SLCPs) are a group of greenhouse gases and air pollutants that have a near-term warming impact on climate and can affect air quality. SLCPs include black carbon, methane, ground-level ozone, and hydrofluorocarbons (HFCs). Recent studies suggest that global action on carbon dioxide and SLCPs together is needed to meet the temperature goals in the Paris Agreement.

Canada’s strategy to further reduce SLCPs

To help guide future actions in reducing these pollutants, Environment and Climate Change Canada (ECCC) has developed a Strategy on Short-Lived Climate Pollutants, as part of a holistic approach for meeting climate and air quality objectives. This Strategy is complementary to the Pan-Canadian Framework for Clean Growth and Climate Change.

Canada’s strategy addresses SLCPs through five pillars for action:

1. Enhancing domestic mitigation efforts;
2. Enhancing science and communications to broaden understanding;
3. Engaging internationally, and building partnerships to reduce SLCPs on a global scale;
4. Coordination of Government of Canada activities; and
5. Collaborating with provincial and territorial governments and other partners.

Implementation of this Strategy will: generate reductions from all key SLCP emissions sources, achieve health and climate benefits, signal Canada’s continued commitment to reducing emissions of SLCPs at home and abroad, and position Canada in line with leading jurisdictions.

Key sources of SLCP emissions in Canada include:

• on and off-road transportation;
• wood burning appliances
• oil and gas facilities;
• landfills; and
• stationary diesel engines used in many applications throughout Canada—including for power generation in Northern, remote and Indigenous communities.

Types of short-lived climate pollutants

Black carbon

Black carbon emissions are estimated to be the third largest contributor to current climate warming, after CO₂ and methane.

Short-term and long-term exposure to particulate matter (PM_2.5) is associated with a broad range of human health impacts, including respiratory and cardiovascular effects as well as premature death. Black carbon is a component of fine particulate matter (PM_2.5) generated by the incomplete combustion of fossil fuels and biomass.

The transportation sector is estimated to be the largest source of black carbon emissions in Canada, accounting for over half of Canada’s total black carbon emissions in 2014. Wood burning appliances and stationary diesel engines are also sources of black carbon emissions.

Methane

Methane is a potent greenhouse gas responsible for about 25 percent of the human-caused global warming. A tonne of methane is estimated to have 84 times the warming power of carbon dioxide over a 20-year period.

The oil and gas sector accounted for 44 percent of Canada’s methane emissions in 2014. The emissions were largely from unintentional sources, such as methane being vented into the air during oil and gas production (42 percent of national total). The remainder of Canada’s methane emissions is largely from agriculture and solid waste disposal (e.g. landfills).

Hydroflurocarbons

Hydroflurocarbons (HFCs) are manmade substances introduced onto the global market as replacements for ozone-depleting substances, which have almost completely been phased out in Canada as a result of the Montreal Protocol.

Although not ozone-depleting, HFCs are powerful greenhouse gases, some with global warming potentials thousands of times higher than carbon dioxide. Globally, HFCs are considered the fastest-growing greenhouse gases in most of the world, increasing at a rate of 10 to 15 percent per year.

HFCs are used in aerosols, foams, air-conditioning and refrigeration, where their use has increased in place of ozone-depleting substances.

Ground-level ozone

Ground-level ozone is formed when nitrogen oxides (NO_x) and volatile organic compounds (VOCs) react in the presence of sunlight and stagnant air.

Ground-level ozone is a key component of smog and a contributor to climate warming.

It has significant effects on human health, damages plants and affects agricultural production.

In Canada, the transportation and oil and gas sectors as well as residential wood combustion are significant sources of NO_x and VOC emissions.

Related resources

• Strategy on Short-Lived Climate Pollutants
• Canada’s Black Carbon Inventory
• International engagement on SLCPs
  • Climate and Clean Air Coalition
  • Global Methane Initiative