Drivers and Impacts of Greenhouse Gas Emissions
Most greenhouse gases (GHGs) have both natural and human sources. According to the Intergovernmental Panel on Climate Change (IPCC), human-caused GHG emissions disrupt the natural processes occurring in the atmosphere and are extremely likely to be the dominant cause of the observed warming that has occurred since the mid-20th century. Globally, almost 80% of GHG emissions from human sources come from the burning of fossil fuels and industrial processes. Specific activities include the following: driving vehicles, electricity production, heating and cooling of buildings, operation of appliances and equipment, production and transportation of goods, and provision of services and transportation for communities. In 2013, about 25% of Canada's total GHG emissions came from the oil and gas sector, 23% from transportation, 12% from electricity generation and 12% from buildings.
Global GHG emissions grew by approximately 42% between 1990 and 2011,Footnote  with the bulk of the growth occurring in emerging markets and developing countries. During this period, Canada's share of total global GHG emissions decreased slightly, and is now less than 2%.
Overview of the key drivers of greenhouse gas emissions
A wide variety of factors have an influence on the level of GHG emissions in Canada. These include Canada's physical geography, demographic changes in its population and economic growth.
Canada has a highly variable climate. This contributes to relatively higher energy use for space heating and cooling in buildings, compared with other industrialized countries. While vast, Canada is also sparsely populated, which leads to longer travel times and higher demand for transportation than in smaller and/or more densely populated countries. In addition, Canada has seen faster than average population and economic growth relative to other developed countries between 2000 and 2012, as well as high international demand for its natural resources, including oil and gas.
Despite these challenges, over the past two decades, Canada has seen a "de-coupling" between growth of the economy and GHG emissions as technological improvements and regulations have been adopted and implemented in various economic sectors, particularly for electricity generation.
Other important factors influencing GHG emissions include the adoption of more efficient practices and equipment by consumers and industry because today they are more knowledgeable of their choices and the impacts of those choices on the environment. Examples include how people commute to work, where businesses decide to locate their manufacturing facilities and the decisions made to increase the efficiency of industrial processes or to manufacture more energy-efficient products.
Overview of the key impacts of greenhouse gas emissions
The release of GHGs and their increasing concentration in the atmosphere are already having an impact on the environment, human health and the economy. These impacts are expected to become more severe, unless concerted efforts to reduce emissions are undertaken.
- Overall average annual temperatures are expected to increase.
- Snow, sea ice and glacier coverage will decrease because of higher temperatures, resulting in rising sea levels and increased coastal flooding. Rising temperatures will also thaw permafrost in the Arctic.
- Overall precipitation levels are expected to increase across most of the country and during all seasons, except for parts of southern Canada where there are indications of an expected decrease in summer and fall precipitation.
- The increase in precipitation is expected to be combined with more frequent heavy precipitation events, resulting in higher risks of flooding.
- Heat waves are likely to increase in frequency and severity, resulting in higher risks of forest fires.
- Many wildlife species will have difficulty adapting to a warmer climate and will likely be subject to greater stress from diseases and invasive species.
Human health impacts
- Higher temperatures and more frequent and severe extreme weather events may increase the risk of deaths from dehydration and heat stroke, and of injuries from intense local weather changes.
- There may be a greater risk of respiratory and cardiovascular problems and certain types of cancers, as temperatures rise and exacerbate air pollution.
- The risk of water-, food-, vector- and rodent-borne diseases may increase.
- People living in Canada's northern communities, and vulnerable populations such as children and the elderly, are expected to be the most affected by the changes.
- Agriculture, forestry, tourism and recreation may be affected by changing weather patterns.
- Human health impacts are expected to place additional economic stress on health and social support systems.
- Damage to infrastructure (e.g., roads and bridges) caused by extreme weather events, thawing permafrost and rising sea levels is expected to increase, impacting local populations and resource development.
How can we help?
Addressing climate change requires action from all countries. Governments, businesses and individuals need to take significant steps to reduce emissions by using resources more efficiently and adopting new and cleaner technologies.
We can reduce our GHG emissions at home, at work and in our everyday activities. We can make a difference by changing our behaviour and making lifestyle decisions that reduce emissions.
For more information on how individual Canadians can help to reduce GHG emissions, consult the Top Ten Things You Can Do to Help on Canada's Action on Climate Change website.
The Government of Canada is implementing a sector-by-sector regulatory approach to reduce GHG emissions that protects the environment and supports economic prosperity. The government has already taken action on two of Canada’s largest sources of GHG emissions: transportation and electricity. To learn more about the Government of Canada’s actions to address climate change, visit Canada's Action on Climate Change website.
To learn more about the expected impact of GHG regulations developed by the government of Canada, consult the Regulatory Impact Analysis Statement (also known as a RIAS) which accompanies each regulation. The RIAS outlines the reasons behind the development of a particular regulation, its objectives and its expected costs and benefits. The RIAS also includes details about consultations that were conducted and about how the government intends to track the performance of the regulation.
- Environment Canada (2013) Climate Trends and Variations Bulletin–Annual 2013 Summary.
- Environment Canada (2015) National Inventory Report 1990–2013: Greenhouse Gas Sources and Sinks in Canada.
- Environment Canada (2014) Canada's Emission Trends 2014.
- Natural Ressources Canada (2008) From Impacts to Adaptation: Canada in a Changing Climate 2007.
- Natural Resources Canada (2014) Canada in a Changing Climate: Sector Perspectives on Impacts and Adaptation.
- Health Canada (2008) Human Health in a Changing Climate: A Canadian Assessment of Vulnerabilities and Adaptive Capacity.
- Intergovernmental Panel on Climate Change (2014) Climate Change 2014: Impacts, Adaptation and Vulnerability.
- International Energy Agency (2014) CO2 Emissions From Fuel Combustion Highlights 2014.
- Greenhouse Gas Emissions by Economic Sector
- Greenhouse Gas Emissions by Province and Territory
- Global Greenhouse Gas Emissions
- Environment Canada - Climate Change
- Health Canada - Climate Change and Health
- Natural Resources Canada - Climate Change Impacts and Adaptations
- United Nations Framework Convention on Climate Change
- Intergovernmental Panel on Climate Change
Below is a list of regulations enacted by the federal government that contribute to reducing emissions of GHGs.
- Renewable Fuels Regulations (2010, amended 2011 and 2013)
- Passenger Automobile and Light Truck Greenhouse Gas Emission Regulations (2010, amended 2014)
- Reduction of Carbon Dioxide Emissions from Coal-Fired Generation of Electricity Regulations (2012)
- Heavy-duty Vehicle and Engine Greenhouse Gas Emission Regulations (2013)
The following regulation has been proposed to further reduce emissions of GHGs:
- Regulations Amending the On-Road Vehicle and Engine Emission Regulations and Other Regulations Made Under the Canadian Environmental Protection Act, 1999 (2014)
In addition, the Government of Canada has announced:
- That it intends to start developing more stringent standards to further reduce GHG emissions and fuel consumption from post-2018 model year heavy-duty vehicles and engines, building on existing regulations for the 2014 to 2018 model years; and
- That it is developing regulations to control the manufacture, import and use of hydrofluorocarbons (HFCs), which are potent GHGs.
- Date Modified: