The City of Saskatoon (City) is taking action on climate change and working to reduce greenhouse gas emissions. Supported by the Environmental Leadership goal of the 2013-2023 Strategic Plan, the City has implemented a number of initiatives and is developing a plan to improve Saskatoon's environmental performance.
Have your say on climate action in Saskatoon! Visit our climate change engagement page for more details.
What We're Doing
What is the City of Saskatoon already doing to address climate change?
The City of Saskatoon (City) is implementing a number of plans, policies, programs, and projects that protect and enhance Saskatoon’s environment. To learn more, read about the City of Saskatoon's Environmental Initiatives.
Although the City is making progress, we know more needs to be done. This is why we are working on a climate action plan to reduce greenhouse gas (GHG) emissions and adapt to the impacts of climate change.
DID YOU KNOW?
Diversion programs, including recycling and composting, reduced the GHG emissions from the landfill by 43,650 tonnes of CO2e in 2016. This is equivalent to removing approximately 9,200 cars from Saskatoon roadways annually. The City of Saskatoon’s landfill gas project also led to 55,794 tonnes CO2e of greenhouse reductions in 2016.
Saskatoon’s Climate Change Commitments
Since 2004, the City of Saskatoon (City) has been a member of the Federation of Canadian Municipalities (FCM) Partners for Climate Protection Program, which is a network of over 300 Canadian municipalities that have made a public commitment to reduce greenhouse gas (GHG) emissions and act on climate change.
In November 2015, the City also became a signatory of the Compact of Mayors (now Global Covenant of Mayors for Climate & Energy), which is an international alliance of cities and local governments with a shared long-term vision of promoting and supporting action to combat climate change. As part of this commitment, the City is required to develop and submit a climate action plan within three years of becoming a signatory that demonstrates how Saskatoon will deliver on its promise to mitigate GHG emissions.
Both programs are guiding the City towards specific environmental performance and climate action goals.
Learn more: Saskatoon’s Climate Change Commitments
Saskatoon’s Climate Action Plan
The City of Saskatoon (City) is currently creating a climate action plan that will focus on the local causes and effects of climate change, as well as solutions and opportunities that reflect what’s possible in our community. The plan will guide action and investment by the City, as well as outline ways that the City can support community initiatives. To be successful, the City will engage with residents, key stakeholders, and the Industrial Commercial and Institutional (ICI) sector to identify climate action priorities, opportunities, and areas of interest. Once we have a plan, we will need to work together to make sure we improve the health of our environment, the vibrancy and resiliency of our local economy, and the well-being of all people in Saskatoon.
Phase 1: Mitigation
The City is currently developing the mitigation phase of its climate action plan that will focus on addressing the root causes of climate change. The plan will outline how Saskatoon can meet its greenhouse gas (GHG) reduction targets for the community and City operations (learn more: Report - Climate Change Mitigation Business Plan - Opportunities).
It will also include:
- Opportunities to reduce GHG emissions within each sector,* including potential programs, policy tools, pilot projects, incentives, and educational programming (learn more: Climate Change Mitigation Opportunities for Saskatoon);
- A financial and feasibility analysis of GHG reduction initiatives, including long-term and short-term costs and savings;
- A comparison between climate action and climate inaction approaches, including risks, costs and other implications;
- The potential benefits and challenges that GHG reduction activities may have on the local economy; and
- The other benefits of greenhouse gas reduction activities, such as meeting other environmental, social, and economic priorities.
Once the climate action plan on mitigation is approved by City Council, an implementation strategy will be developed that will finalize:
- The set of GHG reduction initiatives that will be led and/or facilitated by the City of Saskatoon;
- Implementation timelines;
- Roles, responsibilities, and expectations (both of the City and community);
- Resource and budget implications; and
- A monitoring and evaluation plan.
Implementation will be ongoing and the strategy will be regularly updated to reflect progress, setbacks, and any other influencing factors.
*Sectors are based on the Global Protocol for Community-Scale Greenhouse Gas Emission Inventories and include: stationary (building) energy consumption; transportation; waste management; agriculture and land use; and industrial processing.
Phase 2: Adaptation
The second phase will provide adaptation strategies for Saskatoon, so that our community is prepared for the expected impacts of climate change, such as more severe weather. A climate adaptation strategy will identify risks to key infrastructure and support the City's Corporate Asset Management Plan.
Both the mitigation and adaptation strategies of the climate action plan will guide action and investment by the City, as well as outline ways that the City can support community initiatives.
Saskatoon’s Greenhouse Gas Emissions
The City of Saskatoon (City) measures greenhouse gas (GHG) emissions for its own operations and the community. The 2014 Greenhouse Gas Emissions Inventory is the first inventory to have been completed since Saskatoon’s 2003 Greenhouse Gas Emissions Inventory. Updates will be conducted annually in order to track progress and ensure the City and community are on-track to meet their GHG reduction targets.
The 2014 Greenhouse Gas Emissions Inventory showed an increase of 12% in community emissions since 2003. It is possible to reverse this trend as our community continues to grow.
GHG Emission Breakdown for Saskatoon (2014)
GHG Emission Breakdown for City of Saskatoon Operations (2014)
Saskatoon’s Greenhouse Gas Targets
In June 2017, the City adopted greenhouse gas (GHG) reduction targets that are in line with federal and international commitments. While the targets are ambitious, the City of Saskatoon (City) is committed to achieving them in partnership with the community.
- City Operations – Reduce GHG emissions by 40% below 2014 levels by 2023, and by 80% below 2014 levels by 2050.
- Community – Reduce GHG emissions by 15% below 2014 levels by 2023, and by 80% below 2014 levels by 2050.
These targets will be reviewed every 5 years and adjusted as necessary to reflect progress, best practices, and developments in the field.
Our Local Climate Context
How does and will climate change impact our community?
Climate change is happening, it affects everyone, and it impacts the things we love. It is not simply a problem for future generations, it is a problem for all of us here and now.
As a result of climate change, our community could experience:
- Increased flooding - which can lead to erosion, slope failures, water pollution, and damage to property and infrastructure;
- Dryer and/or hotter conditions - which can lead to more wildfires, poorer air quality, crop failure, higher energy use due to air conditioning, equipment and vehicle failure due to overheating, and property and infrastructure damage;
- Warmer winters - which can lead to an increase in pests and invasive species (e.g. Lyme Disease, Dutch Elm, West Nile), icier road conditions, less opportunities for winter recreation and cultural activities, and unpredictable freeze-thaw events that can damage plants, roads, and other infrastructure;
- More precipitation during winter in the form of rainfall - which can impact road maintenance, winter transportation, recreational activities, groundwater recharge, and spring flooding;
- More extreme weather events - “hundred-year” weather events will no longer happen just once every hundred years, but much more frequently, which can lead to health and safety risks, as well as changes to insurance premiums, deductibles and coverages;
- A longer growing season - which could be accompanied by increased risks of excessive heat, drought, pests, invasive species, and limited agricultural benefits;
- Rapid melting of mountain snow and glaciers - which can lead to changes in our river flows, water quality, water temperatures, and aquatic habitat/species health; and
- Losses and/or changes to habitat - which can threaten native species, reduce ecosystem services, and result in losses to recreational, spiritual, and educational opportunities in nature.
To learn more about how a changing climate could impact Saskatoon, view the Saskatoon Environmental Advisory Committee’s video.
“[Allowing a High Carbon scenario to occur] would be a total game changer for the Prairie landscape. This rapid shift would present our children with an entirely different climate, which would necessitate a complete reworking of how we live and thrive in our environment. We are currently not ready for this future. Our ecosystems, economies and cultures will be stressed by these dramatic changes. We need to be prepared and, as much as possible, prevent the High Carbon world from becoming a reality.” -Prairie Climate Atlas
On a global scale, the following trends are emerging:
- Temperatures are rising;
- Extreme events are becoming more frequent;
- Oceans are warming;
- Ice sheets are shrinking;
- Glaciers are retreating;
- Snow cover is decreasing;
- Sea level is rising;
- Arctic sea ice is declining; and
- Ocean pH is decreasing, leading to ocean acidification. This negatively impacts coral reefs, shellfish, and other sensitive habitats and species.
Sources: Prairie Climate Atlas, NASA
2017 Environmental Awareness Survey Results
The City of Saskatoon (City) conducted an Environmental Awareness Survey in June 2017 that was representative of Saskatoon’s population. The focus was to gauge how residents and the Industrial Commercial and Institutional (ICI) sector currently understand climate change and the environment.
Read the results:
- 2017 Environmental Survey - Residential Results
- 2017 Environmental Survey - Industrial Commercial Institutional Sector Results
What is carbon pricing? And what will it mean for Saskatchewan?
Carbon pricing (also referred to as a carbon tax or levy) is a way to put a price on carbon pollution, which is an efficient and effective way to reduce greenhouse gas (GHG) emissions.
Carbon pricing is intended to encourage innovation as businesses, industry, and households seek out new ways to increase efficiencies and pollute less. The revenue generated from carbon pricing is intended to stay within the province or territory where it was levied. Other jurisdictions have used carbon tax revenue to invest in clean solutions, drive environmental innovation, and support businesses, industries and people who have less ability to adapt to increasing costs.
The Federal Government has announced that provinces have until the end of 2018 to submit carbon pricing plans before a national price on carbon is introduced. If Saskatchewan does not enact a carbon pricing system by the end of 2018, a “Carbon Pricing Backstop” may come into place.
Sources: Government of Canada; Pan Canadian Framework; Canada’s Ecofiscal Commission
About Climate Change
What causes climate change?
Our planet’s climate has changed throughout history, mostly due to very small variations in the earth’s orbit that change the amount of solar energy our planet receives. For example, there have been seven glacial advance-and-retreat events in the last 650,000 years, with the last ice age ending about 7,000 years ago.
Although natural patterns have led to changes in our planet’s climate in the past, research shows that the current warming trend is of particular significance because:
- There is undeniable evidence that climate change is being influenced by human activity. In fact, about 97% of scientists agree that human-caused climate change is happening here and now and it affects everyone;
- The current atmospheric concentrations of carbon dioxide, methane, and nitrous oxide have not been this high in at least the last 800,000 years;
- Over the past 250 years (since the industrial revolution), the concentration of greenhouse gases in the atmosphere has been rising at an ever-increasing rate; and
- Most of the warming has occurred in the past 35 years, with 16 of the 17 warmest years on record occurring since 2001.
Some of the human activities that contribute to climate change include:
- Burning fossil fuels and biomass;
- Water, energy and resource use;
- Changes in land use and habitat loss, such as deforestation and the removal of grasslands;
- Industrial and chemical processing;
- Forms of transportation that require fossil fuels;
- Agricultural activities, such as the production and use of chemical fertilizers, intensive livestock farming, and inefficient food distribution systems;
- Landfills and waste processing; and
- Water and sewage treatment.
Sources: Intergovernmental Panel on Climate Change (IPCC); NASA; NASA Earth Observatory; American Association for the Advancement of Science
2 degrees doesn’t sound like much. Why is keeping global temperature rise well below 2° Celsius important?
The international Paris Agreement commits nations to undertake ambitious efforts to combat climate change in order to keep average global temperature rise well below 2 ˚C (and ideally limiting it to 1.5 ˚C) relative to pre-industrial values.
The reason? We are changing the earth’s temperature very fast.* Although a 2˚C temperature increase may not seem like much, small changes in the Earth's average temperature can lead to big impacts on our community. Allowing the average global temperature to rise by 2˚C would have extreme and irreversible impacts around the world, including longer heat waves, more intense rain storms, much higher sea levels, losses in fresh water availability, severely degraded coral reefs, and crop failures.
It is technically possible to limit global average temperature rise to below 2˚C if we peak emissions soon and steadily reduce them.
*The global average surface temperature rose from 0.6 to 0.9° C between 1906 and 2005, and the rate of temperature increase has nearly doubled in the last 50 years. If we do not make significant efforts to address climate change promptly, we could see the global temperature rise by as much as 3-4° C by the end of the century, while the Canadian prairies could rise by almost 7° C. To put this in context, a 5° C change in average global temperature is the difference between now and the last ice age.
Sources: Prairie Climate Atlas, NASA, United Nations; CitiScope
Food For Thought:
Think about your body temperature. Your body stays fairly close to 37° C and can only function properly within a very narrow temperature range. If your temperature spikes by only 1 degree to 38° C, that indicates that you have a fever and are sick. When we’re sick, it often impacts our entire body.
Now consider that the planet is like your body. Its current ecosystems and species (including humans) can only function properly within a fairly consistent temperature range. As soon as the temperature changes or fluctuates, even by only a small amount, it can have severe impacts on the entire earth.
What are the benefits of acting on climate change?
There are a number of benefits that can result from taking action to reduce greenhouse gas emissions and adapt to climate change, including:
- Improvements to individual and public health
- Economic development
- Improved land-use planning and development patterns
- Investments in research & development
- Lower utility bills
- A more inclusive society
- Smaller ecological footprint
- Equity and quality of life improvements
- A more accessible city
- A safer community
- Strategic regional planning
- Quieter city
- More access to natural, recreational, cultural, and educational green spaces
- Improved protection, enhancement, and development of natural and naturalized areas
- Less pollution
- Improvements to public services, infrastructure, and delivery models
- Strategic partnerships
- Technological, social, and economic improvements
- Decreased burden on future generations
To learn about these benefits in more detail, read Benefits of Acting on Climate Change.
Sources: City of Toronto’s TransformTO; Acadia Center’s Energy Efficiency: Engine of Economic Growth in Canada; Leyden’s Social capital and the built environment
What are the risks of waiting to act on climate change?
Research on climate change identifies that action is urgently needed to reduce the risks, impacts, and costs of climate change. And while taking action on climate change can seem daunting, especially in times of fiscal constraint, by delaying action we risk:
- Paying more.
- Responding to climate events in reactive and unplanned ways, which can put stressors on social, economic, and environmental systems, such as unanticipated costs, damages and maintenance needs.
- Allowing climate impacts to persist and become worse by not addressing the ‘upstream’ issue of reducing greenhouse gas emissions.
- Placing financial, environmental, and social burdens on future decision-makers and residents.
- Facing irreversible damage that will make individuals and communities less resilient in the face of a changing climate.
- Building unsuitable/inadequate infrastructure that will lock our city into the effects of these decisions for decades to come, if not centuries.
- Creating stranded assets and investments that do not provide value in the future.
- Amplifying vulnerabilities for marginalized people: “poverty and marginalization not only reduces people’s capacity to absorb rising food, water, and energy prices, but it also limits their ability to invest in resources and prepare for the impacts of climate change. Following a disaster, it is much harder for low-income and marginalised communities to rebuild, as these groups are less likely to have the social capital and resources to effectively advocate to have their needs met.” -City of Toronto, TransformTO
- Not doing our part to reduce and manage our own environmental impacts.
Sources: City of Toronto’s TransformTO
Why is it important to take action on climate change now?
What we do as a community matters. Did you know that:
- Cities are responsible for up to 70% of greenhouse gas (GHG) emissions while occupying only 2% of the world’s land mass;
- Saskatchewan is the highest GHG emitting province per capita in the country; and
- Canada is one of the top 10 emitting nations globally?
We are at risk of pushing our climate system towards abrupt, unpredictable, and potentially irreversible changes with highly damaging impacts. Acting on climate change now is important because it will reduce our risks, lead to a number of benefits, and save us money. The changes we choose to make (or not make) will determine our short- and long-term future; therefore, the decisions we make today matter.
“The decisions that are made today regarding the built form, natural systems, and social structures will commit our communities to a certain way of life for years to come. This ‘lock-in’ effect is an extremely important consideration as municipal staff and elected officials strive to prepare our cities, towns, and regions for the future. These choices will need to take into account the scale, rate, and complexity of the risks presented by a changing climate.” -ICLEI
Sources: UN Habitat, Cities and Climate Change; Conference Board of Canada; Environment and Climate Change Canada; International Energy Agency, Energy Technology Perspectives
What will it cost to act on climate change? What will it cost if we do not act on climate change?
The cost scenarios of climate action (i.e. investing in solutions today) and climate inaction (i.e. business-as-usual) are currently being explored for Saskatoon.
Whether we act or don’t act on climate change, we will have to spend money. That being said, research and experience from other jurisdictions show that the sooner communities act to mitigate and adapt to climate change, the more money is saved and future costs reduced. In fact, studies conducted by economists and scientists show that the costs of maintaining a “business-as-usual” approach (i.e. not acting on climate change now, but reacting to climate change in the future) are actually higher than investing in solutions today. This suggests that taking action as soon as possible is the most fiscally responsible decision because the sooner we act, the lower the cost.
So our choices matter. Will we choose to solve this problem once and for all and invest in climate action today? Or will we choose to delay action and accept the costs and risks associated with waiting to act on climate change?
The decisions we need to make are not about choosing the environment over the economy, or vice versa. Scientists working with economists believe there are ways to manage the risks and costs of climate change while simultaneously achieving current and future economic prosperity.
“What is perhaps most surprising is that looking at the potential total spend on energy over the next quarter century … the cost of following a low carbon route at $190.2 trillion is actually cheaper than our ‘Inaction’ scenario at $192 trillion. [This] is due to the rapidly falling costs of renewables, which combined with lower fuel usage from energy efficiency investments actually result in significantly lower long term fuel bill. Yes, we have to invest more in the early years, but we potentially save later, not to mention the liabilities of climate change that we potentially avoid.” -Citigroup, Why a Low Carbon Future Doesn’t Have to Cost the Earth
Sources: Citigroup, Why a Low Carbon Future Doesn’t Have to Cost the Earth; National Resources Canada; City of Toronto, Transform TO; The Economist, The cost of inaction: Recognising the value at risk from climate change; OECD, Climate change: Consequences of inaction
What is the government's role in addressing climate change?
Canadian municipalities have a significant role to play in addressing the impacts of climate change and reducing greenhouse gas emissions. They make decisions on public transit, waste management, infrastructure, buildings, air quality, and water quality, as well as influence the quality of life for people living in cities. These activities can be significant sources of greenhouse gas emissions.
“Responding to climate change must occur at all levels of government, including local governments. The impacts of a changing climate, such as reduced water availability and infrastructure loss, will be experienced at the local level first. Therefore, local governments have a need and a responsibility to take a leadership role in responding to these changes.” -ICLEI
The provincial government is responsible for greenhouse gas (GHG) emissions in a number of sectors, including electricity generation; residential, commercial, and institutional buildings; transportation; agriculture; and waste management. Provinces are also responsible for implementing their own climate policies and sustainable development strategies, regulating their natural resources sector, supporting clean technology, and taking action to improve air quality and aquatic ecosystems.
The Government of Saskatchewan influences the climate mitigation options available to municipalities, such as through the Cities Act and the Planning and Development Act, or through province-wide standards that are adopted, such as plumbing and building codes and environmental regulations.
In December 2017, the Government of Saskatchewan released “Prairie Resilience: A Made-in Saskatchewan Climate Change Strategy.” Throughout 2018, the provincial government will be developing an implementation plan that includes consultation and engagement. Areas of the provincial climate change strategy that relate to the City of Saskatoon’s climate mitigation planning include:
- Achieving up to 50 per cent electricity capacity from renewables;
- Adopting the 2015 National Building Code, with an option to label buildings for energy performance; and
- Prioritizing funding for municipal waste and sewage management projects that reduce, capture and use GHG emissions and biogas.
To learn more about the Government of Saskatchewan’s climate change strategy, visit the provincial government's Climate Change website.
The federal government plays a role in environmental protection and facilitating action on climate change. For example, they track and manage wildlife populations; research ecosystem health; support habitat recovery; preserve and enhance the quality of the natural environment, including water, air, soil, flora and fauna; assess environmental risk; monitor weather and climate; and support policy and legislative action.
The Government of Canada has established the Pan-Canadian Framework on Clean Growth and Climate Change. The plan includes pricing carbon pollution and measures to achieve reductions across all sectors of the economy.
The goal of the international Paris Agreement is to keep average global temperature rise below 2˚C (and ideally, 1.5 ˚C) relative to pre-industrial levels. “Scientists believe that keeping planetary warming below this level is necessary to avert the worst effects of global climate change” (CitiScope). Achieving this goal will require action by all communities across the globe.
195 countries (including Canada) have signed the Paris Agreement, which commits nations to undertake ambitious efforts to reduce greenhouse gas emissions and adapt to the impacts of climate change. The Paris Agreement was adopted on December 12, 2015 at the twenty-first session of the Conference of the Parties to the United Nations Framework Convention on Climate Change.
Sources: ICLEI; Government of Canada; Province of Saskatchewan; United Nations Framework Convention on Climate Change; CitiScope, Explainer: What is the Paris Agreement on climate change and what does it mean for cities?
Adaptation and Mitigation
Both climate adaptation and climate mitigation are needed in order to effectively respond to the short-and long-term disturbances of climate change.
Climate adaptation refers to activities that reduce the risks and unavoidable negative impacts of climate change. Adaption limits our vulnerability to the effects of climate change and helps reduce damages. It requires adjusting our communities and our lifestyles to be responsive to actual and expected future climate scenarios.
Climate mitigation refers to activities that address the root causes of climate change by reducing the rate and amount of greenhouse gas emissions. Mitigation initiatives slow down climate change and temperature increases by reducing the amount of new greenhouse gas emissions being added to the atmosphere, the benefits of which occur on both local and global scales.
Adaptation and mitigation activities require a combination of solutions in areas such as policy, planning, finance and investment, technology, education, and behaviour change. These actions will require adjustments to the way we live, as well as changes to how our communities are designed. The good news is that climate mitigation and adaptation activities lead to a variety of benefits that can improve our quality of life.
“Local governments have jurisdiction over important service sectors such as land use planning, transportation infrastructure, buildings, waste management, and water services, making them well-positioned to develop policies that meet specific environmental, economic, and social goals. As municipalities work to address climate change, it is important to note the ways in which mitigation and adaptation can be integrated together into planning processes.” -ICLEI
Organic matter such as trees and wood products.
Carbon Dioxide (CO2)
Carbon dioxide (CO2) is the main greenhouse gas emitted by human activities.
- Human sources: burning fossil fuels waste, and biomass; clearing land, such as forests and grasslands; and industrial processes such as the production of cement.
- Natural sources: volcanoes; wildfires; the decay of organic matter; and respiration (breathing).
Carbon Dioxide Equivalents (CO2e)
Greenhouse gas emissions are often measured in terms of Carbon Dioxide Equivalents (CO2e) to describe the varying potencies of different greenhouse gases using a common unit. CO2e is calculated by multiplying the amount of gas by its associated global warming potential (GWP). Carbon dioxide (CO2) is the reference gas against which other greenhouse gases are measured; therefore, CO2 has a CO2e of 1.
Climate refers to long-term changes in weather, averaged over many years (decades, centuries, or millennia) to determine regional trends. A region’s climate usually experiences seasonal variations (i.e. in winter, spring, summer, and fall).
Climate change refers to a long-term change in our planet’s overall climate, the impacts of which can vary drastically from region to region. Climate change effects temperature, precipitation, wind, water levels, ecosystems, and the frequency and severity of storm events, which can lead to harmful and irreversible impacts on people, the environment, and other species.
Ecosystem Services refer to the benefits we receive from nature, including: food and medicine; air quality; water purification; renewable and non-renewable energy resources; fiber resources; habitat, wildlife and biodiversity; pollination and seed dispersal; pest management; soil formation; flood protection; prevention of soil erosion and sediment build-up; nutrient cycling and chemical regulation; mental, physical, and emotional health; disease regulation; genetic resources; climate stability and carbon sequestration; spiritual enrichment; educational opportunities; recreation; aesthetic experiences; natural and cultural history; and city beautification.
An emission factor is a value that quantifies the greenhouse gas emissions associated with a particular fuel or activity. They can be country-, industry-, or technology-specific.
“For example, the combustion of natural gas in a boiler results in emissions of GHGs such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Each has published emission factors that relate its emission rates to quantities of natural gas burned.” -Environment and Climate Change Canada
Excessive richness of nutrients in a body of water, which causes a dense growth of plant life (i.e. algae blooms) and can lead to death of animal life due to a lack of oxygen.
Fluorinated gases include sulfur hexafluoride (SF6) (22,800 CO2e), hydrofluorocarbons (HFCs) (124 to 14,800 CO2e), perfluorocarbons (PFCs) (7,390 to 12,200 CO2e), and nitrogen trifluoride (NF3) (17,200 CO2e). These man-made gases are typically emitted in smaller quantities, but because they are so potent, they are sometimes referred to as High Global Warming Potential gases.
- Human sources: refrigerants; aerosol propellants; foam blowing agents; solvents; fire retardants; and industrial activities.
- Natural sources: none.
Non-renewable resources, such as coal, natural gas, oil.
Global warming refers specifically to a long-term increase in Earth's average temperature. Currently, our earth is experiencing a period of rapid warming; therefore, the term global warming is also used to describe the current climatic changes occurring on earth.
Global Warming Potential (GWP)
Global Warming Potential (GWP) measurements are calculated for each greenhouse gas to reflect how long they remain in the atmosphere, on average, and how strongly they absorb energy. Gases with a higher GWP absorb more energy, per pound, than gases with a lower GWP, and thus contribute more to warming the earth.
The greenhouse effect is a natural process whereby incoming solar (infrared) radiation warms the earth. Some of the sun’s energy and heat is reflected back into space, while the rest is absorbed by the earth’s land and water bodies or trapped by greenhouse gases in the atmosphere. The concentration of greenhouse gases in our atmosphere determines how much heat our planet absorbs.
Currently, human activities are increasing the amount of greenhouse gases released into the atmosphere and increasing concentrations faster than can be offset by natural sequestration processes, which is causing the earth’s temperature to rise and the climate to change.
Greenhouse Gases (GHGs)
Greenhouse gases (GHGs) are the gases in the atmosphere that absorb and emit solar (infrared) radiation and cause the earth to warm. Some greenhouse gases occur naturally, while others are released (emitted) due to human activities. GHGs can also be sequestered; for example, plant life sequesters CO2 during the process of photosynthesis.
The most significant GHGs include: carbon dioxide (CO2), methane (CH4), nitrogen oxides (NOX), fluorinated gases, ground-level ozone (O3), and water vapor (H2O).
Greenhouse gas emissions are often measured in terms of Carbon Dioxide Equivalents (CO2e).
Ground-Level Ozone (O3)
Ground-level (tropospheric) ozone (O3) is a result of air pollution and is different from naturally occurring stratospheric ozone*. Ozone at ground level is the main ingredient in “smog.”
- Human sources: pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources that chemically react in the presence of sunlight.
- Natural sources: settling of stratospheric ozone towards the earth’s surface.
*Stratospheric ozone occurs naturally in the upper atmosphere, where it forms a protective layer that shields us from the sun's ultraviolet rays. This beneficial ozone has been partially destroyed by manmade chemicals, causing what is commonly referred to as a “hole in the ozone layer.”
Methane (CH4) is a greenhouse gas 25 times more potent than carbon dioxide (25 CO2e). It often occurs as a result of decaying organic material in anaerobic (airless) environments.
- Human sources: the production, removal, transportation, and burning of fossil fuels; burning biomass; decomposition in landfills and sewage treatment plants; and agricultural activities such as livestock farming and rice cultivation.
- Natural sources: volcanoes; wildfires; seepage vents in the seafloor; melting permafrost; and waterlogged environments, such as wetlands.
Nitrogen Oxides (NOX)
Nitrogen oxides (NOX) include emissions from nitric oxide (NO) and nitrogen dioxide (NO2) (298 CO2e). NOX contribute to acid rain, eutrophication of water bodies, and the formation of ground-level ozone and fine particulate matter.
- Human sources: burning and processing fossil fuels and solid waste; mining; motor vehicles and engines; wastewater management; agricultural processes (livestock, crop production and fertilizer); and other industrial activities.
- Natural sources: lightning; wildfires; and microbial processes in soils.
Particulate matter, also known as particle pollution, is a mixture of extremely small particles and liquid droplets that get into the air. Once inhaled, these particles can affect the heart and lungs and cause serious health effects.
Sequestration (often referred to as “carbon sinks”) refers to the removal of greenhouse gases from the atmosphere through natural (physical, chemical, biological) processes. Research and technology are currently being explored to sequester greenhouse gases through human processes.
The Brundtland Report, also known as Our Common Future, is a foundational United Nations report from 1987. Their definition of sustainability is: “Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” In 1992, another key document about sustainability was produced, the Earth Charter. The sustainability principles outlined in the charter stress the importance of: respecting and caring for life; ecological integrity; social and economic justice; democracy; nonviolence; and peace for both present and future generations.
Water Vapor (H2O)
As the earth warms due to rising levels of greenhouse gases, concentrations of water vapour (H2O) increase due to evaporation, further intensifying the greenhouse effect. This in turn causes more warming, which causes an additional increase in water vapour, in a self-reinforcing cycle.
"It’s true that water vapor is the largest contributor to the Earth’s greenhouse effect. … However, water vapor does not control the Earth’s temperature, but is instead controlled by the temperature.” -American Chemical Society
Weather refers to short-term changes in temperature, clouds, precipitation, humidity, and wind in a region or a city. Weather can vary greatly from one day to the next, or even within the same day.
Sources: Intergovernmental Panel on Climate Change (IPCC); NASA; Environmental Protection Agency (EPA); Environment and Climate Change Canada; Britannica; Greenhouse Gas Protocol; ICLEI; Natural Resources Canada