CLIMATE CHANGE FACTS

It is important to have your facts straight about climate change and the science behind it. New information is coming out all of the time. Luckily, there are many scientists around the world, including in Canada, who are working hard to understand how the climate is changing, and identify the most effective ways to slow climate change down and transition to a more just, low-carbon future.

This section covers facts about climate change science. Remember, you don’t need to be an expert to be qualified to take action to address the climate crisis. You can learn as you go!

WHAT IS CLIMATE CHANGE?

Though global warming and climate change are often used interchangeably, there is a clear distinction between the two terms.

“Climate change is a long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates. These changes have a broad range of observed effects that are synonymous with the term...

Global warming is the long-term heating of Earth’s climate system observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere” (Climate Kids: What is the Greenhouse Effect?)

Title: The Greenhouse Effect
Source: nasa.gov

Another important term related to climate change is the greenhouse effect, which occurs when gases in the Earth's atmosphere trap the Sun's heat. The Earth is a comfortable place to live because of the greenhouse effect (Climate Kids: What is the Greenhouse Effect?). Naturally occurring greenhouse gases include carbon dioxide, methane, nitrous oxides and even water vapour.

"When I was a kid global warming was something that came up in school as a topic that my teachers told us about. Now that I think about it, global warming was really downplayed and reduced to a topic that could only be mentioned in passing, and not one that needed to be carefully taught and studied. Climate change is a very serious issue and one that needs to be prioritized in schools and in our government’s actions".

- Juaria, TDSB student

WHAT ARE THE CAUSES?

Human activities have caused additional greenhouse gases to be released into the atmosphere. This has caused the earth to warm at a much more rapid rate than what would have occurred naturally. Increased levels of greenhouse gases in the atmosphere pose a threat to our economies, our environment and our lives.

An increased use of fossil fuels is one of the leading causes of climate change. Fossil fuels include coal, oil and natural gas, and are made from animals and plants that have decomposed. When burned, these fossil fuels create energy, but they also release additional greenhouse gases such as carbon dioxide into the atmosphere. Many of the activities we do everyday rely on fossil fuels: driving a gas-powered vehicle, cooking on a stove and heating a building.

Increased livestock farming, fertilizers containing nitrogen and fluorinated gases are also contributors to climate change. Livestock farming releases gases into the atmosphere because cows and sheep produce large amounts of methane when they digest their food. Fertilizers that contain nitrogen produce their own emissions and add to the greenhouse gases that are released. Fluorinated gases are human-made gases that can stay up in the atmosphere for centuries and produce a very strong warming effect that can be up to 23,000 times greater than CO2.

Cutting down forests for lumber or to make space for homes, farms and roads, also contributes to climate change. Trees naturally absorb carbon dioxide, helping to regulate the amount of carbon dioxide that is released into the atmosphere. However, when deforestation occurs all the carbon dioxide that is stored in trees is released into the atmosphere and trees are no longer able to act as carbon sinks, removing carbon dioxide from the atmosphere. (Causes of climate change - Climate Action)

WHAT ARE THE IMPACTS?

Climate change is already impacting most corners of the earth. Globally, average temperatures have risen about 1.5°C already, which may not seem like much, but this change is responsible for an increase in cyclones, droughts, melting of glaciers, sea level rise and other changes we can already observe.

The Intergovernmental Panel on Climate Change (IPCC) is the United Nation’s body for assessing the science related to climate change and they are one of the most reliable sources of information about climate change. The IPCC produces a comprehensive global report every 5-8 years and the next (6th report) will be released in 2022. These reports are the backbone of international climate action and cooperation. While the IPCC reports themselves are very long and technical, the Summary for Policymakers versions are easier to review and understand. One thing to remember about IPCC reports is that by the time they are published, the information may already be out of date. This is because the process of reviewing all of the scientific studies related to climate change takes a long time and involves scientists from all over the world. However, the IPCC’s message is clear: humans are causing climate change and we must take urgent action to avoid catastrophic impacts on humans and the rest of nature. Refer to the resources section below for a list of relevant IPCC reports.

HOW CAN WE RESPOND?

Solutions to climate change can be broadly grouped into two approaches:

Climate change mitigation: reducing greenhouse gas emissions (i.e., shifting away from activities that burn fossil fuels). This approach also includes activities that increase the absorption of CO2 already in the atmosphere (e.g. tree planting, or expanding green spaces).

Climate change adaptation: preparing for and adapting to the impact of climate change, to manage the effect on human society and on natural systems. This can include a very wide range of actions, individual to international in scope, and touching on diverse sectors such as food security, water security, energy security, ecosystem restoration.

Co-benefits of climate action

It is important to note that many climate actions have co-benefits, meaning they help to reduce greenhouse gases (mitigation) and help people and ecosystems become better prepared to deal with current and anticipated climatic changes (adaptation). Some of the most impactful climate actions help to address both climate mitigation and adaptation.

Examples of climate actions with co-benefits include:

Planting trees in cities helps to absorb GHG emissions but also helps keep cities cooler, absorbs runoff during very heavy rains and creates habitat for animals. Additionally, trees make cities more attractive and pleasant places to live, which contributes to our mental health.
Using water more efficiently can ensure a lasting supply, reduce costs, and uses less energy in treatment and transportation
Using energy more efficiently can reduce GHG emissions and also reduces the cost of living or doing business
Burning fewer fossil fuels reduces GHG emissions but also improves air quality and people’s health.
Walking and cycling can help to reduce GHG emissions but also improves health and well-being.
Community food gardens can improve food security and health and reduce the carbon footprints of foods from production, transportation and storage.

Title: Climate Change Mitigation and Adaptation Examples

Source: City of Calgary’s Climate Resilience Strategy

Although climate change can be a scary phenomenon to learn and talk about, it is critical that we take steps now to reduce Toronto’s reliance on fossil fuels and get our greenhouse gas emissions closer to zero:

Big corporations have a huge carbon footprint, and need to be at the front of the transition to clean energy. They use huge amounts of fossil fuels to create, produce and ship their products. Citizens can lobby them and also boycott their products to force them to make this shift.

Governments need to guide the way by making it easier for businesses and citizens to shift away from fossil fuels towards renewable energy and sustainable and equitable ways of living, working, and playing. Citizens can lobby them and vote for candidates who prioritize climate action and ending reliance on fossil fuels.

On a personal level, citizens can limit the amount of fossil fuels used everyday (e.g. using fewer cars, shifting to electricity for cooking and heating homes, and using energy efficient technologies, reducing food waste and eating more local, plant-based foods).

RESOURCES

Climate Change 2014 Synthesis Report Summary for Policymakers: The 5th IPCC report (2014)

Special Report on Climate Change and Land: IPCC Summary for Policymakers (2019)

Special Report on the Ocean and Cryosphere in a Changing Climate: IPCC Summary for Policymakers (2019)

Special Report on Global Warming of 1.5 ºC: IPCC Summary for Policymakers (2018)

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