Taking Action on Climate Change in Toronto Region
On This Page We Explore:
1. How climate change is affecting our planet. READ MORE.
2. What impacts we can expect within Toronto and Region. READ MORE.
3. What Toronto and Region Conservation Authority (TRCA) is doing to combat climate change. READ MORE.
4. What you can do to take action. READ MORE.
5. Resources you can use to learn more. READ MORE.
“Every action matters. Every bit of warming matters. Every year matters. Every choice matters.”
— Intergovernmental Panel on Climate Change (IPCC), 2022
Human-caused climate change is putting people, ecosystems, and the economy at risk. Record-breaking temperatures and extreme weather are becoming the new norm, leading to irreversible impacts as natural and human systems are pushed beyond their ability to adapt.
The Intergovernmental Panel on Climate Change’s 2021-22 Sixth Assessment Report highlights the devastating consequences resulting from higher levels of global warming. The IPCC is the United Nations body responsible for assessing the science related to climate change, its impacts and potential future risks, and possible response options.
The scientific community has issued a “code red for humanity”. The time for action is now: We must work together to limit warming to below 2°C, and ideally to 1.5°C, by cutting global greenhouse gas (GHG) emissions in half by 2030, and reaching net-zero by 2050.
1. HOW CLIMATE CHANGE IS AFFECTING OUR PLANET
Based on an assessment of 14,000 scientific publications, the evidence shows changes in every corner of the world. A few examples:
2. HOW CLIMATE CHANGE IMPACTS OUR REGION
These changes are being felt locally in TRCA’s jurisdiction – especially extreme heat and flooding. These impacts will worsen if greenhouse gas emissions continue to climb, leading to higher levels of global warming.
TEMPERATURE
In this temperature stripes banner, 175 years of temperature data captured in the Toronto region, from 1849 (left) to 2023 (right). Each bar shows the difference in annual average temperature for each year compared to the average temperature over the 20th century (1901-2000). Warmer than average years are represented by red stripes and cooler years are represented by blue stripes. The darker the stripe colour, the greater the difference from the 20th century average.
Increased global surface temperature by the end of the century, compared to the pre-industrial period (1850–1900). Likely ranges:
- 2.1°C to 3.5°C warmer under the intermediate greenhouse gas (GHG) emissions scenario
- 3.3°C to 5.7°C warmer under the very high greenhouse gas (GHG) emissions scenario
Temperatures are also projected to increase by the end of the century:
- Mean annual temperatures may increase from 7.3°C (1971-2000) to a projected range of 9.8°C to 15.8°C under the high emissions scenario.
- Temperatures are projected to increase across all seasons throughout the year.
We expect that higher temperatures will lead to:
- More extreme heat days
- Earlier snowmelt
- Longer growing season, which may see an increased risk of pests and diseases affecting plants and agricultural crops
- Higher potential for flooding and erosion as warmer air holds more water to produce storms
PRECIPITATION
In this precipitation stripes banner, we show 175 years of precipitation data captured in the Toronto region, from 1849 (left) to 2023 (right). Each bar shows the difference in average annual total precipitation for each year compared to the average precipitation over the 20th century (1901-2000). Wetter than average conditions are represented by green stripes and drier than average conditions are represented by brown stripes. The darker the stripe colour, the greater the difference from the 20th century average.
Increases in global average precipitation will result in:
- Altered water cycle, as rates of change in average precipitation and stormwater runoff increase with global warming
- Substantial regional and seasonal differences in rain and snow as wet regions generally get wetter and dry regions generally get drier
Precipitation is expected to increase in the Toronto region by the end of the century:
- Total annual precipitation may increase from 986 mm (1971-2000) a projected range of 1,015 to 1,292 mm under the high emissions scenario
- More frequent and intense storms are expected to occur with one-day maximum precipitation increasing from 29.4 mm (1971-2000) to 47 to 59.5 mm in a day under the high emissions scenario
We expect that higher precipitation will lead to:
- An increase in hazardous conditions caused by extreme precipitation, placing people, property, and infrastructure at risk
- Adverse effects on water quality and aquatic ecosystem health
- An increase in Lyme Disease and other vector-borne diseases
HOT AND COLD EXTREMES
Hot and cold extremes are expected to continually change with global warming:
- Hot extremes are expected to increase in frequency and intensity, while extreme cold is expected to decrease.
- Extreme heat events that used to have a one in 10 chance of occurring each year are expected to be 8.3 to 9.6 times more likely to occur under the very high emissions scenario.
Hot and cold extremes in our region are projected to change in response to global warming:
- Number of extreme heat days above 30°C and 35°C are expected to increase from around 11 days and 1 day (1971-2000), respectively, to 52 days and 14 days, respectively, under a high emissions scenario.
- Number of days below -20°C is expected to decrease from around 10 days (1971-2000) to nearly zero days to 3 days, under a high emissions scenario.
An increase in extreme heat days will:
- Further increase the demand for energy-intensive cooling, which may place a strain on our electrical capacity and cause power outages during summer months
- Increase heat stroke and heat-related respiratory diseases that can affect our most vulnerable residents, including children, seniors, and those with pre-existing health conditions
Visit TRCA’s Watershed Reporting Hub to view climate projections in the Toronto region.
Ecosystem Changes in Toronto and Region
Climate change has now altered marine, terrestrial, and freshwater ecosystems worldwide. Many ecosystems and species are unable to adapt to these rapid changes. Here are a few examples of ecosystem changes TRCA has observed in the Toronto region:
3. WHAT IS TRCA DOING TO COMBAT CLIMATE CHANGE?
TRCA collaborates with practitioners across various municipalities and other conservation authorities to deliver programs and initiatives geared towards the following:
- Climate Change in the Great Lakes – Video
- Durham Region – Climate Trends
- Durham Region – Climate Impacts
- Guide to Conducting a Climate Change Analysis: Lessons Learned from Durham Region (2021)
- The State of Climate Modeling in the Great Lakes Basin (2020)
- Scan of International Climate Information Platforms (2018)
- Climate Trends and Future Projections in the Region of Peel (2016)
- Historical and Future Climate Trends in York Region (2016)
- Nature-Based Climate Solutions (NBCS) Siting Tool: Phase 1 Pilot Study Report (2022)
- Integrating Climate Change into Durham’s Policies and Plans (2018)
- Natural Systems Vulnerability to Climate Change in Peel Region (2017)
- Climate Change Effects on Agricultural Production in the Region of Peel (2016)
- Climate Change Vulnerabilities of Community Services and Assets in the Region of Peel: A Case Study in Port Credit (2016)
- Assessing and Mitigating Municipal Climate Risks and Vulnerabilities in York Region, Ontario (2016)
- Ontario Climate Consortium Proceedings (2013-2018)
Municipal Climate Strategies and Action Plans
Municipalities across the region have developed strategies and action plans for climate change adaptation and mitigation in their communities. These include:
| City of Toronto: | Resilience Strategy |
| TransformTO | |
| Region of Peel: | Climate Change Master Plan |
| Durham Region: | Durham Community Climate Adaptation Plan |
| York Region: | Climate Change Action Plan |
4. WHAT YOU CAN DO TO TAKE ACTION
Climate Change in Your Community Factsheet
This TRCA resource spotlights the local impacts of climate change and suggests a variety of actions you can take in your own community – from stormwater landscaping projects, to reducing household waste, to choosing more sustainable forms of transportation.
Climate Action Calendar
VISIT THE TRCA CALENDAR FOR MORE COMMUNITY EVENTS
5. MORE RESOURCES
IPCC Working Group Reports
QUESTIONS?
Please contact TRCA Watershed Planning and Ecosystem Science:
wpes@trca.ca