In 2021, North America witnessed severe heatwaves and searing wildfires in British Columbia, California, and other parts of the west. Lytton, BC recorded a Canadian record high temperature of 49.6˚C on June 30th, before being completely destroyed by wildfire on June 31st. In Ontario, a record-breaking 120 mm of rainfall fell within 48 hours in London in September 2021, causing intense flooding. Collectively, all these events present local evidence of a planet in the grip of weather extremes fueled by rising carbon emissions.
The Canadian Institute for Climate Choices in their Tip of the Iceberg report (2020) found that the combined losses per weather-related disaster soared in just four decades by 1250% – from an average of $8.3 million per event in the 1970s to an average of $112 million between 2010–2019.
As part of the Paris Agreement on climate change, countries committed to keeping global warming well below 2˚C above pre-industrial levels while trying to limit the temperature increase to 1.5˚C. The Intergovernmental Panel on Climate Change (IPCC) examined the difference in impacts between a 1.5˚C and 2˚C temperature increase. Their findings suggest that the world will face severe climate impacts even with 1.5˚C of warming, and the impacts will worsen significantly with a 2˚C rise.
Extreme Precipitation
The IPCC Special Report found that at 2˚C warming, countries like Canada will see an increase in heavy rainfall events compared to 1.5˚C warming. More Canadian municipalities will get impacted by flooding and increased runoff. Recent costs of extreme precipitation and related events for Ontario’s municipalities include – in July 2021, severe thunderstorms and a resultant tornado destroyed 150 homes leading to $75 million in insured damages in Barrie, Ontario. A May 2018 wind and rainstorm in Hamilton & the GTA resulted in losses of over $500m. These events are likely going to multiply if the temperature rises by 2˚C.
Heatwaves
At Earth’s mid-latitudes, the hottest days will be up to 3˚C hotter at 1.5˚C global warming and up to 4˚C warmer at 2˚C warming. Eastern North America will face some of the warmest extreme temperatures. The soaring temperatures seen in British Columbia in the summer of 2021 indicate that huge temperature spikes can occur where they are least expected. This single event led to more than 560 deaths. At warming above 1.5˚C, residents of twice as many cities are likely to become heat stressed, potentially leading to extreme heat exhaustion and death.
Health Impacts
A 2°C increase could also lead to expansion and shifts in the geographic range of vector-borne diseases. The number of people infected with vector-borne diseases is projected to increase. For example, rising temperatures in Canada have led to a range expansion of ticks carrying Lyme disease. In Ontario, 1003 cases of Lyme disease were reported in 2017, which is three times higher than the annual average of 313 cases from 2012 to 2016.
Besides these, there are numerous impacts associated with the rising temperatures that are difficult to quantify including a rise in concentrations of ground-level ozone impacting the health of people, mental health impacts on people due to weather-related disasters, changing precipitation conditions making homes uninhabitable, threatening drinking water supplies and increasing food insecurity to name a few.
Municipalities have influence over roughly 50% of greenhouse gas (GHG) emissions in Canada. Despite constrained resources, now, more than ever, municipalities are working towards stronger climate actions. To limit their greenhouse gas emissions, the City of Edmonton was the first in Canada to create a 135 Mt carbon budget and more municipalities are following the lead. Across Canada, municipalities are adopting Green Development Standards to create cleaner, more cost-effective, and energy-efficient communities in the future. Climate change inclusion needs to occur within various municipal plans for well-rounded decision-making. Sharing successes and lessons learnt with their peers will help municipalities take collaborative and strong climate action.
By, Devanshi Kukadia, Research and Communications Manager