Record-breaking hurricanes in the Atlantic; wildfires raging across the West coast and the Mediterranean; killer heatwaves across Europe and Australia; destructive flooding in South Asia. The list goes on and on. It seemed like 2017 had more than its fair share of disastrous weather.
Although no single event can ever be directly linked to climate change, it is becoming more and more clear that rising global temperatures influence the likelihood of dangerously severe patterns of weather. As 2017 is poised to be the third-hottest year on record, the destructive weather patterns of the past year are likely just a sign of things to come.
Before we break for the holidays, we thought we would take a sombre look back at some of the top Canadian weather and climate change stories of 2017.
1. Wildfires in British Columbia
By August, when the fire season usually hits its peak, 2017 had already become British Columbia’s worst fire season in history. In the end, the province set three new wildfire records: the largest total area burned, the largest single fire ever recorded, and the largest number of evacuees. Downwind communities had to content with weeks of endlessly smoky skies that increased health risks and caused widespread evacuations.
Climate change will certainly lead to more wildfires in Canada. Warmer temperatures lead to both drier foliage and a higher risk of lightning, and changing summer precipitation and wind patterns will likely only make things worse. Still, about half of all wildfires are caused, either accidentally or on purpose, by humans – and so there is still much that can be done to lessen future fire risk even in the face of a warming climate.
2. Flooding in southern Quebec
In October 2017 southwest Quebec experienced an entire month’s worth of rain in just under 48 hours, flooding 146 different municipalities and forcing many communities to declare states of emergency. In total, over 2,700 people had to be evacuated from their homes.
Climate models consistently warn that the intensity of rainstorms is expected to increase in the warmer future. This is largely because warmer air can hold more water (for every 1 °C rise in temperature, the atmosphere can hold up to 7% more water vapour). Warmer air is also more unstable, meaning there is a larger potential for more powerful storms capable of severe flash-flooding, hail and damaging winds.
3. Drought hits Saskatchewan
In 2017, much of southern Saskatchewan experienced the driest July in over 130 years of record-keeping; in Regina, less than 2 mm of rain fell that month, far below the usual average of 60 mm. For farmers in the region, the heat and dryness was especially damaging because it followed a rainy spring that had been so wet they’d been unable to properly seed their fields. Just south of the border, the same drought-like conditions in North Dakota, South Dakota and Montana had an economic impact of over one billion US dollars.
Drought is expected to become a much more common and destructive weather pattern in the future. Hotter temperatures lead to higher evaporation rates, worsening the risk of drought-like conditions. And climate models project a tripling or even a quadrupling of the number of +30 °C days across the Prairie provinces by the end of this century.
4. Heat Wave in the Capital
Ottawa experienced a record-setting September heat wave in 2017. On September 25th the temperature climbed to 33.0 °C, but with the humidity it felt more like 40 °C. While some people got outside to enjoy the rare summer-like heat, many children across the region found themselves in very warm, non-air-conditioned buildings for the start of the school year.
Thanks to climate change, Southern Ontario and Quebec are projected to experience a very large increase in hot weather in the near future; the nature of climate change means that temperature extremes are expected to increase much faster than temperature averages. Although hot temperatures may sound nice, people who are sick or do not have access to air conditioning can suffer heat exhaustion and even heat stroke – which can be fatal.
5. Churchill railway destroyed by floods
Churchill, Manitoba, experienced severe flooding in May 2017, and several key sections of a precarious northern rail line – the only land-based transportation route into and out of the town – were washed out. The flood was caused by above average winter snowfall. It is still not known when rail service to Churchill will resume, and without it, food, fuel and building supply costs have skyrocketed.
Climate models project that wetter winters and springs will become the new normal across most of northern Canada. Far too many communities are acutely aware of how expensive proper food and the necessities for life can be in the North, and are watching anxiously as climate change makes hunting and transportation more difficult.
Written by Ryan Smith
Illustration by Bradford Gyselman
The Prairie Climate Centre is committed to making climate change meaningful and relevant to Canadians. We explain and communicate climate change through maps, videos, reports, and web content like this. Sign up for our mailing list to stay informed about our work and about new developments in climate change science and policy. Help us move Canada from climate risk to resilience.