B.C. heat waves were made more likely by human-caused climate change, says report

Heat waves that blanketed British Columbia in August and early September were made much more likely by human-caused climate change.

That’s according to a report released Wednesday by Environment and Climate Change Canada (ECCC).

Canadian climate scientists analyzed 10 of the hottest heat waves across the country in July and August, using a system that monitors extreme heat and cold events. The system applies climate models to compare current conditions with the pre-industrial climate of the 1800s.

Researchers found nine out of the 10 heat waves were made much more likely because of climate change. Human influence made the events at least two to 10 times more likely to occur, the report said.

The list included the heat wave that scorched southern B.C. from Aug. 23 to Sept.7, which saw peak daily highs of 27 C.

Also on the list is the northern B.C. heat wave, which began at the same time but lasted through to Sept 9, with highs of 27.5 C.

During both events, peak temperatures were about 10 degrees above normal, the report said.

ECCC said one heat wave that hit Atlantic Canada from Aug. 7 to 14 stands out as being at least 10 times more likely to occur due to human-caused climate change. 

It also noted prolonged heat waves and longer fire seasons are major contributors to more frequent and intense wildfires across Canada. 

This year’s wildfire season, along with 2024 and 2023, are among the top 10 on record in terms of area burned.

About 8,790 square kilometres of land has burned so far this wildfire season, according to the B.C. Wildfire Service. Of the 1,274 wildfires across the province this year have been caused by lightning, but more than 500 are believed to be human-caused.