Worsening wildfires, B.C.-like flooding part of 'new reality' driven by climate change: study

EDMONTON -

Eight of the worst wildfire weather years the world has ever recorded happened in the past decade, a new study from Canadian scientists revealed Thursday.

The research team believes lower humidity and higher temperatures will continue to contribute to more burning, which can also make flooding worse in and around recent fire zones.

“Extreme conditions drive the world’s fire activity,” wildfire expert Michael Flannigan was quoted in a news release from the University of Alberta.

“It's not a big surprise, but with climate change, we expect warmer conditions to continue and this trend to continue, expand and get worse.”

Flannigan conducted the study with help from Natural Resources Canada scientist Piyush Jain and the U of A's Sean Coogan.

The study examined "extreme fire weather trends from 1979 to 2020 using common fire weather indexes that provide estimates for fire intensity and rate of fire spread, as well as changes in vapour pressure, or humidity."

The team concluded that decreasing relative humidity was a driver in more than 75 per cent of increases in fire intensity and spread and increasing temperature was a driver in 40 per cent of significant trends.

The team also found that B.C. recorded three of five of their worst fire years ever in 2017, 2018 and 2021.

Flannigan said this is a factor in making flooding there worse.

“When you remove the vegetation, the rain is not being intercepted by the trees, the roots aren't picking up the moisture, there is nothing to give the soil stability — you're much more likely to see land and mudslides in burnt areas," he said.

“This has been documented in California for years.”

The study was published in Nature Climate Change, a monthly academic journal that focuses on climate change.