LONDON — A book about a fire that ravaged a Canadian city and has been called a portent of climate chaos won Britain's leading nonfiction book prize on Thursday.

John Vaillant's Fire Weather: A True Story from a Hotter World was awarded the 50,000 pound ($62,000) Baillie Gifford Prize at a ceremony in London.

The chairperson of the judging panel, Frederick Studemann, said the book tells "a terrifying story," reading "almost like a thriller" with a "deep science backdrop."

He called Fire Weather, which was also a U.S. National Book Award finalist, "an extraordinary and elegantly rendered account of a terrifying climate disaster that engulfed a community and industry, underscoring our toxic relationship with fossil fuels."

Vaillant, based in British Columbia, recounts how a huge wildfire engulfed the oil city of Fort McMurray in 2016. The blaze, which burned for months, drove 90,000 people from their homes, destroyed 2,400 buildings and disrupted work at Alberta's lucrative polluting oil sands.

Vaillant said the lesson he took from the inferno was that "fire is different now, and we've made it different" through human-driven climate change.

He said the day the fire broke out in early May, it was 33 degrees Celsius (91.4 degrees Fahrenheit) in Fort McMurray, which is about 600 miles (1,000 kilometers) south of the Arctic Circle. Humidity was a bone-dry 11%.

"You have to go to Death Valley in July to get 11% humidity," Vaillant told The Associated Press. "Now transpose those conditions to the boreal forest, which is already flammable. To a petroleum town, which is basically built from petroleum products — from the vinyl siding to the tar shingles to the rubber tires to the gas grills. ... So those houses burned like a refinery."

Vaillant said the fire produced radiant heat of 500 Celsius — "hotter than Venus."

Canada has experienced many devastating fires since 2016. The country endured its worst wildfire season on record this year, with blazes destroying huge swaths of northern forest and blanketing much of Canada and the U.S. in haze.

"That has grave implications for our future," Vaillant said. "Canadians are forest people, and the forest is starting to mean something different now. Summer is starting to mean something different now. That's profound, It's like a sci-fi story — when summer became an enemy."

Founded in 1999, the prize recognizes English-language books from any country in current affairs, history, politics, science, sport, travel, biography, autobiography and the arts. It has been credited with bringing an eclectic slate of fact-based books to a wider audience.

Vaillant beat five other finalists including best-selling American author David Grann's seafaring yarn The Wager and physician-writer Siddhartha Mukherjee's The Song of the Cell.

Sponsor Baillie Gifford, an investment firm, has faced protests from environmental groups over its investments in fossil fuel businesses. Last year's prize winner, Katherine Rundell, gave her prize money for Super-Infinite: The Transformations of John Donne to a conservation charity.

The judges said neither the sponsor nor criticism of it influenced their deliberations.

Historian Ruth Scurr, who was on the panel, said she did not feel "compromised" as a judge of the prize.

"I have no qualms at all about being an independent judge on a book prize, and I am personally thrilled that the winner is going to draw attention to this subject," she said.