Canada’s extreme wildfire season offers a glimpse of new risks in a warmer, drier future

The blanket of wildfire smoke that spread across much of the US and Canada in 2023 was a wake-up call and showed what climate change could feel like for millions of people in the near future. However, apocalyptic orange skies and levels of air pollution forcing people indoors only tell part of the story.

As global temperatures rise, fires are also spreading further north and into the Arctic. These fires aren’t just burning in trees and grasses. New research into the exceptional Arctic fire seasons of 2019 and 2020 suggests that fires are also spreading underground.

These underground fires ...