Permafrost thaw and 'shrubification' have tipped Alaska's North Slope into a wildfire regime not seen for 3,000 years

Long road along tundra with mountains in background and cloudy sky.

Wildfires on Alaska's North Slope are more frequent and more severe now than they have been at any point over the past 3,000 years, research suggests.

The findings are based on satellite data and ancient charcoal fragments. The research team says the increase in blazes, driven by permafrost thaw and tundra "shrubification," constitutes a new wildfire regime that will likely intensify as global temperatures continue to rise.