Strange, catastrophic landslides are kicking off across the far north

Researchers have identified two large permafrost detachment slides in Canada’s Northwest Territories, a newly described form of land collapse linked to thawing frozen ground. The events show how wildfire and Arctic warming can trigger abrupt, far-reaching changes to the landscape.

The slides occurred along the Johnson and Redstone rivers in 2017 and 2018, after a 1995 wildfire removed vegetation that had helped keep the permafrost cool. Together they moved about 30 million cubic yards of earth; one stretched three-quarters of a mile and the other two miles, with frozen blocks as long as 650 feet found at the sites.