Many of the town’s 650 inhabitants live on permafrost – ground that remains at sub-zero degrees Celsius for two or more consecutive years. Historically, permafrost has provided a solid foundation for buildings and infrastructure in the Arctic. But as the temperature has warmed, the ground has become less capable of supporting Qaanaaq’s homes, which can become dangerous to inhabit.

Other Arctic towns are built in permafrost areas, too. But they’re built on rock. Established in the 1950s before climate change was a consideration, Qaanaaq, meanwhile, is the only town in Greenland built on finer material: clay, silt and sand. "Unlike rock, these sediments contain water, which poses a major challenge," says the University of Copenhagen's Sebastian Zastruzny, who has been studying permafrost in the region for several years. "When the ground freezes and then thaws, it moves up and down – causing houses and infrastructure to sink, slide and collapse."