In the Arctic, at the end of the summer, the polar cold sets in In the Arctic, at the end of the summer, the polar cold sets in and ice-crystals appear on the surface of the ocean: the ice pack forms and can reach several meters thick in the middle of winter. It stretches across part of the mainland. As it moves with the ocean swell, it can break in some places creating water channels. In Nunavut, the Inuit territory of northern Canada, the Explorers team traveled through this ice pack and its unique ecosystem.