Herschel Island (Qikiqtaryuk), Yukon’s Arctic Island

Abstract

Herschel Island (Qikiqtaryuk) is Canada's westernmost arctic island, 3 km north of the Yukon coast. The island is underlain by permafrost, in which near-surface temperature increased by 2--3 {\textdegree}C during the twentieth century. Herschel Island was originally a ridge, with a high point currently 182 m above sea level. The ridge was glacially up-thrust from Herschel Basin, a depression in the continental shelf to the east. The ground materials are coastal sediments excavated from the shelf and glacial till. The island is separated from the mainland by a narrow and shallow strait that is <1600 years old. Herschel Island has been a key place for Inuvialuit subsistence activities for hundreds of years, because it shelters the ocean to the east from moving pack ice, creating landfast ice on its eastern side that is habitat for ringed seals. The sea near the island is productive due to upwelling of nutrient-rich water from the deep ocean. Pauline Cove, the only anchorage on the northern coasts of Alaska and Yukon with protection from moving pack ice, became a principal base for overwintering of the western arctic whaling fleet in 1890--1910. The ground contains extensive sheets of buried glacier ice and other massive ice, visible in the headwalls of large retrogressive thaw slumps. The northern coastal bluffs, fully exposed to the ocean, have erosion rates of up to 3 m/year.