The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of hemiboreal regions and covering much of Alaska, Canada, Iceland, the north of Fennoscandia, Northwestern Russia, Siberia, and the Cairngorms.

Subarctic or boreal climates are the source regions for the cold air that affects temperate latitudes to the south in winter. These climates represent Köppen climate classification Dfc, Dwc, Dsc, Dfd, Dwd and Dsd.

Sub-Arctic regions, previously considered one of the largest pristine ecosystems in the world, are being subjected to increasing pressure from mining and smelting activities. The minerals industry has contributed significantly to environmental damage and deterioration in the Russian sub-Arctic.

Fewer studies have focused on the northward expansion of upper trophic level (UTL) subarctic species. We provide an overview of changes in the temporal and spatial distributions of subarctic fish, birds, and cetaceans, with a focus on the Pacific Arctic Region.

Earth's arctic and subarctic regions are extremely cold, icy areas of land and sea that receive almost no sunlight during their long, dark winters. Temperatures rarely rise above freezing. This is true even during summer in the "land of the midnight sun."