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Different Subarctic Landforms

Subarctic ecosystems are those lying directly south of the Arctic Circle, providing a transition zone between temperate and Arctic latitudes. They are only found in the Northern Hemisphere, as the Southern Hemisphere does not have landmasses in the high latitudes large enough to induce the cold, dry continental climate found in northern Eurasia and North America. Part of the region's character stems from its defining landforms and landscapes.

Canadian Shield
- In geology, a shield is the exposed portion of a structure called a craton, which is the old, crystalline, geologically stable heart of a continental landmass. Much of the North American subarctic lies within the bounds of the Canadian Shield, a massive area of relatively low-relief underlain by Precambrian basement rock. Portions of the Canadian Shield extend southward into the U.S. in the Superior Upland of the Upper Midwest and the Adirondack Mountains of upstate New York. In the Canadian subarctic, the shield supports vast acreage of boreal forest, typically strung with lakes and glacier-smoothed rock, grading into tundra to the north.
Mountains
- Subarctic mountains form the region's most rugged topography.
  
  Notable mountain ranges provide the most rugged topography in the subarctic. The Brooks Range in northern Alaska is a wild highland chain of sharp peaks and deep gorges, roamed by grizzly bears, Dall sheep, caribou, gray wolves and wolverine. It separates the subarctic Alaskan interior from the coastal tundras of the North Slope dropping to the Arctic Ocean. Two of its notable peaks form the so-called "Gates of the Arctic," a landmark that today gives its name to a large national park. Other examples include Siberia's Verkhoyansk and Chersky ranges.
Rivers and Lakes
- Subarctic rivers may run impressively high when swollen with snowmelt. In winter, many are capped with thick ice; the breakup of the ice is a major event for the region's human population, as it once again permits transportation by boat along the waterways. Some of North America's largest rivers flow in the subarctic, including the Mackenzie in Canada, which flows from the Great Slave Lake to the Beaufort Sea; and the Yukon, which rises in British Columbia, flows through the Yukon Territory and then nearly bisects Alaska as it crosses its interior to reach the Bering Sea. The Canadian subarctic harbors several huge lakes, including the Great Bear and Great Slave lakes of the Northwest Territories, their basins enlarged by glaciers during the Pleistocene.
Taiga
- The taiga, or boreal forest, covers huge swaths of northern Eurasia and North America.
  
  While not a landform proper, the great boreal forests that cover much of the subarctic certainly constitute one of the region's defining ecological landscapes. These vast stunted woods of spruce, fir, birch, poplar and other hardy trees constitute the largest forest ecosystem in the world. As such they contribute enormously to global carbon sequestration, and provide habitat refuges for large mammals like woodland caribou, brown bears, lynx and moose.

Nature