tundra
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CG: n

CT: The tundra is the coldest of the biomes. It also receives low amounts of precipitation, making the tundra similar to a desert. Tundra is found in the regions just below the ice caps of the Arctic, extending across North America, to Europe, and Siberia in Asia. Much of Alaska and about half of Canada are in the tundra biome. Tundra is also found at the tops of very high mountains elsewhere in the world. Temperatures are frequently extremely cold, but can get warm in the summers.

Tundra winters are long, dark, and cold, with mean temperatures below 0°C for six to 10 months of the year. The temperatures are so cold that there is a layer of permanently frozen ground below the surface, called permafrost. This permafrost is a defining characteristic of the tundra biome. In the tundra summers, the top layer of soil thaws only a few inches down, providing a growing surface for the roots of vegetation.

Precipitation in the tundra totals 150 to 250 mm a year, including melted snow. That’s less than most of the world’s greatest deserts! Still, the tundra is usually a wet place because the low temperatures cause evaporation of water to be slow. Much of the arctic has rain and fog in the summers, and water gathers in bogs and ponds.

Vegetation in the tundra has adapted to the cold and the short growing season. Mosses, sedges, and lichens are common, while few trees grow in the tundra. The trees that do manage to grow stay close to the ground so they are insulated by snow during the cold winters.

S: NASA – https://earthobservatory.nasa.gov/biome/biotundra.php (last access: 24 April 2025)

N: 1. nearly treeless Arctic steppe, 1841, from Russian tundra, from Lappish (Finno-Ugric) tundar, said to mean “elevated wasteland, high-topped hill,” or “a marshy plain.”

2. tundra, a major zone of treeless level or rolling ground found in cold regions, mostly north of the Arctic Circle (Arctic tundra) or above the timberline on high mountains (alpine tundra). Tundra is known for large stretches of bare ground and rock and for patchy mantles of low vegetation such as mosses, lichens, herbs, and small shrubs. This surface supports a meagre but unique variety of animals. The Finns called their treeless northern reaches the tunturi, but the concept of a vast frozen plain as a special ecological realm called tundra was developed by the Russians.

  • One constant factor shaping the tundra is alternate freezing and thawing of the ground. Along with the factors mentioned above, this freeze-thaw cycle sets the tundra apart from two ecosystems frequently found adjacent to it—the icy polar barrens on the one hand and the evergreen taiga on the other. Permafrost—perennially frozen ground—is a significant feature of the Arctic tundra; however, it does not typically occur in alpine regions.

3. Distribution

  • The global extent of the tundra biome is considerable, accounting for roughly 10 percent of Earth’s surface. The southern limit of Arctic tundra follows the northern edge of the coniferous forest belt. In North America this line lies above latitude 60° N, while in Eurasia most of it occurs north of 70° N—except in eastern Siberia, where it extends southward to 60° N in Kamchatka. The northward bulge of forest in Eurasia is a result of the warmer summers that occur over that large contiguous landmass.

  • Alpine tundra covers approximately 3 percent of Earth’s land surface, and it is mostly found in the Northern Hemisphere. This habitat can be found in mountainous areas worldwide, occurring at high elevations where temperatures are too low and winds are too strong for the growth of trees. The average elevation where alpine tundra occurs is generally higher near the Equator than at the poles.

  • Because nearly all of Antarctica is covered with ice, it lacks a well-developed tundra, though lichens, mosses, and at least three species of flowering plants occur in more favourable habitats there.

4. Biogeography; Polar Geography; Ecosystems: tundra, barren lands (obsolete), barrens (obsolete).

  • A treeless area between the icecap and the treeline, having a permanently frozen subsoil and supporting low-growing vegetation such as lichens, mosses, and stunted shrubs.
  • barren lands: A term that was once used to describe the tundra of northern Canada, a region characterized by sparse vegetation, a harsh climate, and permafrost.
  • Tundra is called barrens colloquially because it is bare of trees.
  • barrens; barren lands: terms rarely used in the singular (barren; barren land).

5. Cultural Interrelation: We can mention the documentary The Tundra Book: A Tale of Vukvukai, the Little Rock (2011) written and directed by Aleksei Vakhrushev.

S: 1. Etymonline – https://www.etymonline.com/search?q=tundra (last access: 24 April 2025). 2 & 3. EncBrit – https://www.britannica.com/science/tundra (last access: 24 April 2025). 4. TERMIUM PLUS (last access: 24 April 2025). 5. IMDb – https://www.imdb.com/title/tt2137550/ (last access: 24 April 2025).

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CR: biome, canid, ecology, forest, jungle, merlin, prairie, savanna, silviculture, taiga, tropical rainforest.