Tundra covers a broad band across the top of the Northern Hemisphere, stretches along parts of Antarctica’s coast, and appears on high mountain peaks on every continent. It is one of Earth’s coldest biomes, with temperatures ranging from about −40°C (−40°F) in winter to a brief summer peak around 18°C (64°F), and it receives only 150 to 250 millimeters (6 to 10 inches) of precipitation a year, including melted snow. There are three distinct types of tundra, and each shows up in different parts of the world.
Arctic Tundra: The Northern Belt
The largest and most familiar type is Arctic tundra, which wraps around the top of the globe roughly between 60°N and 75°N latitude. It sits north of the taiga (boreal forest) belt and extends to the edges of permanent ice sheets and polar seas. The countries that contain significant Arctic tundra include Russia, Canada, the United States (Alaska), Greenland (Denmark), Norway, Sweden, Finland, and Iceland.
Russia holds the single largest share. Its northern coast, from the Kola Peninsula east through Siberia to the Bering Strait, contains a vast stretch of treeless, permafrost-covered ground. Canada’s tundra runs across the northern mainland from the Yukon border to Labrador and covers most of the Arctic archipelago, including Baffin Island and Ellesmere Island. In Alaska, the Arctic Coastal Plain alone spans roughly 60,000 square kilometers between latitudes 68°N and 71°N, from the Chukchi Sea coast to the Canadian border.
Scandinavia’s tundra is more limited in area. It appears along the northernmost fringes of Norway, Sweden, and Finland, plus the Norwegian archipelago of Svalbard. Iceland’s interior highlands also qualify, though they sit at a somewhat lower latitude than most Arctic tundra because the island’s maritime climate keeps summer temperatures cool enough to prevent forest growth.
What Lies Beneath: Permafrost
The defining feature beneath Arctic tundra is permafrost, a layer of ground that stays frozen year-round. It can extend to remarkable depths: up to about 683 meters (2,240 feet) in the thickest areas. Only a thin surface layer, called the active layer, thaws each summer. Near Utqiaġvik (Barrow), Alaska, that thawed layer is only about 30 centimeters (12 inches) deep. In warmer tundra zones, the active layer can reach 3 meters (10 feet). This shallow thaw is the only soil available for plant roots, which is why tundra vegetation stays low to the ground: mosses, lichens, grasses, and small shrubs rather than trees.
Antarctic Tundra: The Southern Edge
True tundra also exists in the Southern Hemisphere, though on a much smaller scale. It appears along the Antarctic Peninsula and on sub-Antarctic islands such as South Georgia, the Kerguelen Islands, and the South Sandwich Islands. Most of Antarctica’s interior is too cold and dry to support even tundra vegetation; the biome is limited to coastal margins and lower-elevation areas where temperatures briefly climb above freezing in summer. Mosses and lichens dominate, with only two species of flowering plant native to the continent.
Alpine Tundra: High Mountains Worldwide
Alpine tundra forms above the treeline on mountains, and it appears on every continent except Australia’s mainland (though it exists in the mountains of New Guinea and on Tasmania’s highlands). The key variable is elevation: the closer a mountain range sits to the equator, the higher you have to climb before reaching tundra conditions.
In the Himalayas and the Southern Rocky Mountains of North America, the treeline sits between 3,300 and 3,600 meters. In California’s Sierra Nevada, it falls in the same range. Move farther from the equator and the threshold drops. The Andean steppe of Argentina transitions to alpine tundra at about 1,650 meters. In southern Africa, the Lesotho Plateau hosts alpine tundra starting around 2,300 meters.
This pattern holds because larger mountain masses retain more heat, pushing the treeline higher, while smaller, more isolated peaks lose heat faster and develop tundra at lower elevations. Major mountain ranges with alpine tundra include the Rockies, the Andes, the Alps, the Scandinavian Mountains, the Ural Mountains, the Himalayas, the mountains of central and eastern Africa (such as Mount Kilimanjaro and Mount Kenya), and ranges in New Zealand’s South Island. The plant communities in alpine tundra look similar to Arctic tundra, low-growing grasses, cushion plants, and lichens, but alpine zones tend to support a richer variety of species because they span more diverse climates.
How Climate Is Shifting the Boundaries
Tundra boundaries are not fixed. Satellite data from 2000 to 2019 show that forest lines across the northern high latitudes have shifted northward, with more than 65% of monitored forest edges moving toward the poles as growing-season temperatures rise. In North America, the average forest line moved north by roughly 43 kilometers over that period, closely tracking rising temperatures. In Eurasia, forests are also creeping northward but lagging well behind the pace of warming. The practical result is that the southern edge of Arctic tundra is gradually being replaced by shrubs and eventually trees, while the northern edge remains bounded by ocean and ice.
This shift matters because tundra permafrost stores enormous amounts of carbon. As the biome shrinks, more of that carbon is exposed to thawing and potential release into the atmosphere, which in turn accelerates warming. The tundra you see on a map today covers a smaller area than it did a few decades ago, and current trends suggest it will continue to contract from the south.