Tundra

A tundra is a special kind of landscape where it is too cold and the growing season is too short for trees to grow tall. It is found in three main places: the Arctic, high mountain areas known as Alpine regions, and around the Antarctic. Because of the cold, the plants that live here are low to the ground, including tiny shrubs, sedges, grasses, mosses, and lichens. In some parts of the tundra, a few scattered trees can be found.

The land where the tundra meets the forest is called the tree line or timberline. The soil in the tundra is rich with nutrients like nitrogen and phosphorus, and it stores a lot of carbon in the form of methane and carbon dioxide because of frozen ground called permafrost. When the Earth gets warmer, this permafrost can melt, releasing these gases into the air. This creates a cycle that makes the planet even warmer, playing an important role in climate change.

Etymology

The word "tundra" comes from a Russian word. It was first used in English in 1824. The Russian word may have come from the Sámi language family, meaning "fell", "elevated wasteland", or "marshy plain". Some sources also say it may have come from the Finnish language.

Arctic

See also: Arctic vegetation

Arctic tundra is in the far north of the Northern Hemisphere, north of the taiga belt. The ground is frozen deep down, called permafrost, so trees can’t grow well. Instead, the land has low plants like moss, lichen, and small shrubs.

The Arctic tundra has two main seasons: a very cold winter and a short, cool summer. In winter, temperatures can drop below -28°C. In summer, they rise to about 12°C. The ground thaws a little, creating marshes and lakes. This area is home to animals like reindeer, Arctic foxes, and snowy owls, and people such as the Sámi who live by herding reindeer.

Antarctic

Antarctic tundra is found in Antarctica and on islands nearby such as South Georgia and the South Sandwich Islands and the Kerguelen Islands. Most of Antarctica is covered by ice fields or cold deserts. But some areas, especially the Antarctic Peninsula, have rocky soil where plants can grow.

Plants in this area include around 300–400 kinds of lichens, 100 mosses, 25 liverworts, and about 700 different algae species. The two flowering plants here are Antarctic hair grass (Deschampsia antarctica) and Antarctic pearlwort (Colobanthus quitensis).

Unlike the Arctic, the Antarctic tundra does not have large land animals. But sea mammals and seabirds like seals and penguins live near the coast. Some small animals such as rabbits and cats were brought by people to nearby islands. The plants and animals are protected by the Antarctic Treaty System.

Alpine

Main article: Alpine tundra

Alpine tundra is a cold, treeless area on mountains around the world. Trees cannot grow here because the air is too cold and the soil is not right for them. Plants like grasses, mosses, and lichens live close to the ground to stay safe from harsh weather.

The temperatures are very cold, and there is only a short time each year when plants can grow. Below a certain height, called the tree line, trees can finally start to grow.

Climatic classification

Tundra climates are very cold. They are part of a special group called ET. This means one month might be warm enough to melt snow, about 0 °C or 32 °F. But no month gets warmer than 10 °C (50 °F).

These cold areas are often near places where trees cannot grow. The weather is always chilly.

Even though these regions may have different amounts of rain or snow, they do not get much. The air is so cold that it holds little moisture. This keeps the ground wet, creating marshes and bogs. The plants and animals there depend more on how warm it gets than on how much rain or snow falls.