The arctic tundra is a vast, dry, rocky place that is noted for its lack of trees. One important characteristic of the tundra is the permafrost.

• The word permafrost is short-form for the permanently frozen soil, which starts within a meter of the soil surface. In the winter almost all of the soil is frozen.
• In the summer the soil near the surface thaws, but the permafrost at lower depths remain frozen.
• The permafrost limits how far roots of plants can extend down into the soil.
• It also is what prevents trees from growing.
• The ground in the arctic tundra tends to be rocky and the soil has few nutrients.
• This is because the decomposition rates of plants tends to be low.
• Despite the lack of trees, this biome is still considered a major carbon sink as there are large amounts of organic matter found in deposits of peat and humus.
• Peat is decayed sphagnum moss and humus is organic matter.

Distribution

• North of the Arctic Circle and south of the Antarctic Circle are where they are spread.
• Greenland and Antarctica’s ice caps are restricted to the highlands and high latitude regions.
• Antarctica is the world’s largest single ice cap in the southern hemisphere (10,000 feet thick).
• The lowlands — Greenland’s coastal strip, northern Canada and Alaska’s desolate regions, and Eurasia’s Arctic shoreline – all have tundra climates.

Climate

• Due to its northern position, the arctic tundra has a very cold climate.
• Temperatures range from 15.5 °C in summer to -60 °C in winter and mean temperatures are below 0°C for six to 10 months of the year.
• Summers are also much shorter than the winters.
• The northernmost part of this biome receives close to 24 hours of sunlight during parts of the summer.
• And it receives close to 24 hours of darkness during parts of the winter.
• Annual precipitation is around 150 to 250mm a year.
• Most of this precipitation does not evaporate due to the low temperatures.
• Rivers and lakes often form soil tends to be very soggy in the summer.

Natural Vegetation

• Due to the cold climate and short growing season, most vegetation in the tundra tends to be herbaceous.
• Examples of herbaceous plants found there include grasses, mosses such as reindeer moss, liverworts and lichens.
• The few woody plants which live in the tundra, such as dwarf willows, tend to be short and spread across the ground.
• Plants in this biome also tend to go dormant during the long winters.
• This means that they slow down their normal life functions.
• Most of their biomass (mass of their parts) is below ground.

Human Activities

• The tundra’s human activities are mostly limited to the coast.
• A semi-nomadic lifestyle is maintained.
• The Eskimos live in Greenland, northern Canada, and Alaska.
• They reside in little igloos during the winter.
• Fish, seals, walruses, and polar bears supply their sustenance.
• Rifles are being employed to track down animals instead of traditional harpoons.

Significance

• The Tundra plays a significant part in the planet’s temperature management.
• It works as a carbon sink, absorbing carbon dioxide from the atmosphere and assisting in the mitigation of the negative impacts of carbon emissions.

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