The arctic tundra is the coldest of all the biomes, with an annual average temperature of less than five °C and precipitation (mainly in snow) of less than 100 mm per year. The tundra is home to a unique group of plants and animals that evolved in this harsh climate. Tundra also has an abundance of rivers, lakes, and wetlands. The tundra biome has the largest area of any biome on Earth and covers about 14% of the land on Earth.
The arctic tundra generally occupies the colder regions north of tree line, but technically it can be found anywhere on Earth where there is permanent ice and snow. One aspect that makes the tundra interesting is that it is physically one continuous habitat with just different ecosystems within its boundaries in some regions of Antarctica because they are near enough to South America for summer melting to occur.
The tundra is primarily located above the tree line in the Northern Hemisphere, but at some points, you can find tundra near the tree line. The tundra biome lacks trees and shrubs and is dominated by grasses and low-growing plants. The permafrost is generally absent due to a lack of snowfall. Because of this, soils are frozen for much of the year.
The water in extreme tundra is evident due to the air being so dry that it does not freeze onto surfaces. Thus, ponds and lakes (possible sites for lakeside dwellings) are often relatively shallow as water cannot accumulate on bottom surfaces or freeze into ice or snow. The water of the tundra is also generally very cold, often colder than the air in winter.
The tundra biome has the least amount of biodiversity of any biome. The largest land carnivore on Earth, this bear dines on fish, seals, and other animals found near the sea ice. The polar blubber fat keeps it warm even in temperatures as low as -50 degrees Celsius (-58 degrees Fahrenheit).
The climate of the tundra:
The tundra’s low precipitation and extremely high latitude cause a climate where temperature fluctuations are not extremely large. The temperature ranges between -35 degrees Celsius and 35 degrees Celsius, with the majority of this variation occurring during the short summer season.
Daily fluctuations in temperature are generally small, usually less than 20 degrees Celsius, but can be as much as 30 degrees Celsius in some regions due to the high latitude. Precipitation is poorly distributed throughout the year, with most of it occurring during warmer months (May to August) when temperatures are above freezing. During winter months, there may be little or no precipitation at all.
Precipitation amounts vary widely across the tundra biome, with some areas receiving more than 3900 mm per year. The wind is expected in the tundra, generally with winds blowing from the North throughout most of the year. The weather patterns on Earth are primarily influenced by the winds moving over it, and these winds typically originate from land to sea (for example, trade winds). This pattern is reversed in the tundra biome due to its high latitude and proximity to Arctic regions with no large landmasses.
Plants of the Tundra:
The arctic tundra is home to only a few species of plants, but these are some of the hardest on Earth. Mosses and lichens dominate much of the area due to their ability to grow in adverse soil conditions.
Location of the Tundra:
Tundra is located throughout much of northern North America and Eurasia. There are a few small tundra regions in the tropics, but the majority of the tundra is located above the tree line in both hemispheres.
The tundra biome extends into Antarctica, Greenland, Iceland, and northern Scandinavia. With its low annual precipitation and high latitude, it only makes sense that a large portion of the world’s tundra is located in North America near the Arctic Circle. Most of Europe also has sizable portions of tundra due to its geographical location on Earth and proximity to North America.
The temperature of the tundra:
The temperature of the arctic tundra can vary significantly between seasons. For example, the winter is freezing due to the low temperatures, but warming from solar radiation is often strong during the summer months. These large fluctuations in temperature are common throughout tundra regions due to the high latitude, low annual precipitation (and thus evaporation), and lack of snow cover during the winter.
Precipitation of the Tundra:
The arctic tundra has meager annual precipitation due to its high latitude but receives snowfall during winter. The amount of precipitation differs wildly across the tundra, with some areas receiving over 7200 mm per year and others receiving as little as 250 mm. As a result, the tundra biome is often a frozen landscape devoid of vegetation; however, some plants can thrive in this environment.
The ground is rarely frozen due to the lack of snowfall. Instead, the ground surface contains permafrost. The temperature around permafrost remains cold enough to prevent ice from forming, and thus plant life cannot survive on or near it. Permafrost is present at low elevations on the tundra and generally rises as you go higher into the mountains. Still, some regions of the tundra have no permafrost due to their high latitude and elevation.
Animals of the Tundra:
Few animals live in the tundra biome; however, the ones that do live there are very successful. Due to the harsh winters, the tundra predators are active hunters and must work hard to find food. The bears, foxes, and weasels of the tundra are some of the most well-known carnivores and prey on animals such as lemmings and other small rodents. Those same small mammals make up much of the herbivore’s diet. Many species in this region also rely on aquatic resources, such as fish, during warmer seasons due to their short growing periods.
Land Animals:
Several land animals live in the tundra biome. The tundra predators are almost exclusively mammals, the largest being polar bears. They mostly hunt fish but also eat other small animals they can catch and scavenge from carcasses. Polar bears have a king-of-the-mountain hunting strategy. Neighboring polar bear groups will cooperate by chasing prey into each other’s territories, causing the prey to be spread out across large areas. Polar bears are not just carnivores; they can be very social and family oriented.
Plant-eating Animals (Herbivores):
The herbivores in the arctic tundra biome are primarily animals that can withstand low temperatures and live on the land. Some small carnivores are known for their plant-eating habits, such as weasels and foxes, but they do not make up a large part of these animals’ diets. Instead, caribou, musk oxen, reindeer, and other species of deer are the most common meat sources for these herbivores.
Plant-eating Animals (Carnivores):
Most carnivores in the tundra have to rely on plants and small animals to survive during winter. Only one known carnivore survives solely on plants: the arctic fox.
