The Tundra, The Worlds Coldest Biome

The Arctic Tundra is found almost entirely in the Northern Hemisphere, encircling the North Pole and moving south towards the taiga forests. The Arctic Tundra covers about 20% of the worlds surface, spanning across Alaska, the Northern Coast and Islands of Canada, Coastal Greenland, Iceland, Northern Europe, Svalbard, and the Northern Coast of Russia and Siberia. The Arctic Tundra has low levels of sun, and the more northern one goes, the less sunlight the area gets. In the peak of summer, there is sunlight 24 hours a day, which creates a phenomenon called "midnight sun". In the peak of the winter months, the Arctic Tundra experiences complete darkness instead.

The Arctic tundra is very cold most of the year, with its temperatures only raising above 0ºC for the summer season. While these temperatures would usually allow for plants to thrive, in the Arctic Tundra it limits their growth. The temperatures in the Arctic Tundra's summers are between 3ºC and 16ºC, the highest of which occurring usually in July or August. The Arctic Tundra's summers last between 2-4 months depending on where one lives in the biome. In winter on the other hand, which is how the Arctic Tundra stays for an average of 6-10 months, the temperatures range from the average temperature of -28ºC to a whopping -70ºC in its coldest spikes.

The precipitation levels in the Arctic Tundra range from 15-25 cm a year, most of which is snow. Though there is not a lot of precipitation each year, there is still moisture in the soil due to permafrost and lack of evaporation. A lot of ponds are formed through melting snow and soil in the summer months, and as these ponds form, freeze, and thaw, they make way for small groups of vegetation.

The soil of the Arctic Tundra is split into two layers, the active layer and the permafrost. The active layer of soil is 25-100 cm deep and it is the part of the soil that allows for life. It melts in the summer months to allow plant growth, but with relative difficulty as the soil is mostly water-logged and cannot provide a lot of nutrients through decomposition. The permafrost however doesn't fully melt, even in the summer season and makes up the deeper layer of the soil at about 100 cm to 450 meters deep underground. Permafrost thwarts the growth of trees as it is frozen solid, it also creates the ponds and water formations across the Arctic Tundra when its top layer melts. It also stores a lot of carbon, methane, and other natural gasses, which makes it a concern for the warming climate.

The Arctic Tundra is home to about 1700-2000 plant species, and 48 land mammals. The rest of the animal population are migrants that only stay for the summer and leave before winter. Bird migrants include: Snow Geese, Barnacle Geese, Peregrine Falcons, Arctic Terns and many others. These birds are monogamous to survive and are able to travel very long distances. Mammals that migrate to the Arctic Tundra are few and far between, but the Caribou are one of them, coming in massive herds. Some species of Caribou actually stay in the Arctic Tundra all year round. Certain species of fungi can even classify as migrants, showing at only certain times of the year.

The three major vegetation zones in the Arctic Tundra are the polar deserts, tundra, and northern boreal forests. Temperature rise will cause heavy vegetation shifts, causing denser and more plentiful vegetation than the biome is used to. This will cause the forest to push up onto the tundra, and the tundra to push up onto the polar deserts. Along with these shifts, the rising sea levels will shrink the Arctic Tundras area to the lowest it has been in 21,000 years. This will reduce land area for grazing animals and birds to breed and live. With the decline of land, many species are projected to go extinct with a sharp decline following.

Many of the species in the Alpine Tundra have unique abilities to withstand the cold that leave them vulnerable to other encroaching species as the temperatures rise. This encroachment is detrimental as many of these species cannot adapt properly to the new population. As temperatures rise, species from the south will move northward and the northward species will be pushed up against the Arctic Ocean, with nowhere to go. Such displacement has already occurred among some bird, fish, and butterfly species, with specific species like seabirds, mosses and lichens predicted to be victims to this. This is troubling as the diversity of lichen and mosses is unparalleled to anywhere else in the world, and this diverse assortment is at risk of being lost forever.

As species push further south, the number of species is projected to increase in the Arctic Tundra, but this migration will cause ecosystems to shift, and these ecosystems do not move intact. Each organism of the ecosystem will move in response to their own sensitivities, life span, mobility, moisture, and the availability of select soils. Animals can move more readily than plants, and certain animals have advantages in terms of mobility. This separation and scattering of ecosystems to different parts of the Tundra will result in the formation of new ecosystems and communities, and this scattering and reformation will have unknown consequences.

The Alpine Tundra is Tundra found in high altitude, mountainous regions. The Alpine Tundra is found mostly away from the pole regions and they take their name from the Swiss Alps. The Alpine Tundra has higher average annual temperatures, more precipitation, and like the Arctic, it has little to no trees. The Alpine Tundra are found in the Scottish Highland, The Himalayas, The Rift Mountains of Africa, the Tibetan Plateau, the American Cordillera, and the Carpathian Mountains.

The Alpine Tundra can be found on high mountain ridges and slopes above the treeline. The treeline varies on where the Alpine Tundra is found, the higher the treeline the warmer the location. The landscape varies as well, from rocky mountain peaks with snow, talus slopes and cliffs, and flat topography with gentle slopes. The geographical distribution of the Alpine Tundra is due to three things, high latitude, high altitude, and temperatures below 25ºC. The low temperatures are important in the biome as they prevent trees from growing. They also lack water, which causes low plant growth. The area is also home to high winds that influence the direction of the vegetation in certain areas.

The temperatures in the Alpine Tundra range from 9ºC to -12ºC. The highest temperatures are in July, the lowest in December and January. The average annual temperatures are the same in polar Alpine regions. Near the equator there are more extreme temperature variations, like on Mt. Kenya, where the average temperature for a day can be 15ºC and lower to -5ºC ion the the same day.

In the Alpine regions when the warm air is pushed up from lowland regions it becomes cooler and condenses as clouds. When that happens the clouds are more susceptible to rain or snow. The higher the altitude in the Alpine Tundra, the higher the precipitation, usually as snow. Along with high precipitation the biome has low air pressure. The altitudes above 18,000 feet have oxygen levels below half that of regions found at sea level, so most animals cannot survive at those levels. though, some birds and cold-blooded invertebrates can survive at those altitudes.

Plant life in the Alpine Tundras is based on altitude, soil, and vegetation zones. The animal life is based on altitude and the specific Alpine region.

As temperatures rise, Alpine areas across the globe will experience a significant rise in the treeline, and this rise over time can swallow up the Alpine Tundra whole. Due to the permafrost thawing, it will allow the treeline to creep upwards encroaching on the land and drive many Alpine species to extinction. Many of these poor animals have poor adaptation due to the unique topography of the area. In a 3º warming scenario the Alpine Tundra could shrink up to 84%, the loss only lowering to 48% if we get the temperature down to 1.5º. Europe has 87,000 km2 of Alpine Tundra which is split into three regions, the Alps, Pyrenees, and the Scandes. With a 3º warming scenario, the Pyrenees is projected to completely disappear, The Scandes by 87%, and the Alps by 75%. With a lower warming scenario the loss is still heavy but significantly less.

Approximately 20% of the current Alpine region is protected by the EU as Natura 2000 sites. Almost every Alpine Tundra Natura 2000 region (210 regions) is projected to shrink significantly. In a 1.5º warming scenario these sites could shrink anywhere between 36 and 73%, the highest in the Pyrenees. In the worst scenario however, all sites could shrink by over 74%.

The treeline in the three areas described above could rise over 600m in the worst cases, causing the shrinkage projected. Along with heavy shrinkage, the effect on both the biosphere and hydrosphere could be devastating. The water melting from the Alpine glaciers could alter downstream water supply and add unwanted debris and sediment to the water. The decline of the cold mountain habitat could drive many Alpine plant species to extinction, and would allow for a boom in warm mountain species, which could overtake the remaining cold mountain species. Winter sports domain would be restricted and potentially lost, and the areas may lose migration all together.