How Climate Change Impacts the Tundra Biome Delicate Balance
The Tundra biome has long been considered the largest natural carbon reservoir, but global warming threatens all that. Being the coldest of all biomes, Tundra has permafrost as its defining characteristic, significantly slowing down the decomposition of organic matter.
However, with the increasing global temperatures, the permafrost is thawing at an alarming rate, exposing the vast amounts of carbon stored under it. It is estimated that the methane and carbon dioxide released from the melting permafrost could surpass the annual global anthropogenic emission of carbon dioxide alone.
Therefore, there’s an urgent need for climate action to preserve these fragile habitats, as their health and stability are crucial to the species that inhabit them, the indigenous communities that rely on them, and the global climate and system at large.
The Tundra Biome Characteristics
The permanently frozen (permafrost) ground below the surface is one characteristic that defines the Tundra biome. The freezing weather is contributed to by the biome’s geographical location, which is the northernmost and nearest to the North Pole.
The Tundra covers vast land north of the Arctic Circle up to the polar ice cap. It also extends across North America, Europe, and Siberia, covering approximately 11.5 million km2. In fact, much of Alaska and about half of Canada are in the Tundra biome.
The weather here is brutal, characterized by frigid winters that could last up to 10 months and pretty short and relatively cool summers. The Tundra temperature ranges between -340C to -60C. The annual precipitation is also meager, similar to what you’d get in a desert.
The result is a dry, frozen, and rocky plain, which the Finnish call the “Tunturi,” where the term “Tundra” emanates. The Tundra permafrost starts within a meter of the soil’s surface, slowing the breakdown of organic matter and making the ground rocky and lacking nutrients.
As a result, large amounts of organic matter are found in deposits of humus and peat.
The highly concentrated permafrost makes it hard for vegetation to extend its roots down the soil, but the Tundra biome remains a significant carbon sink despite the lack of trees.
Alpine Tundra vs. Arctic Tundra Biome
The Arctic tundra is located in the northern hemisphere, encircling the North Pole and extending south to the Taiga belt, while the Alpine tundra is found in high mountain regions worldwide.
While both Tundra subtypes experience cold, harsh climates and low vegetation, the Alpine tundra has no permafrost, and the soil is well-drained to support the growth of a few plants. Besides, the temperature variations may not be as extreme as in the Arctic Tundra.
Since the Alpine tundra is not limited to the polar region, you can find it in high mountain regions like the Alps, the Pyrenees, the European Scandes, the Asian Tibetan plateau, and the Caucasus Mountains, among others.
Despite the differences, both Tundra subtypes are habitats of similar mammals, birds, and insects.
Animals in the Tundra and Their Adaptations
Despite the harsh conditions in the Tundra biome, it serves as a habitat for dozens of land mammals, insects, and fish species. Millions of birds also migrate there each year for the marshes. The common tundra animals include the Arctic fox, musk oxen, caribous, and polar bears.
Small mammals include arctic ground squirrels and arctic hares.
These mammals are now adapted to the cold and have developed thick fur and massive fat layers to keep them warm. They have also mastered the art of burrowing and hibernation to depress their metabolism while avoiding the harsh winter precipitation.
The Tundra biome is also a hot spot for migration birds looking to feed, mate, and nest. Like mammals, most of these birds have thick whitish fur, which not only aids in camouflage but also helps keep them warm.
The birds include the Snowy Owl, Ross Gulls, Willow Ptarmigans, and the longest migrating bird in the world, the Arctic Tern.
Other less conspicuous than larger fauna species include fish and insects, which play a vital role in the ecosystem. The insects include arctic bumblebees, black flies, and mosquitoes, and thrive during the short but intense summer.
Besides aiding pollination, insects are a crucial food source for migrating birds and also hibernate during the winter when there’s no abundance. Other insect adaptations include deploying the antifreeze protein (AFP), which keeps their bodily fluids relatively warm. Like common fish like salmon, trout, flatfish, and cod, insects can survive and reproduce in the short tundra summer and rapidly complete their life cycles.
Plants of the Tundra
The Tundra region has about 1,700 plant species that endure the harsh climatic conditions and the permafrost. However, vegetation in this region is still limited due to the poor soil quality, dry conditions, extreme cold temperatures, and the snow-laden surface.
The permanently frozen ground leaves no space for deep-rooted plants; hence, this biome has no trees. The only surviving vegetation includes shrubs, lichens, labrador tea, crowberry, reindeer mosses, sedges, blueberry, grasses, liverworts, etc.
These plants in Tundra only get brief periods of growth during the summer, as the winters are characterized by darkness and extreme cold. However, vegetation in the Alpine tundra may do better since it experiences an almost constant sun exposure.
Nonetheless, vegetation in the Tundra biome has proved resilient, thanks to adaptation that includes reproduction through budding and division rather than sexually by flowering. The plants of the tundra conduct photosynthesis even with minimal temperatures or sunlight.
The vegetation is also notably short and very close to the ground, so the snow insulates it during the harsh winter.
Others, like the lousewort, willows, and cotton grass, have hairy stalks that help retain warm air near the stalk and aid flowering when temperatures reach freezing.
How Climate Change Impacts Tundra Biome Delicate Balance
The Tundra biome can be the coldest, harshest, and perhaps remote but not invulnerable. Developments on global warming and human disruptions have proven how sensitive a biome can be.
The most likely result from any of these scenarios is rapid thawing of the permafrost, which could have a ripple effect on the direct inhabitants and the entire global climate.
The permafrost covers about one and half times the carbon already in the atmosphere today, not to mention significant methane levels, another dreaded greenhouse gas. Besides, the alpine Tundra is an essential reservoir of fresh water and home to thousands of unique flora and fauna species.
Unfortunately, with the rising global temperatures, permafrost is thawing at an alarming rate and exposing greenhouse gas emissions, which will, in turn, catalyze the thawing process. The global surface-air temperature has risen by about 0.90C (1.50F) since 1900, but in the Arctic, the increase ranges at about 3.50C (5.30F) over the same period. The result has been a record-breaking winter warmth, and it is predicted that the region could be 7-80C warmer by the end of the 21st century.
Notable changes observed in the Tundra biome due to global warming include a gradual shrinking of the domain and the gradual advancement of the natural climatic tree line vertically upward. The high temperatures have also encouraged increased shrub growth, which changes the soil temperature and prevents the snow from reflecting out heat effectively.
The shrub growth has also been shown to crowd out lichen and other plants of the Tundra, which are crucial food sources for tundra biome animals like the caribou.
Moreover, the increasingly thawing permafrost has also contributed to the rising sea levels that have become a hurdle along the coastal areas. As the Tundra warms, we could see increased risks of wildfires such as the 2007 Alaska wildfire. Drought is also likely, as evidenced by a report showing a significant disappearance of lakes in Western Greenland from 1969.
The list of dire climate phenomena linked to the Tundra biome could go on and on, hence the need to promote and boost conservation efforts. Some of the ongoing Arctic Council‘s conservation initiatives to preserve the Tundra biome seek to address ship traffic and marine litter and engage indigenous people and local communities.
However, more work is needed globally to curb other activities, such as emissions that drive global warming, which leads to permafrost thaw. Practical tundra conservation efforts can mitigate climate change and preserve the earth’s ecological balance.