We have heard since decades that the Arctic is melting. The Arctic or the Arctic Circle as we call it covers roughly 4% of the earth’s surface that runs through the Arctic Ocean, the Scandinavian Peninsula, North Asia, Northern America and Greenland. Majority of the Arctic region is composed by the Arctic Ocean. The vegetation is a type of a biome, called Tundra. The Arctic Tundra constitutes dwarf shrubs, sedges, lichens, grasses and mosses majorly defined by permafrost.
Permafrost is a thick layer of soil that remains frozen permanently almost all the time and hence the name. It comprises 24% of the land in the Northern hemisphere. Permafrost areas have a very cold temperature and a very fragile topsoil layer. This topsoil layer is said to be the most active layer. Beneath the active layer, the permafrost is either formed when the ground freezes more than two consecutive years or even maybe thousands of years. It is made up of rocks, sediments, soil and a varying amount of ice that binds all these elements together. It also varies in its thickness ranging from some few feet to 5000 feet in thickness. It stores the carbon remains of plants and animals that froze without decomposing. Unfortunately, due to rising global warming, the permafrost warms and thaws releasing carbon dioxide and methane. Rather than storing carbon, this situation can inevitably become a source of planet-heating emission.
The active layer of the topsoil which comprises of dwarf shrubs will be about 13 feet deep. During summer when this layer thaws the roots of the plants and the microbes in the soil respires CO2. Some microbes break down the organic matter that constitutes the CO2 emission. In the absence of oxygen when the soil is saturated with water microbes like archaea produce methane. Methane is 20 to 30 times highly potent in aggravating at global warming than carbon dioxide.
On a positive note, the one thing that protects the permafrost from impacting climate change is peat. Peat is a partially decomposed plant material in under anaerobic saturated water. This layer above the permafrost acts as a buffer against severe degradation. However, sometimes mishaps like wildfires brought about by lightning storms burn the peat soil releasing a huge amount of CO2. Not only that, the burnt ground absorbs a lot of solar radiation which consecutively contributes to global warming directly.
The impact of Permafrost thawing is so dreadful. When the ice in permafrost melts, the ground under becomes unstable and can collapse causing landslide, coastal erosion and floods. It can also bring harm to our ecosystem. The depression during the thawing of permafrost gives birth to Thermokarst Lake releasing methane. The drainage from the bubbling basin drains the wetlands and lakes destroying the important biological resources. The sediments from the landslide affect the life of plants and the food chain of the ecosystem. Due to change in the landscape, the pattern of migration and bedding of birds is stirred.
Scientists believe that the bacteria and virus that been frozen and surviving under permafrost for thousand years can revive back. How much the planet warms due to thawing depends upon how much carbon imprints we leave behind. It is the responsibility of every one of us to save our planet by contributing with a little effort of following the 3 R’s REDUCE, RECYCLE and REUSE.
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