Vanishing Permafrost

Vanishing Permafrost

Subject: Geography

Context: About 13% of permafrost, an area on Daisetsu Mountains in Japan, estimated to be approximately 150 sq. kms. in 2010 is likely to disappear by 2100 under business as usual scenario.

Concept:

About the permafrost:

• Areas with ground temperatures that remain below zero degrees celsius for more than two years are called permafrost.
• It is composed of rock, sediments, sand, dead plant and animal matter, soil, and varying degrees of ice and is believed to have formed during glacial periods dating several millennia.
• It is mainly found near the polar zones and regions with high mountains covering parts of Greenland, Alaska, Russia, Northern Canada, Siberia and Scandinavia. These are found in mountains as well as high latitude tundra and taiga regions.
• Its thickness reduces progressively towards the south and is affected by a number of other factors, including the Earth’s interior heat, snow and vegetation cover, presence of water bodies, and topography.

Permafrost & Global Warming:

• A study has shown that every 1 degree Celsius rise in temperature can degrade up to 39 lakh square kilometers due to Permafrost thawing (the ice inside the permafrost melts, leaving behind water and soil).
• Permafrost in the Arctic region stores large amounts of methane, which is a greenhouse gas that contributes to climate change. 
• When permafrost is frozen, the organic carbon contained in it can’t decompose, or rot away and as permafrost thaws the microbes in the soil decompose the dead organic matter (plants and animals) to produce methane (CH4) and Carbon Dioxide (CO2) which in turn will increase the rate of global warming. This will result in a vicious cycle that may result in a climate catastrophe.