DOHA – Policymakers and climate scientists must monitor and prepare for large carbon dioxide and methane emissions from permafrost, says the startling report on additional global warming as a result of thawing permafrost, released by the United Nations Environment Programme (UNEP) during the Conference of Parties (COP18) on climate change, in Doha last year.
Permafrost is soil that has remained below 0C (32F) for more than two years and occurs in regions where the summer warmth fails to penetrate the ground sufficiently to thaw the soil. These conditions prevail in high-latitude or high-mountain areas that cover roughly a quarter of the Earth’s land surface – including Alaska, Canada and Siberia.
The report reveals that permafrost covering almost a quarter of the northern hemisphere contains 1 700 gigatonnes of carbon, twice that which is currently in the atmosphere. Warming permafrost can cause serious local problems, such as infrastructural damage, as a result of unstable ground, as well as ecological damage.
To make matters worse, the potential hazards of carbon dioxide and methane emissions from permafrost have thus far not been included in climate prediction modeling. Lead author Kevin Schaefer from the University of Colorado’s National Snow and Ice Data Centre, said the warming permafrost could emit the equivalent of 43 to 135 gigatonnes of carbon dioxide, by 2100 and 246 to 415 gigatonnes by 2200.
These emissions are expected to start within the next few decades and continue for several centuries. Dominant ecosystems in permafrost regions are boreal forests to the south and the tundra to the north. Since permafrost is impermeable water, rain and melted water pools on the surface, forming numerous lakes and wetlands, which are used by migratory birds as summer breeding grounds.
Ecosystem disturbances due to degrading permafrost will change species composition and with it animal habitat and migration, the report stated. The degradation and the resultant drying of the land can also result in disturbances such as fires. Thawing permafrost is structurally weak resulting in foundational settling that can damage or destroy buildings, roads, pipelines, railways and power lines.
The report recommends a special assessment report on how carbon dioxide and methane emissions from permafrost would influence global warming, to adequately monitor permafrost and those countries directly affected to evaluate potential risk, damage and cost. Countries with the most permafrost are Russia, Canada, China and the United States.