Evidence from Siberian caves has suggested that a global temperature of 1.5C could see the huge areas of permafrost across Siberia, thaw with devastating effects. Within the permafrost it is thought there are over a trillion tonnes of CO2
and Methane which could be released into the atmosphere from the thaw.
The permafrost, where the ground becomes entirely frozen, permanently in layers which can be tens to hundreds of metres thick has been studied by a team of scientists, who have looking at speleotherms (Stalactites and Stalagmites) in caves along the frontiers of the permafrost. These speleotherms measure changes in temperatures as they only grow when there is liquid water within the caves and have recorded 500,000 years of changing permafrost and temperatures. Records show that changes in temperatures of 1.5C previously have seen significant permafrost melting.
Dr Anton Vaks from Oxford University states:
"As permafrost covers 24% of the land surface of the Northern Hemisphere,
significant thawing could affect vast areas and release (billions of tonnes) of
carbon. This has huge implications for ecosystems in the region, and for
aspects of the human environment. For instance, natural gas facilities in the region, as well as power lines,
roads, railways and buildings are all built on permafrost and are vulnerable to
thawing. Such a thaw could damage this infrastructure with obvious economic
implications." Showing that this has significant local problems as well as global problems with greenhouse gases.
It is a significant problem globally with increasing temperatures comes increasing melting of permafrost and ice caps. The permafrost holds trillions of tonnes of greenhouse gases which would further ice melt and temperature increase and the melting of ice caps reduces the albedo (the reflectivity of an object) which means that energy from the sun will have less area to be reflected back into space and be absorbed increasing global warming. This is a positive feedback system.
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