Permafrost is ground that remains frozen for two or more years. Globally, these frozen soils hold an estimated 1,500 billion tons of carbon. This carbon reservoir is stable as long as it remains frozen. Higher temperatures cause the permafrost to thaw. This process can release carbon dioxide and methane, which causes further warming. Exactly how much of these gases could be released is one of the large unknowns in the Earth’s climate system. The thawing trend appears to be irreversible. Even with a global reduction of greenhouse gases, the current area of permafrost would still shrink by 45 per cent by 2100. This has consequences for coastal erosion, infrastructure, ecosystems and humans.
From collection: Global linkages – a graphic look at the changing Arctic (rev.1)
Riccardo Pravettoni and Philippe Rekacewicz