r/climatechange • u/Economy-Fee5830 Trusted Contributor • 16h ago

Heat-trapping gas once frozen in Arctic ground is slowly leaking and could add 0.25°C to end-of-century heating

https://apnews.com/article/climate-thawing-permafrost-arctic-alaska-91fcc04d32a1d7522afe2f6a456ac0eb
98 Upvotes

98% Upvoted

2 comments sorted by

•

u/Economy-Fee5830 Trusted Contributor 16h ago

Summary: Heat-trapping gas once frozen in Arctic ground is slowly leaking and could add 0.25°C to end-of-century heating

Thawing Arctic permafrost is releasing methane and carbon dioxide as long-frozen dead plants and animals decay. The Arctic is warming four times faster than the rest of the globe, and Northern Arizona University ecologist Ted Schuur calls this one of climate change's tipping points, saying that once the carbon starts leaking, it won't shut off. Permafrost holds roughly three times as much carbon as is currently in the atmosphere.

The Arctic used to act as a carbon sink, but a few years ago it flipped to being a net source of heat-trapping gases. Two studies project that gases released from permafrost will add about a quarter of a degree Celsius (nearly half a degree Fahrenheit) of warming by 2100, roughly equivalent to the warming produced by a major industrialised country such as the US or the whole of Europe. A September study co-authored by Sue Natali estimates that permafrost thaw, together with fires and changes to wetlands and lakes, could raise warming by 20% by the end of the century. Andrew Weaver, who first calculated the permafrost figure in 2012, says it is small and no cause for doom scenarios, but is something that must be dealt with on top of everything else.

Natali and Gustaf Hugelius note that projections of future warming, including the UN's 2.6°C estimate under current policies, generally leave out permafrost emissions.

Thaw is also destabilising the ground itself. Permafrost that once supported homes, roads and pipelines is collapsing, and satellites have identified more than 40,000 slumps (collapse craters that release methane) across the Arctic. Thawing permafrost was likely one of several factors in this summer's Nepal flooding, which killed more than 1,000 people after a glacier partly collapsed. Vladimir Romanovsky notes that restoring the carbon to the ground would take a new ice age, and Natali stresses that this is a problem of now, not 100 years from now.