Thawing permafrost and soil collapse in Russia. Photo: Gustaf Hugelius
Thawing permafrost and soil collapse in Russia. Photo: Gustaf Hugelius


“New research confirms that permafrost emissions alone will reduce our remaining emission window for +1.5 degrees by a third. At the same time, we see that higher warming exposes the Earth system, and humanity, to irreversibly changes for centuries to come,” says Gustaf Hugelius of the Bolin Centre at Stockholm University, one of the lead scientists behind the report.  

The cryosphere – Earth’s frozen regions– includes permafrost, sea ice, glaciers, snow and ice sheets. This call for action on emissions reduction comes in connection with the release of the “Cryosphere1.5° Report” at COP-25 in Madrid. The report combines the results of the IPCC Special Reports on 1.5° (2018), and on the Ocean and Cryosphere (2019) – plus importantly, research conducted since. Authored and reviewed by over 40 IPCC and other leading cryosphere researchers, it urges governments to aim for 1.5°C global temperature rise over pre-industrial levels.

Abrubt thaw events increases emissions

Among its most important messages are an increase in anticipated permafrost carbon emissions due to “abrupt thaw” events, which greatly reduces the window of how much emissions humans can produce.

Gustaf Hugelius at COP-25 in Madrid. Photo: Stockholm University
Gustaf Hugelius at COP-25 in Madrid. Photo: Stockholm University

“More permafrost emissions from abrupt thaw will come as methane, which feeds warming more intensely in the near-term”, says Gustaf Hugelius. These additional emissions will in turn force even more Arctic sea ice loss and melt of ice sheets in Greenland and Antarctica that raises sea levels globally.  

The Report’s Executive Summary states the long-term effects of destabilizing the cryosphere. There is a far greater risk of massive irreversible sea-level rise at 2°C, on a scale of 12–20 meters or more in the very long term. It also highlights the combined stress placed on polar ocean fisheries by acidification – which is occurring faster in cold polar waters than anywhere else. The Report also describes a future with almost no glaciers outside the Himalayas and polar regions by 2°C, compounded by snow loss harming water supplies.

The “Cryosphere1.5° Report” chose not only to combine the snow and ice findings of the two IPCC reports, but also include newer research since, because cryosphere science is moving quickly. Yet, these will not be reflected by the IPCC until its next full Assessment Report in 2021, well after countries set their new Nationally Determined Contributions (NDCs) in the course of the coming year leading to COP-26 in Glasgow.
“There is a great need, at this end stage of the Madrid climate talks and as countries head home, for decision makers to be aware of the level of risk we’re facing if we wait until it’s too late to prevent or at least slow these cryosphere dynamics. We all need to treat 1.5°C as the real guardrail,” says Pam Pearson, Director of the International Cryosphere Climate Initiative which coordinated the report.

More information

Download the “Cryosphere1.5° Report”.