Cryosphere damage likely even with temperature reduction, new report finds

The planet has already warmed by 1.3 degrees Celsius since pre-industrial times, and current projections indicate a peak temperature of around 3 degrees Celsius under existing policies. This level of warming would trigger widespread permafrost thaw, potentially disrupt ocean circulation, and accelerate ocean acidification. Scientists emphasize the need to remove significant amounts of carbon from the atmosphere to bring long-term warming below 1 degree Celsius by 2150.

The report details permanent consequences such as glacier melt contributing to sea level rise and threatening water security, even if temperatures are brought back down to 1.5 degrees Celsius. James Kirkham, a glaciologist at ICCI and lead author of the report, stressed that the cryosphere is a crucial component of the climate system. He cited a recent ice rock avalanche on the Nepal-China border that killed thousands and caused damage equivalent to 10% of Nepal’s GDP, alongside the loss of 20% of Switzerland’s glacier ice in the last five years.

The findings are particularly relevant as world leaders gather in Turkey for the 31st annual Cop climate conference. The report underscores the rapid and accelerating melting of glaciers, ice sheets, and polar oceans, with consequences ranging from sea level rise threatening hundreds of millions of people to the release of greenhouse gases from thawing permafrost. Glaciers are projected to retain only about 70% of their current volume even with a return to 0.8 degrees Celsius of warming.

The report also notes that ice sheets in Greenland and Antarctica are melting six times faster than in the 1990s and will continue to lose ice even with a brief overshoot and a return to 1.5 degrees Celsius. Scientists suggest a safer long-term temperature limit for polar ice sheets is closer to 1.0 degrees Celsius, or even lower. A recent UNEP report called for emissions cuts of 18% by 2030 and 45% by 2035 to avoid exceeding 1.7 degrees Celsius of warming, concluding that there are “no good outcomes” above 1.5 degrees Celsius.

Climate scientist Bill Hare, CEO of Climate Analytics, stated that the report demonstrates the irreversible nature of climate impacts and the responsibility of those who have hindered climate action.