The edge of a glacier with a mountain in the background

Glaciers such as Argentina’s Perito Moreno are projected to continue melting even if greenhouse-gas emissions fall. Credit: Mario Tama/Getty

Climate change

Glacier shrinkage is past the point of no return

But stringent action could forestall further melting in future centuries.

The dramatic shrinkage of the world’s glaciers is likely to continue in the coming century even if greenhouse-gas emissions are slashed in the next few decades.

Warming since the late nineteenth century has led to a marked retreat of most of the world’s glaciers. Ben Marzeion at the University of Bremen in Germany and his colleagues simulated the long-term response of thousands of glaciers to recent and projected climate change. The researchers found that glaciers are already committed to enough shrinkage to raise global sea levels by about 10 centimetres, even if global temperatures do not rise any further for centuries.

The Paris climate accord, adopted by 195 countries in 2015, aims to limit long-term warming to 1.5–2 °C above preindustrial levels. But such a temperature rise is likely to accelerate ice loss until at least the middle of the twenty-first century. Sustaining today’s glaciers would require a prompt return to pre-industrial climate conditions, the authors say.