In 1971, researchers made a surprising discovery while studying Greenland’s ice: temperatures on the island increased dramatically over short periods thousands of years ago. The results showed that abrupt warming could occur over just several decades. and changed the way they think about natural climate change.

Today, the world is grappling with another major change, this time due to anthropogenic activities. And scientists are making predictions about how the ice will soon evolve as temperatures hot.

In a new study published today in the journal The cryosphereresearchers modeled the extent of glacier melt by 2100. The results show that more ice will disappear than predicted in the latest report from the Intergovernmental Panel on Climate Change (IPCC), generally considered the scientific consensus on the state of climate change.

“We have a field program on a glacier in Switzerland, where we go back and see how much has melted, and the changes are absolutely enormous,” says lead author and glaciologist Harry Zekollari of ETH Zurich and the Vrije Universiteit Brussel .

The vast majority of the planet’s 200,000 glaciers also show clear signs of warming, thinning on average between three and six feet per year.