How sheep could help Switzerland's melting glaciers

In the winter, you're likely to reach for a woolly jumper to keep you warm when you're cold.

But a new project in Switzerland is using wool for the opposite reason - to keep glaciers cool in the summer.

Currently big plastic sheets are being used but they can shed synthetic fibres and microplastics into the surroundings.

It's done to help slow down how quickly the ice melts in the warmer weather, something that scientists say is getting worse due to climate change.

According to Glacial Monitoring in Switzerland (Glamos), the country has lost a quarter of its ice mass in the last 10 years.

Researchers are looking for ways to help slow this down and have been using plastic tarpaulins in some areas on the Alps for years.

While the large sheets are partly used to help protect small sections of glaciers, it's largely done for tourism.

That's because the Alps are a popular destination for people looking to go skiing or snowboarding.

Snow that is protected from melting in the summer can be harvested and used at the start of winter to provide enough snow for people to use for those winter sports.

The plastic tarpaulins are currently used to reflect sunlight and reduce heat absorption but they can shed synthetic fibres and microplastics into the snow and ice.

Researchers wanted to see if there was a natural and biodegradable option like wool that could work just as well as the current method, which helps to reduce glacier melt by 50% to 70%.

Timothee Steiner from the Summit Foundation who led the project alongside the University of Lausanne said:

"[Wool's] a local material that's undervalued.

"In Switzerland, between 40 and 70 percent of sheep's wool is wasted, there are many estimates. But there's a real waste of wool.

"So our idea is to use this underutilized, wasted material to create a tool for protecting glaciers."

"We came all summer to measure the melting and the ice depth...We used two prototypes, one thinner and one thicker—and the thicker prototype is even slightly more effective."

"In Switzerland, only 0.02% of glaciers are covered, which is practically nothing," Timothee continued.

"Therefore, thinking we can save glaciers by covering them with tarpaulins is like putting a band-aid on a gaping wound that keeps getting bigger.

"The main focus should be on combating climate change to save our glaciers from the melting they are currently experiencing."

According to research published in the Science journal in 2025, half of the ice left across the world's mountain glaciers could be saved if global warming is limited to 1.5C.