Switzerland is trying something unusual to protect its rapidly shrinking Alpine glaciers — covering parts of them with sheep’s wool.The idea may sound strange, but researchers say the natural fibre could offer a more environmentally friendly alternative to the synthetic sheets that have been used for years to slow the summer melting of snow and ice.The experiment, known as “Keep It Wool,” is being carried out on the Tsanfleuron Glacier at Glacier 3000 in Les Diablerets, western Switzerland. It brings together the Summit Foundation, the University of Lausanne and Swiss glacier researchers.Why are Swiss glaciers being covered?Protective sheets are already used in parts of the Alps to reduce glacier and snow melt during the warmer months.The principle is relatively simple: the coverings shield snow and ice from sunlight and reduce heat exchange, allowing the material underneath to melt more slowly.Synthetic geotextiles can significantly reduce melting in the areas where they are installed.But they come with an environmental drawback — they are generally made from plastic-based fibres, which can deteriorate over time and release tiny synthetic particles into the surrounding environment and meltwater.That has prompted researchers to ask whether the same job can be done with a material that is natural and biodegradable.Their answer, for now, is wool.The unusual glacier experimentIn June 2026, researchers placed two woollen covers, each measuring 100 square metres, over sections of the Tsanfleuron Glacier.A synthetic geotextile of comparable size was installed nearby, providing a benchmark against which the wool could be tested.The wool blankets were produced by Swiss company Fisolan, while the scientific work involved researchers associated with the University of Lausanne and the Swiss Glacier Monitoring Network, Glamos.Measurements were collected every two weeks throughout the summer. Researchers were looking at two key questions: could wool withstand the harsh conditions of a high-altitude glacier, and could it protect the underlying snow and ice as effectively as conventional material?The first results have been encouraging.Wool performed surprisingly wellAccording to the Summit Foundation, the two wool covers provided protection comparable to the synthetic geotextile during the first summer of testing. The organisation says the collected data still needs to undergo further analysis.That result is significant because durability was one of the obvious concerns surrounding the experiment.A glacier cover has to withstand strong winds, precipitation, freezing conditions and prolonged exposure to the elements. If a natural fibre breaks down too quickly, its usefulness as a protective material would be limited.The initial trial suggests that wool may be capable of handling those conditions better than expected.Why sheep’s wool?There is another reason Switzerland is interested in wool: much of the country's sheep wool currently has little commercial value.An official Swiss research project describes wool as a local resource that is often discarded, with estimates suggesting that as much as 80% of Swiss sheep wool goes unused. The “Glacier Wool” research initiative is exploring how the material could be turned into biodegradable glacier coverings.That creates an unusual climate solution with two sides to it.Instead of relying on a petroleum-based synthetic material, researchers could potentially make use of a renewable agricultural resource that is already available locally.Wool is also naturally biodegradable, meaning it does not present the same microplastic concern associated with synthetic fibres.But can wool really save a glacier?Not on its own.The wool experiment is designed to find a better way to protect small, strategically important areas of snow and ice, rather than stop glacier loss across Switzerland.Protective textiles currently cover only about 0.02% of Switzerland's glacier surface. The Summit Foundation estimates that these measures preserve around 300,000 cubic metres of snow annually, while Switzerland loses close to one billion cubic metres of ice each year. That puts the experiment into perspective.Even if wool proves cheaper, durable and environmentally preferable to synthetic covers, it cannot reverse the wider effects of rising temperatures.A small experiment with a bigger climate messageSwitzerland's glaciers have been retreating rapidly, making the search for ways to slow local ice loss increasingly urgent.The attraction of the wool project is not that it offers a miracle cure. Instead, it demonstrates how climate adaptation can sometimes involve looking at familiar materials differently.A fibre that once had little value could potentially become part of an effort to protect another threatened natural resource.For now, the researchers are continuing to analyse the results from the 2026 trial. If the performance of wool holds up over longer periods, the experiment could open the door to wider testing in Alpine regions.But the fundamental message remains unchanged: no glacier blanket, whether made from wool or plastic, can substitute for cutting greenhouse gas emissions.
