Sheep wool tested as eco-friendly alternative to plastic for glacier protection

An experiment conducted by the Summit Foundation, with participation from the University of Lausanne, has demonstrated that sheep wool blankets can reduce glacier melting as effectively as synthetic plastic geotextiles. The “Keep it Wool” study, performed in Les Diablerets, Switzerland, showed that wool covers reduced melting by 50-70 percent.

Unlike synthetic materials, sheep wool is a natural, renewable, and biodegradable resource that does not risk releasing microfibers into the water cycle. However, experts note that such measures cannot halt overall glacier loss. The cost and labor required to cover glaciers are prohibitive, and current textile coverage accounts for only about 0.02 percent of Switzerland’s total glacier area.

While these covers can preserve approximately 300,000 cubic meters of snow annually, this is a small fraction of the nearly one billion cubic meters lost each year. Swiss glaciers have lost nearly 40 percent of their volume between 2000 and 2024.