Scientists covered 200 square metres of a Swiss glacier with sheep’s wool; early tests found it protected the ice about as well as plastic sheets, but only 0.02% of Swiss glacier ice is covered

A natural wool covering placed over 200 square metres of high-altitude Alpine ice has proved as effective at slowing summer melting as conventional synthetic tarpaulins, offering a possible biodegradable alternative to plastic sheets. Initial results from the “Keep It Wool” trial on the Tsanfleuron Glacier in western Switzerland show that prototype wool blankets protected snow and ice from heat about as well as plastic geotextiles.