There are 60 glaciers in Switzerland that could threaten inhabited areas, roads and railways. Despite one of the oldest and most developed monitoring networks in the world, it is often impossible to anticipate a deadly glacier collapse such as the one on the Marmolada in the Dolomites. When Christophe Lambiel discovered that water was circulating at the base of the Moiry hanging glacier in Canton Valais, he was not only surprised but also worried. The geomorphology expert and professor at the University of Lausanne has been measuring the glacier's temperature for about a year, using detectors inserted into two boreholes. Inside the glacier and at its base, temperatures are negative. However, on 5 June, temperatures rose to 0°C in just a few hours. "When this happens, there is a risk of a break-up,' he says. The cause of the temperature rise was the intrusion of meltwater, which reached the point where the glacier is 'glued' to the rock. If water gets in between, the glacier...
