The Aletsch glazier, situated in the Swiss Alps, is the largest glazier in Europe, 15 miles long and up to 900 meters deep. People used to be afraid of it growing and moving down, burying forests, paths and houses in its path. Well, not anymore. Due to climate change it is melting rapidly; some say it will be almost gone by 2100.

Deep within, chunks of ice sometimes shift, causing a noisy roar. Locals, however, know this is the noise of lost souls trapped within the ice. At midnight they come out and when they touch you it means you are going to die.

Detailed and long-term monitoring programs showed that 2022 and 2023 offered a “perfect storm” for Swiss glaciers, starting very early in the season. Both years began with a winter that was particularly dry—which meant that there was very little protective snow cover on the glaciers. In addition, southwesterly winds repeatedly brought significant amounts of Saharan dust into the Alps, which settled on the thin snow cover. The resulting dirty, red-yellow snow absorbed more solar energy and melted much faster (Réveillet et al., 2022). Finally, summer heat waves containing record temperatures rushed in. The combination of these three factors—little snow cover, overlain with energy-absorbing dust, followed by record-high temperatures—led to unprecedented ice losses that were hardly imaginable up to that point.

– Bulletin of the Atomic Scientists