In the context of the United Nations' International Year of Glacier Conservation, Swiss glaciers are melting at an unprecedented rate, and scientists warn that the Alps may never return to their former glory. Affected by the superposition of snow-less winter and extreme high temperatures in summer,Swiss glacier ice volume plunged again by nearly 3% in one year in 2025, making this year the fourth worst melting year after 2022, 2023 and 2003. Since 2015, Switzerland's glaciers have lost about a quarter of their overall volume, and more than 1,000 small glaciers have completely disappeared.
The research team responsible for Swiss glacier monitoring pointed out that there was significantly less snowfall in the winter of 2024/2025. In addition, October to March of the following year was the third warmest winter half on record, and the thickness of the snow layer in most areas was much lower than the average annual average. In parts of northern and central Graubünden, the amount of new snow even reached the lowest level on record. By the end of April, snow storage on the glacier was about 13% less than the 2010-2020 average.
After entering summer, June became the second hottest June on record. The high temperature further accelerated the melting of snow in high-altitude areas, and it was even difficult to find sustained snow coverage on the tops of many glaciers. Although the weather turned cooler and wetter in July, temporarily slowing down the melting rate, a heat wave occurred again in August. During this period, the zero isotherm once rose to more than 5,000 meters, resulting in significantly higher temperatures throughout the summer. Between July and September, a few cold air processes have brought new snow above 2500 meters, but long-term snow cover remains almost exclusively on the highest summit areas.
Against this background, the ice thickness of many typical glaciers has dropped to alarming levels. The Claridenfirn glacier in canton Glarus, the Plaine Morte glacier in canton Bern and the Silvretta glacier in canton Graubünden have thinned by more than 2 meters in one year. The Allalin and Findel glaciers in southern Valais suffered slightly smaller losses, but also lost about 1 meter in ice thickness. Affected by the rapid retreat of the ice tongue, the glacier lake in front of the Rhone Glacier is rapidly expanding, becoming one of the most intuitive evidences of glacier retreat.
Long-term observations also show that the past decade has been the fastest retreat of Swiss glaciers on record. Historical comparison images show that the Gries glacier in Valais has shrunk significantly from 1919 to 2025, and large areas of ice no longer exist. Researchers emphasize that if the global warming trend continues, many small and medium-sized glaciers will completely disappear in the next few decades, and the height of the traditional snow line and landform pattern of the Alps will also undergo profound changes.
The dramatic melting of glaciers not only results in a loss of visual landscapes, but also poses risks to mountain stability. GLAMOS project leader Matthias Huss pointed out that continued thinning and retreating glaciers weaken mountain structures and increase the likelihood of extreme events such as collapses, landslides and ice-rock avalanches. He gave the example of an incident in the Rocky Valley where rocks, ice and snow avalanched and buried the village of Blatten, which was one of the serious consequences of mountain instability.
This series of observations and analyzes was completed in cooperation with a number of Swiss institutions, including the Swiss Federal Institute of Technology in Zurich, the Federal Environment Agency, MeteoSwiss (Swiss Meteorological Office), the Federal Cartographic Office and the Swiss Academy of Sciences. The relevant monitoring work is also integrated into the Global Climate Observing System (GCOS) framework. The research team calls on Switzerland and the world to further increase emissions reduction and adaptation actions, otherwise in the next few decades, the familiar "ice and snow kingdom" of the Alps will only exist in historical photos.