The snow and ice accumulated in the Swiss Alps during the winter have already melted and the glaciers are now losing mass, experts in charge of their surveillance said on Friday. This “day of the loss of glaciers” had only been early in 2022.
Any new cast iron this year will lead to a decrease in the size of Swiss glaciers, said the surveillance service for glamos glaciers. The critical threshold is generally reached later in the season and its early arrival is a new blow for the country’s 1400 glaciers, who continue to retreat at an alarming rate.
Until now, the “day of the loss of glaciers” (or “Loss Day glacier”, GLD) had been recorded only once early in the year: in 2022, record year, it had intervened on June 26. “We are quite clearly in second position in 2025, so before other very bad years like 2023 or 2017,” said Glaciologist Matthias Huss, researcher at the EPF in Zurich and at the University of Friborg.
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Normally in August or September
In principle, the more this rocking day arrives early, the more the phase during which the glacier is exposed without protection to summer heat is longer. Normally, he fell in August, and even in September in rare cases. Last year, for example, it was recorded on August 11.
But “for a healthy glacier, or even growing, there is no GLD at all, that is to say that we never arrive at the situation where the reserves accumulated during the winter are completely exhausted”, underlines the researcher.
Currently, the GLD 2025 is a first estimate which could still change by the end of the year, says Matthias Huss. The mass that Swiss glaciers will actually lose by the end of the cast iron period will depend on the weather conditions for the next three months.
According to him, the glaciers could lose as much mass as during the 2022 record year, but they could also undergo only moderate loss if the weather conditions are similar to those of 2021, that is to say rainy and not very hot.
The glaciers have been founded for 170 years
The Glaciers of the Swiss Alps began to withdraw approximately 170 years ago. At first, this withdrawal was still shy. The years of losses alternated with periods of a few decades when snowfall and cast iron was balanced. Since then, the cast iron has accelerated strongly.
Since 2000, the volume of Swiss glaciers has melted by 38%. In 2000, the volume of ice of all Swiss glaciers was 74.9 cubic kilometers; In 2024, it was only 46.5 cubic kilometers.
Almost a quarter of Swiss glaciers can still be saved, as the Swiss Academy of Natural Sciences had indicated in a information sheet published in the spring. But only with strong climatic measures, which would require a clear reduction to zero of global greenhouse gas emissions.
As the glaciers react with delay to climate change, even if the temperatures remained stable now, it would be necessary to expect a decline of a third of the volume of ice in the space of 25 years.
>> Return the program taken from the earthen dedicated to glaciers:
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