This moment when a glacier lost all the snow and ice accumulated during the winter is called the decline in glaciers – in English “Glacier Loss Day“(GLD) -, told Keystone -ATS the glaciologist Matthias Huss, researcher at the EPF of Zurich and at the University of Friborg. So far, this day has been recorded only once early in the year, as the data of the Swiss Glamos measurement network show: in 2022, record year, it fell on June 26.”We are quite clearly in second position in 2025, so before other very bad years like 2023 or 2017“, note Matthias Huss.
In principle, the more this day comes early, the more the phase during which the glacier is exposed without protection to summer heat is longer. Normally, the GLD falls 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 Loss Day glacier 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.
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.
