Year by year
Every autumn, observers walk to the snouts of Swiss glaciers and measure how far they have moved. This is that record, since 1880, with the events that shaped it.
Advancing and retreating
Share of measured glacier tongues that advanced (blue) or retreated (red) each year; years with fewer than five measurements left out. Advances clustered in the 1910s–1920s and again from the mid-1960s to the mid-1980s, after cooler, snowier years. Since the late 1980s almost every glacier has retreated every year. Click a year to open it.
The record years
Annual change of total Swiss glacier volume. 2022 and 2023 together removed 10% of the ice; 2026 added another 5.5%. Sources: SCNAT factsheet 2025, GLAMOS 2025 and 2026.
Milestones and events
The Giétro flood
Ice from the Giétro Glacier dammed the valley. When the dam gave way, 20 million m³ of water reached Martigny in 90 minutes.
End of the Little Ice Age
Alpine glaciers reach their last major maximum. The 1850 inventory maps them at 1,788 km² in Switzerland.
Measurements begin
F.-A. Forel starts annual length measurements on about 30 Swiss glaciers. The network later grows to about 160.
The Altels ice avalanche
A cold hanging glacier broke off the Altels in one piece: about 4 million m³ of ice, the largest ice fall ever observed in the Alps.
Mass balance
Stake measurements begin on the Silvretta, Clariden and Aletsch glaciers, among the longest such series in the world.
The 1931 inventory
Mapped from terrestrial photographs: 1,494 km² of ice.
Mattmark
The tongue of the Allalin Glacier broke off above the Mattmark dam construction site and killed 88 workers.
The 1973 inventory
The first complete modern inventory: 1,311 km².
The 2003 heatwave
Swiss glaciers lost 3.5% of their volume in one summer. It stood as the record until 2022.
The Schnidejoch finds
A melting ice patch on a 2,756 m pass gave up objects spanning 6,000 years, including a Neolithic bow.
A bridge over a new lake
The retreat of the Trift Glacier left a lake where hikers used to walk on ice. A suspension bridge replaced the crossing.
The Grindelwald glacier lake
A lake on the collapsing tongue of the Lower Grindelwald Glacier drained suddenly in 2008. A tunnel through the rock now keeps it low.
The 2016 inventory
1,400 glaciers, 961 km².
Moosfluh starts to slide
When the Aletsch Glacier thinned below a critical level, the valley flank it had been holding up accelerated to 80 cm a day.
The Dumoulins come home
A couple who vanished in 1942 was found in the retreating Tsanfleuron Glacier, 75 years later.
Piz Cengalo and Bondo
Three million m³ of rock fell on a small glacier, took its ice with it and turned into a debris flow that reached the village of Bondo.
A predicted collapse
Radar showed the Trift Glacier on the Weissmies speeding up to 2 m a day. The village was evacuated, and the ice fell the next morning.
Lac des Faverges empties
A lake on the Plaine Morte Glacier drained through the ice in 24 hours and flooded the village of Lenk.
A funeral for the Pizol
About 250 people climbed to 2,700 m to mourn a glacier that had lost most of its ice since 2006.
A border on the move
The Swiss–Italian border follows the watershed. As the Theodul Glacier melted, the watershed moved under a mountain hut.
The record year
A snow-poor winter and a hot summer: Swiss glaciers lost 5.9% of their ice in one year.
The glacier vote
A popular initiative named after the glaciers led to a law that sets net zero emissions by 2050. Voters approved it with 59%.
Piz Scerscen
About a million m³ of rock and ice fell from Piz Scerscen and ran some 5 km down the Tschierva Glacier.
Blatten
Rockfalls overloaded the Birch Glacier until it collapsed. Rock and ice buried most of the village of Blatten, which had been evacuated nine days before.
A quarter in ten years
Another 3% gone in 2025. Since 2015 Switzerland has lost a quarter of its glacier ice.
The second-worst year
The hottest summer on record: Swiss glaciers lost 5.5% of their ice in one year, second only to 2022.