Swiss glaciers lost 5.5 percent of their ice in eight months, 19.4 percent since 2021

Swiss glaciers lost 5.5 percent of their ice volume in the first eight months of 2026, the Swiss Glacier Monitoring Network and the Swiss Commission for Cryosphere Observation said on Thursday, 1 October. That single season takes the loss since 2021 to 19.4 percent, just under a fifth in five years. The 2026 figure sits just short of the record melt of 2022.

The mechanism the two bodies described is a sequence, not a single heatwave. Winter left little snow. Summer then ran hot. Snow is the cover that keeps ice from the sun. A thin winter means the ice is exposed earlier, and a hot summer spends that exposure. The network's annual report is the document that turns that sequence into a percentage. Mean thickness on individual glaciers fell by between 2.5 and 4 metres. Some glacier tongues, the narrow ends that reach toward water, retreated by up to 10 metres. Between July and September the glaciers lost about 2.2 trillion litres of water, which the researchers set at four times the drinking water Swiss households use in a year.

The New York Times, reporting the same release, put the 2026 loss at more than 5 percent and the five-year loss at almost a fifth. The Guardian's 5.5 and 19.4 are the tighter figures, and they are the ones to cite. Both accounts agree on the winter-then-summer pattern and on the comparison with 2022. Many small glaciers have already gone. Matthias Huss, visiting what was the Plattalvafirn, or Griess glacier, in September, described a flank that had lost 99 percent of its area in 20 years and was now rock with scattered blocks of old ice melting on the stone. The joint statement from the two bodies said Alpine glaciers have no long-term chance of survival under these conditions.

A 5.5 percent loss in eight months is easier to misread than a 19.4 percent loss in five years. The first is a season. The second is a trend that has now eaten almost a fifth of the ice Switzerland had in 2021. The years in between were not all record years. They were negative years stacked on each other, which is why a season that is only the second-worst on record still produces a five-year number that looks like a collapse. The record year, 2022, did not reset anything. It was followed by more loss.

The water number is the one with a domestic use. 2.2 trillion litres from July to September is melt, not a reservoir that can be called on next July in the same form. Some of it runs through the Rhone and the other Alpine rivers in the weeks it melts. Some of it is the ice that will not be there to melt in a dry August ten years from now. Swiss hydropower and valley water use have treated glacier melt as a summer supplement. A fifth gone in five years is a supplement being spent down.

Dust and sun made the season slightly less extreme than it might have been, the scientists said. Limited Saharan dust meant less darkening of the remaining snow, and snow cover at the end of winter, while poor, was a little greater than in the worst years, with more sun later. Those are reasons the 2026 loss stopped short of 2022. They are not reasons to treat 5.5 percent as a pause. The network's own comparison is the five-year total.

The next annual report will add whatever the winter of 2026-27 leaves on the ice. If that winter is thin again, the 19.4 percent becomes the base for another early exposure. The Thursday figures already close one argument. This is not a single bad summer. It is five years, a fifth of the ice, and a season that nearly matched the worst year on the books.