Swiss glaciers lose over 5% of ice, threaten water supplies

Swiss glaciers have lost more than 5 % of their remaining ice in the past twelve months, a near‑record melt that scientists say is “extraordinary” and driven by this summer’s intense heatwaves across the Alps. The loss, reported by Glacier Monitoring Switzerland, marks the fastest yearly decline ever recorded for the country’s high‑altitude ice.

The rapid melt follows a winter with unusually low snowfall and a spring that saw early, severe heatwaves in May and June. With less fresh snow to reflect sunlight, the darker bare ice absorbed more solar energy, accelerating the melt. Glaciologists had previously labelled a 2 % loss in a year as “extreme”; this summer’s 5.5 % drop far exceeds that benchmark. The trend mirrors broader climate change patterns, as rising global temperatures from fossil‑fuel emissions push Alpine glaciers toward a tipping point.

Scientists estimate the glaciers released about 2.2 trillion litres of meltwater between July and September. That flow temporarily eased water shortages for irrigation, hydropower and even river traffic, but it also drained a centuries‑old reservoir of frozen water. “Every drop of water that runs off during these heatwaves is old water that’s been stocked in the glacier ice for decades,” said Dr Matthias Huss, director of Glacier Monitoring Switzerland. He warned that smaller glaciers will soon be unable to replenish rivers at the same rate, threatening the Rhine and other waterways that already hit record lows this summer. The thinning ice also destabilises mountain slopes, raising the risk of landslides and flash floods, as seen in Nepal’s August disaster.

The melt signals a looming water crisis for Switzerland’s farms, power stations and transport routes. With glaciers shrinking faster than anticipated, the country faces a future where natural water reserves can no longer buffer extreme heat. Experts say the only way to curb the trend is to cut greenhouse‑gas emissions sharply and invest in alternative water storage. Until then, each summer heatwave will draw down an increasingly fragile ice bank, leaving less water for the next generation.