Europe's Roof Melts: Record June Heat and a Serious Threat to Alpine Glaciers

The extreme heatwave sweeping across Europe is not only setting unusual records in southern cities, but is also leaving a profound mark on the high mountains. In the Alps, the freezing point has risen above 5,100 meters, an altitude unthinkable for June until recently.

This week, Switzerland has registered its highest freezing level since records began: 5,184 meters, according to data from meteorological balloons launched from Payerne. This figure exceeds the previous record set in 1995 by nearly 70 meters and surpasses the summit of Mont Blanc, Europe's highest peak, by over 300 meters. In France, the same phenomenon has elevated the freezing line to 5,135 meters, an unprecedented milestone for the month of June.

In the words of Swiss glaciologist Matthias Huss, the situation is alarming. Measurements at the Griesgletscher glacier indicate accelerated melting, more than a month ahead of the average, surpassing even the extreme values of the 2003 summer. This acceleration is not anecdotal: according to recent studies, 39% of the ice in Central European glaciers has disappeared since 2000.

The consequences are already visible. Glaciers like Pisaillas in Val d’Isère have recorded temperatures of 13.6 °C at over 3,100 meters altitude, leading to the formation of lagoons and areas impassable for summer skiing. Resorts like Les 2 Alpes and Val d’Isère plan to close their slopes in the coming days, while Tignes hopes to remain operational until July 20, if conditions allow. But even that is in doubt.

The situation recalls the dramatic summer of 2022, when all European glaciers — except Hintertux in Austria — had to close their summer activities, weakened by a winter with scarce snowfall and an unforgiving summer.

A warmer future, less white

The trend is clear. Increasingly, glaciers show signs of structural exhaustion. It's not just about losing surface snow: the permanent ice that feeds rivers, regulates the local climate, and supports alpine ecosystems is disappearing at an alarming rate.

If this progression of warming and irregular winter precipitation continues, the next 10 to 15 years could represent a point of no return for many medium-sized glaciers in the Alps. Some scientific studies already project that, if global warming is not mitigated, two-thirds of the European glacial volume could disappear before 2050.

Ski resorts will have to adapt. An increase in investment in artificial snow production is expected, although this is also limited by ambient temperature and water availability. Furthermore, the business models of alpine resorts could be reconfigured towards mountain tourism less reliant on skiing, promoting summer activities like hiking, cycling, or wellness, and focusing the narrative on natural environment conservation.

Beyond the Alps: Iberian records and tropical nights

The heatwave has also hit Southern Europe hard. In El Granado (Huelva), 46 °C were recorded, the highest temperature in Spain for a month of June since records began. In Mora, Portugal, 46.6 °C were reached, setting a new national record. Even in Germany, minimum temperature records are being broken, with tropical nights preventing thermometers from dropping below 25 °C.

This extreme heat, fueled by warm air masses from the Sahara desert, is revealing the continent's limitations in adapting to increasingly frequent and intense phenomena.