Else Beekman
Every year on 22 March, World Water Day draws attention to the planet’s growing water challenges. In 2025, environmental groups are marking the occasion with a stark warning: save Spain’s glaciers, save the water.
As the planet continues to warm, Spain’s Pyrenees are losing their last glaciers at an alarming rate. And with the ice goes a silent but vital source of fresh water.
Spain’s glaciers are disappearing faster than ever
Back in 1980, Spain still had 39 glaciers in the Pyrenees. Today, only 15 remain, all teetering on the edge of extinction. According to the Pyrenean Institute of Ecology (IPE-CSIC), 93% of Spain’s glacier volume has been lost since 1850. What’s left are fragile, near-stationary ice masses that barely function as water reserves.
The largest of these is the Aneto Glacier, located on the northern slope of Pico Aneto (3,404 metres), the highest peak in the Pyrenees in the province of Huesca, Aragón. Since the 1980s, this glacier has lost more than half its volume and its role as a water buffer has significantly declined.
The decreasing function of water reserves isn’t some distant concern. These glaciers play a crucial role in northern Spain’s water system. They store winter precipitation as ice and gradually release it in spring. Without this natural ‘water vault’, the flow of rivers like the Ebro, Noguera Ribagorçana, Gállego, and Aragón becomes more erratic, just as the country is already grappling with persistent drought and growing water scarcity.
The cryosphere as a climate barometer
Spain’s glaciers are part of what scientists call the cryosphere: all the places on Earth where water exists in frozen forms, such as snow, permafrost, and ice caves. Spain’s cryosphere is especially vulnerable to rising temperatures. While this is true across the globe, Spain’s case is particularly precarious due to its southern latitude, relatively modest mountain heights, and already hot, dry climate. There’s little buffer left to absorb further warming, making the melting process even more rapid. As such, the cryosphere serves as a kind of natural climate clock — the faster it melts, the closer we come to tipping points.
This is painfully clear in the latest climate report from CLIVAR-SPAIN. Not only is glacier surface area shrinking, but the snowline is also shifting higher up the mountains, pushing cold-weather processes out of reach.
World Water Day 2025: water security at risk
The vanishing glaciers are a direct threat to water security across northern Spain. They don’t just supply water, they regulate river flows and act as buffers during extreme droughts. As they decline, Spain becomes increasingly dependent on artificial water storage such as reservoirs. But these too are vulnerable, especially to evaporation and sediment build-up.
Also read: World Climate Day: These climate intervention techniques offer hope
The UN has stressed that protecting glaciers must become a core part of climate and water policy. For Spain, this means investing in smart, flexible water systems which can respond to droughts and floods, along with modern water infrastructure, digital water management, and, above all, long-term political vision.
What can we do to protect Spain’s glaciers?
Glaciers need action. That starts with reducing emissions, but local solutions matter too:
- Reflective covers: In Switzerland, glaciers are partially wrapped in reflective sheeting to deflect sunlight and slow melting. Spain is considering this approach for the Aneto glacier.
- Artificial snow: Used in the Alps to insulate glaciers, but less viable in Spain due to water scarcity.
- Reforestation: Planting trees in mountain areas helps cool the microclimate, retain moisture, and reduce erosion.
- Water management: Smarter use of remaining water through better regulation and reduced waste.
At present, Spain is not taking specific direct measures to protect its glaciers. Instead, the focus remains on broader climate and water strategies, which vary from renewable energy to improved infrastructure.
Also read: Current snow shortage in the Pyrenees will worsen Spain’s water crisis