The glaciers, which function as the last water reserve of Chile, will lose up to 80% of their volume by 2100.
In that scenario, they will only provide half the water they currently supply during droughts.
An international study published in Communications Earth & Environment warns that these ice masses have already lost their capacity to mitigate future megadroughts in the South American country.
Glaciers in Chile are fading: the last defense
The research was led by Chilean Eduardo Muñoz-Castro along with scientists from Switzerland and Austria.
It evaluated how the glaciers of the Southern Andes responded to the megadrought affecting Chile since 2010, and the results project a critical outlook.
“The rise in temperatures in the scenarios projected for the century will lead to glaciers losing more mass than they gain,” explains Álvaro Ayala, from the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL).
The civil engineer Chilean adds: “Steadily throughout the century, they will keep retreating.”

The massive loss of glacier volume
The study by WSL, the Institute of Science and Technology Austria (ISTA), and the Center for Advanced Studies in Arid Zones of Chile establishes alarming projections:
- The large glaciers of the southern Andes will lose between 50% and 80% of their current volume
- The water contribution during summer will be half of the current amount
- The small glaciers will have completely disappeared
“Once the water from the snow fallen in winter and the water stored underground is consumed, the glaciers are like the last reserve in nature,” highlights Ayala.
In particular, their contribution becomes critical at the end of summer, when mountain rivers in Chile reach their minimum flow.
A megadrought that no one predicted
The current water crisis in Chile took the scientific community by surprise.
“The Chilean megadrought was never forecasted in any climate model,” states Francesca Pellicciotti, environmental engineer at ISTA.
Climatologists only realized the severity of the phenomenon in 2015, five years after its onset.
The country faces 15 continuous years of water scarcity, a situation exacerbated by the lack of sufficient saving or consumption management policies.

Desertification advances southward
Ayala recalls that previous studies already warned about a progressive desertification from the north to the south of Chile.
The projections indicate a decrease in precipitation and increase in temperatures that accelerate this process.
Between 2010 and 2019, the glacier flow remained practically unchanged compared to the previous decade.
However, if a new megadrought occurs at the end of the century, the annual and summer flow could decrease by up to 80% compared to levels prior to 2010.
“We found that the water contribution from the glaciers during the summer will be about half of what happened in recent years,” warns the hydrology expert.
Pellicciotti poses a crucial question: “Are we prepared for future climate disasters?”
The results project a weakening of the buffering role of the glaciers against precipitation deficits.
This will increase the water scarcity for ecosystems and livelihoods in the mountainous regions of South America by 2100.
The case of Chile now serves as a reference to analyze similar phenomena in Europe, particularly in the Alps.



