The sudden and fast recoil of expert Moreno, one of the few stable glaciers of Argentine Patagonia

A woman observes the Expert Moreno glacier. — Photo foot, A scientific study has concluded that the disappearance of the most famous glacier in Argentina is probably irreversible.

- Author, Neil glasses
- Author's title, The Conversation*
August 15, 2025

The Perito Moreno glacier was once considered a rarity: one of the only stable glaciers in Patagonia. However, scientists have discovered that he suffers a sudden and probably irreversible setback, and this collapse is a warning for the rest of the ice in the world.

The Moreno Expert is unusually accessible for such a large and spectacular glacier, and receives about 700,000 visitors a year

Fed by abundant snowfall at the top of the Andes, the glacier descends through Bean forests until ending in Lake Argentino.

From here, tourists can approach and observe closely from an observation platform specially built for this purpose how the icebergs detach from the front of the glacier, a process called detachment. The icebergs regularly cracks and falls into the turquoise lake underneath.

But now all this is on the verge of disappearing.

While 90% of Patagonia's glaciers decrease, Expert Moreno has long been the exception thanks to its unique location.

The glacier leads to a narrow channel of the Argentine Lake, where sometimes it advances enough to completely block one of the arms of the lake.

This forms a natural ice dam that cuts the flow of water and makes it accumulate behind it. When the water pressure is too large, the dam is broken.

These ruptures usually occur every few years, but it is impossible to predict when.

The glacier has remained stable so far and has not been reduced because it ends in relatively shallow waters, where it clashes with the opposite shore.

But all this is about to change, since years of reduction of the warmest snowfall and summers have weakened the glacier.

A team of scientists from Germany and Argentina has tracked their changes over time, and has used satellite data, radars mounted into helicopters and maps of the lake bed to predict their future behavior.

A quick withdrawal

In a new study published in the magazine Communications Earth & Environmentscientists report that the surface of the glacier has decreased dramatically in recent years and is now going back faster, while ice flows faster.

They believe that the Perito Moreno glacier will never move towards the opposite shore of the lake.

Pieces of ice detached from expert Moreno over the waters of the lake with which he communicates. — Photo foot, Experts believe that the expert Moreno will never advance to the opposite shore of the lake.

Instead, it is forecast that it will continue to retreat more and more in the lake, encountering increasingly deep waters, which will accelerate its collapse.

This is because glaciers detach more rapidly in deep water. The authors predict that the front of the glacier will soon begin to float, which will make it even more unstable.

The glacier is entering a very fast and probably irreversible setback phase.

The tourists may see more dramatic detachments in the short term, but what they will actually witness is the slow disappearance of one of the most emblematic natural wonders of Patagonia.

Over time, they will be unable to see the glacier, since it will go back to the mountains.

The worldwide decline of glaciers

The recoil of Expert Moreno will represent more than losing a beautiful photo for tourists: it is a symptom of what is happening to mountain glaciers worldwide.

Glaciers are melting faster than ever. Since 2000, mountain glaciers have lost more than 6,500 billion tons, or 5%, their ice. In Iceland, funerals have even been held due to the death of glaciers.

As these glaciers melt, they return their fresh water reserves to the oceans, which raises sea level. If they melt completely, they would raise the global sea level in 32 cm.

We are far from that point, but this means that people living along the coast will probably feel the impact of glaciers melting.

The effects will also feel inland. As the glaciers go back, they can cause mass floods, since the lakes damaged behind the ice and their Morana dams are suddenly empty when the natural dam is broken.

These called floods due to the overflow of glacier lakes are a growing threat to 15 million people worldwide.

A destroyed and mud covered prey after the flood caused by melting a glacier. — Photo foot, Glaciers can cause flooding, which is a threat to millions of people in the world.

Other catastrophic events can be linked directly to changes in glaciers.

For example, in May 2025, the Birch glacier in Switzerland collapsed when a piece of a nearby mountain detached and fell on the ice. The resulting avalanche completely destroyed the Blatten village.

In cases like these, exhaustive monitoring and early evacuation save lives.

There are other human consequences related to the water supply.

Glaciers act as natural freshwater reservoirs, storing winter snow and releasing melted water throughout the year.

Hundreds of millions of people depend on them to obtain drinking water, for agriculture and sanitation. When the glaciers disappear, so does that constant water supply.

The perspective of the disappearance of the Perito Moreno glacier is not just a problem for Patagonia. It is a warning of what awaits us with the rest of the glaciers of the world.

* Neil Glasser is a physical geography professor at Aberystwyth University in Wales. This article was originally published in The Conversation and we reproduced it under the Creative Commons license. Click here To read the original version.