When I visited the Perito Moreno glacier in 2013, it was one of the few glaciers in the Americas, and in the world, that was not retreating. It was stable and in some years expanding. That’s no longer the case, as this Copernicus Sentinel-2 Satellite image, acquired on 30 June 2026, illustrates.

The image shows the glacier’s broad ice front between Lago Argentino and Brazo Rico, a southern arm of the lake. The red line marks the ice front’s position in 2016, showing how far the ice moved back over the past decade.

Studies released in July 2025 showed that Perito Moreno had lost 1.92 square kilometres of ice cover over the seven previous years, and that its thickness is decreasing by up to eight meters, about 26 feet, a year. From a Guardian report:

Dr Lucas Ruiz, a glaciologist at the Argentine Institute of Nivology, Glaciology and Environmental Sciences, said: “The Perito Moreno is a very particular, exceptional glacier. Since records began, it stood out to the first explorers in the late 19th century because it showed no signs of retreat – on the contrary, it was advancing. And it continued to do so until 2018, when we began to see a different behaviour. Since then, its mass loss has become increasingly rapid.”

Scientists and local guides warn that the balance is beginning to shift. “The first year the glacier didn’t return to its previous year’s position was 2022. The same happened in 2023, again in 2024, and now in 2025. The truth is, the retreat continues. The glacier keeps thinning, especially along its northern margin,” said Ruiz. This sector is the farthest from tourist walkways and lies above the deepest part of Lago Argentino, the largest freshwater lake in Argentina.

Further on, Ruiz explains why:

“Perito Moreno’s size no longer matches the current climate; it’s simply too big. It can’t withstand the heat, and the current ice input isn’t enough to compensate,” Ruiz said.

Ice that once rested on the lakebed owing to its weight, said Ruiz, had now thinned so much that it was beginning to float, as water pressure overtook the ice’s own.

With that anchor lost, the glacier’s front accelerates – not because of increased mass input from the accumulation zone, where snow compacts into ice, but because the front slides and deforms. This movement triggers a feedback loop that further weakens the structure, making the process potentially irreversible.

The glacier, which sits in Los Glaciers National Park in Argentina’s Santa Cruz Province, is one of the most important attractions in Argentine Patagonia, visited by more than 600,000 people annually.

As illustrated by the lead photo at top, showing a large chunk of ice breaking from its front, the glacier is a non-stop sensory spectacle in a visually stunning landscape of whites and blues supported by an equally compelling soundtrack of cracks, breaks, splashes and crashes, served up in all-natural surround sound. At times it seemed ethereally other-worldly.

When that chunk crashed through the still water of the Canal de los Témpanos (Iceberg Channel), the wake it produced was large enough to topple small boats. Which is why none are allowed nearby. In the four hours I was there, I saw at least half a dozen calvings and several smaller breaks. All were humbling and unforgettable experiences.

At nearly 30 kilometers (19 miles) in length and covering 250 square km, Perito Moreno is Argentina’s third largest glacier, and one of 48 glaciers fed by the Southern Patagonian Ice Field, the world’s third largest reserve of fresh water.

In April, Argentina’s Congress passed a controversial amendment, championed by far right-wing president Javier Millei, to a 2010 Glacier Law, that prohibited all mining and exploration activities in glacier regions, to now make it easier to mine in glacier regions, threatening crucial water resources.

Fifty-one more images from my 2013 visit, beginning with six that captured some of those crack, breaks crashes and splashes.

And a few more from the park grounds itself.

Photos from 9 February, 2013.