Chile’s glaciers are dying. You can actually hear it.

“I am the guardian of the glacier,” says Andrea Carretta. He does not mean this as a boast but rather a simple acknowledgment of service. The 46-year-old park ranger slowly lowers himself until he is on one knee. In quiet tones he asks the glacier for permission to lead us onto the secluded ice.

We’re at the approach to the Exploradores Glacier, situated in southern Chile’s Laguna San Rafael National Park. It’s early September, a season of less rain and fewer tourists. Swollen gray clouds loom over us as the dense forest recedes. We strap crampons onto our hiking boots and crunch our way through a terrain of slick morainal sediment that suddenly cascades into a swirling panorama of pale blue ice massifs and minty glacial waterways. The primordial might of Exploradores must be respected, even by someone like Carretta who visits the glacier on foot daily, often spending evenings at its edge in a firelit cabin bedroom where he dines on canned food. As a new visitor, I find the glacier beautiful but also terrifying, as with any indomitable force.

It’s a bit jolting, then, to hear Carretta say, “The glacier is dying.” The words are both tender and factual. Born in the Italian Alps, an accomplished but wayward mountain climber, Carretta found his paradise in Patagonia in 2016. He relocated to Chile with his wife and son, who accept how his heart is divided. “I know the glacier loves me,” he says.

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Today it is his lot to measure with sensors the steady recession of the glacier, about a yard every year. It’s there for Carretta to see. Where there was ice, now there are ponds. There is no mystery here. The melting of Patagonia’s glaciers coincides with rising temperatures that, in turn, correlate with the past half century’s acceleration of carbon emissions.

“The tourists who come here for a beautiful photo, I say to them, ‘Take your photo, and then come back in five years and take another, so that you can see the difference the way I see it,’ ” he says. “Maybe there’s hope. Or maybe the Earth will just punish us.”

As world-famous as Chilean Patagonia is, though, its extravagance lies in its lack of polish. Here nature—hushed, magisterial—is luxury enough. The region’s 775-mile north-south byway, the Carretera Austral, winds through the snow-draped Andean mountain chain and pastures, betraying only the vaguest evidence of human habitation, such as the odd cowboy on horseback flanked by his tribe of cattle dogs. With the exception of urban Coyhaique, the towns of Chilean Patagonia do not stray from the territory’s rough-hewn ethos. Its people are synchronized with the land rather than with greater civilization. The common adage here is, “He who rushes in Patagonia loses time.”

Patagonia’s approximately 17,300 glaciers, strewn across Argentina and Chile’s Southern and Northern Ice Fields, symbolize the region above all else. Relics of an ice sheet that peaked in size some 28,000 years ago, they constitute the establishing shot for the region’s seeming immutability. And, like the rest of Patagonia, the glaciers reward inspection. Each undulating ice sculpture is different from the other. But like all glaciers, their growth or decline is reliant on the amount of snow they receive and the temperatures that either keep them frozen or speed their thawing and calving.

Key to appreciating their character is recognizing their vulnerability. “It’s like nature’s thermometer,” says Jorge O’Kuinghttons Villena, the Chilean government’s chief glaciologist in the Patagonian region. “When you see it recede, you know that human lives nearby are at risk.”

O’Kuinghttons is referring to the fact that melting ice can result in glacial lake outburst floods, or GLOFs, that can swiftly overtake a nearby community. A striking case of this occurred in 1977, at Bahía Murta, a rural town on the shore of General Carrera Lake that was engulfed by surging glacial flows.

“Many people were taken by surprise, because it was a sunny day with no rain,” recalls Clotilda Yanez Avilles, whose family had already relocated with other townspeople after scientists warned of the ominous rise of the two rivers surrounding Bahía Murta. “Some people didn’t want to abandon their homes and had to be rescued by boat.”

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I ask O’Kuinghttons if the GLOF that destroyed Bahía Murta was a once-in-a-lifetime occurrence. “No, that was an extreme event,” he replies. “And those will happen more frequently in Patagonia, and with more violent intensity.”

One early morning, we drive southward from the ramshackle town of Puerto Río Tranquilo, veering off onto a bumpy dirt road astride the Leones River and moving through private forestland until we arrive at an unpaved parking area.

Our guides, Pascual and Anita Diaz, married and in their 50s, then lead us on a three-hour hike to the Leones Glacier. Sloshing across streams, weaving through forestland that had been thinned out by a GLOF two decades earlier, scaling a precarious wooden cliffside ladder, and then navigating an even more precarious wooden footbridge, we at last make our way across a rocky plain that dwindles into a morainal shoreline of a vast glacial lake. 

A lone boat, owned by the Diazes, sits lashed to the boulders. We skim across the still surface of Leones Lake for its entire six-mile length, until we dead-end at the foot of the glacier at the eastern edge of the Northern Patagonian Ice Field.

Owing to the remoteness of Leones Glacier, only a few hundred tourists visit it each year, a tiny fraction of the traffic seen at Exploradores. Leones’s facade is like that of a frostbitten old man: unkempt, scarred, and hued with a lifetime’s complexities. For a full hour, I contemplate it. 

Floating on the otherwise empty lake—and then later, picnicking on the boulder slabs of the glacier itself—I experience an almost monastic sensation. No life, no movement, no change of any sort, other than the slow ebbing of sunlight that by late afternoon casts the landscape in a daguerreotype luster. Every 10 minutes or so, the deep silence gives way to a sound akin to gunfire: the cracking of ice, the concussion as the glacier’s weighty particles crash into the water. Just as suddenly, silence returns.

This is a casual, everyday occurrence, says Pascual Diaz. What alarms him, he adds, is that the glacier’s slow but steady recession over the past two decades has begun to accelerate.

“In these last five years,” he says, “I can see the changes very easily.” Gesturing to the other side of the lake, Diaz cites the brownish morainal sediment as all that remains of a glacial surface from just a couple of years ago. Like Andrea Carretta at Exploradores, Diaz regards Leones with palpable helplessness.

“All I can do is show what is happening,” he laments.

My interpreter and I continue on the Carretera Austral in the direction of the southern Andes, with the lavishly frothing Baker River to our right and amply fed cattle preening all around. We pull into a large parking lot haloed by food stores and tourist booths. Then we descend on foot along a labyrinthine succession of wooden stairs and boardwalks into Tortel, a 68-year-old village on stilts.

Some 500 residents dwell in cabins suspended by wooden beams over an outflow to the Pacific Ocean, representing a kind of apogee in the practice of living dangerously in Chilean Patagonia. Sandwiched between the Southern Ice Field and the San Rafael Glacier at the mouth of the Baker River, Tortel feels very much like civilization’s terminus. 

There are no cars. Electricity is sporadic; firewood is the village’s main source of heating. But for the many young people whose wanderlust has led them from urban malaise to the rugged tranquility of the glacial outback, living at the brink of the icy wilderness is the point.

“The reason I decided to relocate here from Santiago,” says 26-year-old Freddy Fernandez Cardenas, a former physical education instructor who now operates one of Tortel’s two water taxi services, “is that here, when I close my eyes and then open them, what I see are mountains and water.”

In a blue house on a steep, tree-shrouded hill I meet one of Tortel’s first inhabitants, 84-year-old Juanita Vidal Menco, among whose 13 offspring is the village’s mayor. “There was nothing here,” she says, recalling when she arrived at the age of 10 with her family on horseback from the larger, snowier town of Cochrane, due north. They and other cattle-raising families lived in tents while chopping down trees to construct Tortel’s boardwalks. 

At the age of 16, after Tortel’s first houses were built, she married a man 10 years her senior who was already imagining new frontiers. “He thought it would be better to raise cattle on the prairie near the San Rafael Glacier,” she says. “So we built a house and lived there for several years.” Fondly, the old woman adds, “We lived like animals, with no concept of time or memory.”

The couple eventually moved back to Tortel to raise their family, a decision that would prove wise, as rising temperatures would lead to the glacier’s retreat and, with it, the flooding of nearby lakes and rivers. In April of 2008, a GLOF—the first of what would be seven in the Baker River Delta over a two-year period—engulfed the entire area.

The village was spared, but one look at Tortel’s rickety positioning is all it takes to recognize its ongoing state of peril. “Being so near the glacial activity,” says O’Kuinghttons, “puts Tortel in real danger, right now.”

For travelers, it is a sobering notion to seek out nature’s undying primacy, only to discover that even its mightiest exemplars are mortal in their own way.

Months after my time in Chilean Patagonia, I would find myself lying in the comfort of my bed and thinking about the night I spent in a tent on the shore of Leones Lake, listening to the faint popping from the campfire and the incantation of a distant glacial waterfall. Then, piercing the semihushed soundtrack, would come the unmistakable sound of fracturing ice, followed by the detonation of the lake’s surface—and after that, the near-stillness. The cycle would then resume. I fell asleep to it.

Now, it keeps me awake.