Scientists forecast a mid-century ‘peak glacier extinction’ as thousands vanish each year

The year a Swiss mountain guide once marked as “the last good season” for his local glacier may now be part of something larger: a global die-off.

A new milestone: “peak glacier extinction”

Scientists have, for the first time, calculated when the planet is expected to reach its maximum rate of glacier disappearance — a mid-century moment they call “peak glacier extinction,” when thousands of individual glaciers are projected to vanish each year.

In a study published Dec. 15, 2025, in Nature Climate Change, an international team led from ETH Zurich reports that the number of glaciers going extinct annually will surge to between 2,000 and 4,000 around the middle of this century, depending on how fast the world cuts greenhouse gas emissions. That is three to five times higher than today’s modeled rate of roughly 750 to 800 glacier extinctions a year.

“For the first time, we’ve put years on when every single glacier on Earth will disappear,” said lead author Lander Van Tricht, a glaciologist affiliated with ETH Zurich and Vrije Universiteit Brussel, in a statement. “Every glacier is tied to a place, a story and people who feel its loss.”

Counting glaciers, not just ice

The team defines peak glacier extinction as the year between now and 2100 when the smoothed global count of glaciers that fall below a minimum size threshold is highest. Unlike most previous work, which focuses on how much ice volume will be lost and how much sea level will rise, this approach counts the disappearance of individual glaciers as discrete events.

Under a scenario where global warming is held to about 1.5°C above preindustrial levels — the more ambitious target in the 2015 Paris climate agreement — the analysis finds that peak glacier extinction occurs around 2041, with close to 2,000 glaciers disappearing each year at that point. If emissions remain high and warming reaches roughly 4°C by 2100, the peak shifts into the mid-2050s, but the toll climbs to as many as 4,000 glaciers a year.

“At the global peak, humanity could lose in a single year as many glaciers as currently exist in the entire European Alps,” the authors write.

How the projections were built

The study draws on three state-of-the-art global glacier models, driven by climate projections from the latest generation of international climate simulations. The researchers use the Randolph Glacier Inventory, a standardized catalog of mountain glaciers worldwide, which lists more than 215,000 glaciers with a combined area of about 705,000 square kilometers.

In their framework, a glacier is considered “extinct” when its surface area shrinks below 0.01 square kilometers — roughly the lower limit of what satellite inventories can reliably track — or when its volume falls to less than 1% of its starting value. Large glaciers that fracture into several pieces are still treated as a single entity for counting purposes, to avoid artificially inflating the number of survivors.

The team then matches model runs to four broad warming pathways: 1.5°C and 2°C, which align with the Paris targets; 2.7°C, roughly in line with current national pledges; and 4°C, representing a high-emissions trajectory.

A surge, then a decline — because fewer glaciers remain

The results show that while glaciers will keep shrinking for many decades, the rate at which they completely disappear does not simply climb steadily. Instead, extinction rates accelerate into mid-century, peak, and then decline as the global glacier population is depleted.

Globally, roughly half of today’s glaciers are projected to survive to 2100 if warming is held near 1.5°C, the study finds — leaving on the order of 100,000 glaciers, mostly at high latitudes and elevations. Under a 2.7°C pathway consistent with current policies, only about 20% would remain. In a 4°C world, fewer than one in 10 of today’s glaciers survive to the end of the century, or roughly 18,000.

“The difference between 2,000 and 4,000 glaciers disappearing per year is determined by emissions in the next few decades,” said co-author Daniel Farinotti, a professor of glaciology at ETH Zurich and the Swiss Federal Institute for Forest, Snow and Landscape Research. “The results underline how urgently ambitious climate action is needed.”

Regions won’t lose glaciers at the same pace

The pattern is not uniform. Regions dominated by small, low-lying glaciers — such as the European Alps, the Caucasus and parts of the subtropical Andes — see extinction peaks early, often before 2040, and lose more than half their glaciers within the next two decades under nearly all scenarios. Areas with massive ice bodies, including the peripheries of Greenland and Antarctica and Arctic archipelagos, respond more slowly, with their own extinction peaks pushed toward the end of the century or beyond.

The Alps, home to some of the world’s most visited glaciers and a dense network of long-term observations, stand out as an early warning.

Central Europe currently counts around 3,000 glaciers. According to the study, the region is likely to hit its local peak glacier extinction between 2033 and 2041 — about a decade before the global peak. By 2100, the number of surviving Alpine glaciers depends sharply on the warming path.

• 1.5°C: about 430 glaciers endure (roughly 12%)
• 2°C: about 270 remain
• 2.7°C (current trajectory): about 110 survive (about 3%)
• 4°C: about 20 survive (around 1%)

“These glaciers are an integral part of Switzerland’s identity and economy,” Farinotti said. “We are looking at a near-total transformation of the Alpine landscape within the lifetime of children alive today.”

Water, hazards — and cultural loss

The consequences extend far beyond tourism and postcard views.

In many mountain regions, glaciers act as natural reservoirs, storing water as ice and releasing melt during dry seasons. This “water tower” function supports drinking supplies, irrigation and hydropower for hundreds of millions of people downstream, from the Andes to the Himalayas to western North America.

Hydrologists have long used the term “peak water” to describe the point at which runoff from a melting glacier reaches a maximum before declining as the glacier shrinks. The new work suggests that in basins dominated by small glaciers, the moment of peak water will often coincide closely with local peaks in glacier extinction. After that, dry-season flows are expected to diminish sharply.

A 2021 assessment by the U.N. Intergovernmental Panel on Climate Change estimated that glaciers worldwide lost more than 6,000 gigatons of mass between 1993 and 2019, contributing about 17 millimeters to global sea level. More recent analyses indicate that glacier mass loss accelerated in the first two decades of this century. A 2025 U.N. report warned that around 1.1 billion people living in mountain regions face growing risks from water stress, floods and landslides linked to the rapid retreat of ice.

As ice pulls back, steep slopes that were once buttressed by glaciers can fail, spawning rockfalls, debris flows and the growth of glacial lakes dammed by loose moraine walls. When such dams give way, the resulting glacial lake outburst floods can sweep away villages and infrastructure downstream in minutes.

The new study does not attempt to quantify those hazards directly, but the authors argue that knowing when regions will see the most rapid loss of their glaciers can help authorities prioritize monitoring and adaptation.

Alongside physical risks, the paper devotes unusual attention to cultural and emotional dimensions.

In parts of the Himalayas and Andes, glaciers are venerated as deities or ancestors. Their disappearance has already prompted new rituals: in 2019, mourners in Iceland held a memorial for Okjökull, the country’s first named glacier lost to climate change, unveiling a plaque that reads, “A letter to the future.” That same year, several hundred people hiked to Switzerland’s Pizol glacier for a ceremony marking its demise. In 2025, a similar event was held for Nepal’s Yala glacier.

Researchers and artists have begun compiling a “Global Glacier Casualty List” and even a “glacier graveyard” to memorialize extinct ice bodies by name and location.

“Glacier loss is not just a statistic,” Van Tricht said. “In many places, it is experienced as bereavement.”

Legal and political ripples

The study’s projections also carry implications for politics and law. Courts in several countries have begun hearing climate liability cases that link specific harms, including glacier melt, to the emissions of large fossil fuel producers. In one prominent case, a Peruvian farmer has sued the German utility RWE in German courts, arguing that its historic emissions contributed to the retreat of glaciers above his hometown and the growth of a lake that threatens to burst.

By putting approximate years on when specific glacier regions are likely to vanish under different warming scenarios, the new work could inform such attribution efforts — though the authors caution that their extinction dates should not be interpreted as precise forecasts for any single glacier.

Glacier counts themselves are also less straightforward than they might appear. Very small or debris-covered ice bodies are hard to detect, and different inventories draw their boundaries in different ways. The authors say the exact numbers are less important than the overall pattern: a pronounced global peak in extinctions around mid-century, and a stark divergence between low- and high-warming futures.

A peak that isn’t a “tipping point”

The paper appears as the United Nations marks 2025 as the International Year of Glaciers’ Preservation and launches a Decade of Action for Cryospheric Sciences, a coordinated effort to improve understanding of ice and snow in the climate system.

It also lands at a moment when governments are under pressure to strengthen their emissions pledges for the 2030s and 2040s. Current policies, if fully implemented, are widely estimated to put the world on track for around 2.7°C of warming by 2100, well above the Paris Agreement’s more ambitious 1.5°C goal.

The authors emphasize that “peak glacier extinction” is not a physical tipping point at which glaciers suddenly destabilize. Instead, it is a statistical turning point in the rate at which named ice bodies disappear from maps and memory.

After that peak, the annual number of extinctions begins to fall — but mostly because there are fewer glaciers left to lose.

“In a sense, the worst year for glaciers is not their last year, but their busiest year of dying,” Van Tricht said. “How high that peak climbs, and how many glaciers remain afterward, is still in our hands.”