On August 26, a glacier slope above the Nepal-Tibet border surrendered to forces long in the making — ice thinned by decades of warming, rock weakened by an earthquake a decade prior, and temperatures running hotter than nature alone would allow. The collapse registered as an earthquake and unleashed floods that killed more than 1,400 people, a toll that now carries a scientific verdict: human-induced climate change helped make this catastrophe possible. As Nepal prepares to carry its grief to the United Nations, the disaster poses an ancient question in a modern register — who bears responsib
Climate change 'absolutely' contributed to Nepal-Tibet glacier collapse floods
More than 1,400 people were killed and thousands are missing following the August 26 floods; thousands of houses were destroyed and energy infrastructure damaged.
Climate change made an unstable situation more unstable.
Mark
So the study says climate change contributed to the collapse. But it also says there were other factors—the 2015 earthquake, the geology of the slope itself. How much of this disaster is actually climate change's fault?
Mimi
That's the wrong question, I think. The study doesn't try to assign a percentage. It says climate change was a destabilizing factor—it warmed the region by 1.5 degrees, thinned the glaciers, created conditions where the slope was more likely to fail. But the slope was already weak. The 2015 earthquake had already damaged it. So climate change didn't cause the collapse in isolation; it made an unstable situation more unstable.
Luke
Right, but we should be precise about what the study actually confirms. It says temperatures were 1.5 degrees warmer due to human influence. It says glaciers are thinning at half a meter per year. But the study itself notes that authorities couldn't confirm the exact impact of the 2015 earthquake on the recent collapse. So there's still uncertainty baked into the causal chain.
Mark
The death toll is over 1,400, with thousands missing. Does the study say anything about whether fewer people would have died if climate change weren't a factor?
Mimi
No. The study is about the physical mechanisms that led to the collapse. It doesn't model counterfactuals—what would have happened in a world without climate change. That's a different kind of analysis, and it's much harder to do.
Luke
And it matters for the policy conversation. We know the disaster happened. We know climate change was one of several factors that made it more likely. But we don't know from this study alone whether reducing emissions would have prevented it, or just made it less likely. Those are different claims.
Mark
Nepal's Prime Minister is going to the UN to talk about climate justice. Is that argument supported by this study?
Mimi
The study supports the factual claim that climate change contributed to a disaster in a country that barely contributes to emissions. Whether that's "unjust" is a values question, not a scientific one. But the facts are there.
Luke
And Nepal is genuinely vulnerable—it's in the Himalayas, it has glaciers, it has steep terrain. So the argument that it's bearing disproportionate risk is sound. The study just shows one concrete example of that risk materializing.
Il Polso
- A glacier above Langtang Lirung collapsed with the force of a magnitude 5.2 earthquake, sending floods and landslides through villages on both sides of the Nepal-Tibet border and killing more than 1,400 people.
- Scientists have now confirmed that climate change — through elevated temperatures, accelerating glacier thinning, and thawing permafrost — directly destabilized the slope before it gave way.
- The disaster was not a single cause but a convergence: a geologically vulnerable mountain, possibly weakened by the 2015 earthquake, pushed past its threshold by warming temperatures and a year of heavy snowmelt.
- Thousands remain missing, thousands of homes are destroyed, and energy infrastructure across the region has been crippled, leaving communities in prolonged crisis.
- Nepal's new Prime Minister is taking the findings to the UN General Assembly, framing the catastrophe as a climate justice issue — a nation among the world's lowest emitters absorbing among its heaviest losses.
On August 26, a glacier slope above the Nepal-Tibet border surrendered to forces long in the making — ice thinned by decades of warming, rock weakened by an earthquake a decade prior, and temperatures running hotter than nature alone would allow. The collapse registered as an earthquake and unleashed floods that killed more than 1,400 people, a toll that now carries a scientific verdict: human-induced climate change helped make this catastrophe possible. As Nepal prepares to carry its grief to the United Nations, the disaster poses an ancient question in a modern register — who bears responsibility when the consequences of collective choices fall upon those least responsible for making them?
On August 26, a glacier slope near Langtang Lirung gave way without warning. The collapse was so violent that seismographs registered it as a magnitude 5.2 earthquake. Floods and landslides followed, tearing through border towns and villages in Nepal and Tibet, destroying thousands of homes, damaging energy infrastructure, and killing more than 1,400 people. Thousands more remain missing.
A study published this week by the World Weather Attribution group has confirmed what many feared: climate change was a direct contributor. Climatologist Friederike Otto of Imperial College London stated there was "absolutely no doubt" that human-induced warming had preconditioned the disaster. The researchers describe it as a compound event — a convergence of destabilizing forces arriving at the same place at the same time.
Those forces included temperatures running 1.5 degrees Celsius above what they would have been without human influence, glaciers thinning at roughly half a meter per year, and heavy snowfall from the previous autumn generating large volumes of meltwater. Mountain hydrologist Walter Immerzeel also pointed to the 2015 magnitude 7.8 earthquake, which may have weakened the rock beneath the glacier long before this year's collapse.
The study is careful to note that climate change was not the sole cause — rather, it acted as a destabilizing force on a mountain already geologically fragile. The slope was vulnerable. Warming made it more so.
Nepal's government has drawn a pointed conclusion from the findings. The country contributes almost nothing to global greenhouse gas emissions yet ranks among the most exposed nations on Earth to climate impacts. Prime Minister Balendra Shah is set to address the United Nations General Assembly in New York to press the case for climate justice — the principle that those least responsible for the crisis should not be left to bear its heaviest costs alone.
On August 26, a glacier slope near the peak of Langtang Lirung, a mountain on Nepal's side of the Himalayas, gave way. The collapse was sudden and violent—the massive chunk of ice and rock struck the valley floor with such force that seismographs recorded it as a magnitude 5.2 earthquake. What followed was catastrophic: floods and landslides swept through border towns and villages in Nepal and Tibet, destroying thousands of houses, crippling energy infrastructure, and leaving more than 1,400 people dead. Thousands more remain missing.
A new study published this week by the World Weather Attribution group has now confirmed what many suspected: climate change played a direct role in making the disaster possible. Friederike Otto, a climatologist at Imperial College London and one of the study's authors, stated plainly that there was "absolutely no doubt that human-induced climate change played a role here in the preconditioning of the disaster." The research describes the event as a "compound event"—not a single cause, but a convergence of destabilizing factors that came together in the same place at the same time.
The study identifies several interlocking conditions. In July and August, temperatures in the region ran approximately 1.5 degrees Celsius warmer than they would have been without human influence on the climate. Glaciers in the area have been thinning at roughly half a meter per year, a process that weakens existing fractures and increases instability in the ice mass. Heavy snowfall in October and November of the previous year had also accumulated, creating a large volume of meltwater that began flowing through the system in the early months of the year. These factors, the researchers suggest, may have interacted to amplify the compound event.
But the story is older than this year. A magnitude 7.8 earthquake that struck the region in 2015 may have weakened the underlying rock mass beneath the glacier, though authorities have not been able to confirm the precise extent of that earthquake's impact on the recent collapse. Walter Immerzeel, a mountain hydrologist at Utrecht University and another co-author of the study, described the slope as "geologically vulnerable"—potentially weakened by the 2015 quake and then destabilized further by the ongoing retreat of glaciers and permafrost.
The World Weather Attribution study is careful to note that climate change was not the sole cause of the disaster. Rather, it functioned as a "destabilising factor acting on a pre-existing geological predisposition." The mountain was already fragile. Climate change made it more fragile still.
In the aftermath, Nepal's government has seized on the findings to make a broader argument about global inequality. The country contributes among the lowest amounts of greenhouse gas emissions globally, yet it ranks among the most vulnerable places on Earth to the effects of warming. Balendra Shah, who recently became Prime Minister of Nepal, is scheduled to appear at the United Nations General Assembly in New York next week to discuss the disaster and to press the case for climate justice—the principle that nations least responsible for emissions should not bear the heaviest burden of their consequences.
Citazioni salienti
There was absolutely no doubt that human-induced climate change played a role here in the preconditioning of the disaster.— Friederike Otto, climatologist at Imperial College London
The slope was geologically vulnerable, potentially weakened by the 2015 earthquake and destabilized further by glacier and permafrost retreat.— Walter Immerzeel, mountain hydrologist at Utrecht University
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