Human-caused climate change likely helped destabilise rock-and-ice slope whose collapse triggered the Aug 26 Nepal-Tibet disaster, first scientific assessment of the deadly event released Thursday found, linking decades of warming to thinning glaciers, thawing permafrost and more rain replacing snow.“There’s absolutely no doubt that human-induced climate change played a role here in the preconditioning of the disaster through permafrost thawing, through thinning of the glaciers, through having more rainfall instead of snow,” said Friederike Otto, climatologist at Imperial College London and co-author of World Weather Attribution (WWA) study.Researchers described it as a cascading disaster rather than conventional flood. Around 2 sq km of rock wall and glacier ice collapsed from Langtang Lirung at about 5,150 metres, plunging around 1,400 metres before turning into a debris flood. Water, rock, ice and sediment then travelled around 22km to Rasuwagadhi in seven minutes, leaving downstream settlements with almost no warning.The study found long-term warming had pushed freezing levels higher and exposed previously frozen rock and permafrost to prolonged thawing, weakening material binding steep slopes. July and Aug were exceptionally warm, with researchers estimating human-caused climate change added around 1.5C to temperatures, while heavy snowfall in late 2025 may have supplied additional meltwater. Nepal’s 2015 magnitude-7.8 earthquake could also have weakened mountain slopes, though researchers could not quantify its role.Priyanka Vadrevu, an independent researcher specialising in climate adaptation and disaster resilience, told TOI, “Rising temperatures are thinning ice, thawing permafrost and weakening frozen material that helps hold steep slopes together. Preparedness in the Himalayas can no longer focus only on rainfall and conventional flood forecasting. We need integrated monitoring of glaciers, permafrost, slopes, rivers and weather conditions.Nepal now hopes to seek around $20 million (£15 million) from UN Fund for Responding to Loss and Damage, which supports countries facing climate-related destruction. The study is expected to strengthen Kathmandu’s case by linking warming to conditions that contributed to slope failure.The findings will also feed into Nepal’s diplomatic push next week. PM Balendra Shah will travel to New York from Sept 22-26 for UN General Assembly — his first foreign trip since taking office — where govt says he will highlight Aug 26 disaster, Nepal’s Himalayan vulnerability and demand greater climate justice and financing for countries bearing disproportionate losses from global warming.
