Climate Change Blamed for Nepal's Devastating Glacial Floods, Scientists Warn of More Disasters

Scientists from the World Weather Attribution initiative have identified climate change as a significant factor in the devastating flash floods that occurred in Nepal on August 26. The event, triggered by a massive section of overhanging glacier and rock falling from Lantang Lirung mountain, unleashed a torrent of water, ice, and debris, resulting in over 1,300 deaths and leaving more than 5,000 people missing.

The analysis indicates that climate change contributed to permafrost thaw and glacial thinning, which likely influenced the mountain slope's collapse. Experts warn that this event may foreshadow similar disasters as global temperatures continue to rise.

"Without much faster action to transition to zero fossil fuel emissions we will inevitably see more disasters of this scale occurring in the years to come," said Professor Friederike Otto, Professor of Climate Science at Imperial College London.

Researchers described the incident as a "compound crisis" with multiple contributing factors rather than a single extreme weather event. Decades of atmospheric warming have led to glacial thinning, which has caused the freezing threshold in the high Himalayas to rise by approximately 100 meters per decade. This upward shift exposes permafrost deep within the bedrock to prolonged thaw periods, weakening mountain slopes.

Additionally, a substantial 7.8 magnitude earthquake in 2015 is believed to have potentially preconditioned the slope for failure, though its specific contribution is still under investigation. The researchers also noted that July and August of the year of the disaster were the warmest on record in the region, with heavy snowfall in the preceding months adding significant water volume.

Professor Walter Immerzeel, Mountain Hydrologist at Utrecht University, highlighted the irreversible shifts occurring in Himalayan mountain environments. "Climate change from the burning of fossil fuels is pushing the freezing line – the zero–degree isotherm – upward by roughly 100 metres per decade, exposing perennially frozen ground and bedrock to thaw conditions that are longer and warmer than before," Immerzeel stated. "When you combine high–elevation permafrost degradation with glacier retreat and record summer heat, the structural integrity of these mountain walls is compromised."

The study also points out that even immediate prevention measures may not avert future events, as past warming has already locked in changes in high-altitude permafrost and glaciers, which respond to temperature rises over decades.

Manjeet Dhakal, Director of Climate Analytics South Asia, emphasized the urgency for action. "The magnitude of this disaster is testing Nepal's response capacities and the limits of adaptation. Every fraction of a degree of warming matters," Dhakal said. "Science must now drive urgency: deeper and faster global emission reductions, greater investment in understanding complex mountain risks, strengthened monitoring and early warning, climate-resilient development, and international climate finance support at the scale and speed that frontline countries like Nepal need."