High-altitude glacier collapse in Nepal triggered mudslide

BEIJING, Aug. 28, 2026 /PRNewswire/ -- The following article was published today by China Daily.

The deadly mudslide that swept through a major China-Nepal border crossing was triggered by a high-altitude glacier collapse in Nepal, China's Ministry of Natural Resources said on Thursday, highlighting the growing risks posed by unstable mountain environments as the climate warms.

The disaster occurred on Wednesday morning on the Nepal side of the border, sending a torrent of ice, rocks and debris toward Gyirong Port in Gyirong county, a major land crossing linking China and Nepal in Shigatse, Xizang autonomous region.

The disaster caused heavy casualties and left hundreds missing in China and Nepal.

According to the ministry, the disaster began with a high-altitude glacier collapse in Nepal. The falling ice and rock traveled rapidly down a mountain slope, scouring loose glacial debris along its path and developing into a debris flow before entering the Gyirong Zangbo River and becoming a mudslide.

The flow then struck facilities at Gyirong Port before continuing downstream toward Nepal, said Guo Zhaocheng, director of the geological disaster investigation and monitoring center at the China Aero Geophysical Survey and Remote Sensing Center for Natural Resources.

The debris flow generated by the glacier collapse traveled at about 50 meters per second. The extreme speed left people little time to react and allowed the flow to affect an area more than 20 kilometers from its source, contributing to the heavy losses, the ministry said.

The combination of ice, water, loose rock and steep slopes can make high-altitude disasters particularly fast-moving and difficult to predict, experts said.

"If an ice-rock avalanche can be detected upstream, it is theoretically possible to provide downstream communities with about 20 minutes of warning," said Kang Shichang, director of the Institute of Mountain Hazards and Environment at the Chinese Academy of Sciences in Chengdu, Sichuan province.

But the disaster occurred in a remote Himalayan area characterized by deep valleys and high mountains, where monitoring infrastructure is limited. The floodwater also reached the border rapidly, further shortening the available warning time, Kang said.

The disaster highlights a concern that climate change is reshaping the hazards of the Qinghai-Tibet Plateau and surrounding mountains.

Du Jun, director of the climate center of the Xizang regional meteorological bureau, said global warming is driving changes in glaciers, permafrost and snowfall that can increase the frequency and complexity of high-altitude disasters.

Glacier retreat can expand glacial lakes and increase the volume of water they hold, raising the risk of glacial lake outburst floods. "It also exposes more loose glacial debris, increasing the amount of material available to mudslides, while greater meltwater can strengthen erosion and the capacity of rivers to transport debris," Du told China Daily.

At the same time, permafrost degradation weakens slopes and foundations, and changes in groundwater and runoff can intensify erosion.

In southern Xizang, the number of snow-cover days has declined significantly since 1981, falling by an average of 12.36 days every decade, according to Du.

A shorter snow-cover season can alter the timing and intensity of spring snowmelt, while reducing the buffering effect of snow cover and increasing erosion, he said.

Multiple changes can overlap in both time and space, with glacier melt, permafrost degradation and heavy runoff interacting across different elevations. "The result is a shift in highland disasters from isolated events toward more frequent, cascading and interconnected disasters," Du said.

The Qinghai-Tibet Plateau has already experienced rapid warming and wetting. From 1961 to 2022, average temperatures across the plateau rose by about 0.37 C per decade, faster than the global and national averages, while average precipitation increased by 9.4 millimeters per decade. Satellite observations show that the plateau's glacier area shrank by about 18 percent from 1985 to 2020, from roughly 83,000 to 68,000 square kilometers, according to the China Meteorological Administration.

Zhang Xingying, a member of the 14th National Committee of the Chinese People's Political Consultative Conference and an official with the China Meteorological Administration, warned during China's annual two sessions in 2025 that glacier surges, ice avalanches and glacial lake outburst floods could become more frequent as glaciers melt.

"The risks of glacier-related mudslides, major disasters and catastrophes could also increase," he said.

Zhang has called for a monitoring system integrating ground, air and satellite observations across the plateau and surrounding areas, as well as stronger research into glacier-related disaster mechanisms and improved forecasting and risk assessment.

Li Menghan contributed to this story.

SOURCE China Daily