More than 900 people have now been confirmed dead and over 3000 are still missing following a glacier collapse on the Nepal-Tibet border.

More than 800 people are now known to have died and more than 3000 are still missing following a glacier collapse on the border between Nepal and Tibet on Wednesday 26 August 2026. The incident was first recorded as a Magnitude 4.4 Earthquake by the United States Geological Survey at 2.52 am GMT, which is 8.37 am in Nepal and 10.52 am in Tibet (Tibet has been part of China since the 1950s, and China uses a single time-zone for all its territory, leading to a two-and-a-half hour time gap between Tibet and Nepal, despite their having a similar longitude), a figure which was revised to a Magnitude 5.2 event shortly after. Seven minutes after this a flash flood and debris flow hit the Gyirong Port border crossing between Nepal and Tibet, before passing along the Lhende Khola River Valley in Nepal and into the Trishuli River system.

CCTV footage of a flash flood and debris flow hit the Gyirong Port border crossing between Nepal and Tibet on Wednesday 26 August 2026. Hong Kong Standard.

This event was initially interpreted as an Earthquake-induced glacier collapse, probably caused by a glacier shattering and releasing a melt-lake which had built up behind it. Such events are the most common form of glacier collapse, and are particularly associated with warming global temperatures. Essentially, glaciers begin to melt behind their leading edge, with the amount of ice in front of the growing lake slowly decreasing till the whole edifice collapses. However satellite images taken in the days before the collapse revealed no such lake, and it is now thought that a chunk of glacier with an area of about 200 000 m², and a volume of 1-2 million m³, broke off a glacier at an altitude of between 5200  m and 5400 m above sealevel, then dropped vertically about 1200 m into the valley below. This impact caused the event which the United States Geological Survey interpreted as an Earthquake.

CCTV footage of a debris flow hitting the Gyrong Port Border Crossing on Wednesday 26 August 2026. Resonoud News (响亮新闻)/Wikimedia Commons.

Approximately seven minutes after this initial collapse, the Gyirong Port Border Crossing was hit by a flood and debris flow 80 m high, travelling at approximately 180 km per hour (50 m per second). This remarkable velocity was driven largely by the steep nature of the high mountain valleys, with the Gyirong Port border crossing being approximately 3000 m lower than the initial impact point of the falling glacier. The debris flow continued down the valley for approximately 100 km, sweeping away 41 bridges and 42 km of road, as well as the Gyirong Port border crossing in Tibet and the corresponding Rasuwagadhi Customs Office in Nepal, as well as numerous homes and other buildings, and causing significant damage to six hydroelectric projects in Nepal. Bodies of victims of this flood event have been found as far away as Uttar Pradesh in northern India, more than 250 km from the initial glacier collapse event.

The remains of a bridge in Nepal swept away by the 26 August 2026 floods. Ritesh Shukla/Getty Images.

Glacier collapses are a part of the natural cycle of events within the Himalayas. The mountains here are not static, but are actively growing as the northward movement of the Indian Plate pushes up the overlying Eurasian plate. This means that glaciers which sit upon these mountains are slowly raised to ever higher altitudes, while at the same time becoming ever more steeply inclined. Eventually, this situation becomes unstable, and gravity overcomes the ability of the ice to stick to the underlying rocks, causing sections of glacier to collapse down the sides of the mountains.

Block diagram showing how the impact of the Indian Plate into Eurasia is causing uplift on the Tibetan Plateau. Jayne Doucette/Woods Hole Oceanographic Institution.

This situation is made significantly worse by rising global temperatures, with the Himalayan region warming at twice the global average, which lead to higher rates of melting on glaciers in the Himalayas. The problem here is not just that the ice melts, but that when it does the water tends to percolate downward through any cracks or holes in the glacier surface, eventually pooling on the underside of the glacier. This creates a layer of liquid water over which the glacier can flow, which is the natural way in which glaciers move in lowland areas, but can lead to catastrophic consequences on high, steeply inclined glaciers.

This warming does not just threaten glaciers in these regions; many of the highest mountains are effectively rubble piles held together by ice and frozen soil (permafrost). As the Himalayas warm this ice can thaw, leading to parts of mountains breaking away, leading to more and larger landslides and rockfalls in an area where these are already a major threat to both lives and infrastructure. 

Rescue efforts following the 26 August event have been greatly impacted by the loss of roads and bridges, as well as the large amounts of mud and silt left behind by the floods. Rescue workers have often had to wade through deep mud to reach communities cut off by the floods, with other communities only accessible by helicopter. 

Floodwaters and debris passing through a community in Nepal on Wednesday 26 August 2026. Safal Prakash Shrestha/JNA Press/ZUMA Press/Shutterstock.

Concerns were raised about a second flood hitting the area on Thursday 27 August, after Chinese authorities discovered a barrier lake which had formed behind debris deposited at the confluence of the Chhochen Khola and Purepu Tsangpo rivers in Tibet. At the time, there was an estimated three million cubic metres of water in this lake, which had begun to overtop the barrier, leading to fears of an imminent collapse. However, this lake subsequently drained away naturally without Human interference, and had largely disappeared by Sunday 30 August. 

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Seven known deaths following avalanche on Mount Yalung Ri, Nepal.

Seven people are known to have died and another four are missing following an avalanche on Mount Yalung Ri in the Rolwaling Himal Mountain Range (part of the Wider Himalayas) in east-central Nepal, close to the Tibetan border. The event happened at about 8.30 am local time on Monday 3 November 2025, shortly after the party had left a base camp at 4900 m to ascend the 5630 m peak. The known dead comprise two Nepalese mountain guides, plus five foreign tourists, two Italians, a Canadian, a German, and a Frenchman. Four more Nepalese mountain guides, and another two French tourists (one of whom is understood to have been the wife of the deceased French national) survived, but had to be airlifted to a hospital in Kathmandu to be treated for a variety of injuries. All four of the missing climbers are described as experienced Nepalese mountain guides, familiar with high-altitude conditions.

The location of Yalung Ri. Google Maps.

Avalanches are caused by the mechanical failure of snowpacks; essentially when the weight of the snow above a certain point exceeds the carrying capacity of the snow at that point to support its weight. This can happen for two reasons, because more snow falls upslope, causing the weight to rise, or because snow begins to melt downslope, causing the carrying capacity to fall. Avalanches may also be triggered by other events, such as Earthquakes or rockfalls. Contrary to what is often seen in films and on television, avalanches are not usually triggered by loud noises. Because snow forms layers, with each layer typically occurring due to a different snowfall, and having different physical properties, multiple avalanches can occur at the same spot, with the failure of a weaker layer losing to the loss of the snow above it, but other layers below left in place - to potentially fail later.

Diagrammatic representation of an avalanche, showing how layering of snow contributes to these events. Expedition Earth.

Yalung Ri is generally considered to be a 'safe' mountain for inexperienced climbers, and the team hit by the avalanche had been scaling it as part of a training exercise ahead of an attempt on the more challenging, 6334 m Dorma Kang. However, Nepal has been hit by particularly high snowfalls this autumn, linked to Cyclone Montha, which hit the coast of Andhra Pradesh, India, on Tuesday 28 October. This has led to a series of snowfall related events, and has led many high-altitude communities in Nepal to move to lower locations temporarily. One of the surviving tourists on Yalung Ri has complained that, despite calling for help, rescue workers did not reach them till some time after the avalanche, something which rescue workers have attributed to poor weather conditions, which prevented a helicopter from approaching the mountain.

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At least 65 dead in Nepal and India amid flooding and landslides.

At least 65 people have died in a series of flooding and landslide events in Nepal and India since Friday 3 October 2025. The majority of the deaths have occurred in the Ilam District of Nepal, where 37 people have died in a series of landslide events, with many more still missing. At least eight more people have been killed in floods, landslides, and lightning strikes elsewhere in Nepal. In India, at least 20 people have died in flash floods and landslips in the Darjeeling District of West Bengal, which borders onto Ilam District in Nepal.

A landslide in Ilam District, Nepal, which occurred on Saturday 4 October 2025. National Disaster Risk Reduction and Management Authority.

The events are associated with heavy rains caused by an ongoing Monsoon Season in Nepal, which typically begins in June and ends around the middle of September. The annual monsoon in Nepal claims a large number of lives each year, and late rains such as these bring with them additional problems, as by September the ground in low lying areas of Nepal is often waterlogged, and the waters rivers and lakes high, if not actually overflowing. This means that even if the rains stop soon, their effects are likely to be felt for some time yet. Sadly, while late rains were once a rare event, they are becoming more common as a result of global warming, which is resulting in a hotter, wetter climate in the region.

Monsoons are tropical sea breezes triggered by heating of the land during the warmer part of the year (summer). Both the land and sea are warmed by the Sun, but the land has a lower ability to absorb heat, radiating it back so that the air above landmasses becomes significantly warmer than that over the sea, causing the air above the land to rise and drawing in water from over the sea; since this has also been warmed it carries a high evaporated water content, and brings with it heavy rainfall. In the tropical dry season, the situation is reversed, as the air over the land cools more rapidly with the seasons, leading to warmer air over the sea, and thus breezes moving from the shore to the sea (where air is rising more rapidly) and a drying of the climate. This situation is particularly intense in South Asia, due to the presence of the Himalayas. High mountain ranges tend to force winds hitting them upwards, which amplifies the South Asian Summer Monsoon, with higher winds leading to more upward air movement, thus drawing in further air from the sea.

Diagrammatic representation of wind and rainfall patterns in a tropical monsoon climate. Geosciences/University of Arizona.

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At least 148 dead amid flooding and landslides in Nepal.

At least 148 people have died and more than fifty are still missing in a series of flood and landslide events which hit Nepal driven by heavy rains which have fallen across the country since Friday 27 September 2024. The worst of the flooding has occurred in the densely populated Kathmandu Valley in the central part of the country, where 322 mm of rain fell within 24 hours between Friday and Saturday mornings, the largest amount of rain ever recorded within 24 hours in Nepal.

Flooding on the Bagmati River in Kathmandu on Saturday 28 September 2024. Anadolu Ajansi/Getty Images.

Thirty four people are known have died in Kathmandu, and at least 35 more in a series of landslides on the Prithvi Highway, outside the city, which buried two busses and several other vehicles. In the city Bhaktapur, 15 km to the east of Kathmandu, five people, including a pregnant woman and a four-year-old girl died when a house collapsed, and six people died when a landslide hit the All Nepal Football Association's training centre in Makwanpur. 

Flooding in Lalitpur, to the south of Kathmandu, on 28 September 2024. Gopen Rai/Nepal Times.

The annual monsoon in Nepal claims a large number of lives each year, with at least 170 known to have died this year between the onset of the monsoon season in June and the onset of Friday's rains. However, this rainfall typically ends towards the middle of September. This year's extended monsoon is thought to have been caused by a low pressure system over India, in turn caused by this year's exceptionally high global temperatures. Late rains such as these bring with them additional problems, as by September the ground in lowlying areas of Nepal is often waterlogged, and the waters rivers and lakes high, if not actually overflowing. This means that even if the rains stop soon, their effects are likely to be felt for some time yet, with the waters in the Koshi River recorded as running at a rate of over 12 700  cubic metres per second, compared to a seasonal average of 4200 cubic metres per second. Such high flow rates on the Koshi River almost invariably lead to significant flood events in Bihar State, India.

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At least 157 people dead following Magnitude 5.7 Earthquake in Jajarkot District, Nepal.

The United States Geological Survey recorded a Magnitude 5.7 Earthquake at a depth of 16.5 km, in Jajarkot District, Nepal slightly after 11.45 pm local time, (slightly after 6.00 pm GMT) on Friday 3 November 2023. At the time of writing 157 people have been confirmed dead following the event, and 184 injured, with many more made homeless as large numbers of mud-brick buildings collapsed in the region. Such buildings are particularly vulnerable to Earthquakes as the bricks often liquefy, trapping people inside and quickly asphyxiating them with dust. This is particularly dangerous at night when the majority of people are inside sleeping.

Damage caused by an Earthquake in the west of Nepal on 3 November 2023. EPA/EFA/Rex/Shutterstock.

Earthquake activity in Nepal is caused by the uplift of the Tibetan Plateau, due to the impact of India into Eurasia to the south. The Indian Plate is moving northwards at a rate of 5 cm per year, causing it to impact into Eurasia, which is also moving northward, but only at a rate of 2 cm per year. The collision of the Indian and Eurasian plates has led to the formation of the Himalayan Mountains, the Tibetan Plateau, and the mountains of southwest China, Central Asia and the Hindu Kush.

Block diagram showing how the impact of the Indian Plate into Eurasia is causing uplift on the Tibetan Plateau. Jayne Doucette/Woods Hole Oceanographic Institution.

Much of northern India and neighbouring areas of Central Asia and the Himalayas, are prone to Earthquakes, caused by the impact of the Indian Plate into Eurasia from the south. When two tectonic plates collide in this way and one or both are oceanic then one will be subducted beneath the other (if one of the plates is continental then the other will be subducted), but if both plates are continental then subduction will not fully occur, but instead the plates will crumple, leading to folding and uplift (and quite a lot of Earthquakes). The collision of the Indian and Eurasian plates has led to the formation of the Himalayan Mountains, the Tibetan Plateau, and the mountains of southwest China, Central Asia and the Hindu Kush.

The movement of India into Eurasia over the last 71 million years. USGS.

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