The images coming out of Nepal are difficult to comprehend. A glacial collapse in the Langtang region, followed by a devastating flash flood through the Bhote Koshi-Trishuli river system, has once again reminded us that the Himalayas are not merely magnificent mountains. They are living, moving, increasingly unstable ecosystems — and millions of lives downstream depend on their stability.
The August 26 disaster is still unfolding. Nepal’s authorities are continuing search and rescue operations, and casualty figures are changing rapidly. By August 31, international reports were putting the combined death toll at more than 900, with thousands still missing. Hundreds of workers were reportedly trapped in hydropower tunnels. Nepal’s own Ministry of Home Affairs says the full human and material damage is still being assessed, and that long-term rehabilitation of survivors will be as critical as immediate rescue.
But there is a question that we must ask beyond the immediate tragedy: Where will the survivors go when the mountains around them become increasingly difficult to inhabit? And another, perhaps even more uncomfortable one: Could Nepal become South Asia’s next major climate-migration hotspot — perhaps the “new Bangladesh” of climate mobility?
The comparison is deliberately provocative. Nepal and Bangladesh face very different climate risks. Bangladesh’s vulnerability is overwhelmingly associated with its low-lying delta, sea-level rise, cyclones, river flooding, salinity intrusion and erosion. Nepal’s emerging crisis is different. It begins much higher up — in the glaciers, mountains, slopes and headwaters — and then travels downstream through rivers, agriculture, infrastructure and eventually human mobility.
In Bangladesh, the question is increasingly about how people living downstream can survive a rising and shifting sea and increasingly volatile rivers. In Nepal, the question is becoming how people living upstream can survive a rapidly destabilising mountain system. And these two stories are actually connected.
It would be a mistake to describe the latest Nepal catastrophe simply as another “natural disaster.” Scientists are still examining the precise chain of events behind the August 26 collapse. Initial assessments indicate that a large mass of ice and rock collapsed at high altitude, potentially creating a temporary blockage before unleashing a massive debris-laden flood. The Trishuli river reportedly rose by as much as nine metres within around 30 minutes. Scientists have also pointed to warming, glacier retreat and weakening high-altitude permafrost as factors increasing instability, while cautioning that no individual event can be attributed solely to climate change. That distinction is important. Climate change does not need to “cause” every disaster to make disasters more dangerous. It changes the conditions under which disasters occur.
The Himalayas are warming. Glaciers are retreating. Permafrost is weakening. Glacial lakes are expanding. Snow patterns are changing. Rain is increasingly replacing snow at higher elevations. And an infrastructure boom is placing roads, hydropower projects, settlements and economic assets in valleys where the consequences of a mountain failure can be catastrophic.
An assessment by ICIMOD finds out that between 1990 and 2020, glaciers across the Hindu Kush Himalaya lost around 12 percent of their area and 9 percent of their estimated ice reserves. Glacier ice loss has accelerated dramatically since 2000. ICIMOD’s 2026 assessment says ice-loss rates have effectively doubled since the beginning of this century, with up to 27 metres of ice thickness lost since 1975 in parts of the region. The earlier ICIMOD assessment warned that even if warming is limited to 1.5°C, the Hindu Kush Himalaya could still lose around 30 per cent of its glacier volume by 2100. Under much higher-emission pathways, losses could reach 70-80 per cent.
So, the popular statement that “80 per cent of Himalayan glaciers could disappear” needs some qualification: it refers to high-emission scenarios and glacier volume, not an immediate prediction that 80 per cent of all Himalayan glaciers will simply vanish. But the underlying warning is no less alarming. Even at 1.5°C, the Himalayas are already committed to substantial cryospheric loss. And that means more than melting ice. It means changing water availability, changing agriculture, changing landscapes and changing where people can safely live.
Nepal does not need to wait for a future climate-migration crisis. Migration is already deeply embedded in its social and economic system. According to Nepal’s 2021 census, the country’s absentee rate increased from 3.3 per cent in 2001 to 7.5 per cent in 2021. Around 2.2 million Nepalis were living abroad according to census-based estimates, overwhelmingly of working age and predominantly male. And migration is economically critical. Remittances accounted for roughly 26 per cent of Nepal’s GDP in 2024.
This tells us something important. Nepal already has a vast migration infrastructure — families, networks, recruitment channels, skills, remittance systems and social acceptance of mobility. Climate stress can therefore interact with an already established migration system. When crops fail, water sources disappear, roads are destroyed, tourism declines, livestock productivity falls or an entire settlement becomes unsafe, the decision may not be “migrate or don't migrate.” It may become: Who migrates first? Who stays behind? Who can afford to leave? Where do they go? And under what rights and conditions? This is where climate migration becomes a question of justice.
The link between water, agriculture and migration is not theoretical. FAO’s recent work in Nepal documents how water scarcity, unpredictable weather, declining snowfall, pests and changing agricultural conditions are already contributing to seasonal migration. In Jumla, for example, families have depended on seasonal migration to India because farming alone can no longer reliably support household needs. Climate-resilient agriculture and better water management have begun reducing the pressure to migrate in some communities.
Nepal’s agriculture employs roughly two-thirds of the population and contributes more than a quarter of GDP. Yet rising temperatures, erratic monsoons, drought and extreme events are increasingly disrupting smallholder farming. The problem is not simply too much water. It is also too little water at the wrong time. Nepal’s 2025 paddy production was estimated to be about 4.2 per cent lower than the previous year because rainfall deficits in June and July disrupted planting in important rice-growing areas. FAO’s August 2026 assessment says prospects for the 2026 paddy crop remain uncertain, with below-average rainfall possible in parts of the country. So, the climate-migration equation is becoming increasingly clear. Loss of glacier, erratic rainfall, water stress, crop failure, disaster, weak livelihood alternatives: all of these add to great pressure for distressed out-migration. This pressure does not necessarily begin with a family packing everything into a truck. It can begin with one man leaving for India for six months. Then another family follows and the process continues. We have seen how this process of slow yet forced displacement makes women, who are left to fend from themselves in mountains where springs have died and farms have collapsed, more vulnerable. Many villages could, in a medium term, turn “ghost villages.”
Bangladesh is often held up as the world’s archetypal climate-migration hotspot. And rightly so. The World Bank estimates that climate change could push 13.3 million people into internal migration in Bangladesh over the next 30 years, driven by impacts on agriculture, water availability and rising sea levels. Tropical cyclones alone cost the country roughly US$1 billion annually on average. By 2050, climate variability and extreme events could reduce agricultural GDP by about one-third. But Bangladesh’s climate-migration geography is fundamentally different. Bangladesh is largely dealing with the downstream consequences of a changing water and coastal system. Nepal is sitting at the upstream source of some of South Asia’s most important rivers.
Nepal’s crisis is a South Asia regional crisis too, and it’s going to grow monumentally. What happens to the Himalayas does not stop at Nepal’s borders. The Hindu Kush Himalaya supports water systems upon which roughly two billion people depend. Therefore, asking whether Nepal will “overtake Bangladesh” as a climate-migration hotspot may actually be the wrong question. The more important question is: Will South Asia allow Nepal’s mountain crisis and Bangladesh’s delta crisis to become two separate migration crises when they are part of the same climate system?
The World Bank’s Groundswell analysis projects that climate change could drive up to 40 million internal climate migrants in South Asia by 2050 under a pessimistic scenario, while early action on emissions and resilient development could reduce the scale substantially. Globally, the World Bank estimates that 216 million people could become internal climate migrants by 2050 across six regions, but concerted action could reduce this by as much as 80 per cent. This is where I believe South Asia needs to think beyond individual countries. We urgently need a South Asian Regional Framework on Climate Mobility.
It could be developed through BIMSTEC, SAARC where politically feasible, or through a new coalition of willing South Asian countries. There are already building blocks. At the 2025 Global Platform for Disaster Risk Reduction, Nepal’s Home Secretary Gokarna Mani Duwadee called for a cohesive BIMSTEC disaster mechanism, including synchronised risk assessments, monitoring of Sendai Framework implementation and a dedicated regional disaster-risk-reduction fund.
BIMSTEC, as reports suggest, has also moved beyond declarations. In July 2025, its fourth Disaster Management Exercise brought member states together to test regional preparedness for cyclones and floods. And the 2025 BIMSTEC ministerial process supported the early establishment of a Centre of Excellence in Disaster Management in India.
These are useful foundations. But we need to go much further. Civil society also should play a major role in this. I am sure policy makers, academia, CSOs, UN agencies and other technical institutions — both regional and global — would come together and work towards this.
Views expressed are the author’s own and don’t necessarily reflect those of Down To Earth