By Salam Rajesh
Nepal’s recent disastrous Himalayan crisis on 26 August was a ‘catastrophic event with almost no warning’, say climate observers. The crisis highlights a growing challenge for the Himalayas wherein mountain hazards are becoming increasingly complex.
Scientists analyzing satellite imagery, seismic signals, video footage, numerical models and regional climate data have concluded that the event was most likely triggered by an ice-rock avalanche, rather than a glacial lake outburst flood (GLOF).
According to reports, the available assessment indicates that the direct impact of the ice-rock avalanche and the resulting debris flow primarily caused the catastrophic flooding.
Dr Farooq Azam, Senior Cryosphere Specialist and Intervention Manager at ICIMOD says, “This was an unprecedented and unexpected disaster. There was simply no detection and no time to issue a warning. The event was a sudden-onset hazard that could not be captured by conventional warning systems. However, if there had been an early warning system, it could have saved lives to some extent”.
Aarti Khosla, Director, Climate Trends, adds in: “This was not a distant disaster – the Hindu Kush Himalayan range stretches across India and neighboring countries. It was also a disaster which was predicted by climate models many years ago. Nepal is paying the price for a crisis it did not create”.
The immediate priorities are stronger land-use planning, resilient infrastructure and greater community awareness of high-altitude hazards, and governments need to reconsider how infrastructure is planned in the Himalayas, Dr Farooq stressed.
ICIMOD’s recent report, ‘HKH Glacier Outlook 2026’, notes that the glaciers in the Hindu Kush Himalaya (HKH) region are rapidly shrinking due to climate change, with mass loss accelerating significantly since 2000. Over 50 years of observations show that about 89% of recorded years had negative glacier mass balance, indicating consistent decline, the report noted.
The report points out that the Himalayan region, geologically the youngest and extremely fragile, has experienced significant warming in the 21st century, with rates ranging from 0.15 degrees Celsius to 0.60 degrees Celsius per decade, far exceeding the global average of 0.74 degrees Celsius per century.
This glacier loss is affecting water availability, increasing glacial lake outburst flood (GLOF) risks, and threatening the livelihoods of nearly two billion people dependent on these water systems across India, Nepal, Bhutan, Bangladesh, Pakistan, Afghanistan, China and Myanmar.
Anjal Prakash, Professor, Public Policy, FLAME University and IPCC Author, is rather critical when he says, “Nepal’s mountains have been sending warnings for a decade: thinning glaciers, retreating snowlines, permafrost turning to slush under roads and hydropower plants we kept building. We did not lack the science, we lacked the political will to act on it”.
The event showed the challenges faced by risk management system in the Himalayan region, which is increasingly becoming extremely vulnerable. Unlike hazards that can be monitored through rising water levels or known glacial lakes, ice-rock avalanches can originate from unstable slopes, glaciers or areas below the visible surface. Detecting where and when such failures may occur, remains extremely difficult, the ICIMOD report stressed.
The report sets three immediate priorities in preparing for increasing mountain hazards.
Firstly, strengthen and enforce land-use planning, and develop a clear land-use policy for the Hindu Kush Himalaya (HKH), ensuring strict implementation, particularly in areas exposed to river, slope and mountain hazards.
Secondly, assess how the environment can impact infrastructure. Early warning systems can help save lives, but they cannot necessarily protect infrastructure from sudden events. Alongside conventional Environmental Impact Assessments (EIAs) before infrastructure is built, governments should assess how changing environmental conditions could affect infrastructure over its lifetime.
Thirdly, include indigenous knowledge into risk planning. Revisit traditional settlement and indigenous land-use practices. Historically, communities often lived on higher ground and away from river channels, while newer development has increasingly moved closer to riverbanks and, in some cases, onto riverbeds.
The Nepal disaster is a potential recipe for neighboring country Bhutan, another of the Himalayan nation state perched precariously amongst fragile mountain landscape that is fast deteriorating from climate change impacts, in particular receding glaciers and increasingly evident glacial lake formation.
Over the past decades, scientific monitoring has revealed a clear and accelerating transformation of HKH glaciers. Many glaciers are losing mass at increasing rates, altering runoff patterns and contributing to the expansion of glacial lakes, with implications for Glacial Lake Outburst Flood (GLOF) risk and long-term water supply stability.
These changes are already influencing seasonal water availability, hydropower reliability, and mountain livelihoods, underscoring the urgency of coordinated monitoring and policy action among regional member countries, notes ICIMOD’s 2026 report.
Strengthening glacier monitoring across the Hindu Kush Himalaya (HKH) requires coordinated regional action focused on expanding observation networks into underrepresented regions, such as the Karakoram, Sikkim, Zanskar, and the Bhutanese Himalaya.
At the same time, it is essential to sustain long-term monitoring of benchmark and representative glaciers and to standardize monitoring methodologies to improve the comparability of datasets across the region, the report emphasized.
A 12-member team representing the Media Resource Centre of the Directorate of Environment & Climate Change, Government of Manipur, on a recent visit to the Himalayan kingdom of Bhutan during August this year was observant to the pervasive concern of climate change implications in the immediate and long term context.
For instance, the team learnt that 36.5 percent of springshed in the Himalayan kingdom had declined in recent times specifically due to climate change implication. This could account with retreating glaciers as most river systems are fed by glaciers.
The other concern resounds with the Nepal disaster. Years back, the BBC had reported the formation of several glacial lakes in the eastern parts of Bhutan resulting from glacial melts. The smaller glacial lakes could subsequently merge as one into a larger lake and result in a massive outburst as disastrous as the 26 August Nepal flashflood, destroying homes and lives within seconds and without warning.
