By Muhammad Zulqarnain

A deadly ice-rock avalanche that unleashed catastrophic flooding along the Nepal-China border has highlighted growing concerns over increasingly complex hazards across the rapidly warming Himalayan region, with experts calling for stronger cross-border monitoring and early-warning systems.

The August 26 disaster apparently began when glacier ice and bedrock collapsed from a steep slope in the upper Bhote Koshi watershed. The avalanche carried ice, rock and sediment into the Lhende River, generating a debris flow and temporarily blocking the channel.

The blockage was a natural barrier formed by debris. Its subsequent overtopping or failure sent a powerful flood surge through Nepal's Rasuwa district and adjoining areas of China's Xizang Autonomous Region.

The disaster, however, occurred against the backdrop of rapid changes across the Himalayan cryosphere.

According to ICIMOD, the region is warming at roughly twice the global average and lost about 12% of its glacier area and 9% of its estimated ice reserves between 1990 and 2020, while glacier wastage has approximately doubled since 2000.

Rising temperatures can accelerate glacier retreat, thaw permafrost, destabilise ice and rock slopes and expand glacial lakes, creating conditions for multiple interconnected hazards.

Such events can develop into cascading disasters in which a slope collapse triggers an avalanche, debris flow, river blockage and flash flood, threatening settlements, roads, bridges, hydropower infrastructure and farmland across mountain regions.

Speaking to Wealth Pakistan, Aisha Khan, Chief Executive of the Civil Society Coalition for Climate Change and the Mountain and Glacier Protection Organization, said the Nepal-China border disaster should be regarded as a regional warning.

“The glacier-triggered flood is not a freak disaster. It is a warning that climate change is turning the region's water tower into a source of systemic economic and security risk,” she said.

Khan said glacier melting could initially increase river runoff, expand glacial lakes and intensify flood risks. Continued glacier retreat could eventually reduce meltwater availability, exposing the region to water scarcity after a period of heightened flooding.

She said cryospheric disasters, with their transboundary implications, are highly dynamic and difficult to predict. Governments across borders need geomorphological studies and hydrometeorological data from interconnected mountain systems and valleys to develop credible risk scenarios.

The combined effects of temperature spikes, changing permafrost conditions and glacier response could not always be anticipated, she said. However, a coordinated early-warning mechanism across the Hindu Kush Himalaya could help reduce risks and protect vulnerable communities.

Khan proposed a “Third Pole Risk Compact” linking glacier and glacial-lake monitoring, satellite observations, hydrological forecasting, early-warning systems and disaster-management authorities across the region.

Ijlal Haider, a climate activist and researcher from Gilgit-Baltistan, said rising risks across the Himalayas require early-warning systems combining modern monitoring technology with the indigenous knowledge of mountain communities.

He said local shepherds, drawing on generations of experience, could detect changes in clouds and animal and insect behaviour that might signal an approaching hazard.

Integrating these observations into formal warning systems and involving communities in their operation could strengthen preparedness against increasingly complex Himalayan disasters, he told Wealth Pakistan.

Rizwan A. Malik, Director for Climate Finance, ESG and Sustainability, said greater resources should be directed towards prevention in disaster-prone regions, as monitoring equipment and early-warning systems cost considerably less than post-disaster reconstruction.

He said cross-border coordination is essential because glacier collapses, river blockages and glacial lake outburst floods could originate in one country and rapidly threaten people and infrastructure in another.

Malik said greater investment in monitoring, forecasting and coordinated warning systems could help Himalayan countries identify emerging hazards earlier and reduce their human and economic consequences.

Credit: INP-WealthPk