KATHMANDU:- Glacier melt in the Hindu Kush Himalaya (HKH) has doubled since 2000, according to two major reports from ICIMOD that were released on Saturday to mark the World Day for Glaciers.

The region has lost up to 27 metres of ice thickness since 1975, putting the water and food security of nearly two billion people at risk.

Experts warn that the “Water Towers of Asia” are reaching a critical tipping point. With 12 per cent of glacier area already gone, officials are calling for urgent global action to prevent a “real-time crisis” of floods and water shortages.

The reports, Changing Dynamics of Glaciers in the Hindu Kush Himalaya Region from 1990 to 2020 and HKH Glacier Outlook 2026: Insights from 50 Years of Himalayan Glacier Monitoring, provided the most comprehensive evidence yet of glacier change in the region, said a press statement issued by ICIMOD to mark the day on March 21.

The reports revealed a total loss of up to 27 metres of ice thickness since 1975, sounding an alarm for the nearly two billion people downstream who depend on meltwater from the ‘Water Towers of Asia’.

According to the statement, HKH holds the largest volume of ice outside the poles, with an inventory of over 63,700 glaciers covering nearly 55,782 square kilometres. These glaciers are the source of at least ten major Asian river systems, supporting the food, water, energy, and livelihood security of billions. However, around 78 per cent of this glacier area, located between 4,500 and 6,000 metres above sea level is highly exposed to elevation-dependent warming.

“This is not a distant problem; it is a crisis unfolding in real-time, with new disasters every summer and monsoon. The fact that ice loss rates have doubled this century should shock us all into action,” said Pema Gyamtsho, Director General of ICIMOD.

He said, “The HKH is at a crossroads. The rapidly escalating impacts we are seeing from water uncertainty to catastrophic floods underscore that we are in a critical decade for the cryosphere. We must scale up monitoring and invest in adaptation now. These aren’t blind spots becoming surprises anymore; they are our new reality.”

The analysis revealed that between 1990 and 2020, HKH glaciers lost about 12 per cent of their total area and nine per cent of their estimated ice reserves.

According to Sudan Bikash Maharjan, Remote Sensing Analyst at ICIMOD and lead author of the glacier dynamics report, the most immediate threat comes from the region’s smallest glaciers.

“Between 1990 and 2020, HKH glaciers lost about 12 per cent of their total area, but the losses are most acute for the region’s smallest glaciers — those below 0.5 km² — which are shrinking more rapidly than others,” said Maharjan.

“This poses immediate risks of localised water shortages for high mountain communities and intensifies hazards like glacial lake outburst floods.

The danger is magnified because three-quarters of the region’s glaciers fall into this vulnerable size class. We are not just losing ice; we are facing a rapid escalation of risks,” he said.

The HKH Glacier Outlook 2026 synthesises data from 38 monitored glaciers, revealing that widespread wastage has doubled post-2000, signalling that parts of the Himalayan cryosphere may be nearing critical tipping points toward irreversible retreat.

Yet, the reports highlighted a critical data gap — of those 38, only seven meet the global benchmark monitoring standards of the World Glacier Monitoring Service (WGMS). Major glacierised regions including the Karakoram, Sikkim, Zanskar, and Bhutan remain largely unmonitored.

“We are trying to navigate a rapidly changing future with an incomplete map,” said Mohd. Farooq Aslam, a cryosphere specialist at ICIMOD and one of the report’s authors.

“Large parts of the Himalaya remain blind spots. Without expanding our monitoring networks and standardising methodologies, accelerated changes in water flows and cryosphere risks could remain undetected until the impacts are severe. Sustained monitoring of representative glaciers like Mera and Rikha Samba in Nepal, and Chhota Shigri in India, is critical, they are our early warning indicators for the entire mountain system.”

The reports also highlighted that glacier losses are spatially skewed, with the highest percentage of area loss in the eastern Hengduan Shan Mountains, where some areas lost up to 33 per cent of their glacier area in just three decades. However, the largest absolute area losses are concentrated in the Indus, Ganges and Brahmaputra basins, where over 74 per cent of the region’s glaciers are found, underlining their critical vulnerability.

The larger glaciers above 10 km² hold nearly 40 per cent of the region’s natural water reserves. The heavily glaciated Karakoram range, home to 18 of the 25 largest glaciers, remains highly vulnerable to long-term water, food, and disaster risks with ramifications for the entire region.

With 2025 designated as the International Year of Glaciers’ Preservation and the start of the Decade of Action for Cryospheric Sciences (2025 to 2034), these findings serve as a stark reminder of the urgent need for action.