top of page
Search

Himalayan Ice in Accelerated Retreat: When Asia’s “Water Tower” Loses Its Winter

“Mountains that used to be white in winter are increasingly turning grey.”


This impression is not anecdotal but reflects a trend that satellite observations now confirm with growing clarity: across the high mountains of the Hindu Kush and the Himalayas, winter snow cover is shrinking, while glaciers are losing mass at an accelerating pace.


This is no longer merely a question of landscape aesthetics, but a question of water timing—when water arrives, how much of it there is, and how reliable it remains.


Colorful prayer flags flutter near an ornate arch in a snowy mountain landscape under a bright blue sky.

For centuries, the Himalayas functioned as a natural reservoir.

Snow stored water over winter and released it gradually into rivers during spring and summer, while glaciers provided a steady baseflow during dry periods.


Today, two changes are unfolding simultaneously—and their combined effect is destabilising water systems from the Indus to the Mekong.


1) “Snow droughts”: when there is less snow—or when it disappears too quickly


The most relevant recent data come from ICIMOD.

Its HKH Snow Update 2025 reports that snow persistence in the 2024/25 season was the lowest in 23 years, standing 23.6% below the long-term average.


The same assessment highlights that this trend poses a risk to the water security of nearly two billion people who depend directly or indirectly on snow- and glacier-fed rivers across Asia’s major basins.

A key point for readers is that snow persistence does not simply mean “how much snow falls,” but how long snow remains on the ground. In a warmer atmosphere, snowfall may still occur, but higher average temperatures and heatwaves can melt it rapidly. As a result, a “snow drought” can emerge even in winters with individual snowfall events—because the snow no longer provides the long seasonal tail that once sustained rivers well into late spring and summer.


This shift is often linked to changes in winter weather systems—such as weaker and more erratic cold-season disturbances bringing precipitation to high elevations—combined with rising temperatures. The outcome is less snow, more rain, and faster melting.


2) Glaciers: global trends are increasingly measurable—and alarming


If snow is the short-term regulator of the hydrological year, glaciers are its long-term reserve. Here, the picture is even more stark.


Large synthesis studies in recent years show that mass loss from mountain glaciers is accelerating, with exceptionally poor years in the recent past—frequently cited in media coverage, with 2023 standing out as one of the worst on record.


Why does this matter for the Himalayas?

Because glacier change is rarely a smooth, linear process of “a little less each year.” Instead, it represents a regime shift:


  • melting begins earlier in the year,

  • melt rates intensify during certain periods,

  • and after an initial phase of increased runoff, glacier reserves shrink to the point where dry-season flows begin to decline precisely when demand is highest.


One of the most consequential findings from scientific publications in 2025 is the scale of difference between warming pathways. Research synthesised across academic and research institutions shows that limiting warming to around 1.5°C could preserve roughly twice as much glacier mass as a trajectory leading toward ~2.7°C. The message is simple: every tenth of a degree matters.


Another powerful framing comes from Nature Climate Change: the concept of “peak glacier extinction.” It describes a period—expected around the middle of the 21st century—when the number of glaciers disappearing each year will reach a maximum, followed by a longer phase of continued but numerically slower loss, leaving behind a permanently altered “glacier geography” of the planet.This concept resonates because it translates abstract mass loss into something tangible: glaciers as individual entities will vanish, not merely thin.


3) Hydrology: more dangerous extremes and a less reliable “summer reserve”


When snow melts earlier, river inflows shift toward spring. This has three consequences that are easy to grasp:


  • more water earlier, less later (a timing shift of the natural reservoir),

  • greater dependence on an increasingly unpredictable monsoon,

  • higher risk of simultaneous floods and droughts, as natural buffering capacity erodes.


In practical terms, the gap widens between when water is available and when people need it most—for pre-monsoon agriculture, dry-season hydropower generation, and urban water supply during heatwaves.

At the same time, infrastructure such as dams, irrigation networks, and flood-control systems becomes more exposed to volatility: larger volumes of water over shorter periods and declining predictability.


For a concise “big-picture” reference, UNESCO’s State of the Cryosphere 2024 – Lost Ice, Global Damage warns that cryosphere loss significantly increases social and economic costs and that risks escalate sharply under higher warming scenarios—even as societies must prepare for impacts under more ambitious mitigation pathways.


4) GLOFs: when melting creates new “lake bombs”


A critical contemporary tension point—and a visually powerful one—is the rapid expansion of glacial lakes and the associated risk of sudden floods known as GLOFs (glacial lake outburst floods).


Reporting by Down To Earth, based on a study published in January 2026, notes that since 1990:


  • the number of glacial lakes has increased by 53%,

  • their total area by 51%,

  • and their volume by 48%—while risk assessments and early-warning systems lag behind the pace of change.


This is not merely another side-effect of glacier retreat, but a transformation of the Himalayas’ risk profile. More lakes mean more potential points of failure in natural dams of ice or moraine, which—when triggered by intense rainfall, landslides, or heat surges—can unleash devastating flood waves through narrow mountain valleys.


Here, a double paradox becomes evident:


  • in the short term, melting can mean more water,

  • at the same time, it brings greater hazards (lakes, landslides, unstable slopes),

  • and in the long run, it results in less water as glacier reserves decline.


Why melting Himalayan ice should concern Slovenia and Europe


At first glance, the Himalayas may seem distant—geographically, politically, and culturally. Yet in an era of interconnected climate, economic, and security systems, the loss of Himalayan ice is very much a European issue.


First, the Himalayas act as a global regulator of climate and water systems: changes in snow and ice dynamics influence the Asian monsoon, which in turn affects large-scale atmospheric circulation patterns linked to weather variability in Europe.


Second, water instability across South and Southeast Asia directly affects global food security, energy markets, and commodity prices, impacts that Europe experiences through trade, geopolitical tensions, and economic volatility.


Third, the Himalayas are a mirror of the future of the European Alps: processes unfolding today in the “Third Pole” are already visible—albeit in milder form—in Alpine regions, from shortening snow seasons and glacier retreat to more frequent hydrological extremes.


For Slovenia—an Alpine country with abundant water resources and strong reliance on stable hydrological regimes—the message is clear: melting ice in the Himalayas is not a distant crisis, but an early warning of how rapidly the balance underpinning water availability, energy systems, agriculture, and long-term security in Europe can be disrupted.


What is new—and why it matters now


  • ICIMOD (April 2025): the 2024/25 season marks a 23-year record low in snow persistence, −23.6% below normal.

  • January 2026: reporting on the rapid expansion of glacial lakes (+53% in number; +51% in area; +48% in volume since 1990) and major gaps in GLOF risk assessment.

  • 2025 research syntheses: under ~1.5°C warming, roughly twice as much glacier mass can be preserved compared to a ~2.7°C pathway.

  • 2025: the concept of “peak glacier extinction”, highlighting a mid-century peak in the disappearance of glaciers as individual entities.


Conclusion: two levels of response—and both are essential


First, without rapid global emissions reductions, Asia’s “water tower” will lose its winter faster than societies can adapt. The difference between 1.5°C and higher warming scenarios is not academic—it defines fundamentally different glacier futures and water-security outcomes.


Second, adaptation is no longer optional. It requires improved monitoring of snow and ice, cross-border data sharing, early-warning systems (including for GLOFs), smarter water storage, more efficient agricultural use, and coordinated transboundary river-basin governance. Rivers do not respect political borders—and neither does the cryosphere.


Sources and further reading


©2025 by Eva Premk Bogataj - All Rights Reserved

​

bottom of page