The Hindu Kush Himalaya (HKH), often referred to as Asia’s water tower, has once again recorded an alarming climatic anomaly. The latest Snow Update Report 2025 from ICIMOD reveals a stark 23-year low in snow persistence — the fraction of time snow remains on the ground — marking the third consecutive year of below-normal snowfall across the region.

This development signals serious water security implications for nearly two billion people dependent on the region’s 12 major river basins.

A Comparative Breakdown: Where Snow Is Vanishing Fastest:

The 2025 data shows the most drastic declines in snow persistence in the Mekong (-51.9%) and Salween (-48.3%) basins — both historically volatile but now dangerously unstable. The Tibetan Plateau, considered the climate bellwether of Asia, dropped from a 2022 high of +92.4% to -29.1% in 2025. These fluctuations underscore a rapidly destabilizing regional climate.

River basins such as the Brahmaputra (-27.9%), Yangtze (-26.3%), and Ganges (-24.1%) have also shown marked deterioration, with ripple effects anticipated in agriculture and hydropower sectors. The Ganges Basin, for instance, which enjoyed peak snow persistence of +30.2% in 2015, now faces a historic low, putting at risk early summer river flows and monsoon synchrony.

The Indus Basin, lifeline to nearly 300 million people in Pakistan and northwestern India, posted a -16% anomaly. Although marginally better than the 2024 record low of -24.5%, it remains in the red zone. Snowmelt contributes heavily to the Indus, and persistent shortfalls may intensify both urban and rural water stress across Punjab and Sindh.

Temporal Comparisons: Trends Worsening Over Years:

This year’s data fits into a deeply concerning long-term trend. From 2003 to 2025, snow persistence has been declining across the board, with more extreme variability since 2019. For instance, the Mekong Basin plunged from a high of +80.3% in 2019 to its lowest-ever level this year. Likewise, the Amu Darya Basin dropped from +40.4% in 2008 to -18.8% this year, the fourth lowest in 23 years.

Even basins like Tarim and Helmand, which showed moderate deficits in 2025, are far from stable. Tarim saw its sixth straight year of negative snow persistence, while Helmand’s continuing moderate decline still aggravates Afghanistan’s socio-environmental vulnerabilities.

Eastern vs. Western Divide: Differing Degrees, Shared Crisis:

Interestingly, the report notes some regional variation. The western basins, including Indus and Amu Darya, have fared marginally better this year compared to 2024, yet remain below normal. In contrast, eastern basins such as Mekong and Salween, which had better snow years previously, have now recorded some of the steepest declines.

According to Dr. Sher Muhammad, lead author of the report, “This east-west divergence in snow persistence highlights the region’s complex hydroclimatic dynamics. While western basins rely heavily on snowmelt, eastern basins face increasing irregularity — a pattern that calls for region-specific adaptation strategies.

 ICIMOD’s Director General Pema Gyamtsho didn’t mince words, stating that the region is now “locked into an irreversible course of recurrent snow anomalies.” He called for a paradigm shift in water and climate governance, urging governments to “embrace science-based, forward-looking policies” and strengthen transboundary water cooperation.

Recommendations & Call to Action
Basin-specific adaptive water resource management

1. Investment in seasonal water storage infrastructure
2. Integration of snow anomaly data into national water strategies
3. Stronger cross-sectoral coordination and decision-making
4. With rising heatwaves and erratic precipitation already burdening millions, delayed action could amplify socio-political tensions over shared water resources, especially in regions like South Asia, where climate vulnerability intersects with fragile governance.

The 2025 snow data is more than just numbers—it’s a stark warning. Climate-induced snow anomalies in the HKH are no longer future projections; they are unfolding realities. If trends continue unchecked, water stress, food insecurity, and energy shortages could become the new normal across Asia.