KATHMANDU: The Hindu Kush Himalaya (HKH) region has entered its third straight year of below-normal snowfall, with snow persistence plummeting to a 23-year record low of –23.6%, according to the 2025 Snow Update Report. The report raises serious concerns for the water security of nearly two billion people across 12 major river basins originating in the HKH.
ICIMOD Director General Pema Gyamtsho launched the report, urging governments to act urgently. “Carbon emissions have locked us into recurring snow anomalies in the HKH,” he said. “We must shift to science-driven, forward-looking policies and strengthen regional cooperation on water management and emissions mitigation.”
Snowmelt accounts for about 25% of annual river runoff in the region, with western basins relying even more heavily on it. This continuing deficit in seasonal snowmelt is reducing river flows and triggering early-summer water stress for downstream communities, already hit by worsening heatwaves.
ICIMOD Remote Sensing Specialist Sher Muhammad, who led the report, warned: “We are seeing these deficits year after year—an alarming trend. While our report gives a regional picture, each country must assess the specific snowmelt dependency of its basins and act accordingly.”
Key findings by basin include
Mekong: Snow persistence dropped by -51.9%, the lowest in 23 years.
Salween: Recorded a -48.3% drop, down sharply from a 2020 high.
Tibetan Plateau: Fell by -29.1%, highlighting extreme climate sensitivity.
Brahmaputra: Declined steadily to -27.9% from a 2019 high.
Yangtze: Reported -26.3%, the sixth-lowest in 23 years.
Ganges: Hit a record low of -24.1%, down from its 2015 peak.
Indus: Dropped to -16%, threatening water supply for 300 million people.
Yellow River: Despite minor recovery to -18.6%, remains in long-term deficit.
Amu Darya & Helmand: Continued to show moderate to serious declines.
The report urges governments to take basin-level adaptive action to address shrinking snow resources. It recommends investing in seasonal storage systems, improving meltwater efficiency, preparing national drought plans, and integrating snow anomaly data into water, agriculture, and energy strategies.
Experts emphasize that while the west continues to face persistent snow deficits, eastern basins that previously held steady—like the Mekong and Salween—are now experiencing sharp declines, showing that no basin is immune to the impacts of climate change.
