The Himalayas may be receiving significantly more snowfall than previously estimated, according to a new study that could reshape scientific understanding of one of Asia’s most important freshwater sources. Researchers have found that widely used snowfall analyses underestimated seasonal snowfall by as much as 37 per cent over the Lake Hampta region in Himachal Pradesh during a single winter, highlighting major gaps in existing measurement methods.
The findings, published in the Monthly Weather Review, suggest that snowfall across the west-central Himalayas has been miscalculated for years. The international research team, comprising scientists from the British Antarctic Survey, the UK Met Office and the Indian Institute of Technology (IIT) Kharagpur, has introduced an innovative technique that promises more accurate estimates of snowfall in some of the world’s most challenging mountain landscapes.
Accurately measuring snowfall in the Himalayas has long been a scientific challenge. Rugged terrain, harsh weather conditions and limited monitoring infrastructure make it difficult for conventional instruments to capture the true amount of snow that falls across high-altitude regions. Yet snowfall is a critical component of the Earth’s water cycle and serves as a vital source of freshwater for millions of people downstream.
To overcome these limitations, the researchers turned to an unlikely ally—high-altitude frozen lakes. Rather than relying solely on traditional weather instruments, the team used commercially available water-pressure sensors installed beneath the surfaces of three lakes: Ghepan and Hampta in the western Himalayas of Himachal Pradesh, and Mugu Lake in Nepal.
According to lead author Siddharth Gumber, a mountain climate scientist with the British Antarctic Survey, the lakes themselves function as vast natural pressure sensors. Unlike conventional instruments that record snowfall at a single point, the lake-based system effectively measures snowfall across the entire frozen surface, which can span thousands to billions of square metres. This allows scientists to capture both the timing and intensity of snowfall with far greater accuracy.
The technology is based on Archimedes’ principle of displacement. As snow accumulates on the frozen lake surface, it increases the pressure exerted on the water beneath the ice. The submerged sensors detect these pressure changes, enabling researchers to directly calculate the mass of accumulating snow. Because the method measures snow mass rather than relying on indirect estimates, it provides a more accurate and unbiased assessment of snowfall.
The study found that the improved model not only reproduced the timing of snowfall events with remarkable accuracy but also closely matched the amount of snow that accumulated throughout the season. It performed particularly well during extreme snowfall events, which are often the most difficult for existing models to represent accurately.
“The results show that the model can accurately simulate both the timing and amounts of the snowfall observations and can effectively be used for the generation of long-term snowfall products,” the researchers wrote.
The implications extend far beyond scientific research. Knowing precisely when and how much snow falls is essential for predicting the timing of snowmelt, estimating river flows and assessing future water availability. These insights could help governments, water managers and local communities prepare more effectively for seasonal water shortages and changing climate conditions.
Gumber noted that mountain water supplies are becoming increasingly uncertain as parts of the Himalayan region begin experiencing more frequent water stress. Despite the mountains serving as the source of many major rivers across South Asia, significant uncertainties remain about exactly how much water they provide and how those supplies may change in a warming climate.
“Good measurements of snowfall are now more important than ever for predicting the future of water resources, which until now have been lacking,” Gumber said.
The study underscores the growing need for more reliable observations in mountain environments. As climate change alters snowfall patterns and accelerates glacier retreat, improved monitoring techniques such as lake-based pressure sensing could play a crucial role in strengthening weather forecasting, water-resource planning and long-term climate research across the Himalayan region. (Agencies)
