NEW DELHI: A new study has found that existing methods significantly underestimated snowfall in parts of the Himalayas, with previous analyses recording 37 per cent less seasonal snowfall over the Lake Hampta area in Himachal Pradesh during a single winter.
The study, conducted by researchers from the British Antarctic Survey, the UK Met Office and the Indian Institute of Technology (IIT) Kharagpur, provides improved estimates of snowfall across the western-central Himalayas and highlights the need for more accurate monitoring of mountain water resources.
Published in the journal Monthly Weather Review, the research notes that measuring snowfall in mountainous terrain has long been a challenge due to complex topography and harsh weather conditions.
To overcome these challenges, researchers used high-altitude frozen lakes as natural pressure sensors to monitor snowfall. Commercially available water-pressure sensors were installed at Ghepan and Hampta lakes in the western Himalayas and Mugu Lake in Nepal.
The sensors measure changes in water pressure caused by the weight of accumulating snow, enabling scientists to directly estimate snowfall using the principle of displacement. Unlike conventional instruments, the system monitors the entire lake surface, providing more accurate measurements of snowfall timing and intensity.
The study found that the improved model accurately reproduced both the timing and volume of snowfall, particularly during extreme snowfall events, making it suitable for generating long-term snowfall records.
Researchers said accurate snowfall data is critical for predicting snowmelt and river flows, which are essential for managing freshwater resources and preparing for water shortages in the Himalayan region.
The study also cautioned that climate change is increasing uncertainty over future mountain water supplies, making reliable snowfall measurements more important than ever for water resource planning and policymaking.
