Baspa River Hydrology
A new scientific study has found that glaciers in Himachal Pradesh’s Baspa River basin are melting much faster than earlier thought. The research, carried out by scientists from the Indian Institute of Science (IISc), Bengaluru, and the Manipal Institute of Technology, shows that the rate of ice loss in the region is more than double previous estimates.
The study, published in the Journal of Earth System Science (2025), used a new and improved technique to measure glacier melt. The researchers developed a Modified Improved Accumulation Area Ratio (IAAR) method, which calculates melting for each glacier separately instead of using one common value for the whole basin. This small change made a big difference, reducing calculation errors by nearly 20% and giving a clearer picture of how fast the glaciers are actually shrinking.
Rate of Declining Glaciers
Using this new approach, scientists found that 33 glaciers in the Baspa basin are losing about 0.11 gigatonnes of ice every year, compared to older estimates of just 0.03 gigatonnes. Over the study period from 1985 to 2013, the total ice loss comes to about 2.7 gigatonnes — roughly equivalent to more than a million Olympic-sized swimming pools of water.(see Map of Important Glaciers of Himachal Pradesh)
Warming Rate
Researchers also discovered that the upper Himalayas are warming faster than lower areas — by nearly 0.5°C every decade above 4,000 meters — speeding up glacier melt.
Dr. Harini Santhanam, one of the lead authors, explained, “Our refined model gives a more accurate picture of how glaciers are responding to climate change. This information is vital because these glaciers are lifelines for rivers, farms, and hydro projects downstream.”
Baspa River
The Baspa River, a tributary of the Satluj, supports local farming and several hydropower projects. Faster melting may cause more water flow in the short term but could lead to serious shortages later as glaciers continue to shrink. The researchers warn that it could also increase the risk of glacial lake outburst floods (GLOFs) — sudden and dangerous floods caused when glacier lakes burst.(seeSatluj River ,Himachal Pradesh, a Holistic Study.)
The study was supported by the Indian Space Research Organisation (ISRO) under its Cryosphere Application Programme. Scientists say similar studies should be carried out in other Himalayan basins to help predict water availability and plan for the future.
This research adds to growing evidence that Himalayan glaciers are melting at alarming rates, and experts say the time for action is now — through better monitoring, conservation efforts, and climate-aware water management policies.
