Leh: A recent study led by scientists from the Ladakh Regional Centre of the G.B. Pant National Institute of Himalayan Environment, Leh in collaboration with Wadia Institute of Himalayan Geology, IIT-Indore and IISc-Bengaluru has revealed striking differences in glacier melting patterns within Ladakh.
Based on field measurements conducted during 2023–2024, the research highlights how two glaciers—Pensilungpa in western Ladakh and Rulung in eastern Ladakh—are responding very differently to similar climatic conditions. The findings underscore that glacier behaviour is far more complex than previously understood, shaped not just by temperature rise but also by altitude, snowfall, and local geography.
The study reports that the Pensilungpa glacier is experiencing significantly higher melt rates compared to the Rulung glacier. The ablation area-wide mass balance—a key indicator of glacier health—was recorded at -1.08 ± 0.28 metres water equivalent per year for Pensilungpa, nearly 53.5% higher than Rulung’s -0.70 ± 0.18. This suggests a much faster loss of ice in the western part of Ladakh.
Interestingly, Pensilungpa, despite having a substantial debris cover—which typically slows melting—still showed intense ice loss. Scientists attribute this to its lower elevation, extending down to around 4,649 metres above sea level, where temperatures are relatively higher. In contrast, the Rulung glacier lies entirely above 5,600 metres, where colder conditions limit melt.
The study also observed differences in how melting occurs across the glacier surfaces. Pensilungpa displayed irregular and non-linear melt patterns, partly influenced by debris cover. Meanwhile, Rulung exhibited a more uniform and predictable decline in ice thickness, suggesting a more stable but still shrinking system.
Another critical factor identified is snowfall. Data from nearby weather stations showed that western Ladakh receives significantly more snow than the eastern region. However, even higher snow input at Pensilungpa was insufficient to offset the impact of warmer temperatures at lower altitudes. This indicates that altitude plays a more dominant role than snowfall in controlling glacier melt in the region.
Ladakh, which hosts nearly half of India’s glaciers, is highly dependent on glacier meltwater for drinking water, agriculture, and livelihoods. In years of low precipitation, glacier melt becomes the primary water source. Still, Ladakh is one of the least explored glaciated areas in the Himalayas, with few long-term field studies available. This study, which uses hands-on methods such as stake-based tracking and precise GPS tools, offers valuable direct evidence about how glaciers move in this region.
The authors urge regular monitoring and wider research efforts to better understand what drives glacier changes. They also stress the importance of looking at factors like sunlight, wind, and shifting forms of precipitation, all of which may affect glacier melting. As climate change continues to alter the Himalayan ice landscape, their findings highlight that local differences are important; even glaciers close together can behave uniquely. Therefore, tailored research is essential for managing water resources and developing climate adaptation strategies in vulnerable mountain environments.
