Himalayan snow cover could shrink 68% by 2100, scientists warn

DEHRADUN: Nearly 68% of snow cover in the Himalaya could disappear by the end of the century if current warming trends continue, according to a new peer-reviewed study, raising concerns over water security, glacier hazards and climate risks across South and Central Asia. The research, published in the journal Earth Science Reviews, also projects that about 26% of snow cover in the Karakoram region may vanish by 2100, although that range has historically shown greater stability than the rest of the Himalayan system.Conducted by Vishwambhar Prasad Sati and Surajit Banerjee of Mizoram University, the study examines climate-driven changes across the Hindu Kush–Himalaya region, often called the "Third Pole" and the "Water Tower of Asia" because of the vast stores of snow and ice that feed Asia's major rivers.According to the researchers, the region warmed at a rate of 0.2–0.3°C per decade between 1980 and 2020, nearly twice the global average, with parts of the eastern Himalaya warming even faster. Rising temperatures and shifting precipitation patterns are accelerating glacier retreat and reducing snow cover across large sections of the mountain chain. The study found that Himalayan glaciers lost mass at an average rate of 0.37 ± 0.15 metres water equivalent per year between 2000 and 2016, indicating a sharp increase in melting compared with earlier decades.Snow cover decline has been particularly pronounced in the central and eastern Himalaya, where nearly 30% of snow cover has disappeared since the 1990s, largely because of declining snowfall. In contrast, the Karakoram region has shown relative stability or slight gains in snow cover, a phenomenon often referred to as the "Karakoram anomaly", linked to winter precipitation from westerly weather systems. Despite this local variation, scientists say the broader trend across the region points to a steadily shrinking cryosphere.The warming climate is also transforming the landscape in other ways. As glaciers melt, glacial lakes are expanding rapidly, raising the risk of glacial lake outburst floods (GLOFs). In the central Himalaya alone, the number of glacial lakes rose from 1,160 in 1977 to 2,168 by 2010, while 697 GLOF events were recorded across the wider region between 1833 and 2022.Researchers also documented increasing avalanche activity and thawing permafrost, both of which destabilise mountain slopes and heighten the risk of landslides and rockfalls. Between 1982 and 2022, at least 681 major avalanche events were recorded, causing more than 3,100 deaths.Beyond the mountains, the implications extend to hundreds of millions of people downstream. Glacier and snowmelt contribute 33–42% of annual flow in major river systems such as the Indus, Ganga and Brahmaputra, rivers that sustain the livelihoods of around 869 million people across South and Central Asia.The researchers warn that many river basins could reach "peak meltwater" around 2050, after which flows may begin to decline as glaciers shrink further. They call for stronger monitoring of the region's cryosphere, climate-resilient infrastructure and greater regional cooperation to manage risks in one of the world's most critical high-mountain water systems.