Hindu Kush Himalayas facing severe glacier loss

The Hindu Kush Himalayas (HKH) are facing a huge glacier loss, more than the global average, with mass loss 65% higher than previous decades. This is according to a new United Nations report released on the World Day for Glaciers, 21 March 2025.

The report, ‘The Urgent Need to Preserve Glaciers in a Warming World’, highlights that globally, glaciers are melting at an unprecedented rate, with ice loss accelerating over the recent two decades. Within just 23 years starting year 2000, more than 215,000 glaciers have lost an annual average of 273gigatonnes of ice, with losses accelerating by 36% between 2012 and 2023 compared to the previous decade. Glaciers are now, in fact, losing more mass than the Greenland or Antarctic ice sheets.

As per a ‘Down to Earth’ (DTE) analysis, the Asia-Pacific region is home to some of the highest mountains and most extensive glacier systems and is among the most vulnerable to climate change. Spanning five million km2 of high mountains, the region contains approximately 100,000 km2 of glaciers.

Glaciers — moving masses of ice that are also considered freshwater reservoirs, the report points out, serve as vital components of climate and hydrological systems, sustaining ecosystems, agriculture and human populations. However, the Introduction to the report warns that climate change and other drivers have accelerated glacier melt, threatening water security, biodiversity and regional economies. It is crucial to recognize the environmental, social and economic significance of glaciers and the urgent need for cooperation for their preservation.

The Introduction adds that glaciers hold around 69% of the world’s freshwater and function as essential water towers that regulate river flows in major mountain regions such as the Himalayas, Andes and Alps. During dry seasons, glacial meltwater helps maintain agricultural activities, generate hydroelectric power and offers drinking water supplies. They also provide essential ecosystem services, shape unique habitats, support life in high-altitude regions, regulate local climates, support biodiversity resilience and hold cultural significance.

After Earth’s two poles, the report states, the HKH – the ‘Third Pole’ – holds the largest glacier concentration. Here, glaciers, life and livelihoods are closely intertwined. These glaciers feed 10 major rivers, including the Ganga, Indus and Brahmaputra, and support the livelihoods of over 1.5 billion people across South Asia. Glaciers and glacier lakes also host unique microbial communities, while high-altitude microclimates foster endemic plants, animals and specialized ecosystems such as peatlands. As ice retreats, new vegetation areas also emerge, potentially increasing primary productivity and species richness due to warmer temperatures. However, changes and glacial retreat pose serious biodiversity threats due to habitat loss/degradation, unstable slope development, altered water cycles and invasive species, often leading to ecosystem services and function declines.

Apart from sea-level rise, melting glaciers are driving the rapid growth of glacial lakes. In just 28 years since 1990, these grew in volume by 48% and saw a number and area increase by more than 50%. This rapid expansion raises the threat of glacial lake outburst floods; a most perilous risk specially in High Mountain Asia, where approximately 1 million people reside within just 10 kilometres of a glacial lake. Moreover, projections also indicate that the frequency of such events could increase threefold in the coming decades, underscoring the urgent need for preparedness and mitigation efforts.

The DTE analysis points out that how the report stresses that water governance in mountain regions is significantly weaker than in lowlands. The HKH lacks effective transboundary cooperation, with mutual distrust a key barrier to data sharing. The report spelled out six transboundary actions for the HKH region, according to the DTE analysis. First, cooperate at all levels for sustainable and mutual benefits. Second, recognize and prioritize the uniqueness of the people. Third, take concerted climate action at all levels to keep global warming to 1.5°C by 2100. Fourth, take accelerated actions to achieve the Sustainable Development Goals and nine mountain priorities. Five, enhance ecosystem resilience, halt biodiversity loss and land degradation. Six, engage in regional data- and information-sharing, and science and knowledge cooperation. The report also recommended incentives for communities protecting watershed areas crucial for hydropower, drinking water and tourism, through payments for ecosystem services. Finally, it highlighted the urgent need for increased funding and support for mountain communities.