Salmon glacier in an eroded valley in British Columbia, Canada. (Image: Wikimedia Commons)
Climate change and “unsustainable human activities” are driving “unprecedented changes” to mountains and glaciers, threatening access to fresh water for more than two billion people, a UN report warns.
The 2025 UN world water development report finds that receding snow and ice cover in mountain regions could have “severe” consequences for people and nature.
Up to 60% of the world’s freshwater originates in mountain regions, which are home to 1.1bn people and 85% of species of birds, amphibians and mammals.
The report highlights a wide range of impacts, including reduced water for drinking and agriculture, stress on local ecosystems and increased risk of “devastating” glacial lake outburst floods (GLOFs).
It also notes the deep spiritual and cultural connections that mountain-dwelling communities around the world have with mountains and glaciers, from India’s Hindu Kush Himalaya to Colombia’s Sierra Nevada de Santa Marta.
One expert tells Carbon Brief that glacier loss is already causing “loss of life, loss of livelihood and most importantly of all, the loss of a place that many communities have called home for generations”.
The report showcases a range of adaptation responses that communities are already implementing, including changing farming practices, producing better water storage systems and improving early warning systems for floods and landslides.
It also stresses the need for further funding and adaptation, as well as the importance of Indigenous knowledge and international collaboration.
Water towers
The annual UN world water development report unpacks a different aspect of “water and sanitation” each year and gives policy recommendations to decisionmakers. This year’s report focuses on mountains on glaciers, because 2025 has been designated by the UN as the “international year of glaciers’ preservation”.
Mountains are often called the world’s “water towers” due to their crucial role in the global water cycle.
