Global glaciers recorded another year of net ice loss in 2025 marking the fourth consecutive year in which every major glaciated region experienced a decline in ice mass according to the World Meteorological Organization (WMO) State of Global Water Resources 2025 report.
Between October 2024 and September 2025, glaciers worldwide lost an estimated 408 ± 132 gigatonnes of ice equivalent to about 1.1 ± 0.4 millimetres of sea level rise the report said.
Six of the seven largest annual glacier mass losses on record have occurred within the past seven years. Central Asia, South Asia West, the Russian Arctic, Iceland, and Western Canada and the United States recorded some of their most negative annual mass balances in 2025.
The WMO said mountain glaciers lost 6.2 per cent of their ice mass between 2000 and 2025, with some regions experiencing substantially larger losses over longer periods.
In Russia’s central Altai region, for example, glaciers have lost about 271.7 square kilometres, or 40.2 per cent, of their area since the 1950s. Around 93.8 square kilometres or 18.8 per cent, of that loss occurred after 2001 with the South Chuya range experiencing particularly strong declines.
The report said glacier ice loss has accelerated since the 1990s and particularly after 2000. The trend is largely linked to increasingly strong summer melting that has exceeded winter accumulation across many regions.
Some regions may have passed ‘peak water’
The continuing decline is also affecting the seasonal water contribution from glaciers. The report noted that regions with relatively small glaciers, including the Caucasus, western Canada and the United States and central Europe, have recorded little increase or even a decline in minimum summer runoff despite continued annual glacier mass loss.
According to the WMO, this could indicate that these areas have already reached “peak water” the point at which glacier melt produces its maximum contribution to runoff before declining as the ice reserve becomes smaller.
The continued loss of glacier mass therefore has implications beyond sea level rise. Mountain glaciers act as freshwater stores, releasing meltwater into rivers and downstream ecosystems. The WMO warned that their sustained decline represents a reduction in global freshwater resources.
The findings underline the growing impact of warming on mountain ice reserves and suggest that continued glacier loss could increasingly affect both seasonal water availability and communities dependent on glacier-fed rivers.