Declining West Himalayan Glaciers Result in Decreased Water Supply Should Warming Continue

Environmental Research Climate, 3 July 2026

Glaciers in the Western Himalayas store vast freshwater reserves that supply rivers supporting drinking water, agriculture, hydropower, and ecosystems for hundreds of millions of people downstream. Over the past four decades, the region warmed at twice the rate of the broader Indian landmass. Using glacier models under global warming levels of 1.5, 2, 3, and 4°C, this study found that total glacier meltwater across the Western Himalayas is projected to peak near 2°C of global warming before declining as glaciers continue to shrink. The response varies by glacier size: small glaciers are already past peak meltwater and begin producing less melt by 1.5°C, medium-sized glaciers peak near 2°C, and large glaciers continue increasing meltwater until around 3°C before also declining. As warming increases, more precipitation falls as rain instead of snow, reducing the snowfall that replenishes glaciers. These findings underscore the importance of limiting warming well below 2°C to help sustain glacier-fed water supplies, as warming beyond this threshold leads to progressively declining meltwater availability and continued glacier loss.

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