Extensive glacier loss in the coterminous United States

Andrew G. Fountain; Bryce Glenn; Christopher McNeil; Brian Menounos

doi:10.1073/pnas.2600941123

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Extensive glacier loss in the coterminous United States

Andrew G. Fountain·Bryce Glenn·Christopher McNeil·Brian Menounos

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Abstract

Glaciers populate the mountain ranges of the western conterminous United States and despite their importance to alpine hydrology, their area and volume change have never been comprehensively evaluated. Since the mid-Twentieth Century about one-quarter of the glaciers have disappeared and the overall area and volume are reduced by one-third. The pattern of glacier shrinkage suggests most glaciers in the Conterminous US are largely maintained by local topographic influences due to their small size. These results are critical to understanding evolving high alpine hydrology and important to ecosystem processes.

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Proceedings of the National Academy of Sciences Article

Source-reported bounding extent: 36.75770857769582° to 48.89149426931624° latitude; -126.05468375886852° to -101.15719157927896° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Andrew G. Fountain, Bryce Glenn, Christopher McNeil, Brian Menounos. 2026-10-12. Extensive glacier loss in the coterminous United States. https://doi.org/10.1073/pnas.2600941123

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