How scientists track glacier health over decades

An illustrator explains the mechanics of mountain glaciers, showing how high-elevation snowfall compresses into ice and melts downstream.

How Mountain Glaciers Actually Move

20 years of glacier measurements reveal steady ice loss

USGS researchers measure winter snow accumulation against summer ice loss to track long-term glacier decline.

Glaciers provide critical water for surrounding ecosystems, wildlife, and human communities downstream.

[00:14] How Mountain Glaciers Actually Move
[00:35] 20 Years of Measuring Sperry Glacier
[01:11] Why Glacier Meltwater Matters Downstream