Glaciers form where winter snows are too deep to fully melt during the warmth of summer. Under these conditions the snowpack grows deeper and more compressed each winter, eventually transforming into clear blue ice. As glacier ice flows slowly downhill, it carries along rocks and debris excavated from the mountains above. In this way, glaciers are not just a part of our nation's most spectacular alpine landscapes; they help to shape them.
Glaciers provide meltwater for mountain rivers, habitat for specialized creatures, travel corridors for brush-weary visitors, and a playground for alpine climbers. Their persistence connects us with a time when ice age mammals roamed the continent, and reminds us of the value of those increasingly rare places where winter still reigns supreme.
Last updated: January 28, 2022