mountain glacier

Also known as: alpine glacier, valley glacier

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June 17, 2026

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A mountain glacier is a large mass of perennial ice that forms on land from recrystallized snow and shows evidence of flow. These glaciers are distinct from the massive Antarctic and Greenland ice sheets and are typically confined to valleys or cirques.12

Glaciers grow through snowfall and shrink via melting, runoff, or iceberg calving. A balance between accumulation and ablation determines if a glacier expands or recedes. Mountain glaciers can be classified by their shape and location, such as valley glaciers, cirque glaciers, or piedmont glaciers. Their surfaces can exhibit features like snow dunes, sastrugi, sun cups, and crevasses. The transformation of snow into dense glacier ice involves processes like sintering and recrystallization under pressure, which can take thousands of years in polar regions. Glaciers play a role in hydrology by storing and releasing water, influencing streamflow and sediment transport. Changes in glacier mass balance are directly linked to climate fluctuations, leading to advances or retreats that can impact global sea levels.1234567

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glacier
Mountain glaciers
In this discussion the term mountain glaciers includes all perennial ice masses other than the Antarctic and Greenland ice sheets. Those ice masses are not necessarily associated with mountains. Sometimes the term small glaciers is used, but only in a relative sense: a…
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In this discussion the term mountain glaciers includes all perennial ice masses other than the Antarctic and Greenland ice sheets. Those ice masses are not necessarily associated with mountains. Sometimes the term small glaciers is used, but only in a relative sense: a…
Read More

Pleistocene Epoch
Glaciation
…sheets, ice caps, and long valley glaciers was among the most significant events of the Pleistocene. During times of extensive glaciation, more than 45 million square km (roughly 17,400,000 square miles), or about 30 percent of Earth’s land area, was covered by glaciers, and portions of the northern oceans either…
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…sheets, ice caps, and long valley glaciers was among the most significant events of the Pleistocene. During times of extensive glaciation, more than 45 million square km (roughly 17,400,000 square miles), or about 30 percent of Earth’s land area, was covered by glaciers, and portions of the northern oceans either…
Read More

glacial landform
Types of glaciers
…focus on two broad classes: mountain, or valley, glaciers and continental glaciers, or ice sheets, (including ice caps). For information about other types, see the articles ice and glacier.
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…focus on two broad classes: mountain, or valley, glaciers and continental glaciers, or ice sheets, (including ice caps). For information about other types, see the articles ice and glacier.
Read More