A Glacier Is a River That Moves in Slow Motion
A glacier is a mass of ice that flows under its own weight. It behaves like a river, and it leaves the landscape rearranged behind it.
A glacier is a body of ice thick enough to move under its own weight, carrying rock as it goes. It really does flow: ice deep inside deforms like slow treacle while the brittle surface cracks into crevasses. Where a glacier meets the sea it *calves*, dropping icebergs.
- A slowly moving mass of ice. *The glacier has retreated a kilometre.*
- Glacial — of a glacier, or extremely slow. *At a glacial pace.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | glacier | An alpine glacier. |
| Plural | glaciers | Shrinking glaciers. |
| Adjective | glacial | Glacial ice. |
| Adverb | glacially | Moving glacially. |
| Noun | glaciation | The last glaciation. |
How it is used in a sentence
- The glacier has lost a third of its mass since 1980.Standard in climate reporting.
- Progress has been glacial.Figurative, always a complaint.
- The valley was carved by a glacier.U-shaped valleys are the signature.
Glacier vocabulary
- Crevasse — a deep crack in the surface ice
- Moraine — the rock and debris a glacier pushes or drops
- Calving — ice breaking off into water as icebergs
- Terminus — the front end of the glacier
- Erratic — a boulder carried far from its origin and left behind
From French *glacier*, from *glace*, ice, from Latin *glacies*. The word entered English in the eighteenth century, when travellers began describing the Alps to readers at home.
How fast does a glacier move?
Typically a few centimetres to a metre a day, though some surging glaciers move far faster for short periods.
Glacier or ice sheet?
An ice sheet is a glacier so large it covers a continental area, as in Greenland and Antarctica. All ice sheets are glaciers; most glaciers are not ice sheets.