Ice rise

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Sketch of the Antarctic coast with glaciological and oceanographic processes, showing ice rises within ice shelf

An ice rise is a clearly defined elevation of the otherwise totally flat ice shelf, typically dome-shaped and rising 100 to 200 meters above the surrounding ice shelf. An ice rise forms where the ice shelf touches the rocky seabed because of an elevation that does not reach sea level. Otherwise it would be an island instead of an ice rise, by definition. The appearance of an island within and totally covered by the ice shelf, and an ice rise may the same, and the difference may be established by elaborate measurements only. The ice shelf flows over this obstacle, which is completely covered by ice, with no rock exposed, thereby forming an ice rise. The resulting tension forms crevasses around the ice rise. Although ice rises are typically located within the ice shelf area, they can partially face the open sea.

Ice rises are found only on the ice shelves of Antarctica, mostly on Ronne Ice Shelf. The largest ice rises exceed dimensions of 50 by 200 km, or 10 000 km² in area. Some ice rises are incorrectly called islands, but also a few totally ice-covered islands within an ice shelf are also called ice rises, most notably Berkner Island and Lyddan Island.

Ice rises, grouped by ice shelf, clockwise starting in East Antarctica: