Earth Snapshot RSS Feed Twitter

Posts tagged Ronne Ice Shelf

Glaciers and Ice Rises in Antarctica

78S 33.7W

August 6th, 2009 Category: Snapshots

Antarctica - June 30th, 2009

Antarctica - June 30th, 2009

Both glaciers (upper right) and ice rises (lower right) can be observed in this view of Antarctica between the Ronne Ice Shelf and Queen Maud Land. A glacier is a large mass of ice moving slowly over some land surface or down a valley, formed over long periods from the accumulation of snow in areas where the amount of snow that falls exceeds the amount that melts.

While glaciers can be found on all continents except Australia, ice rises are found only on the ice shelves of Antarctica, mostly on the Ronne Ice Shelf. The largest ice rises exceed dimensions of 50 by 200 km, or 10 000 kmĀ² in area.

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.

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.