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Posts tagged Ice Rise

Ice Rises Parallel the Coast of the West Antarctic Ice Sheet

75.8S 53.4W

December 16th, 2009 Category: Snapshots

Antarctica - November 30th, 2009

Antarctica - November 30th, 2009

Three ice rises appear here as long parallel lines near the edge of the West Antarctic Ice Sheet. Ice rises are rounded elevations that form where the ice shelf touches areas in the seabed that are elevated, but nevertheless below sea level.

The ice shelf flows over these higher parts of the seabed and completely covers them with ice. The ice rises formed in this manner are typically 100 to 200 meters high.

Ice Rises on West Antarctic Ice Sheet

78.9S 45.7W

August 20th, 2009 Category: Snapshots

Antarctica - August 16th, 2009

Antarctica - August 16th, 2009

The parallel lines rising up from the flat surface of this part of the West Antarctic Ice Sheet are  phenomena known as ice rises.

These are rounded elevations that form where the ice shelf touches elevated, but nevertheless below sea level, areas in the seabed. The ice shelf flows over the seabed elevation, completely covering it with ice, thereby forming an ice rise. Such ice rises are typically 100 to 200 meters high.

Upon opening the full image, the full length of these ice rises can be observed (bottom), as can cracks along the edge of the ice sheet (top).

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 km² 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.

Linear Patters on West Antarctic Ice Sheet

77.7S 52W

July 11th, 2009 Category: Snapshots

Antarctica - March 29th, 2009

Antarctica - March 29th, 2009

About 98% of Antarctica is covered by the Antarctic ice sheet, a sheet of ice averaging at least 1.6 kilometres (1.0 mi) thick. The continent has about 90% of the world’s ice (and thereby about 70% of the world’s fresh water).

Here, rounded and raised linear patterns are visible on the  West Antarctic Ice Sheet. These are ice rises: clearly defined elevations 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 West Antarctic Ice Sheet has shown signs of increasing mass loss and has been referred to as the ‘Awakened Giant’ (click here for articles and images regarding this loss).