The Larsen B ice shelf covered more than 3,000 square kilometers and was {{U}}(36) {{/U}} meters thick until its northern part {{U}}(37) {{/U}} in the 1990s. Three years ago, the central part also broke up.
An international team of researchers used data collected from six {{U}}(38) {{/U}} near the former ice shelf to show the shelf had been {{U}}(39) {{/U}} for at least {{U}}(40) {{/U}} years or since the last ice age.
The {{U}}(41) {{/U}} therefore goes beyond what would be expected naturally at the time. Rather, the {{U}}(42) {{/U}} is likely the result of {{U}}(43) {{/U}} due to melting from underneath, as well as short-term {{U}}(44) {{/U}} from global climate change, the researchers suggest.
Then in five years, the shelf shrunk by {{U}}(45) {{/U}} square kilometers, say scientists who found the break up caused changes in {{U}}(46) {{/U}} in the area.
"As the ice shelves are disintegrating, the {{U}}(47) {{/U}} that are feeding them from the land are {{U}}(48) {{/U}}," said Robert Gilbert, a {{U}}(49) {{/U}} at Queen's University in Kingston, Ont.
Glaciers are no longer being held back from the ice shelf, and are pushing {{U}}(50) {{/U}} into the sea, said Gilbert, one of the co-authors of the study in {{U}}(51) {{/U}} of the Journal Nature.
As the glaciers melt, global sea levels could change more than {{U}}(52) {{/U}}, he said. Flooding could result in {{U}}(53) {{/U}}.
Scientists are now watching to see if the {{U}}(54) {{/U}} of the Larsen ice shelf, the coldest part of {{U}}(55) {{/U}}, is going to break up.