Antarctic ice bridge snaps
A view of the leading edge of the remaining part of the Larsen B ice shelf that extends into the northwest part of the Weddell Sea is seen in this photo taken in March, 2008.
One Antarctic ice shelf has quickly vanished, another is disappearing and glaciers are melting faster than anyone thought due to climate change, U.S. and British government researchers reported last week.
They said the Wordie Ice Shelf, which had been disintegrating since the 1960s, is gone and the northern part of the Larsen Ice Shelf no longer exists. More than 3,200 square miles (8,300 square km) have broken off from the Larsen shelf since 1986.
On Saturday, an ice bridge connecting a vast Antarctic ice shelf to two islands shattered. Satellite images from the European Space Agency show a 40-kilometre-long strip of ice, linking the Charcot and Latady islands to the Wilkins Ice Shelf, snapped at its narrowest point.
Scientists fear the collapse will allow ocean currents to wash away more and more of the shelf. They speculate the northern half of the shelf, which is roughly the size of Jamaica, could eventually break free of the Antarctic Peninsula and become a giant iceberg.
The Wilkins Ice Shelf has been moving since the 1990s, but experts say this is the first time one of the links apparently keeping it in place has crumbled. They suspect climate change is responsible for the collapse of the bridge.
“The rapid retreat of glaciers there demonstrates once again the profound effects our planet is already experiencing — more rapidly than previously known — as a consequence of climate change,” U.S. Interior Secretary Ken Salazar said in a statement.
“This continued and often significant glacier retreat is a wakeup call that change is happening … and we need to be prepared,” USGS glaciologist Jane Ferrigno, who led the Antarctica study, said in a statement. “Antarctica is of special interest because it holds an estimated 91 percent of the Earth’s glacier volume, and change anywhere in the ice sheet poses significant hazards to society,” she said.
In another report published in the journal Geophysical Letters, the National Oceanic and Atmospheric Administration reports that ice is melting much more rapidly than expected in the Arctic as well, based on new computer analyses and recent ice measurements.
The U.N. Climate Panel projects that world atmospheric temperature will rise by between 1.8 and 4.0 degrees Celsius because of emissions of greenhouse gases that could bring floods, droughts, heat waves and more powerful storms.
As glaciers and ice sheets melt, they can raise overall ocean levels and swamp low-lying areas.
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