begin quote from:
An
iceberg almost the size of Delaware has broken away from Antarctica,
scientists said Wednesday. The massive iceberg, measuring 5,800 square
kilometers and weighing more …
Massive iceberg breaks off Antarctic Peninsula, scientists say
An iceberg almost the size of Delaware has broken away from Antarctica, scientists said Wednesday.
The massive iceberg, measuring 5,800 square kilometers and weighing more
than 1 trillion metric tons, broke off, or calved, from the Larsen C Ice Shelf
on the Antarctic Peninsula sometime Monday through Wednesday, according
to scientists at the University of Swansea in England and at the British Antarctic Survey in Wales.
The iceberg is one of the largest on record.
For years, the research teams have been monitoring a vast rift in the ice shelf, using European Space Agency satellites. They said the iceberg has been close to calving for months.
"The iceberg is one of the largest recorded, and its future progress is
difficult to predict," he added. "It may remain in one piece but is more
likely to break into fragments. Some of the ice may remain in the area
for decades, while parts of the iceberg may drift north into warmer
waters."
Scientists said the giant iceberg, which will likely be named A68, was
floating before it split off, so there will be no immediate impact on
sea levels. But the calving left the Larsen C Ice Shelf reduced in area
by more than 12 percent, leaving the "landscape of the Antarctic
Peninsula changed forever."
The Larsen A and B ice shelves, which were farther north on the Antarctic Peninsula, collapsed in 1995 and 2002, respectively.
"This resulted in the dramatic acceleration of the glaciers behind them,
with larger volumes of ice entering the ocean and contributing to
sea-level rise. If Larsen C now starts to retreat significantly and
eventually collapses, then we will see another contribution to sea level rise," said David Vaughan, a glaciologist and the director of science at the British Antarctic Survey.
Both research teams said they don't believe man-made climate change is causing the large icebergs to break off Antarctica.
"However, around the Antarctic Peninsula, where we saw several decades
of warming through the latter half of the 20th century. We have seen
these ice shelves collapsing and ice loss increasing," Vaughan said.
"There are other parts of Antarctica that are losing ice to the oceans,
but those are affected less by atmospheric warming and more by ocean
change."
"Larsen C itself might be a result of climate change, but in other ice
shelves, we see cracks forming, which we don’t believe have any
connection to climate change," he added.
Although the giant calving is being considered a natural event,
scientists said the ice shelf is now in an extremely precarious
position.
"This is the furthest back that the ice front has been in recorded
history. We're going to be watching very carefully for signs that the
rest of the shelf is becoming unstable," Luckman said.
"In the ensuing months and years, the ice shelf could either gradually
regrow or may suffer further calving events, which may eventually lead
to collapse. Opinions in the scientific community are divided," he
added. "Our models say it will be less stable, but any future collapse
remains years or decades away."
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