- WASHINGTON (AP) -- A giant iceberg -- bigger than the state of Delaware
-- has broken off an Antarctic ice shelf.
-
- The National Oceanic and Atmospheric
Administration said Thursday that the berg, named A-38, broke off the
Ronne Ice Shelf and is floating adjacent to the shelf.
-
- The iceberg is 92 miles (148 km) long
and about 30 miles (48 km) wide with an area of 2,751 square miles (7,125
sq. km). Delaware has an area of 2,044 square miles (5,294 sq. km).
-
- The new iceberg was sighted by Mary Keller,
a scientist at the National Ice Center in Suitland, Maryland, using satellite
data.
-
- Ice shelves are massive, floating sheets
of snow ice that circle Antarctica. Some scientists believe that the breaking
off, or calving, of icebergs may be an indicator of global warming. The
last known iceberg of this size to calve off a Southern Hemisphere Ice
Shelf was B-9 in the Ross Sea in October 1987. Iceberg names are derived
from the Antarctic quadrant in which they are originally sighted.
-
- Quadrant A includes the Bellinghausen
and Weddell seas and the peninsula extending toward the tip of South America.
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Antarctica Not
Shrinking Scientists Say
- LONDON (Reuters) - Fears that the icy wastes of Antarctica are shrinking
and causing the sea level to rise dangerously are misplaced, scientists
said on Thursday. The team of British, Dutch and American scientists from
University College London, who have been measuring the continent's ice
sheet for the last five years, concluded that most of the ice stored there
was "very stable."
-
- "The icy continent now looks an
unlikely source of rising global sea level this century, making thermal
expansion of the ocean due to global warming, and the shrinking of mountain
glaciers, more likely causes," Professor Duncan Wingham, leader of
the scientific research team, said.
-
- Such is the rate at which the world's
oceans are rising that millions of homes near sea level could be underwater
in two centuries if current predictions are correct, Wingham said.
-
- His team of scientists used space satellites
to determine whether the thickness of the Antarctic ice sheet had changed
over a five-year period between 1992 and 1996.
-
- They found that the Antarctic ice sheet
had changed on average by less than 1 cm (0.4 inches) a year and calculated
that melting within the ice sheet interior had contributed only 1.7 cm
to sea level rise this century.
-
- The sea level this century has risen
18 cm over the past 100 years, Wingham said, adding that scientists in
the past have blamed the Antarctic for some 14 cm of that overall change.
-
- "Sceintists have never really understood
the role the Antarctica has played in this century's rising sea level.
Our research makes it likely that the answer is 'very little'," the
British scientist said.
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