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Year 2001 Icebergs
December 3, 2001-The University of Wisconsin
Antarctic Meteorology Research Center
(AMRC) released this image on December 3,
2001. NOAA-12 infrared image showing B-15A and C-16 along with the fast ice
stretching from the Drygalski Ice Tongue to Ross Island. Sea ice continues to
fill the area between the Drygalski Ice Tongue and the B-15A iceberg.
November 15, 2001, Washington
D.C.--
The National Ice Center (NIC)
discovered an iceberg newly calved from the Pine Island Glacier (Figure 1). The
Pine Island Glacier is a large sheet of glacial ice and snow extending from the
Antarctic mainland into the southern Amundsen Sea.
National
Ice Center
This image sequence shows the
break-off of a large tabular iceberg from the Pine Island Glacier in West
Antarctica. This event occurred sometime between November 4th and 12th, 2001,
and provides powerful evidence of rapid changes underway in this area of
Antarctica. The three images were acquired by the vertical-viewing (nadir)
camera of the Multi-angle Imaging SpectroRadiometer instrument aboard NASA’s
Terra spacecraft. The dimensions of the iceberg are approximately 42 kilometers
by 17 kilometers (26 miles by 11 miles). Pine Island Glacier is the largest
discharger of ice in Antarctica and the continent’s fastest moving glacier.
It is located in an area of the West Antarctic ice sheet that is believed to be
the most susceptible to collapse, making the evolution of this glacier of great
interest to the scientific community. In mid 2000, a large crack formed across
the glacier, located at 75 degrees south latitude, 102 degrees west longitude.
The crack took the glaciological community by surprise, particularly the
rapidity of its growth, which was not expected to reach the other side of the
glacier until sometime in 2002. Data gathered from other imaging instruments
indicated the crack in the shelf ice was growing at a rate averaging 15 meters
(16 yards) a day and was rotating about one percent per year at the seaward
margin of the rift. The images show that the last 10-kilometer (7-mile) segment
that was still attached to the ice shelf snapped off in a matter of days. The
first image in this set was captured in late 2000, early in the development of
the crack. The second and third views were acquired in November 2001, just
before and just after the formation of the new iceberg. The newly hatched berg,
the largest such event ever witnessed in this region, represents nearly seven
years of ice outflow from Pine Island Glacier released to the ocean in a single
event. The climatic significance of this calving event is not yet clear.
However, when combined with previous measurements from this instrument and data
from other instruments cataloguing the retreat of the glacier’s grounding
line, its accelerating ice flow, and the steady decrease in the sea ice cover
in front of the glacier, it provides scientists with additional evidence of
rapid change in the region. Credit: NASA/GSFC/LaRC/JPL, MISR Team.
This new iceberg is named
B-21and is currently located at 74.076S/ 102.00W. Iceberg B-21, roughly 22NM
long and 8NM wide, covers an area of approximately 233 square statute miles.
National Ice Center analyst AG1 Oliver Jedlick spotted the new berg while
performing a weekly update of Antarctic Iceberg Database. AG1 Jedlick located
the berg using the satellite image shown above from the Defense Meteorological
Satellite Program's (DMSP) Operational Line Scan (OLS) Visible sensor.
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