SCIENCE REPORT - Pine Island Glacier(在线收听

SCIENCE REPORT

February 20, 2002: Pine Island Glacier

By Jerilyn Watson


This is the VOA Special English Science Report.

Scientists have expressed much interest in the development of a huge new iceberg in Antarctica. This huge ice
island formed when a piece broke off a moving mass of ice called the Pine Island Glacier. The new iceberg was
formed last November. Creation of the new iceberg was the biggest such event ever recorded in the area. As
much ice broke off the glacier as it usually releases in about seven years.

The iceberg is about six-hundred square kilometers. It is four-hundred meters thick. The iceberg now is moving
toward the northwest. Experts say its creation shows that western Antarctica is changing quickly. Experts say
formation of the iceberg is not expected to affect sea levels on Earth. However, it is not clear how it may
influence the climate.

The Pine Island Glacier is the fastest moving glacier on the continent. It releases more ice into Antarctica than
any other glacier. It is in the area of the West Antarctic ice sheet that scientists believe is most likely to break
apart.

American space agency scientist Robert Bindschadler works at the Goddard Space Flight Center in the state of
Maryland. The NASA expert was studying satellite pictures of the Pine Island Glacier in January of last year. He
noted a thin break in its ice. This crack measured about twenty-five kilometers long. It extended more than two-
thirds of the way across the glacier. Satellite photos taken ten months earlier had not shown a crack.

Other agencies that observe the Earth helped NASA watch the crack develop. The researchers used special
instruments to measure its growth. During the first five weeks, it grew very fast. Then the crack grew at an
average of about fifteen meters a day. The last ten kilometers of the cracking area broke off within days. The
iceberg was formed at least six months faster than scientists had expected.

NASA and the United States Geological Survey work together to make maps of Antarctica. Their joint project is
called Landsat Seven. Landsat equipment can see objects as small as fifteen meters across. Before the project
began, many parts of Antarctica had never been seen this well before.

This VOA Special English Science Report was written by Jerilyn Watson.


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