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Scientific Sleighride
Tue Apr 29, 2003
Listen in RealAudio 
Hi, I'm Bryan Yeaton for The Weather Notebook's weekly segment on global climate
change.
While most Americans were opening presents or watching football games over the holidays, 10
men and three women were sledding their way to the South Pole. Despite the 24-hour sunlight,
the Antarctic summer was no holiday for the scientists. They were crossing the West Antarctic
Ice Sheet, where a heat wave is when the temperature climbs close to 0 degrees Fahrenheit.
Minus 40 or 50 is more typical.
This was the first research team since 1957 to cross the heart of the ice sheet. Two tractors
pulled the sleds about 30 miles each day along a route from Byrd Station to the South Pole --
800 miles in all. The team dug snow pits up to 12 feet deep and pulled out cylinders of ice
more than 200 feet long. Like a mini-museum, each ice core shows the state of the climate
hundreds or thousands of years ago. Scientists hope this new data will help them map out how
much snow has fallen over the ice sheet and where the ice is moving. Although the earth as a
whole is warming up, Antarctica presents a mixed picture. The heart of the continent has
actually cooled a bit. Some parts of the ice sheet have become deeper.
Meanwhile, huge chunks of ice continue to break off the edge of Antarctica. If the entire
West Antarctic Ice Sheet broke off and melted, it would raise sea level by about 20 feet
worldwide. Most scientists don't expect this to happen - at least for a few hundred years.
Maybe by then we can figure out how to reverse the problem.
Our series on global climate change is supported by the New England Science Center
Collaborative and the Roy A. Hunt Foundation. Thanks also to Subaru and the National Science
Foundation.
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