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Ocean Cores
Tue Feb 24, 2004
Listen in RealAudio 
Hi, I'm Bryan Yeaton and this is The Weather Notebook's weekly segment on global climate
change. A team of 28 researchers from across the globe have discovered, through ocean coring,
the first-ever continuous record of climatic conditions 50 million years ago. Jeff Rice
reports.
Think of it as a floating telescope.
ML: The drill ship is an observatory just the way the Hubble space telescope is an
observatory.
Out in the middle of the Pacific Ocean, paleooceanographers like Dr. Mitch Lyle of Boise State
University are able to peer back millions of years by drilling into the mud on the ocean
floor.
Lyle is especially interested in the Eocene, a time 50 million years ago when there were no
polar ice caps on earth. There were forests growing in Antarctica...
ML: And actually, there were crocodiles and palm trees in Wyoming.
The ocean sediments hold the answers to many key questions about the earth's changing climate.
Scientists can tell things like wind patterns from dust distribution. They can look at
fossilized plankton to gauge the earth's temperatures. But it's no easy trick, as Lyle
experienced on a recent drilling expedition in the Pacific.
ML: We were working in 15,000, 16,000 feet of water, so if something stuck in the end of the
pipe it meant 24 hours to pull everything up.
Scientists will typically spend two months at sea gathering soil samples at a cost of $50,000
a day. Ocean drilling differs from its cousin, ice coring, because it allows scientists to
look much farther back in the geologic record.
ML: The basic reason is soil doesn't melt.
By looking at conditions from extremely warm periods like the Eocene, scientists are hoping to
create more accurate models of current global warming trends.
Jeff Rice comes to us from Idaho. Our series on global climate change is supported by the New
England Science Center Collaborative and the Roy A. Hunt Foundation.
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