Krulwich Wonders... NPR Science Correspondent Robert Krulwich demystifies dense and difficult science.
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John James Audubon/University of Pittsburgh/ Wikimedia Commons
Courtesy of Monroe County Public Library
It's been there for thousands, maybe tens of thousands of years — a huge, solid, endless mass of white ice. Then, all of sudden ("It's starting, Adam," says an onlooker) there's a crack, then another, and whoosh, an immense field vanishes — splits, splits again, and right before your eyes (you've got to see this) sinks into the sea. This is how ice leaves our planet.
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