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You are actually radioactive and everything alive is unexpected.
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Welcome to the Inquiry.
I'm William Crawley.
Each week, one question, four expert witnesses, and an answer.
An iceberg is on the move.
But this is no ordinary iceberg.
It's a floating colossus, the biggest iceberg currently at sea.
Known as a 23A, it broke away from an ice shelf on the Antarctic more than 35 years ago before becoming stuck in the Southern Ocean.
But in 2020, that decades long stillness was broken.
And now a trillion tons of frozen pure water is riding the currents of Iceberg Alley.
So this week we're asking, what can the world's biggest iceberg tell us?
Part one, Birthing.
An iceberg is a piece of ice that's broken off from one of our two ice sheets on the Earth.
So there's the Antarctic ice sheet and the Greenland ice sheet and sometimes smaller glaciers that exist around the coast of places like Canada and Russia.
Dr.
Catherine Walker is a glaciologist with the Woods Hole Oceanographic Institution in Massachusetts in the United States.
And like any material, those tend to break off into chunks when they get to a certain stress level.