ambience: ice core drilling
We’re listening to the sounds of what is, in effect, a time machine. It’s giving us a glimpse – a mini time capsule – of what the Earth was like half a million years ago. I’m Jim Metzner, and this is the Pulse of the Planet.
In Antarctica, scientists are drilling into the ice sheet, taking core samples. It’s from these bits of subterranean ice that they find evidence of what Earth’s atmosphere was like eons ago.
“We look at the Antarctic ice sheet as like a two-mile thick time machine, and what it does is, it has a record of atmospheric conditions over about a half a million years.”
John Priscu is with the Department of Land Resources and Environmental Sciences at Montana State University in Bozeman.
“So, every year you look at it as maybe five, ten centimeters of snow gets deposited on the surface, and then the next year another five, ten centimeters gets deposited. And it just keeps moving the previous layer down and down, and the ice at the bottom kind of moves off to the side and goes out to the ocean as icebergs. So, as you go down through the ice, you get this very nice chronology of atmosphere for about a half a million years.”
Professor Priscu is part of a team of scientists from around the world that’s drilling though the Antarctic ice to a lake that lies two and half miles beneath the surface.
“If we get into lake- and eventually we hope to in the next five years or so – if we actually get into the lake and sample it, weâ€™ll be sampling an environment thatâ€™s been isolated from the atmosphere for 20 million years or so. And we may find some very unique physiologies of organisms in there. For example, we may see organismal assemblages like we see in the deep-sea vent systems. We just donâ€™t know. Itâ€™s one of the last unexplored frontiers on our planet.”
We’ll hear more about Antarctica’s sub-glacial lakes in future programs. Pulse of the Planet is made possible by the National Science Foundation. I’m Jim Metzner.