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I'm Ryan Walker. I work here at the Cryospheric Sciences Lab.

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I work on computer simulations of the

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Antarctic and Greenland ice sheets.

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to project how much of the ice is going from

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land into the ocean because it's possibly

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an important contributor to sea level rise under climate change.

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My name is Christine Dyer.

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I'm researching sub-antarctic lake developments,

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so using numerical models to see how water

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builds up and depletes underneath the Antarctic ice sheets.

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So we went to the new South Korean research station

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Jang Bogo at Terra Nova Bay not too far from

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the United States McMurdo base.

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The Korea Polar Research Institute

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fed and housed us for five weeks and

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provided helicopters and worked with us.

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It was something that we absolutely could not have

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done without them.

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In this first study, we were looking at how the ocean

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tides affect the motion both horizontally and vertically

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of the Nansen Ice Shelf.

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Examining how the ice shelf responds to tides

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helps us get at the dynamics of how the ice flows and

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we're hoping will help future computer simulations.

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In order to get over to the Nansen Ice Shelf

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you fly over extremely dramatic cliffs,

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very large areas of ice cravassing.

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So it's quite spectacular on the way over.

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There was one particular moment, actually,

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when we first arrived to our tilt meter site.

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There was no wind at all and

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there was quite a lot of snow around.

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And the most poignant thing I think was the silence.

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When the helicopter shut down, nobody was talking.

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You could not hear a single thing and that's such

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an usual thing to be able to find in the world.

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No plane noises, no electricity noises, just absolutely nothing.

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And it was one of the most spectacular places I've ever been.

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The Antarctic ice sheet is flowing under its own weight

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spreading out from the center of the continent out

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to the edges and when it reaches the ocean

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it goes afloat as ice shelves.

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And where you have ice shelves

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that are in bays where the ice contact with the rock walls

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this friction acts to hold back the ice flow,

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so in some sense

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these smaller ice shelves are like corks.

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So as soon as you remove them, there's nothing preventing

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the ice mass from moving quick down.

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If these calve off, if these break off

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right back to where the ice is resting on land

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it can speed up dramatically and it's particular worry

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at the moment that the ice shelves around the Antarctic

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are going to break up and then we're going to see

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an unprecedented speed up in the ice coming out

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of the center of the ice sheet.

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