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For today’s Geo Quiz head about as far south as you can go. The Transantarctic Mountains span Antarctica … dividing it roughly in half. We’re looking for the half that principally borders on the Pacific Ocean.

It includes the Antarctic Peninsula, the Ross Ice Shelf and the Orville Coast. Taken together, all of this land and ice lies in the Western Hemisphere.

Scientists are heading there as part of Operation Ice Bridge to try to get a better understanding of how climate change is affecting this polar region:

“This part of Antarctica is full of volcanoes, and its covered by the ice sheet that’s most susceptible to ongoing change because the bottom of the ice sheet sits below sea level and the warm ocean waters can reach up and warm that ice.”

We’ll hear more about Operation Ice Bridge in just a minute when we come back with the answer…

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Geo Answer:
We’re going to hear more now about Operation Ice Bridge. It’s a NASA research project aimed at getting a better look at what’s happening on and under West Antarctica.

And West Antarctica — the part of Antarctica that lies in the western hemisphere — is the answer to our Geo Quiz. Climate scientists will soon be flying over this area to survey rapidly changing ice conditions.

Robin Bell is a geophysicist at Lamont Doherty Earth Observatory, listen to the interview:

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MARCO WERMAN:  I’m Marco Werman, this is The World. We’re going to hear more now about Operation Ice Bridge. It’s a NASA research project aimed at getting a better look at what’s happening on and under West Antarctica. And West Antarctica, the part of Antarctica that lies in the western hemisphere, is the answer to our Geo Quiz. Climate scientists will soon be flying over this area to survey rapidly changing ice conditions. Robin Bell is a geophysicist at Lamont Doherty Earth Observatory. So starting any day now, a NASA DC-8 aircraft will buzz over West Antarctica Robin, what are you looking for?

ROBIN BELL:  What we’re looking for is to accurately measure both the top and the bottom of the ice, all those different kinds of ice that fringe Antarctica. The parts that are floating, the parts that are still stuck to the ground.

MARCO WERMAN:  So, we’ve seen dramatic satellite images of course of West Antarctica’s ice sheets collapsing. What is this low altitude flight mission able to do that satellite remote sensing cannot do?

ROBIN BELL:  Almost everything we know about how fast the ice sheets are changing, have come from NASA satellites. We’ve seen those dramatic pictures, but we’ve also measured how the ice surface is dropping, and the ice is speeding up. And we’ve actually even weighed it from space, and it’s losing mass. So we have an idea of how fast Antarctica’s changing, but satellites can’t see through the ice, they can’t see to the bottom. And the aircraft is a unique opportunity to actually see through the ice, and understand why the ice sheets are changing.

MARCO WERMAN:  But even at a low altitude, a plane can actually look under the frozen ice shells and see what’s going on in the water?

ROBIN BELL:  Oh, we have a whole [INDISCERNIBLE] of instruments on the DC-8, that let us look through the ice. One is a radar, similar frequencies to your microwave, and it shoots energy out through the bottom of the plane, and listens to it bounce back, kind of like an echo, and allows us to measure how deep the ice is. That doesn’t work everywhere because sometimes there’s water between the ice, and for that we’ll use gravity to measure what the changing mass is.

MARCO WERMAN:  Why do that now though with the coming summer south of the equator? Doesn’t ice normally break up now anyway?

ROBIN BELL:  Well, the ice goes through an annual cycle, but it’s important that we watch it every year. So we have a sense of how things are changing. So since the satellites aren’t gonna be in place for the next five years as they have been, sending the aircraft down at the same time every year will sort of be like having the ice sheet go for its annual physical.

MARCO WERMAN:  And why just West Antarctica? Is it especially susceptible?

ROBIN BELL:  West Antarctica is most sensitive to melting for two reasons. One is, it’s low sea level, the bottom of it. So it’s sort of more susceptible to global change because the ocean water wan warm the bottom. And the other reason is that this is the part of Antarctica where the ocean currents look like they’re getting up close to the ice sheet, and therefore warming both the surface and the bottom of the ice sheet. This aircraft will fly up and down, the part of Antarctica that are changing the fastest. By better constraining what’s going on at the bottom of the ice sheet, we hope to be able to make better models, so we can predict how the ice sheet will change in the future.

MARCO WERMAN:  Robin Bell, geophysicist at Lamont Doherty Earth Observatory, thanks very much for your time.

ROBIN BELL:  Thank you very much for having me.

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