Greenland Ice Flights

1. 0:04My name's Dave Eastmont.
2. 0:13I'm the mission manager for Wallops aircraft at this time. My previous experience
3. 0:17has been with the P-3. I've done DC-8 flights I've done Aerosonde UAV flights.
4. 0:21and C-130 flights. I've probably got upwards to about 4,000 hours in the back of the plane.
5. 0:30My name's Bill Krabill. I'm the project scientist for Operation Ice Bridge. And I've been flying missions
6. 0:38like this to Greenland since 1991.
7. 0:42The aircraft behind me is NASA's P-3 research aircraft. It's used as a platform
8. 0:51for various remote sensors. And we're going to be using it in Greenland this year, as we have most years since 1991
9. 0:59to collect a suite of measurements to tell the scientists the thickness of the ice and how fast it's flowing
10. 1:08out to the ocean. And what we're observing is the decade of the '90s was exhibiting very
11. 1:16small changes. If we saw a half a meter to a meter
12. 1:20per year of thinning, that was a pretty large number in that time
13. 1:24frame. But since the turn of the century, we're seeing the same glaciers now thinning at 15, and 20, and 25 meters
14. 1:33per year. So there's some very drastic changes taking place up in Greenland.
15. 1:37The additional work that we'll be doing for Operation Ice Bridge will be to follow the exact
16. 1:46orbit paths on the surface that ICESat has followed
17. 1:50in the past and will follow in the future and that ICESat II would follow when it gets launched in 2015.
18. 1:58It does a very nice job of global coverage particularly of Antarctica that's quite remote and very difficult to get to with
19. 2:06an airplane. So whereas the typical flights that we would make in the past are focused, targeted towards the outlet
20. 2:14glaciers, we'll now also do the same kinds of measurements
21. 2:18that a satellite would, and this sort of ties the two projects together.
22. 2:22I'm Jim Yungle, I'm a lead engineer on the NASA Airborne Topographic Mapper Project.
23. 2:30It measures the elevation of the terrain the aircraft flies over
24. 2:35by firing pulses of laser light from the aircraft to the ground and back. Those pulses are scanned in an oval scan
25. 2:43and this allows us to map a swath of terrain underneath the aircraft, and it allows us to return in a future
26. 2:51year and repeat those measurements pretty accurately.
27. 2:55We're concerned with the icesheets of the world because to some degree they control sea level.
28. 3:03Greenland is the second-largest ice sheet in the world. It contains enough
29. 3:07ice and snow that if it were to melt it would raise sea levels
30. 3:12substantially, maybe as much as 20 feet in this area. You can imagine Greenland
31. 3:16as a huge ice cube that's a thousand miles long and 400 miles wide and two miles thick in the center.
32. 3:25It buffers global climate, regional climate so that changes in the ice sheet become very important indicators of global climate change.
33. 3:42It's something you have to experience...
34. 3:46we'll fly these patterns at 1,500 feet,
35. 3:50above the ground level. And you get up on the ice sheet it's like flying over the clouds.
36. 3:54And you look down and it's white, fluffy sometimes -- it just looks like a cloud.
37. 3:58You have to keep in your head that it's solid underneath you.
38. 4:03Probably one of the neatest things to see is when you're flying
39. 4:07down the glacier toward the ocean, you're at 1,500 feet and just as you hit the ocean
40. 4:12the glacier drops off another thousand feet. No matter now often you do it, it always takes your breath.

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