Peering under the ice of a collapsing polar coast
Low-level aerial surveys aim to understand rapid Antarctic melting
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  IMAGE: The cabin of a DC-8 aircraft has been converted for instruments and engineers.
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Starting this month, a giant NASA DC-8 aircraft loaded with geophysical instruments and scientists will buzz at low level over the coasts of West Antarctica, where ice sheets are collapsing at a pace far beyond what scientists expected a few years ago. The flights, dubbed Operation Ice Bridge, are an effort by NASA in cooperation with university researchers to image what is happening on, and under, the ice, in order to estimate future sea-level rises that might result.
Since 2003, laser measurements of ice surfaces from NASA’s ICESat satellite have shown that vast ice masses in Greenland and West Antarctica are thinning and flowing quickly seaward. Last month, a report in the journal Nature based on the satellite’s measurements showed that some parts of the Antarctic area to be surveyed have been sinking 9 meters (27) feet a year; in 2002, one great glacial ice shelf jutting from land over the ocean on the Antarctic Peninsula simply disintegrated and floated away within days.
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 IMAGE: Antarctica’ Larsen Ice Shelf has deteriorated in recent years, and it is one target of the flights.
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NASA’s satellite reaches the end of its life this year, and another will not go up until 2015; in the interim, Operation Ice Bridge flights will continue and expand upon the satellite mission. In addition to lasers, the plane will carry penetrating radars to measure snow cover and the thickness of ice to bedrock, and a gravity-measuring system run by Columbia University’s Lamont-Doherty Earth Observatory that will, for the first time, plot the geometry and depth of ocean waters under the ice shelves. The gravity study is seen as key because many scientists believe warm ocean currents may be the main force pulling the ice sheets seaward, melting the undersides of ice shelves and thus removing the buttresses that hold back the far greater masses of ice on land.
“What our colleagues see from modeling of these glaciers is that warm ocean water is providing the thermal energy to melt the ice,” said Lamont geophysicist Michael Studinger, a co-leader of the gravity team who will be on some of the flights. “To really understand how the glaciers are going to behave, we need the firsthand measurements of water shape and depth.” Earlier this year, an icebreaker cruise co-led by another Lamont scientist, Stan Jacobs, sent an automated submarine to look under the region’s Pine Island Glacier, which has been moving forward rapidly in recent years. Its bed, where the ice contacts rock, is below sea level, and scientists are concerned about what would happen if a sudden large movement were to introduce seawater underneath. The plane flights, over some six weeks starting Oct. 15, are aimed at providing a wider-scale picture of Pine Island and other targets.
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 IMAGE: Ice shelves, extending from land over the ocean, form the ends of many Antarctic glaciers, making them vulnerable to warm ocean currents. Radar signals can measure the depth of ice,…
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For each of some 17 flights, the 157-foot DC-8–too big for runways on Antarctic bases–will make an 11-hour round trip from Punta Arenas, Chile, with two-thirds of each trip spent getting to Antarctica. There, the plane will fly survey lines as low as 1,000 feet, some of them along sinuous glacial valleys that may test the nerves of both pilots and scientists. Some flights will investigate the region’s open sea ice, which also seems to be in decline. The campaign will cost about $7 million.
“We learned how fast the ice sheets are changing from NASA satellites,” said Lamont geophysicist Robin Bell, who is helping lead the project. “These flights are a unique opportunity to see through the ice, and address the question of why the ice sheets are changing.”
“A remarkable change is happening on Earth, truly one of the biggest changes in environmental conditions since the end of the ice age,” said Tom Wagner, cryosphere program scientist at NASA headquarters in Washington. “It’s not an easy thing to observe, let alone predict what might happen next. Studies like this one are key.”
Investigators from the University of Washington and University of Kansas will run their own suites of instruments. The scientists and engineers will narrate the progress of the mission on several blogs, including one hosted by NASA, and another by Lamont, as well as via twitter.
Wesbite here: http://blogs.ei.columbia.edu/blog/category/ice-bridge/
Bill Illis (19:17:22)
The earth rebounds, when the glacier’s gone. I’ve read that there are areas of the northern US that are still rising.
And I’ve seen it mentioned with respect to Antarctica’s below sea level glaciers.
Should they hypothetically disappear, the rebounding sea floor would even further increase sea levels.
“NASA’s satellite reaches the end of its life this year, and another will not go up until 2015; in the interim, Operation Ice Bridge flights will continue and expand upon the satellite mission. In addition to lasers, the plane will carry penetrating radars to measure snow cover and the thickness of ice to bedrock…”
Now wait a second…
I’m a radar tech, and I know enough to realise that if you point a radar at something, that something heats up. Now point that radar through multiple feet of ice (they did say measurements to bedrock), and ice melts.
Don’t believe me? Put a plate of ice cubes in a microwave, and turn it on.
How much power is that ice penetrating radar putting out, anyway?
Motivations and global warming aside, I envy though scientists and their flights on the DC-8. I miss those bygone days when flying was still an adventure.
Odd that nobody has commented on the obviously faked (well, mislabelled) image of the Larsen Ice-shelf. An ice-shelf is dead flat since it consists of ice floating on the sea. The image on the other hand is obviously of a glacier, not shelf-ice. There are even nunataks (=mountains sticking up through the ice) visible.
This is what shelf-ice looks like from the air:
http://www.gns.cri.nz/iceandsnow/gall_images/gall3/edgeRossIceShelf.jpg
@John Stover
A Giant DC-8 is 157′ X the number of years in journalism school of the observer.
@Dusty
No,no, it’s just headwinds south bound. Wait. Maybe someone is just fractionally challenged.
@Douglas, DC
Fancy flying low-level over the Antarctic in a DC-8? Hope it has been re-engined. Used to be the world’s fastest tricycle.
Pine Island? Didn’t we just discover an active volcano there?
Why no discussion of volcanic temperature/circulation effects on glaciers? If you look at a map of antarctic volcanoes, and a map of glacier alarm, there seems to be an interesting correlation.
Is it just me?
British Government is spending £6,000,000 on TV adds to make people aware of climate change ( eureferendum) glad I am not a British !
From my understanding of the mechanics of a glacier from an engineering standpoint, the “flow” of the tongue of a glacier is more of an extrusion process, than a “flow”, such as the flow of water in a river. The flow of a river is the flow of individual molecules of water, with gravity acting upon each molecule of water in the river, and each molecule flows independently of other molecules.
Inland precipitation (snow) builds up in height in/over a basin, and the snow gets compressed into ice at the bottom of the snow. When sufficient pressure of the buildup of ice occurs, the ice at the bottom is extruded. As the glacier is bound by geological land masses, the extrusion is at the outlet of the basin containing the glacier. Greater pressure from increasing snow/ice levels increases the extrusion process, and increases the rate of movement and furthers the advance of the tongue of the glacier. The rate of the “flow” can not exceed the inland precipitation rate. The addition to the mass of the glacier by precipitation requires more precipitation than the outward “flow” of the ice, as water is always being lost from the surface of the glacier due to sublimation (change of state of the water from solid to vapor without an intermediate liquid state, but with the same removal of heat that is required for both changes of state of the water, i.e., from the solid to liquid, and from liquid to vapor). This removal of ice/snow by sublimation is enhanced by wind, with greater wind velocity over the surface of the glacier increasing the rate of sublimation, and reducing the mass of the glacier.
The rate (in mass) of the flow of ice/snow of a glacier can not exceed the rate of inland precipitation, less water loss due to sublimation. It doesn’t seem to me, an engineer who has done a considerable amount of hydraulic engineering, that reducing the friction at the bottom of a glacier would substantially increase the extrusion process of the ice, as reducing the friction in a channel would increase the flow of liquid water. In any event, the output can’t exceed the input.
For each of some 17 flights, the 157-foot DC-8–too big for runways on Antarctic bases–will make an 11-hour round trip from Punta Arenas, Chile, with two-thirds of each trip spent getting to Antarctica.
Let’s see, 17 X 1/3(11) = 62.3 hrs. over the ice, max. /
Area of PIG:175,000 km² (whole catchment)[1] = 2809 km2 +
and other targets
This is starting to look like an airborne Catlin Expedition. What can possibly go wrong?
Dusty (13:40:36) :
……1,350 miles to the west of PIG, and with a long, large mountain ridge in between, is going to lubricate PIG.
Oh, now I see. It’s just a county fair greased pig contest.
Pardon me, that last paragraph should read “The rate (in mass) of the flow of ice/snow of a glacier can not exceed the rate of inland precipitation, less water loss due to sublimation. It doesn’t seem to me, and engineer who has done a considerable amount of hydraulic engineering, that reducing the friction at the bottom of a glacier would substantially increase the extrusion process of the ice, any more than reducing the friction in the bottom of a basin of water would increase the flow out of the basin through a channel. Reducing the friction in the channel out of a basin of liquid water will increase the velocity of the water in the channel, but will reduce the depth of water in the channel and will not increase the flow in mass of water out of the basin by any substantial amount.
Given all the volcanic and earthquake activity kicking up all over, count me in with “The Volcanoes Did It” group…
Whatever the results, I’m glad they’re at least trying to “bridge” the data gap. The existing satellite might quit soon, and the gap until the next one is frustrating to people trying to study the ice. At least these flights will collect some data during the gap. I am glad that I don’t have to try to convert this data into something comparable to the satellite data for that region.
What will be interesting is whether there is a difference between this data and the satellites. This is using different technologies over much shorter distances. For data which can be compared (the surface layer) the differences will be interesting in several ways. The fact that they’re also able to use instrumentation which a satellite can’t is a bonus, and I hope they learn some interesting things about the geology and ice behavior.
The rate (in mass) of the flow of ice/snow of a glacier can not exceed the rate of inland precipitation, less water loss due to sublimation. It doesn’t seem to me, an engineer who has done a considerable amount of hydraulic engineering, that reducing the friction at the bottom of a glacier would substantially increase the extrusion process of the ice, as reducing the friction in a channel would increase the flow of liquid water. In any event, the output can’t exceed the input.
Based on the following from the Cornell University Department of Geological Sciences it would appear that the outflow can exceed the input.
http://www.geo.cornell.edu/geology/eos/iceflow/model_description.html
tty (23:53:33) :
Odd that nobody has commented on the obviously faked (well, mislabelled) image of the Larsen Ice-shelf. An ice-shelf is dead flat since it consists of ice floating on the sea. The image on the other hand is obviously of a glacier, not shelf-ice. There are even nunataks (=mountains sticking up through the ice) visible.
That looks like one of the glaciers that used to flow into the Larsen before its demise in 2003 (perhaps Hektoria or Green). The caption is fairly accurate, the Larsen has deteriorated, so much so that there’s very little left.
:Henry
Don’t believe me? Put a plate of ice cubes in a microwave, and turn it on.
All that energy in your microwave oven is contained and continuous wave and will heat your ice cubes up very nicely over a minute or so. Don’t try this at home, but if you could open the microwave door, rigging it so that it won’t switch off and point it at your plate of icecubes which you have put 1500feet away [the height that the DC-8 will fly at], then cut the power of the oven to 10% of it’s CW value because these things are pulsed, then open and close the door very quickly because the DC-8 will be flying past at a couple of hundred mph, you will see that the ice cubes will hardly notice the microwave energy and will be far more concerned about being sat outside on a plate in the sunshine!
“In this recent post, we discussed the problems with recent data that showed the argument presented by the EDF’s millionaire lawyer playing clueless environmentalist on Lou Dobbs Tonight that this will be the warmest decade is nonsense. This claim was well refuted and Al Gore’s credibility disassembled by Phelim McAleer, of the new documentary Not Evil, Just Wrong that challenges the lies and exaggerations (totalling 35) in Al Gore scifi horror comedy film, An Inconvenient Truth. 9 were serious enough for a UK judge to require a disclaimer itemizing them be read whenever, the movie was shown in the schools.”
Climate Depot posted my videos of this Lou Dobbs CNN Story.
http://www.climatedepot.com/a/3306/CNNs-Lou-Dobbs-Hosts-Rare-Global-Warming-Debate-Over-Gores-Errors–Mocks-claim-that-capandtrade-is-market-based-plan-Video
I love how WWS doesn’t have a clue what the scientists is talking about and dismisses Dr. Wagner’s statement as if he were some kind of expert.
Just because we don’t understand ALL the minutiae of work doesn’t mean we can’t see where things are headed. You don’t have to understand how your car’s internal combustion engine works to know when you’re driving off a cliff.
I’m sure somebody with no obvious understanding of how stochastic systems function or even basic mathematics or physics for that matter is in a position to lecture us all about what is and isn’t happening to the ice in West Antarctica. I’d be willing to bet WWS has never been to Antarctica. What a true “expert” he is. Please give us more words of wisdom, sir. We’re listening. Tell us how things work in Antarctica.
I’ll give you a direct challenge WWS: Come up with a model using verifiable empirical evidence that says climate change isn’t happening and I’ll give you my life savings. You think you’re so smart WWS? Put your money where your mouth is. If you think scientific research is easy, you show us experts how it’s done. I triple dog dare you.