From NASA, who has moved up from “Manhattans” to quarter states as a scale comparison unit:
Antarctic Glacier Calves Iceberg One-Fourth Size of Rhode Island
This week a European Earth-observing satellite confirmed that a large iceberg broke off of Pine Island Glacier, one of Antarctica’s largest and fastest moving ice streams.
The rift that led to the new iceberg was discovered in October 2011 during NASA’s Operation IceBridge flights over the continent. The rift soon became the focus of international scientific attention. Seeing the rift grow and eventually form a 280-square-mile ice island gave researchers an opportunity to gather data that promises to improve our understanding of how glaciers calve.
“Calving is a hot topic in cryospheric research. The physics behind the calving process are highly complex,” said Michael Studinger, IceBridge project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md.
Although calving events like this are a regular and important part of an ice sheet’s life cycle—Pine Island Glacier previously spawned large icebergs in 2001 and 2007—they often raise questions about how ice sheet flow is changing and what the future might hold. Computer models are one of the methods researchers use to project future ice sheet changes, but calving is a complicated process that is not well represented in continent-scale models.
Days after spotting the rift, IceBridge researchers flew a survey along 18 miles of the crack to measure its width and depth and collect other data such as ice shelf thickness. “It was a great opportunity to fly a suite of instruments you can’t use from space and gather high-resolution data on the rift,” said Studinger.
Soon after, researchers at the German Aerospace Center, or DLR, started keeping a close eye on the crack from space with their TerraSAR-X satellite. Because TerraSAR-X uses a radar instrument it is able to make observations even during the dark winter months and through clouds. “Since October 2011, the evolution of the Pine Island Glacier terminus area has been monitored more intensively,” said Dana Floricioiu, a DLR research scientist, Oberpfaffenhofen, Germany.
When IceBridge scientists returned to Pine Island Glacier in October of 2012, the rift had widened and was joined by a second crack first spotted that May. The close-up data gathered by the instruments aboard NASA’s DC-8 gave a view of the ice that added to TerraSAR-X observations. “It’s a perspective I hadn’t had before,” said Joseph MacGregor, a glaciologist at the Institute for Geophysics at The University of Texas at Austin, one of IceBridge’s partnering organizations. “Before, I was always looking nearly straight down.”
In the time since discovering the rift scientists have been gathering data on how changes in the environment might affect calving rates. For ocean-terminating glaciers like Pine Island Glacier the calving process takes place in a floating ice shelf where stresses like wind and ocean currents cause icebergs to break off. By gathering data on changes to ocean temperature and increasing surface melt rates, researchers are working toward implementing the physics of calving—a calving law—in computer simulations.
The data collected since 2011 is one step in building an understanding of calving and further research and cooperation is needed to understand not only calving but how Antarctica’s ice sheets and glaciers will change in the future. The unique combination of airborne and orbiting instruments that closely watched this recent calving event was the result of a spontaneous collaboration between researchers in the field. “It was at the level of colleagues coming together,” said Studinger. “It was a really nice collaboration.”
For more information on Operation Ice Bridge, visit:
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I think it was back in the early 80’s but some silly bugger in Australia came up with the idea of towing ice bergs from Antarctica to Australia to use as a water source. It was another period when our dams were slowly drying up.
Silly Southern California even designed diesel motors to mount on the ice berg to bring fresh water to Los Angles . . silly humans
Thanks, Anthony.
What is a glacier advancing on the sea to do?
Keep on growing till it covers the whole ocean?
No, it calves. The resulting icebergs eventually melt and ocean level goes down.
Regarding methane levels, just search “AIRS Methane” on youtube and watch the variability that occurs. Yes, lots of methane comes off of Antarctica.
I’m with Dodgy Geezer: why isn’t this already a well-known phenomenon? Let me say a kind word about models–physical models. What would be lacking in a simulation of this type of event in a refrigerated wave tank that would require studying an actual glacier? There could be an informative answer, but I just don’t see it now.
Bruce Cobb says:
It’s all the cows, silly. Do try to keep up.
Perfect timing: cows, calving. I get it. The Ralph Cicerone studies always brings out the funny in science. Argentina needs to reduce the amount of grain to the cows if there is that much methane reaching Antarctica.
Here’s what everyone in the USA should learn from this: compared to real States, Rhode Island is a tiny little thing that is massively over-represented in the Federal Government which has helped turn it into a liberal cesspool.
Here’s an idea, let’s glue together Rhode Island, Massachusetts, Connecticut, Vermont and New Hampshire into one, still tiny, leftist super State ( and they can have NYC if they want it ). That would change 10 Senators into 2, better matching the ratio in the rest of the country. What to do with Hawaii though.
Wikipedia :: Rhode Island and other troublesome little leftist enclaves
Kaboom says:
July 13, 2013 at 10:00 am
I thought Rhode Islands is an area measurement for ranches and farms in Australia.
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Actually we tend to measure farms and stations (ranches) by the number of things per square metre that can kill you..
It is still a somewhat large number.
This is just a sample.
http://www.cracked.com/funny-163-australia/
The engineering of glacier calving (extending as cantilevered tablet until failure) is easy, but it’s difficult for climate scientists because they have to do it with a CO2NTROL KNOB and the GCMs. Willis can probably reduce the problem to two linear variables for them.
About 10 years ago, such iceberg breaks were being shown as big news, reason to enact Kyoto. Doesn’t seem to be happening now. I remember at the time, even scientists like Prof Prynn at MIT didn’t mention how this sort of thing is routine, when someone said they thought it would be the basis for getting the public to do something about global warming.
In January 2008 the British Antarctic Survey (BAS) scientists, Hugh Corr and David Vaughan, reported that 2,200 years ago a volcano erupted under the Antarctic ice sheet. This was the biggest Antarctic eruption in the last 10,000 years. The volcano is situated in the Hudson Mountains, close to Pine Island Glacier.[16][17] The eruption spread a layer of volcanic ash (or tephra) over the surface of the ice sheet. This ash was then buried under the snow and ice. Corr and Vaughan were able to map this ash layer using an airborne radar system and calculate the date of the eruption from the depth of burial of the ash. This method uses dates calculated from nearby ice cores.[17] The presence of the volcano raises the possibility that volcanic activity could have contributed, or may contribute in the future, to increases in the flow of the glacier.[18]
The ash being buried by snow is misleading, as it will be exposed during the austral summer resulting in increased albedo driven melt.
Well I prefer the Delaware unit myself; well I think so; izzat the Veep’s State; the second smallest state in the United States.
The North South extent od Delaware, is easy to remember, it’s the distance from Downtown Anchorage to Wassila, where Former Governor Palin lives.
And you can place the state of Delaware, in 12 different non overlapping places, in the Arctic National Wildlife refuge.
Mike N, you are so right. A 150 km block of sea ice broke off after a collision. It was not global warming but was a regular natural event. But the break away did not create a shipping hazard. My cousin went to Antarctica many years ago hired by a British university. Came home convinced that the summer break away of ice was the creation of global warming. Sent me photographs of a bay somewhere with a few ice bergs, not huge ones, floating around. There are warm water streams under the ice. A wonderful doco showed coral, orange, pink and purple under the ice cap in areas. I couldn’t believe it until I saw a large seal looking at the camera man under the water, very tame too. The warm streams probably are created by underground volcanic thermal vents. I wish I could remember who organized this docomentary, he is a famous documentary producer. I’ll Google and find out.
Werner Hertzog, in ‘Encounters at the End of the World’ got a Oscar nomination. It’s wonderful I recommend you view it sometime.
Gunga Din says:
July 13, 2013 at 2:33 pm
Sorry. Now the the comment is there.
No clue what happened.
Carry on.
=================
When you hit one out of the park, as you did earlier.
It leaves us expecting more of the same 🙂
“NASA, who has moved up from “Manhattans” to quarter states as a scale comparison unit”
So do those convert to centiQueenslands or deciQueenslands?
TELL EGYPT!
They can send a boat to hook on to the giant ice berg and tow it to Egypt to supplement the irrigation waters of the Nile. (Or sell chunks as ice cubes for drinks)
This is not the shape of the iceberg! This is a cropped picture of the glacier itself. Why would this ambiguous picture even be used? Here is a picture – scroll down.
http://www.guardian.co.uk/environment/2013/jul/10/iceberg-antarctic-pine-island-glacier
In the real picture, the iceberg, though large, looks puny so they went for the cropped glacier shot.
From the Guardian article in previous comment
“Andy Smith of the British Antarctic Survey said: “Although there’s nothing to suggest this event is unusual, it’s not to say that it’s not interesting. We are extremely interested because we want to understand if the loss of a large block of ice has an affect on the flow of the glacier”.
http://en.wikipedia.org/wiki/Pine_Island_Glacier”
They needs to hire a junior engineer to answer such simple questions before they broadcast their stupidity. Here is the answer to the effect a “large block of ice” calving has on the flow of the glacier itself:
http://en.wikipedia.org/wiki/Pine_Island_Glacier”
“10 percent of the West Antarctic Ice Sheet, drains out to the sea via Pine Island Glacier,”
This and the Thwaites glacier drain 175,000sqkm of the West Antarctica ice sheet. Andy, the flow isn’t going to be affected by the calving (100% confidence). There is no resistance to the tongue of ice pushing out over the sea to hold this mighty glacier back. There is likely even a temporary lifting of the weight of the glacier at the hinge as the tongue is bouyed by the water so that it would slow down a miniscule amount when the ice cracked and broke off. Ya know, all these researchers and NGOs are really on safari.
Why do they want to learn more about how glaciers calve? Simple, they want to know how they can spin that into something catastrophic to get more Government grants. They also want to tie it into CO2 emissions. They already have the end result, they just have to figure how they got there. Hansen’s sea level rise is a function of CO2 emissions despite that having nothing to do with the effect. What they can’t prove they ‘ll make up.