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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Kaboom says:
July 13, 2013 at 10:00 am
I thought Rhode Islands is an area measurement for ranches and farms in Australia.
No Rhode Islands are a type of friendly chicken.
Kon Dealer says:
July 13, 2013 at 11:00 am
Glacier calving- another alarmist wet dream.
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And those who cant think for themselves will buy it…
Increased Ice over water… Normal bending due to wave action… Breaks off and whala… Ice burg..
Commonsense would tell you that you just fell in the water and wake up from the stupor..
When glaciers calve, alarmist have a cow. That explains all the bellowing.
“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.”
Astounding! Computer modelers speaking the language of empirical science. I wish them the greatest success in their endeavor. When and if they have the empirical generalizations (not theoretical generalizations) that capture the calving process then they can use them to explain and predict events of calving. Climate science will become an empirical science some day.
Somebody is cherry picking units. If that calf were properly measured using fractal math it would be larger around than the east coast of America is long. Being that large just how many Hiroshima units would be required to melt it? That is important because that is how much the ocean heat will be reduced by the action of melting that bad boy. That heat will have to be backed out of all future alarmist calculations of pending death as it is “soft heat”, not real heat. God does not take from the global warming budget that heat lost to glacial melt.
In a perfect world where floating glacial snouts were not so easily victimized by greedy capitalists, how long would it take before the Antarctic ice extent grew such that you could walk to Tristan da Cunha from Sao Paulo, Chili, and what would the coastal perimeter of Tuvalu be (using proper fractal measure and not that old-world bogus average that is so often used) were the sea level reduced to a more normal and desirable level consistent with a world free of calving ice sheets?
I hope I’ve not left out any contemporary CAGW hyperbole.
Ice-bergs calving is a natural process.
But natural processes are interesting. Please don’t disparage a researcher who is curious about the event.
Ice grows over the sea and breaks off; that is a good starting point. But what else is there about the process to learn?
If it just shears as a 30 mile crystal then that is remarkable. If it fractures in disparate places then where and why?
This is real science. Catastrophic Anthropogenic Global Warming has nothing to do with it. Not physically or philosophically is it cAGW.
But it is cool (ahem).
‘Glacier in Antarctica does what glaciers do.’
AGU, Richard Alley how ice shelves in the Antarctic act as a flying buttress to glaciers!
Gunga Din, that was absolutely perfect!
Edit: “From NASA, who has moved up” Which, not who. Agency, not person.
Calving: if an ice sheet is growing, what else could it do when it extends too far over water, but calve? No tree grows to the sky, no ice sheet grows to the equator. At the moment.
Patrick says: July 13, 2013 at 10:14 am
“Kaboom says: July 13, 2013 at 10:00 am”
No! That’s New South Wales, it’s bigger than Texas!
That’s what they say about Alaska, too, but nobody really believes it.
They should drag that iceberg up into Galveston Bay where it could do some good. Might have enough melted off by the time it got here that it would fit.
With the Wilkins ice shelf collapse, it was apparent that a several week ocean swell crunched the shelf, then pulled the pieces out to sea when it retreated. Here’s the sea level during the collapse at Rothera, the nearest tide gauge to Wilkins.
http://www.rockyhigh66.org/stuff/rothera_antarctica_tide.png
There is an unusual amount of methane being released this year from the central part of Antarctica that started around February. I don’t know what to make of it.
(Not sure about quality of data)
http://methane-hydrates.blogspot.com/2013/06/high-daily-peak-methane-readings-continue-over-antarctica.html
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An Alaskan once said that if Texans didn’t stop bragging about how big it was they’d split Alaska in two then Texas would only be the third largest state.
All explained in one of Capt. W E Johns’ Biggles stories that I re-read recently after +/- 55 years.
Mind you, Johns also has polar bears in the Antarctic, so maybe he’s about as reliable as a climate scientist.
Fwiw – another area conversion: “as big as Texas” = 2.5 times smaller than Queensland.
Here is what is going on behind the doors . . not quite science now is it / / NAS funding Grant science for the EPA – http://www.foxnews.com/politics/2011/12/19/epa-ponders-expanded-regulatory-power-in-name-sustainable-development/#ixzz2Y0trUcTA
About 12 million sq km of Antarctic sea ice melts each year between the southern hemisphere winter maximum and the summer minimum. Now we have a ”280-square-mile ice island” projecting over the sea and calving; 280 sq miles is 725.2 square kms so this represents about 60 millionths of the annual summer antarctic melt – just to put it in perspective. Wow: we are all doomed /sarc.
And the mean sea level charts continue to show steady, constant, MSL rise no with acceleration, denoting a steady constant run-off from the land-based ice sheets.
While it is of course of interest to know the mechanics of the calving process, I would have thought glacier flow mechanics are more important – once out over the ocean I would think the calving process is essentially just a form of cantilever calculation, as to the off-shore range at which the up and down bending moment of the ocean tides causes the ice to fracture.
This is a non-story, simply intended to frighten the natives.
Bob Tisdale says:
July 13, 2013 at 8:40 am
Hmm. Isn’t Houston, TX or Harris County, TX the size of Rhode Island? That would mean the iceberg is still smaller than a US city?!
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The first article I read was “Chicago” size:
http://www.csmonitor.com/Science/2013/0712/Iceberg-Antarctica-loses-Chicago-sized-chunk-of-ice
Michael D Smith says:
“The physics behind the calving process are highly complex”
Translation: We have no idea what we are talking about.
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The more likely translation:
With man made global warming, we are likely to see more ice sheet calving like this
“The physics behind the calving process are highly complex”
Translation: We haven’t been able to fit to a global warming model yet.
I can see the problem, make more icee, more icee break off. Make less Icee, less icee break off.
Question: How many scientists does it take to fit a square peg into a round hole?
Answer: As many as you will fund! Perhaps more!
JudyW says:
There is an unusual amount of methane being released this year from the central part of Antarctica that started around February. I don’t know what to make of it.
It’s all the cows, silly. Do try to keep up.
There has been a theory about methane – hydrates [frozen methane] mass melting creating huge areas of high gas bubble concentrations which reduces the ability of the ship/boat to remain afloat. Who knows.
My most recent comment disappeared. Maybe the problem was on my end. Closed the browser before hitting “Post Comment” or something like like that. But if I crossed a line, please let me know what it was. All I did was ask if it about time for another post about “weather cows”.
Sorry. Now the the comment is there.
No clue what happened.
Carry on.
Sorry, the area in question was the Bermuda triangle.
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Gas bubbles in water will reduce buoyancy. Sort of the opposite effect salt in the Great Salt Lake or the Dead Sea.
Hmmm… Cows don’t just…vent…methane but what they deposit produces can produce methane.
Bubbles will increase the volume of water if not it’s density.
Maybe all the CAGW BS is responsible for sea level rise?