Greenland glacier calves island 4 times the size of Manhattan, UD scientist reports it last happened at this scale in 1962. Must have been climate change back then too. Watch the media now as this story is only about an hour old. BTW it fractured, not melted, and in case some people forget: glaciers calve to the sea there, it is what they do. – Anthony
1:40 p.m., Aug. 6, 2010—-A University of Delaware researcher reports that an “ice island” four times the size of Manhattan has calved from Greenland’s Petermann Glacier. The last time the Arctic lost such a large chunk of ice was in 1962.
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Here is a NASA Image of the day from August 30th, 2007 – Anthony:
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“In the early morning hours of August 5, 2010, an ice island four times the size of Manhattan was born in northern Greenland,” said Andreas Muenchow, associate professor of physical ocean science and engineering at the University of Delaware’s College of Earth, Ocean, and Environment. Muenchow’s research in Nares Strait, between Greenland and Canada, is supported by the National Science Foundation (NSF).
Satellite imagery of this remote area at 81 degrees N latitude and 61 degrees W longitude, about 620 miles [1,000 km] south of the North Pole, reveals that Petermann Glacier lost about one-quarter of its 43-mile long [70 km] floating ice-shelf.
Trudy Wohlleben of the Canadian Ice Service discovered the ice island within hours after NASA’s MODIS-Aqua satellite took the data on Aug. 5, at 8:40 UTC (4:40 EDT), Muenchow said. These raw data were downloaded, processed, and analyzed at the University of Delaware in near real-time as part of Muenchow’s NSF research. Petermann Glacier, the parent of the new ice island, is one of the two largest remaining glaciers in Greenland that terminate in floating shelves.
The glacier connects the great Greenland ice sheet directly with the ocean. The new ice island has an area of at least 100 square miles and a thickness up to half the height of the Empire State Building. “The freshwater stored in this ice island could keep the Delaware or Hudson rivers flowing for more than two years. It could also keep all U.S. public tap water flowing for 120 days,” Muenchow said.
The island will enter Nares Strait, a deep waterway between northern Greenland and Canada where, since 2003, a University of Delaware ocean and ice observing array has been maintained by Muenchow with collaborators in Oregon (Prof. Kelly Falkner), British Columbia (Prof. Humfrey Melling), and England (Prof. Helen Johnson). “In Nares Strait, the ice island will encounter real islands that are all much smaller in size,” Muenchow said. “The newly born ice-island may become land-fast, block the channel, or it may break into smaller pieces as it is propelled south by the prevailing ocean currents. From there, it will likely follow along the coasts of Baffin Island and Labrador, to reach the Atlantic within the next two years.”
The last time such a massive ice island formed was in 1962 when Ward Hunt Ice Shelf calved a 230 square-mile island, smaller pieces of which became lodged between real islands inside Nares Strait. Petermann Glacier spawned smaller ice islands in 2001 (34 square miles) and 2008 (10 square miles). In 2005, the Ayles Ice Shelf disintegrated and became an ice island (34 square miles) about 60 miles to the west of Petermann Fjord.
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UPDATE: At 2:15 PM I added an Aqua sat image (source here) in visible light with rotation to North and annotation at the head of this article. – Anthony
Happened in 1912 too. Or was that a rogue iceberg from the antartic?
Wow… and it did that during summer, when ice melts? Amazing!
Here’s the Aqua image the article makes reference to (about half way into the image using IE8 H/V slider bars;
http://rapidfire.sci.gsfc.nasa.gov/realtime/single.php?2010217/crefl2_143.A2010217084000-2010217084500.250m.jpg
OMG!!! GLACIERS ARE BEHAVING ABSOLUTELY NORMALLY!!! IT IS MUCH WORSE THAN WE THOUGHT!!!!
Massive chunk of ice breaks off Greenland glacier
http://voices.washingtonpost.com/capitalweathergang/2010/08/massive_iceberg_breaks_off_gre.html
“Icebergs calving off of Greenland’s glaciers are nothing new. In fact, the Canadian Ice Service and the U.S. Coast Guard’s International Ice Patrol estimate that anywhere between 10,000 and 40,000 icebergs calve from the glaciers of western Greenland in a given year.”
“What is unusual, however, is the size of this new iceberg, which is more typical of Antarctic than Arctic waters.”
Her you can see daily ice-floe updates from DMI
http://ocean.dmi.dk/arctic/kennedy.php
Best
Santa
They actually pre-empted the calving. When looking for more news on it, one of the first hits is from the LA times in 2008.
stevengoddard says:
August 6, 2010 at 12:24 pm
Temperature anomalies in Greenland over the last 30 days, showing usually cold temperatures over the ice sheet.
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Obviously the temperatures over Greenland’s Interior are of little interest during the melt season.
I’ve yet yo see a melt pond within Greenland’s interior.
Your video does show (I believem since no scale is shown for the green/yellow colors) positive temperature anomalies where historically melt ponds have always occured, along Greenland’s perimeter.
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stevengoddard says:
August 6, 2010 at 12:32 pm
Temperatures at the top of the Greenland ice sheet have averaged 10F during July and August. The warmest temperature this summer was 27F. The coldest was -16F on July 13.
http://www.wunderground.com/history/station/04416/2010/7/1/MonthlyHistory.html
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Now see that wasn’t so hard, showing significantly positive temperature values on Greenland’s perimeter (the top of Greenland no less) where all the melting action actually occurs.
“Does that mean that only a handful of glaciers remain in Greenland that terminate in floating shelves? Did a lot of glaciers like that melt into oblivion already?”
Yes and no. Actually there is not that many outlet glaciers that reach the sea in Greenland. Along much of the periphery the ice melts in place on land. That there are so relatively few large tidewater glaciers also means that the remaining ones are often quite large, since they each drain a large area of the icecap. I suppose it is possible that some small tidewater glacier on Greenland has retreated onto land recently. I know that this has happened in Svalbard and Alaska.
“So, this is actually sea ice that just broke away from the land, really. This ten mile long chunk was already thirty plus miles out to sea.”
Shelf ice from a glacier is floating in the sea, but it is not sea ice in the normal sense. It is vastly thicker and accumulated on land rather than being frozen seawater.
Looks like this may turn into another recycled ice shelf story every summer.
http://voices.washingtonpost.com/capitalweathergang/2010/08/massive_iceberg_breaks_off_gre.html
Glacier death spiral, obviously…..
Well the Washington Post has a story on line about it, but doesn’t come straight out and claim AGW as the cause. They skate around that with links to RealClimate to learn why glaciers retreat:
And if you click on the RealClimate link you come to an article linked to a bunch of papers but something real interesting:
So it took 2 years for the thing to finally break off? However of course RC says that it’s all due to “Climate Change”
Then at the end of the arcticle by the WAPO they make a reference to another article that deals with glacier melt and sea level rise (they also provide a link). Thus giving an inference that this big piece of ice will contribute to that. I wonder why they didn’t come straight out and say it will? Maybe because if anyone read through the entire RC piece on that glacier you would find that the area broken off was already floating in the water like an ice cube:
Matter of fact the article has a nice picture of the crevasse which they describe is more like a rift as seen by satellite
You can read the WAPO piece here: http://voices.washingtonpost.com/capitalweathergang/2010/08/massive_iceberg_breaks_off_gre.html
The RC part here:
http://www.realclimate.org/index.php/archives/2008/10/what-links-the-retreat-of-jakobshavn-isbrae-wilkins-ice-shelf-and-the-petermann-glacier/
I wonder if some other MSM outlet is going to try the melt leading to sea level rise angle and if RC is going to make that article on its site disappear.
If this plugs the Nares strait, it’ll stay plugged for a very long time. That might matter; the ice lost through the Nares was all multi-year.
Good news. This island will float off south and, as it is so big, won’t melt. It will therefore increase the Sea Ice extent. 🙂
That huge ice island is probably going to get stuck by the sea-ice and in return re-uniting with the glacier again in the following winter months.
Glacier calving is a sign of anything but a receding melting glacier and ice shelf. Unless global warming is to blame for growing as well as melting glaciers and ice shelves. The media is indeed recycling these scare stories. Kinda reminds me of Oregon State football back in the day. Every year the papers would brag up the team. Same sentence structure. Same paragraphs. Same number of words. But the names were changed. And every year the Beavs ended up vying for the Toilet Bowl against the Ducks. Belief trumps data.
Oh no! How come they used to farm on Greenland? What was the calving like then? :o)
http://www.greenland-guide.gl/leif2000/history.htm
“…the rate of warming in 1920–1930 was about 50% higher than that in 1995–2005.”
http://www.agu.org/pubs/crossref/2006/2006GL026510.shtml
So does this mean Arctic sea ice just increased? Are sea ice and glacial ice “fungible”?
The front fell off the glacier… reminds me an Aussie sketch:
I must say this strikes me as the greatest death threat today apart from a walk by the waterway where geese mommas hiss at you as you walk past their chicks.
The ice is not “lost” as the article claims. It is still there and not likely to go anywhere any time soon. Usual BS.
“The last time the Arctic lost such a large chunk of ice was in 1962.”
Lost? It’s not lost. I see it… right there in the photo.
wcp says…
Maybe I’m wrong, but I think that calving is usually a sign of glacier growth in situations like this – it gets too big, and a chunk breaks off…
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You know, I’ve never actually thought about that, and I think you might be right! Anthony? Steve? Do you agree with wcp’s conclusions? They seem quite solid to me.
CRS, Dr.P.H. says:
August 6, 2010 at 1:28 pm
Glacier death spiral, obviously…..
Nope, sorry, its a Rotten Glacier… 🙂
if you compare the 2007 photo with the current image, you can see that the glacier still ends at roughly the same spot.
it has advanced, which is consistent with the glacier gaining mass in the accretion zone.
seems like a considerable advance in just 3 years, the icecap must be gaining mass much more rapidy than previously thought!