The largest ice shelf on the Antarctic Penninsula is disintegrating further by calving a huge iceburg. The dimensions of the iceburg are about 25 mi. by 1.5 mi. (41 kilometers by 2.5 kilometers).

Source

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A thin strip of ice, just 6 kilometres wide, is all that is holding back the collapse of a huge ice shelf in Antarctica, according to glaciologists.

The Wilkins ice shelf � previously some 16,000 square kilometres in area � has been disintegrating fast. On 28 February, an iceberg 41 km long and 2.5 km wide broke off the ice shelf. This triggered the runaway disintegration of a further 570 square kilometres of ice.

"I would be very surprised if it survives more than a couple more melt seasons," says Ted Scambos of the University of Colorado, US.

Other researchers, including David Vaughan of the British Antarctic Survey, believe it could be gone within weeks. "The ice shelf is hanging by a thread � we'll know in the next few days or weeks what its fate will be," he says.

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You can read more about it here.

Video of the ice shelf.

EDIT: I have replaced my original overlay with a series of four overlays provided by NASA Earth Observatory. The series shows how dramatic the breakup has been. Thanks for the link blt and for the suggestion mspelto

Thanks Hill
Just read about this on the BBC
http://news.bbc.co.uk/2/hi/science/nature/7313264.stm

Alas, we can sit and watch our planet fall apart on GE!

Here is a report of earlier stages of the break-up in 1998.

Great job with the Overlay. Those things are tough at such an extreme latitude. It's curious that this event hasn't been added to the National Ice Center's Antarctic Iceberg Tracking Webpage yet. It seems to me that this should qualify as the biggest Quadrant 'A' iceberg to date.

Here is a composite of that image and a higher resolution closeup. Both are slightly more accurately positioned. Enjoy

A bit more of the story on the Wilkins breakup from the BAS

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Glaciologist Ted Scambos from the University of Colorado alerted colleagues Professor David Vaughan and Andrew Fleming of the British Antarctic Survey (BAS) that the ice shelf looked at risk. After checking daily satellite pictures, BAS sent a Twin Otter aircraft on a reconnaissance mission to check out the extent of the breakout.

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This is what they saw

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"I've never seen anything like this before � it was awesome. We flew along the main crack and observed the sheer scale of movement from the breakage. Big hefty chunks of ice, the size of small houses, look as though they've been thrown around like rubble � it's like an explosion."

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Hi Res- Wilikins Breaking Up
Hi Res- Wilkins from Twin Otter

The scene was also photographed by Taiwan�s Formosat-2 satellite.

Hi Res - Wilkins from Formosat 2

And for a bonus, while I was looking for these, pics I noticed that the NASA Earth Observatory is way ahead of us. Check out the attached KMZ file from NASA. KMZ file of the ice shelf disintegrating suitable for use with Google Earth showing the collapse using 4 dated A 250-meter-resolution overlays.

Charcot island and Latady Island are key pinning points for the ice shelf on its west facing front. As you can imagine a large floating shelf of ice is not as stable without such bedrock pinning points either on the lateral margin or beneath the ice sheet. As the ice shelf thins do to melting, its contact with the pinning points weakens, this enables calving, which further weakens the connection at the pinning points. This ice shelf is 6 degrees south of the Larsen B Ice Shelf and much more in line with the latitude of other large ice shelves of the main Antatrctic Ice Sheet, it is also quite close to Pine Island and Thwaites glacier which have also experienced greater retreat, and faster flow of late. The demise of the ice sheet was predicted long ago by the British Antarctic Survey because of its tenusous connection with the pinning points. The open water black right to the ice shelf front is not a good sign for the iceshelf either. I would suggest that one of the two original posts with kml files be updated to include a path of the ice front for both moments in time.

Thanks to all who have provided additional material and links. Lately I have read in several sources that the break-up may have stopped for this year as Austral Winter approaches and freezing superceeds melting. But whether this is the case or not, it seems likely that the break-up will continue, if not now, then next summer. I've edited the initial post to include a NASA Earth Observatory folder which includes overlays detailing the break-up.

CNN report on the biological changes brought about by disappearance of ice shelves.

blt's file with time stamps for animation

file corrected to give equal time to each frame

The thing that amazed me about this and the Larson B iceshelf break up of a couple of years ago is the speed at which it happened. It's like throwing a rock at a piece of glass. They both just shattered. What's next? The Ronne or Ross Sea Ice shelfs? If so, its Katy bar the door. No such thing as global warming? Indeed. Doubters and those that attempt to forestall meaningful action on the problem should hang their heads in shame. Their actions place the planet and humanity at grave risk.