First Petermann Ice Island photos

REMEMBER: There are two days left to vote on the poll widgets in the right hand bar, one is for Cryosphere Today minimum daily sea ice area, the other for NSIDC minimum September/monthly sea ice extent. You can also re-vote if you like by going to the polls directly (here for NSIDC minimum monthly SIE, and here for CT minimum daily SIA). More info and all the numbers for minimums in the 2005-2011 period in this blog post.

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Dr. Andreas Münchow, sea-going physical oceanographer, has been in the Nares Strait area for the past couple of weeks to retrieve moorings chock-full of data, deploy new ones and do all kinds of other exciting science stuff. He is currently in Resolute where the internet connection has allowed him to upload some photos to his blog, photos of the mega-iceberg that recently calved off of Petermann Glacier. I gratefully reproduce the photos here, for more info go to Dr. Münchow's blog, Icy Seas:

Petermann Ice Island 2012 (PII-2012) as seen Aug.-11, 2012 at the entrance of Petermann Fjord. The view is to the north-west. [Photo Credit: CCGS Henry Larsen.]

North-eastern portion of Petermann Glacier on Aug.-11, 2012, the meandering river is the centerline, view is almost due east. [Photo Credit: Canadian Coast Guard Ship Henry Larsen.]

Awe-some...

Comments

[fredt34]

Is there an approximation for the free board / heigth above the water? I mean, we have this "Manhattan size" comparison: how high would be the Empire State building or other famous skyscrapers compared to this "piece of ice"?

[Seke Rob]

If was almost shocked in awe to read that the 'fjord' (if you can call it that), is in places 1200 meter deep. If that were by glacial erosion, and the 90% rule is applied, the head of the glacier could be that much high. Not so, per this piece:
http://glacierchange.wordpress.com/2010/03/27/petermann-glacier/

The slow velocity results in a greater duration of surface and basal melting, which effectively thins the glacier to a mere 60-70 meters at the calving front. Petermann Glacier loses 90% of its thickness before it reaches the calving front thinning from 600-700 m at the grounding line primarilly due to basal melting.

[rayduray]

NASA's Earth Observatory has a surface air temperature map for July. The area of the Petermann Glacier appears to have been about 4 C. above average for the month:

http://earthobservatory.nasa.gov/IOTD/view.php?id=78869

See also this page for an animated long term temperature anomaly map:

http://earthobservatory.nasa.gov/Features/WorldOfChange/decadaltemp.php

[Twemoran]

Pii2012 is on the move since the 13th after grounding in Kane Basin. The tides are still getting higher and will peak on the 18th so other grounded ice may still move out this season. (think south of Flade Isblink)

Arctic.io's Split Zoom is up (Torsen's working on making it more robust) and is the easiest way to follow small changes in the ice.

Terry

[Mike Constable]

I was wondering how the rate of movement down Nares Strait of Pii2012 compares with that of the larger island that calved a couple of years back? (whether the thickness [freeboard/draft] of the berg makes a difference to the speed southwards, is it thicker because it was calved further up the fiord?).

Where has/will it get grounded to slow its progress, will fast-ice trap it for the winter? Will it affect the flow of ice through Nares by influencing the formation of ice-bridges in the area?

I was watching it on arctic.io but of course that goes blank at this season in that area. Has anyone managed to put a tracking beacon on it like they did to part of the Ayles shelf after that broke up?

Lots of thoughts - any answers (or interest?)

[Twemoran]

Mike

Pii2012 has broken into a couple of pieces with the largest having grounded on the Kane Basin sill.
There are beacons, but rather than regurgitating everything here let me direct you to Andreas Munchow's blog where all will be made clear.

http://icyseas.org/2012/10/22/petermann-and-ryder-glacier-ice-island/

BTW if you haven't read any of his articles yet, you're in for a treat.

Terry

[Andreas Muenchow]

Just added a new perspective as I just learnt how to access NASA's IceBridge data which includes laser altimeter and ice-penetrating radars that scan the underbelly of both Greenland's and Antarctica's ice-sheets, glaciers, ice-shelves, and much more. Happy times ...