processing the backlog of Petermann Glacier photos

I take advantage of the delay time here in Uummannaq to process a backlog of last year’s photos of Petermann Glacier that I shot during last year’s campaign. With a very nice camera/lens on loan from James Balog, I pressed the button to shoot more than 20,000 photos. I believe I have enough photos to publish a comprehensive illustrated assessment of this place…

http://dl.dropbox.com/u/3783460/PT/20090715_105002_Petermann_Glacier__Copyright_Jason_Box_sm.jpg

July 2009. The endless summer days at 81 degrees north latitude produce substantial summer melting. While summer melting is not necessarily abnormal, melt intensity is expected to continue to increase as the global climate system responds to continued atmospheric loading of heat trapping gasses.

http://dl.dropbox.com/u/3783460/PT/20090711_115123_Petermann_Glacier__Copyright_Jason_Box_sm.jpg

The Petermann Glacier medial river barely trickles out to sea. It’s not a stronger flow because it’s intercepted about 20 km upstream (in the distance) where the river pours into a breach in the surface called a moulin.

http://dl.dropbox.com/u/3783460/PT/20090711_115356_Petermann_Glacier__Copyright_Jason_Box_sm.jpg

The shearing of the ice along the fjord walls occurs too quickly for the ice to deform. The shearing strength of the ice shelf is exceeded and rifts form as the ice tears apart. This is a normal process. The rifts are, of course, weak areas on the ice shelf. Petermann ice shelf has detached a large area along recently along one of these rifts. Melt water filling the rifts weakens the bonds, literally forcing apart the rift bottom.