Posts Tagged ‘David Decker’

Humboldt Ice Islands

Wednesday, July 29th, 2009

28 July 2009, Thursday

I just returned from an attempt flight to Petermann glacier. Clouds did not permit us to access Petermann. The clouds’ silver lining was being able to shoot photos of Humboldt Glacier in not the usual harsh light. There is a lot of science content in the story behind the images. We’re making GPS, ocean, and satellite image measurements to help tell that story credibly. Anyway, here’s a teaser…

Humboldt glacier has been retreating since at least 1992. Area change since year 2000 is 175 square kilometers. Today, flying over, I was astonished by the number of large [> 1 kilometer] tabular ice bergs.

Humboldt glacier ice islands let out to sea, freed by sea ice disintegration July 2009.

Humboldt glacier ice islands let out to sea, freed by sea ice disintegration July 2009.

Area change measurements by David Decker at Byrd Polar Research Center indicate a net loss of 25 square kilometers since the end of summer 2008. Most of the area change has been in the arcing ‘calving bay’ seen below.

Looking south southeast 3000 feet over the Humboldt glacier calving bay.

Looking south southeast 3000 feet over the Humboldt glacier calving bay.

Melt water communicating with the glacier bed has created large areas of sediment rich waters bubbling up at the calf ice-free Humboldt glacier front. The dark area at the lower right of the image above is the window frame of the helicopter.

The northern limit of Humboldt glacier seen from the west, looking east 4600 feet above the sea.
The northern limit of Humboldt glacier seen from the west, looking east 4600 feet above the sea.

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Jason E. Box
guest scientist
Greenpeace Arctic Sunrise