Archive for July, 2009

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

Rifts / Unconsolidated Ice to Side of Petermann Glacier

Monday, July 27th, 2009

Friday, 24 July 2009

The three images below show rifts and unconsolidated ice to the side of the Petermann Glacier. The images were taken from 3600 feet northwest cliff.
Rifts / Unconsolidated Ice to Side of Petermann Glacier

Rifts / Unconsolidated Ice to Side of Petermann Glacier

Rifts / Unconsolidated Ice to Side of Petermann Glacier

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Jason E. Box
guest scientist aboard
Greenpeace Arctic Sunrise

Extreme Ice Survey in far north western Greenland at 81 deg. N at Petermann Glacier

Monday, July 20th, 2009

19 July 2009, Sunday

With the assistance of the Greenpeace crew and donors, the Greenpeace ship Arctic Sunrise, and the Greenpeace helicopter, five time lapse [Extreme Ice Survey] cameras, are now ‘watching’ the Petermann glacier floating ice shelf. Petermann is one of the widest outlets to the vast Greenland inland ice sheet. Each minute, we get high resolution pictures from a variety of points of view from high cliffs 2500-3600 feet [760 -1090] meter above the enormous 10 mile [16 kilometer] wide ice shelf. The views are surreal, the scale deceiving. The clear dry air and absence of artificial objects such as roads or buildings makes distances the matter of speculation. It’s only after imagining an Empire State Building into your view that you realize, we are three times above its height. Mind your step!

We’re interested in this site because Petermann has lost 150 square kilometer of ice area in the past 10 years. Cracks have formed and widened in the lower half of the 1500 square kilometer [580 square mile] floating glacier. A crack nearest the end of the fjord suggests that a 100+ square kilometer [39+ square mile] area of floating ice may detach as a 5 billion ton ice island this summer melt season. That area is larger than Manhattan Island.

Greenpeace would like to use this event to raise urgency of ongoing Arctic climate warming, glacier loss, and accelerating global sea level rise, to urge policy makers at the global climate negotiations this December in Copenhagen.

Since installation 28 June 2009, the Extreme Ice Survey cameras have captured the progressive disintegration of two Manhattan Islands size segments of sea ice, more specifically, the loss of 3.8 square kilometers [1.5 square miles] of ice. At one minute intervals, the action is very dramatic. We will be posting a video soon. Stay tuned! We expect much more breakup in the coming two weeks.

Dr. Jason E. Box installing EIS cameras beside a 1090 meter cliff overlooking Petermann Glacier

Dr. Jason E. Box, Byrd Polar Research Center and the Ohio State University, installing EIS cameras beside a 1090 meter [3600 foot ] cliff overlooking Petermann Glacier, far northwest Greenland.

EIS cameras seen from the air as viewing a growing crack atop ridge at Petermann Glacier

EIS cameras seen from the air as viewing a growing crack atop a 760 meter [2500 foot] ridge at Petermann Glacier, far northwest Greenland.

EIS cameras viewing the front of Petermann Glacier

EIS cameras viewing the front of Petermann Glacier, far northwest Greenland. The darker colored ice in the foreground is thin sea ice; the lighter, glacier ice. The distance across the fjord is 16 kilometers [10 miles]. The cliff on the opposite side is 1090 meter [3600 feet] high; two additional EIS cameras have been installed there. All the glacier ice in this frame is expected to detach this summer.

note: Higher resolution versions of these images will be available in future; the cost of transmission large amount of data from the Greenpeace Arctic Sunrise via satellite link is an unnecessary  expense.

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Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise

The Telegraph.co.uk Photograph Gallery of Greenpeace Greenland Petermann Glacier Survey

Saturday, July 18th, 2009

Saturday, 18 July 2009

Jason forwarded an email reporting that Greenpeace International are very pleased that the UK newspaper The Daily Telegraph have posted a gallery of 27 photography, by Nick Cobbing, of the Arctic Sunrise’s Petermann Glacier survey on its website. The photographic gallery is available via the following link:  Telegraph.co.uk Photograph Gallery

The ‘date stamps’ within the file names indicate the images were captured over the period from 29 June to 16 July 2009.

The forward email noted: This is significant because The Daily Telegraph is regarded as the UK politically conservative ‘newspaper of record’.  On the day of its initial hosting, the article was at the top, front, center of the homepage.  Greenpeace in Greenland

Person show in the photographs [mentioned in the dispatch] includes, in order of appearance
-  Dr. Jason Box, glaciologist [from the Byrd Polar Research Center and The OSU]
-  Dr. Alan Hubbard, glaciologist from University Of Wales, Aberystwyth
-  Eric Philips, polar explorer and expert in glacier travel
-  Texas Constantine, Canadian radio operator
-  Eric Philips
-  Dr. Richard Bates, Geophysicist of the Scottish Oceans Institute at the University of St. Andrews,
-  Arne Sorensen, ice pilot

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Jack R. Box, Salem, Ore., for
Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise

Kennedy Channel CTD Castings

Saturday, July 18th, 2009

18 July 2009, Saturday

A group of us are doing 4 hour shifts during a ~24 hour set of sea soundings of Conductivity-Temperature-Depth-Current [CTD+C] casting every 2 km across the 38 km Kennedy Channel, the narrowest part of Nares Straits.

Depths have been 150-400 m.

The weather has been quite fair. We joke about pulling up a halibut or a mermaid from the bottom.

Views on either side of the fjord are inspiring; 6400′ mountains on Ellesmere Island to the west.

Red mountains of Ellesmere Land, western Kennedy Channel
Red mountains of Ellesmere Land, western Kennedy Channel

Freshened waters are found in the upper 10-20 meters. We find a cold current at depths from below the surface layer to ~180 meters flowing southward. Below that is a relatively warm current with a complex direction pattern, with a northward component. Right at the bottom of the channel is a cold salty ‘deep water’ signature.

There is very little sea ice, just a sparse collection of small ragged shaped bergy bits floating down the strait ahead of the Arctic Ocean pack ice.

It is quite the task to keep the boat from drifting southward.

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Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise

While in the Nares Straits

Friday, July 17th, 2009

Wednesday 15 July 2009

While in the Nares Straits, we have been busy getting what we can done [lots!] on Petermann. We are now departing south to avoid Arctic Ocean pack ice.

The ice is FINALLY drifting south through Nares Straits. This year has been exceptional because the sea ice has not consolidating in Nares Straits [between Greenland and Ellesmere Isand, Arctic Canada], but, rather, has formed an “ice arch” at the north end of Nares in the Lincoln Sea. We are avoiding getting trapped by the ice floes and having a delayed exit from the region by early August. We will seek shelter in the lee of Franklin Isand or further south in Wright Bay in northeastern Kane Basin.

While in Kane Basin, we’ll conduct oceanographic surveys and get some glaciology going on Humboldt, the northern hemisphere’s widest [100 km] glacier.

Morale on the ship has been high … we have been moored beside the Petermann Glacier front with main engines off [quiet] and the weather has been spectacular. Air temperatures have not been below 4 C [38 F] and have been as high as 14 C [58 F]. The clear skies and constant sun make it feel warm. I am wearing tee-shirts and shorts right now. I have not worn my hard shell pants, only my stretch guide pants. So, NOT SO COLD!

Temperatures have climbed steadily while here, melt intensity climbing, numerous waterfalls visible cascading far from the fjord walls.

Nares Straits Fjord Waterfall

I am meeting with a Chinese journalist on board; we will discuss the state of knowledge of Greenland’s cryosphere. Last night, I played table tennis with Alun [Welsh], Eric [Australian] the Zephan [Chinese].

We had an early morning helicopter flight to check the working of a GPS and a time lapse camera, install an iceberg tracker, and recover a temporary time lapse camera.

We saw multiple pods of narwhals today on our flight ‘home’ to the ship. They were feeding in silty water which apparently containing some source of food.

Nares Straits Narwhals

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Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise

Fishing For Data

Friday, July 10th, 2009

Yesterday was and today will be another day of dipping ocean sensors in cracks through the Petermann ice shelf into the ocean. We are learning about ocean currents, temperatures, and salinities; all these are important for understanding ice melt at the ice-ocean interface.

Prior work using satellite remote sensing has shown that Petermann melts much more from its floating base than from the surface. We’re finding cracks and holes all over the ice shelf surface with which to map the sub-glacial oceanography.

Sounding Crack in Petermann Glacier

Whirlpool on Petermann Glacier_July 2009

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Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise

Petermann Glacier Polar Bear Family

Friday, July 10th, 2009

July 09, 2009

The other night, Greenpeace Arctic Sunrise crew members, on the bridge, reported sighting a polar bear family cruising across the Petermann ice shelf.

Theses are the photographs I got with a 70 mm lens.

polar bear family cruising across Petermann ice shelf

polar bear family cruising across Petermann ice shelf

We were safely aboard ship.

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Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise

Greenpeace Ship Arctic Sunrise Has Arrived Petermann Glacier Front – Cameras Deployed

Wednesday, July 8th, 2009

Wednesday – 08 July 2009

The Greenpeace ship Arctic Sunrise arrived the Petermann Glacier front [81 deg. 10 min N, 61 deg. 55 min W] in a rush against time to install sensors before the detachment of a 5 billion ton [13 x 8 kilometer] ice island.

Now, we await that action and hope it happens [if it must] while we are on  site.  We can remain until early August, at the latest, if need be.

We have been busy with on-glacier GPS and radar measurements and oceanographic measurements in cracks on the ice shelf.

I have installed 6 time lapse cameras; four on cliffs over-looking the ice shelf and two on the ice looking at cracks.

Also, see:

Greenpeace weblog
http://weblog.greenpeace.org/climate

Google Map:
http://tinyurl.com/arcticmap

Campaign website:
http://www.greenpeace.org/arctic

Photos:
http://www.flickr.com/photos/greenpeaceinternational/sets/72157620765994686/

Telephone:  Iridium telephone
Primary:     +881 677 701 408
Secondary: +881 641 423 871; answers only on bridge
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Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise

Petermann Glacier’s Trimlines Indicate ~270 Meter [885 foot] Thickness Change Since Circa 1865

Wednesday, July 8th, 2009

Wednesday – 08 July 2009

Trimlines are the “bathtub rings” left by glaciers retreating.  For many glaciers, the maximum observed thickness relates to the Little Ice Age,  circa year 1865.

The trimlines are often visible as horizontal changes in rock color or arrangement. Areas of distinct changes in vegetation (lichens, mosses) typically demarcate trim lines.

At Petermann Glacier, trimlines were identified as under-cut gravel [talus aprons from rockfall] roughly 30 meters above the current ice surface level. Given that the lower Petermann Glacier is floating, a 30 meter change in freeboard indicates a ~270 meter [885 foot] change in thickness since circa 1865.

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Jason E. Box
Byrd Polar Research Center
guest scientist on Greenpeace ship Arctic Sunrise