Athabasca drilling: 50 years later

 In the 1960s one of my glaciological heroes, Charlie Raymond, did his PhD work on Athabasca Glacier in Jasper National Park. He figured out how the motion at the base of the glacier is distributed. This is now textbook material. We were interested in finding out how this has changed in the meantime. The glacier is now 50 m thinner, so it is basically a different glacier in the same setting. We spent most of the month of July drilling 12 holes to the bottom of the glacier and putting instruments in the holes to measure the deformation of the ice and the water pressure and electric conductivity at the bottom of the hole.

View of the Athabasca Glacier as it flows down from the Columbia Icefield

The hotwater drill set up. We heat up this water and then pump it into a hose to melt holes through about 200 m of ice.

Most of the material was flown up with helicopters, but we did have to haul up a spare heater. I put the picture in black and white, because it reminded me a bit of the methods of the Scott expedition.

Lots of melting and supraglacial rivers that eventually disappear into moulins

In addition to the borehole work we also put up several GPS stations to measure the flow of the ice

This glacier is a bit of a crazy place. Due to the proximity of the Icefield Parkway, it is amongst the world's most visited glaciers. One way to get on the glacier is on these big tired glacier buses (one of which is used by the US program in Antarctica) to drive right up on the ice.

David is checking on his borehole instruments

We also set up a radar to measure glacier velocities

Alaska Airlines flight seeing

 Every once in a while you get one of these amazing blue sky days in Southeast Alaska. That's when a routine commute turns into amazing flight seeing, and it pays off to consistently book window seats! These pictures are from a flight from Juneau to Anchorage and then back to Fairbanks.

Glacier Bay. The Tlingit name is Sit' Eeti Gheeyi (Bay in the place of glaciers).

Yakutat Glacier. We had a project there a few years ago when all that lake was still covered with ice.

West branch of Yakutat Glacier that has now separated from its tributary. Our models indicate that this glacier will entirely disappear during this century, even without any further warming.

Looking up Russell Fjord to Hubbard Glacier. The huge Mt. Logan is in the background left.

Close-up of the advancing Sit' Tlein (Hubbard) and Sit' Kusa (Turner). The Sit' Kusa enters from the left and is known for its regular and vigorous glacier surges.

The Sit' Tlein (Malaspina) with Malaspina Lake. It looks like the lake has been getting bigger since last year.

Looking across the Sit' Tlein into the tributary Seward Glacier (on the right) and Agassiz Glacier (on the left).

Lig̲aasi Áa (Icy Bay) with Yas'eit'aa Shaa (Mt. St. Elias). The Tyndall Glacier descends from the mountain at over 5,400 m down to Taan Fjord.

Lig̲aasi Áa (Icy Bay)

A look over the Bagley Icevalley, which is over 1400 m deep. In the background are the Wrangell mountains.

Denali (the Great One) is peaking out of the clouds. To its left is Sultana (The Wife, Mt. Foraker). I think Begguya (The Child, Mt. Hunter) is just peaking out between the two.

IGS meeting on Maritime Glaciers: Excursion to Tracy Arm

 We had a nice meeting of the International Glaciological Society in Juneau. This was my first in-person meeting since the start of the pandemic. It was so good to see old friends and make new connections. During the week, we had a beautiful excursion to Tracy Arm, just South of Juneau. I had not been there since 1996. What an amazing place.

A Black Bear feeding on barnacles. It's amazing how they navigate the steep fjord walls.

The South Sawyer Glacier, which has retreated significantly since I visited it in 1996.

The Sawyer Glacier. It has almost retreated out of the ocean.

This side of the glacier is grounded on a gravel bar now. The gravel provides sufficient resistance for form this beautiful fold in the ice.

A Steller  Sea Lion colony ..

... and a beautiful sunset, probably with some help from the forest fires in the interior.

Finally again: The 2022 McCarthy International Summer School in Glaciology

 After a 4-year covid-induced hiatus we were finally able to hold the summer school in glaciology again. I really love participating in this event and, once again, we had a fantastic group of students, spending 10 days in one of the most picturesque places in Alaska. Below are some pictures.

Students are busily solving Continuum Mechanics problems.

Ice cave by Donoghue Lake

Root Glacier with the magnificent Stairway Icefall

Margin (or terminus?) of the Root Glacier as it joins the Kennicott Glacier

Proglacial Lake at the East side of the Kennicott Glacier

The Ruth Glacier gorge

This post is more than a year late, because National Geographic was going to do a story on it, but they just cancelled it ...

We were invited to go up to the Ruth Glacier near Denali to do some ice thickness measurements. This place if of interest, because it is suspected to be one of the deepest gorges in North America. The glacier is flanked by Mt. Dickey on one side and Mooses Tooth on the other side, both of which rise over 1500 m (5000 ft) above the glacier surface. Because so much ice is funneled through this gorge it was also suspected to be quite deep and there is a report from seismic measurements that claims that the ice is over 1000 m deep. 

The area is often visited by climbers. It was also of great interest to Brad Washburn, as, for example, shown in the recent movie 'The Sanctity of Space'.

Here is a look up the gorge, with Mt. Dickey on the left:

The upper glacier (the Amphitheater) contains a large nunatak where the famous Talkeetna pilot built a mountain hut for use by climbers and skiers, or people who just want to spend some time in an amazing setting. 

 

This nunatak became a private inholding in Denali National Park which allowed the younger Sheldon to build a luxury lodge in an unbelievable setting. We were invited to use this lodge as a 'base camp' for a week, from where we went out to survey the glacier.

A sunrise photo of the majestic Denali towering more than 4000 m above us:

Our goal was to measure ice thickness, which we did with a specially designed low frequency radar. This was quite successful in the amphitheater where we measured ice up to about 900 m (3000 ft) thick, but the Great Gorge alluded us, probably because of the deep and narrow geometry. However, we can be pretty certain that the depth is less than a 1000 m, simply on consideration of ice flow.

A particularly nice sun rise with a sun dog:

We had mixed weather, but on snowy days we got to see some amazing snow avalanches coming off the steep valley walls.