Friday, March 29, 2013

The Wrangell-St.Elias Mountains

Yesterday we had one of these rare days with clear weather along Alaska's coastal mountains. We took advantage of it with a long day of surveying. This gave us a chance to see some of the most spectacular mountain landscapes on this planet.

First we flew Yahtse Glacier in Icy Bay. Icy Bay is an incredible place. The mountains rise straight out of the sea up to the towering 5,400 m high Mt. St. Elias.
Wind scouring patterns on Yahtse Glacier

Upper Yahtse Glacier

Looking down the steep terminus of Yahtse Glacier

Icy Bay

Yahtse Glacier, one of Alaska's few advancing glaciers
Icy Bay

After Icy Bay we headed south-east along the coast across the vast expanse of Malaspina Glacier.

Next was Yakutat Glacier, a place we had studied extensively during the past few years as part of an NSF funded project. Yakutat Glacier is one of the most rapidly retreating glaciers in Alaska. It calves into a lake and has lost several kilometers of its frontal area in just a few years. The glacier front is hard to recognize compared to just two years ago.

The front of the West Branch

Crevasse patterns on the West Branch
The East Branch still has some floating ice, but it is rapidly breaking apart

Next up was the Hubbard Glacier, North America's longest tidewater glacier

Hubbard Glacier is healthily advancing. Twice already it has pinched off Russell Fjord at this location. In the back is Turner Glacier, Alaska's only surging tidewater glacier. It is surging again, for the third time in just ten years

The tide is moving glacial silty water into Russell Fjord

Some impressions from the upper Hubbard Glacier

Is Logan Glacier surging?

Three days ago we surveyed the Logan Glacier, which flows from Mt. Logan (North America's second highest mountain and Canada's highest) into the Chitina Valley. During the survey we saw signs of a surge. This glacier is not known to surge, but some unmistakable signs include very active shear margins and crevassing, and a bulge that is expected to travel down glacier over the coming months.
Shear margin with active crevasses
Ice bulge with lots of new crevasses
Paul enlists Chris' help to check the engine on his plance

A draining glacier lake left this pattern as the ice collapsed

Airborne radar

 This week we are based at Ultima Thule Lodge, from where we conduct airborne radio echo sounding measurements to find out how deep the glaciers and ice fields are. The lodge is located in the middle of the Wrangell-St.Elias National Park and provides easy access to some of the biggest glaciers and ice fields outside the polar regions.

 The lodge is located in the Chitina valley, an expansive valley with steep side walls and many water falls that form spectacular ice falls in the winter.


The valley is also a favorite place for sheep and goats. Can you spot the one behind the ice pillar?