Operation IceBridge Alaska Spring Campaign 2018

I've been getting really slack about posting, so here is an effort to start catching up. Below is an assortment of pictures taken during the Alaska OIB campaign in May 2018. During these campaigns we fly a lidar (laser scanner) over repeat profiles to document glacier change over large parts of Alaska. We also use a radar to measure ice thickness. This year we had an additional instrument: a snowdepth radar from the University of Kansas.

Below are some impressions from the flights:

Hubbard Glacier continues its advance. This glacier has been threatening to close off an entire part of a fjord, but so far strong tidal currents have kept this gap open, after it briefly closed in 2002, causing an enormous outburst flood when the resulting moraine dam broke. The glacier advances and retreats seasonally, but didn't come close to closing this spring.

West side of the advancing Hubbard Glacier front

This is the gap at Gilbert Point, where the two parts of the fjord (Disenchantment Bay and Russell Fjord) meet. It has closed temporally in 1986 and 2002, but the 2002 outburst flood removed a lot of sediment and tidal currents have managed to keep a gap open.

The Klutlan Glacier surge

Several surges have taken place in the Wrangell/St. Elias in the past few years, but most of them are done now. The one exception is the Klutlan Glacier, which is still going strong.

This is the lower part of the Klutlan. The ice in the foreground is surging, but the glacier continues many kilometers into very stagnant ice. The background covers a vast area of debris covered ice with trees and vegetation on it. It will be interesting to see if the surge reaches that area.

Mt. Steele: A large rock/ice fall broke away from this mountain several years ago and covers a large area of the Steele Glacier

Stranded ice that resulted from ice draw down in the upper areas of the Steele Glacier

The big ones: Mt.Logan (left) and Mt. St.Elias (right)

The Stairway ice fall on the Root Glacier is one of the largest ice falls in the world (~1500 m). At the bottom of it, it forms these beautiful wave ogives. Each crest is separated by one year of ice flow.

Operation IceBridge Fall campaign

I'm being increasingly lazy about keeping this field blog up to date, but since it is complete over the past few years, I am going to update it. Better late than never!

In the second half of August we flew the Operation IceBridge Alaska mission. This is a NASA sponsored mission with the primary goal of measuring elevation change of many glaciers all over Alaska. I am doing radar surveys to try to measure the location of the bottom of the glacier.

These missions always result in lots of waiting for suitable weather, interrupted by long days when conditions are good. But this August we had a particular sustained stretch of very windy conditions, and we ended up not being able to fly our primary targets. We still got some work done. Below are some impressions.

Unfortunately I had my ISO set to something ridiculously high, which is why this picture appears so grainy. But it is amazing nonetheless: The surging Walsh Glacier destabilized a slope and this led to a clear fracture through a rock glacier, exposing an entire cross section. It nicely shows that much of the inside of a rock glacier actually consists of ice. I think it's even more than what appears here, because debris would have quickly covered some of the ice.

Beautiful fall colors

Kennicott Glacier has been retreating and creating this proglacial lake that rapidly increases in size

The surging Klutlan Glacier

Back in Greenland

I had an opportunity to join a team of scientists from the UK's Scott Polar Institute at Store Glacier in western Greenland. This is one of the big outlet glaciers of Greenland,  but contrary to many other glaciers in the area, the front has been relatively stable over the past decades. I went there to set up a terrestrial radar interferometer, which is an amazing instrument that can measure ice velocity at very high resolution (every 3 minutes in this case).

Travel to the field site was interesting because Air Greenland had many weather delays, so I arrived in the town of Uummannaq with a 3-day delay. To get to Uummannaq is complicated: From Kangerlussuaq you travel via Ilulissat and then Qaarsut on small airplanes (Dash 8) and then with a helicopter for the last bit, because there is not really sufficient space for an air strip at Uummannaq. I spent two unplanned nights in Ilulissat, which was nice, since I had spent a lot of time there, but not in the past 5 years. It is amazing to see how many tourists there are now. 

I ended up spending only four days in the field to set up the instrument and train the team how to use it. Below are some impressions from the trip.

Ilullissat: The city of ice bergs

The ice fjord outside Ilulissat

A snow fall in July, which is very unusual, contributed to several days of delay

Icebergs in the midnight sun

Uummannaq Island with the town (on the left flatter side)

The Uummannaq harbor with the big rock behind it

An interesting iceberg near the Uummannaq harbor

The terrestrial radar interferometer set up by Store Glacier

The Ilulissat icefjord on the way home

Nice evening light near Kangerlussuaq

Operation IceBridge Spring campaign

For the past several years I joined the Operation IceBridge Alaska campaign. The primary goal for this NASA funded work is to measure glacier change with an airborne lidar. We also try to measure ice thickness with a radar, which is a tricky proposition, because the radar signals bounce of all the mountains and obscure the returns from the glacier bed.
Flying in the mountain always requires a lot of patience to wait for good weather. This spring was particularly windy and we could not fly for almost two weeks, because conditions were never quite right. But finally we completed a survey of Glacier Bay (I wasn't there for that), the Sargent and Harding Icefield, and the Eastern Alaska Range. Below are just a few impressions:

The calving front of Chenega Glacier in Prince William Sound with a small calving event caught in the act

Excelsior Glacier is a rapidly retreating outlet of the Sargent Icefield, calving big icebergs into a proglacial lake

Beautiful internal waves

Root and Kennicott Glacier with Mt. Blackburn

The Tana Glacier is also retreating rapidly with a proglacial lake that is getting bigger each year

How deep is the Bagley Icevalley?

We have been trying to measure the depth of the Bagley Ice Valley for years, using airborne radar. But it has been an enigma; we suspected because of its depth. Temperate ice (ice at its freezing point) contains water and that makes it really difficult for radar waves to penetrate. We had a chance to do a survey on the ground with a very low frequency system and it looks like this was successful. We are still working on the data, but it looks like we've found ice that is more than 1500 m thick.

Deployment by Ultima Thule's Single Otter

The front half of the radar setup with antenna and a sled containing the receiver

How far is it to bedrock? Photo: Jack Holt

Pulling the radar across the glacier. Michael on the snowmachine and I'm being pulled on skis. Photo: J. Holt

Black Rapids Glacier

Every year in spring we make a trip to Black Rapids to do some mass balance measurements. Once again we found a beautiful day for it, and this time my daughter Sonja got to join me as well.

Surprisingly, Black Rapids Glacier had quite a low snow year; it was one of the thinnest snow covers we've measured in several decades. It's surprising, because Fairbanks had quite a nice year. In general, Black Rapids Glacier continues to thin rapidly.

Glacier caves

I've been slacking with this blog. Here is a picture from a visit to Juneau during spring break. We got an opportunity to visit the glacier caves at Mendenhall Glacier. Amazing!