Monday, August 01, 2011

Measuring and melting glaciers in Alaska

I've been offline the last two weeks to do a volunteer vacation/vacation in Alaska. As Stoat has mentioned somewhere, volunteering is a great way to ignore your air travel emissions, and this was the third time I've done it by taking GPS measurements of glaciers.

The photo above isn't photoshopped, btw, nor is it my natural complexion. The electric blue lighting inside glacial ice has to be seen to be believed. That photo wasn't inside the glacier we measured though, but a glacial iceberg we recreated in, near Valdez in an outfall lake. As you can see from the photo after the jump, we wouldn't be able to get inside the glacier we measured except by unfortunate accident. Since my niece accompanied me this time, I was somewhat determined to make sure that wouldn't happen.

So this is the glacier we measured, a source glacier for the Teklanika River in Denali National Park. The snow bank at bottom left hangs off the terminus, despite all the rock debris. It continues all the way to the ridgeline horizon, although the bedrock outcrops in the middle show the glacier's about ready to melt down into two smaller glaciers. Only the widest connection is glacial ice, I think, the rest just looks like snow bands.

We walked up to the cirque you can barely see just below that connection, taking measurements along the way. Half of that cirque and almost all of the rest of the bottom glacier has already lost its snow cover, before July. This bottom glacier is doomed. Still, it's helpful to get ground measurements, and walking a centerline like we did might get the actual researchers a little closer to mass measurements. You have to backpack to get to these glaciers, so we vactioneers can save some time for the researchers.

I was a little disappointed not to measure other glaciers, but a sow grizzly and two cubs were in the way on the previous day. I argued to my family team that we could get around them, but apparently I was unpersuasive (and this was before the unfortunate mauling in Yellowstone).

Great vacation otherwise - I used to work in Alaska, and I love getting back. A boat trip from Valdez by the Stan Stephens tour was slightly marred by a captain who pointed out two glaciers that haven't retreated while failing to mention the retreat that's happening generally. One of them was a tidewater glacier, a type that goes through cycles mostly unrelated to climate.

All else was fine, though, and I just need to get caught up.