Study Tracks Dinwoody Glacier's Retreat
The Journey In
It’s a hard 23 mile hike into the Wind River Range to one of the state’s largest glaciers. It’s called Dinwoody, and every step is a study in the powerful impact this glacier has had on these mountains in the last 1.5 million years.
“This particular valley is actually really cool because you can see essentially vertical cliffs all the way down,” says University of Wyoming hydrologist Elizabeth Traver. She’s our guide, and this is her second year partnering with the Interdisciplinary Climate Change Expeditionor ICCE. “There’s no question where the glacier went and how it scoured out the sides of the mountain.”
Her job up here is to teach students how to measure just how much water is melting off the glacier. And it’s melting fast. In the last 50 years, about 34 percent of Dinwoody Glacier has washed away.
Under a hot afternoon sun, all that glacial melt really rages, making creek crossings with heavy packs downright dangerous. Over the roar of the stream, Traver hollers instructions.
“If we want to do this truly safely, one person on this side should take off a pack so if someone falls in, you have a pack off, you can catch them!”
Day three, we round a corner and there’s Dinwoody, a glacially slow moving river of ice.
“If you look at it,” Traver says, “you can actually see a current in it.”
It flows off the flank of Wyoming’s highest mountain, Gannett Peak. Wyoming has the largest concentrations of glaciers in the Rocky Mountains: 38 named glaciers, and 25 are in the Wind River Range. As it flows down, the glacier heaves up giant boulders as if bulldozed. Tucked among these boulders, we find a makeshift glacier research station where 13 students and three professors are hard at work on several scientific studies to track the glacier’s retreat.
“Unquestionably, this area is changing and it’s changing with haste,” says CWC environmental health instructor Jacki Klancher. She’s the leader of this expedition. Wiry and energetic, she’s passionate about this glacier. She gestures dramatically up at the splashes of black dirt and rock fallen onto the glacier’s fringe.
Credit: Jordan Wirfs-Brock
“This finger is new to us this year, that dirt stream there is new to us. And that is new to us,” she says pointing to another large blotch of soil on the white glacier. She says as the ice melts, debris above sloughs off. And all that dirt speeds up melting because its dark color attracts heat.
“It’s on its way to becoming essentially a rock glacier,” Klancher says. “Any layperson could come up here three years in a row and be stunned each year by the dramatic transformation.”
Flecks Of Carbon
But it’s not just all that dirt that’s heating it up.
One of Klancher’s former students, geography major Lane Tomme, takes me down into the glacier’s moat. It’s sort of like a castle’s, but as Tomme explained, “It’s basically a glacier that’s connected to a rock and since this rock is so hot, it just melts away this separate area and creates this ditch-like area.”
It’s a ditch about three stories deep, and right now we’re at the bottom of it. Today, Tomme is ice climbing up the wall of the moat to collect snow samples. He’s looking for black carbon, microscopic flecks of exhaust from cars and factories that drift here from around the world. He says, on days like this, the sun shines on the glacier and the black carbon heats up faster than dirt.
“Those little black specks heat up and accelerate the melting process of the glacier,” Tomme says. “And that’s why it’s really important to figure out where all this is coming from.”
And that’s exactly what he’s hoping these samples will tell him.
Measuring The Melt
After he's done, we slip and slide off the glacier to its toe. Here, melted ice filled with fine ground rock, called glacial flour, turns the water a milky turquoise. The creek is narrow here, a good spot for hydrology students to get a reading of just how much water is melting off the glacier. One of those students is CWC outdoor education sophomore Grace Hartman.
“We want to have a benchmark so we can measure next year’s as climate change increases temperatures and increases the melting of the glaciers.”
Hartman takes notes while another student stands in rubber waders in the middle of the icy creek with a flow meter.
“It's a metal rod and has a sensor on the end where it can measure the velocity of the water.”
Hartman says, the Dinwoody Glacier provides a steady, predictable source of water for ranchers in the Wind River Valley below, including the reservation.
“The past few years, we’ve had some patterns of increased temperatures,” Hartman says. “Normally, in the spring we have an increased flow of water and right now the peak is getting sooner, therefore less water will flow at the end of the summer. And a lot of ranchers and farmers in Wyoming actually rely on this particular Dinwoody Glacier.”
Length, Height and Width
In a way the glacier is a frozen reservoir, supplying ranchers with water for crops and livestock year round. But right now, that reservoir is deflating like a balloon and the ICCE project found a way to track that loss of volume. Using pack horses, they actually hauled a large piece of equipment called a ground penetrating radar up here.
“It’s at least 50 or 60 pounds, just on its own without even including the batteries and other wires,” said UW geology sophomore Ian McGlynn. “So it’s a pain in the butt to get up here.”
The GPR can measure the thickness of the ice by locating exactly where the bedrock is underneath.
University of North Dakota student Lance DiAngeli is doing his thesis on the glacier. “Now we have length, height and width so that way we can get a total volume of the glacier and see how that's really changed.”
In Wyoming, people are starting to worry that climate change will someday deplete the amount of water that goes to irrigators downstream. But ICCE’s project leader Jacki Klancher says, it goes way beyond Wyoming. She says, sitting on the Continental Divide, Dinwoody Glacier is the headwaters of the Missouri River.
“This is not Fremont County’s water, this is not Wind River Indian Reservation water, this is not Wyoming water,” she said. “This is the nation’s water.”
I think of that as I scoop up a water bottle full of melting glacier and drink deep.
The ICCE Project is also documenting new discoveries about year round prehistoric villages in the Dinwoody Glacier area. Melodie Edwards will bring you that story September 23 on Open Spaces.
The ICCE Project builds on the 2007 thesis work of Kyle Cheesbrough at the University of Wyoming.