By Chris Case
For years, scientists have been studying and reporting on the accelerating rates of retreat of the world’s ice sheets (the largest glaciers), the decline of mountain glaciers big and small, and the subsequent rise in sea levels. Media reports have followed: retreating glaciers around the world (at the poles, in the Alps, closer to home in Glacier National Park); polar bears that are quickly losing their habitat; island nations that are seeking to buy property elsewhere, fearing their land may soon be underwater. It all might seem a little foreign, a little too distant to have a profound impact. But, if you need a small reminder of how things are changing ever closer to home, look no further than Colorado’s Front Range. The range boasts all of the 14 named glaciers in the state, most of them in Rocky Mountain National Park. They’re all very small—and getting smaller.
As any good scientist would tell you, shrinking glaciers in the Front Range of Colorado do not equal an indicator of global change in our climate—it just isn’t that simple.
But studies have shown that since 1999, most of the glaciers in the Front Range have shown marked recession. All of this climate science has become controversial—because it’s become politicized. That’s too bad, because glaciers are an incredible species. They are worth visiting, if for no other reason than to witness history. And whether humans are at fault for an environment significantly and irreversibly altered by our activity doesn’t really matter in this context. The climate is changing; the glaciers are shrinking, with indisputable evidence to prove both. What may matter to you is that Colorado’s mountains may someday soon be void of its glaciers and the 135 other recognized permanent snow and ice patches. You love Colorado’s mountains because of the trees, flowers, wildlife, lakes, streams, and perennial snow patches that coat them. In no small part, you can blame the glaciers and snow for the aesthetic of our state. “Glaciers are a manifestation of the seasonal snow that we depend on for water resources: water quantity and water quality,” says Mark Williams, a geographer with the Institute of Arctic and Alpine Research (INSTAAR) at the University of Colorado. “Snow and ice-melt provide water when we need it most, during the summer growing season.” But, does Colorado have any real glaciers?
The basic definition of a glacier is an accumulation of ice that has formed from falling snow, one that’s thick enough to deform under its own weight. In other words, the ice moves. Snow cornices and snowfields can slip as a mass and exhibit movement, but are not actually deforming. So, yes, we have glaciers. You may also hear the term glacieret, something perhaps more familiar to scientists in Colorado than to anyone else, anywhere else.
“A glacieret is just a term for a very small glacier,” says Matt Hoffman, a geologist at Portland State University with an extensive knowledge of Colorado’s glaciers. “Using that term keeps the glaciologists working on ice sheets and in places like Alaska from saying things like ‘Colorado? There aren’t any real glaciers there!’” So, yes, we have glacierets, too. But if you’re walking through the mountains of Colorado and come across snow or ice, it may not be so easy to tell what you’re looking at. To see glaciers as their denuded selves, without the cover of snow, there is a fairly narrow window. “To the untrained eye, you would just look for massive ice, as opposed to snow, but it will probably only be exposed in late summer—August or September—but before fall snow begins,” Hoffman says.
Earlier this decade, two discoveries in the Front Range led to a startling suggestion. On two separate instances, hikers stumbled upon what were later learned to be remnants of bison horn—radiocarbon dated at 2,090 and 2,280 years old—released from perennial snow patches as they slowly receded. The suggestion? Ice and snow coverage along the Continental Divide, where the discoveries took place, have retreated to levels not seen in two millennia—since the time of Christ, or the beginnings of the Roman Empire. Glaciers in Colorado may form a little differently than in other places—most of them are found in cirques where wind and avalanche can deposit snow—but they still operate like any other glacier. They’re churning through the snow that enters them—at a place scientists call the bergschrund—and spitting it out at its leading edge every 200 to 300 years. But more interesting may be what’s permanent. “Permanent snow and ice patches are different [from glaciers] in that they are static features,” says Craig Lee, an archaeologist at INSTAAR. Unlike the snow in glaciers, the permanent snow can be thousands of years old. “I use glaciers as a proxy—their footprint might stay the same but the thickness of the glacier may have lessened—so I know that if runoff is greater, that ice patches near it are melting and might be revealing things that are older than what’s in the glaciers. I know that if something is found, that it has been revealed recently because things that are that old [3,000 years old] don’t last that long in the open air, on the ground.” But don’t think that you can be the next Indiana Jones of glacial archaeology.
“Bison horns and skulls are found because they stand out,” Lee says. “Mule deer, elk, bird remains, other paleontological findings are out there… But any findings are protected by law, and you should contact land managers or archaeologists with any findings.”
It wasn’t until late in the nineteenth century that the presence of glaciers in Colorado, past or present, was recognized. Clarence King, the first director of the United States Geological Survey, classified the state as having been formerly glaciated, but neither he nor Ferdinand Hayden identified any glaciers in Colorado in their now famous United Survey of the American West. The first scientific description of a glacier in Colorado belongs to G.S. Stone of Colorado Springs, who described Hallett Glacier (now known as Rowe Glacier) in northern Rocky Mountain National Park in the journal Science in 1887. N ear the turn of the twentieth century, discoveries flourished. Tyndall Glacier had been identified in 1893 by Frederick H. Chapin and Sprague Glacier in 1895 by Enos Mills. W.T. Lee first described Arapaho Glacier (Colorado’s largest) in 1900 in Science. Mills wrote a guidebook in 1905 that included a map locating Andrews, Hallett, Sprague, and Tyndall Glaciers. Isabelle Glacier was discovered by Fred A. Fair in 1908. So, after only 100 years of knowing that glaciers exist in this state, are we close to losing these glaciers altogether?
“Based on my research, you might estimate anywhere from 15 to 50 years before these glaciers disappear,” Hoffman says. “However, these glaciers exist in highly favorable locations where they get up to 10 times the local snowfall due to wind-drift and avalanching, and they are shaded from summer sun. I expect that as they get smaller, many will become increasingly resilient to additional retreat. That being said, sustained regional warming would have the potential to eliminate or severely reduce many of these glaciers and perennial snowfields.”
When they’ll disappear calls for much speculation, though what will happen when glaciers are gone is generally recognizable. “We’ll lose diversity in the plant and animal species, and insect species,” says Lee. “More and more, we know everything is connected. Things will be affected further and further down the valley. Species that had been in equilibrium might then have to compete for fewer resources.” And when it comes to a commodity that’s already in short supply—water—there will be even less for our rivers, and for agricultural, commercial, and municipal uses. Beyond that, it could be that we would lose some of the essence of Colorado.
“Glaciers are icons of the unique wild environments at high elevation in the Rocky Mountains,” says Williams. “When the glaciers are gone, we’ll all have lost part of our soul.”
OUT YOU GO
Near the Indian Peaks Wilderness Area
Start Fourth of July trailhead, near Nederland
Mileage 3.5 miles to the saddle between South Arapaho Peak and Caribou Peak
Tip Many hikers climb to the summit of South Arapaho Peak (13,397 feet) after reaching the glacier overlook. There is the further option of traversing along the ridge from South Arapaho Peak to North Arapaho Peak, which at 13,502 feet is the highest mountain in the Indian Peaks Wilderness area.
Did you know? In 1927, the city of Boulder acquired the Arapaho Glacier as part of a 3,685- acre land purchase from the federal government for the purpose of protecting the city’s water supply. Boulder now has the distinction of being the only city in the United States that owns a glacier. Several pristine lakes further down the valley are also owned by the city and, like the glacier, are strictly off limits to the public.
OUT YOU GO
Rocky Mountain National Park
Start Bear Lake trailhead
Mileage 1.8 miles to Emerald Lake; 1 mile of steep scrambling with 1,800 feet of elevation gain through the talus of Tyndall Gorge. Approach Start from Bear Lake, heading left towards Nymph, Dream, and Emerald Lakes. Though this area sees the most tourist traffic of any trail system in the park, the hike offers remarkable beauty. The trail ends at gorgeous Emerald Lake. From here, head to the south of the lake below the impressive north face of Hallet Peak. Once above the steep section, continue up a series of ramps and gullies, choosing the path of least resistance. The final obstacle before you reach the glacier’s snout is the rubble of a terminal moraine.
Tip After climbing through the boulders of Tyndall Gorge, you may want to (a) climb the glacier (which would warrant the use of ice axe and crampons, at a minimum); or (b) scramble to the north side of the glacier reaching the summit of Flattop Mountain. From here, you can either walk south along the Continental Divide and descend Andrews Glacier or descend via the Flattop Mountain Trail, 4.4 miles back to Bear Lake.
Did you know? Rock glaciers exist below Taylor and Tyndall Glaciers, as well as in many other locations without glaciers. If you visit them, be careful, as the surfaces of rock glaciers are extremely unstable. Rock glaciers are large masses of rock that actively flow like a glacier. The complex mixtures of ice and rock found in the park flow downhill at speeds of up to 20 centimeters per year. While rock glaciers have a characteristic glacier- or lava-like appearance from the air, they can be hard to recognize on the ground, resembling nothing more than a talus slope.
OUT YOU GO
Rocky Mountain National Park
Start Glacier Gorge trailhead, south of Moraine Park (near Bear Lake)
Mileage 5.3 miles, one way
Elevation Gain 2,510 feet
Approach Hike towards Loch Vale, passing Alberta Falls along the way. Turn right at the trail junction just beyond Embryo Lake and head towards Andrews Glacier. Look for The Sharkstooth to the south as you hike through The Gash.
Did you know? Although glaciers always flow downhill, the idea of glacier “retreat” may give the impression that a glacier can move uphill. In fact, a glacier is in retreat when it is melting back faster than it is moving downhill.
This article originally appeared in the Winter 2010 Issue (1005) of Trail & Timberline.