Glacier Park scientist talks climate change in mountain ecosystems

Over his 29 years working in Glacier National Park, U.S. Geological Survey (USGS) research ecologist Dan Fagre has seen a lot of changes. Even as the pressures of climate change encroach upon this mountain region, Fagre and other scientists see boundless opportunities for research and education.

Fagre and other members of the USGS Climate Change and Mountain Ecosystems (CCME) Program focus on alpine climatology, snowpack, snow avalanches, alpine vegetation, and glaciers for most of their research. While some of these phenomena are not considered strictly ecological, Fagre said that the way the team studies them definitely is. 

"For instance, when we look at snow avalanches, we not only look at them from the typical physical science perspective, but we look at their impacts on mountain ecosystems," Fagre said. "We're very interested in the fact that they are a disturbance agent in the mountain system. A certain amount of disturbance is necessary to maintain what we have, but if you get excess disturbance, then it can be destructive. Analogies to forest fires come to mind."

Depending on the type of project, the CCME research team consists of 6-8 people with a wide range of scientific expertise between them. All of them have a deep passion for the mountains-even spending their days off on them, skiing and hiking when they can.

The mountains are what drew Fagre to Montana in the first place. Born in Minnesota, he moved around frequently as a child and even spent nine years living in Tokyo, Japan. He went to college in Arizona and spent time climbing in Mexico, California, and Colorado. He came to Montana in 1991, and has worked for the USGS in Glacier National Park ever since. He anticipates retiring in 2020, but says he still has projects to finish up-"which is always the case with scientists," he said. "That last paper." In this case: a chapter on mountain glaciers for a climate change textbook, and an alpine vegetation change study.

As Fagre looks to retire within the next year, he expects PhD student and avalanche expert Erich Peitzsch to take over for him. Peitzsch is currently the vice president of the American Avalanche Association.

CCME is hands-on: on a given day, data collection might include skiing into a key location, digging a snow pit, and using a thermometer to measure the snow temperature profile from the ground up to the surface. The size and type of snow crystals present are also recorded. In combination, these factors can indicate which areas are more likely to release a snow avalanche. 

Most of the CCME's work has been above the treeline; in recent years, the team has started using drones to map avalanche zones where it's too dangerous for researchers to ski. 

For years, CCME has worked closely with the staff of Glacier National Park, Fagre said. "We've taken part in many initiatives over time, many through the Crown of the Continent Research and Learning Center."

Within the park, CCME works with snowplow operators in the spring, trains park interpreters, conducts avalanche safety trainings, and communicates scientific research to park employees to share with park visitors and the general public.

The work of Fagre and his colleagues on avalanche forecasting is also tied to regional economics. "Tourists just don't come to the park in the spring until Going to the Sun Road's open and forecasting helps to safely open the road," he said. "So you have that as a socioeconomic component, and you have the very same thing, snow avalanches, being instrumental at a mountain ecosystem scale...We try to do science that is relevant to the long-term management of the park."

Avalanches and climate change in Glacier National Park

In the high reaches of Glacier National Park, the captivating beauty of the mountains holds a powerful wintertime phenomenon: snow avalanches.

Avalanches are often dramatized as extremely dangerous, freak events, but they are a natural part of the Glacier National Park ecosystem. U.S. Geological Survey (USGS) research ecologist Dan Fagre and his colleagues are responsible for recording and researching the predictors of avalanche release in the park, all under the umbrella of the Climate Change and Mountain Ecosystems (CCME) Program.

There are 48 active avalanche paths along Going to the Sun Road, the main route visitors take when driving through Glacier National Park. Scientific analysis shows that at upper levels, each avalanche path is likely to release every two to four years. 

"The really big ones that rip all the way down to the bottom and would knock a train off the tracks or cause real damage are about one every decade," Fagre said.

Small avalanches are more frequent, but their frequency is complicated by the fact that some winters are more active than others.

The impacts of avalanches in the park are wide-reaching: seasonal avalanches directly affect the behavior of grizzly bears, for example. Avalanche chutes provide ideal foraging areas for bears.

"You have that low shrubby vegetation; a lot of herbaceous plant cover that is highly nutritious for all kinds of things-bears and birds and bees are all using these avalanche chutes. So this is keeping biodiversity at a higher level than wouldotherwise occur and maintains habitat heterogeneity," Fagre said. 

Avalanches are known to cause animal mortality, but have bigger effects on the ecosystem at large, including aquatic systems.

"They bring a huge amount of debris down into a streambed, changing all of the dissolved organic carbon and the dissolved organic nitrogen," Fagre explained. "Then the trees, when they pile in the streambed, can create more shaded habitat for trout, or alternatively, depending on how the snow avalanche piles up and changes the stream course, you might lose some, too." 

The effects of snow avalanches are similar to the ways forest fires reshape the mountain ecosystem, Fagre said. "And that's not even considering the role of snow as a hydrologic reserve, in terms of water supply."

In areas where debris has piled up, it can take the snow up to three years to melt. This is extremely compressed snow, which can be as deep as 40 or 50 feet. "All the woody debris on top of it helps insulate it," Fagre explained.

In addition to these direct ecological effects, avalanches also have a unique interaction with fire. 

"Snow avalanche paths are fuel breaks," he said. "They affect how fires move across the landscape. So you have this interaction between snow and fire that a lot of people don't think about."

As the planet warms, researchers are concerned about a future time when there are no snow avalanches, Fagre said.

"That's very likely just because the average snow line is going up," he explained. "We have 2-3 weeks of less snow on the ground at any particular point. There have been many snow survey sites that were started in the last century-some of them don't have snow anymore."

In October 2020, Fernie, B.C. will host the International Snow Science Workshop (ISSW). Snow and avalanche specialists around the world will gather to exchange interdisciplinary ideas and experiences. 

"It's international, but it's in our neighborhood," Fagre said. As CCME continues to gather important data about snow avalanches in Glacier National Park, it will be exciting for the team to have a seat at this global table of mountain experts, convened just over the border in their own backyard.

"Snow avalanches are much more important than whether it's a hazard to a skier or whether it means that Going to the Sun Road can't open up a couple weeks earlier," Fagre said.