Disappearing glaciers give scientists new insights

There is perhaps no feature more prominent in the discussion of climate science than the disappearance of glaciers. In Glacier National Park, this rings especially true. 

U.S. Geological Survey (USGS) research ecologist Dan Fagre has traveled the world conducting research on glaciers and mountain ecosystems. After working for more than 29 years in Glacier National Park, he knows Montana's glaciers better than most.

"People like glaciers," he said. "They like to see them. A lot of people come to Glacier Park and the first thing they want to do is see a glacier. It's our charismatic geological phenomenon." 

The eyes of the nation are on Glacier as climate change takes a visible toll on the park. While some early climate change models predicted that all of the park's glaciers would disappear by 2030, Fagre said this might not be the best predictor of what will actually happen.

"That model did not account for things we've learned since then so the glaciers may have a little more time," he said. "Other recent models show glaciers gone by 2050 or later. But what we can say for certain is that these glaciers have been around 7,000 years, and they'll be gone in just decades. Not centuries, just decades. The exact date that they're all gone isn't as important as the fact that they're disappearing."

As a leading member of the Climate Change in Mountain Ecosystems (CCME) team, Fagre collects and analyzes data about the glaciers in Glacier National Park. Part of the team's glacier monitoring project includes comparing records of glaciers in Alaska and Washington, as well as Sperry Glacier inside the park. While the other glaciers have records that stem back to the 1950s and '60s, Sperry has only been observed this way since 2005.

"We don't have as long a track record, but we've got to start sometime. We intend to follow Sperry until it is no more," Fagre said.

Mountain ecosystems are particularly sensitive to temperature changes because they are generally cooler to begin with,and less year-round snow increases heat absorption, Fagre said. Several species of insects that were recently added to the Endangered Species list experience the direct effects of climate change on glaciers and snow.

"They're highly dependent on cold water," Fagre said. "So when you have your snowpacks becoming a little more erratic and not as large, and you have the glaciers disappearing as well as part of the same phenomenon, you don't have to be a rocket scientist to see that the environmental requirements that they need are changing in a negative way."

Sensitive organisms are feeling the impacts now and are likely to decline in the near future, while others may take a long time to show impacts, Fagre said. "The story is that there are always animals that gain ground. There are animals that will benefit from climate change."

Many have noted the mountain pine beetle's flourishing condition in the last few years, for example.

In addition to these direct effects, melting glaciers also serve as an easily observed indicator of dramatic changes taking place.

"Part of the reason glaciers disappearing is so important is that they're a warning system-it's like the red alarm light flashing in the cockpit before you go down," Fagre said.

In some areas of the world, such as the Himalayas, people are directly reliant on glaciers for potable water. These areas are also particularly susceptible to physical dangers that affect the people living nearby. 

"As glaciers retreat in other areas, not here in Montana because ours are so small, it opens up really large areas of unstable landscape," Fagre said. "A lot of areas where glaciers have retreated, you have all this glacier debris sediment that can clog up rivers as they get washed away, can collapse, and cause different kinds of landslide hazards."

While Montana's glaciers are too small to significantly affect the water supply, their disappearance is in line with the yearly snowpack, which is a major source of water for this region.

"The glaciers are secondary in water importance but primary in making us alarmed by changes we see," Fagre said. 

"Alarm" isn't necessarily a negative thing: sudden changes such as melting glacial ice prompt scientific study and potential action, giving scientists more data than ever before to better understand the way glaciers work.

"If climate change affects something that is so visually obvious and that people understand depends on being cold," Fagre said. "Regardless of the actual direct effects on people, which can be difficult to visualize, the melting of glaciers forces people to confront the fact that the whole world is changing...I think the visual warning of ice melting is probably its number one value."