Wednesday, May 10, 2017

Glacier National Park Is Losing Its Glaciers

By Andrea Thompson
May 10, 2017

Glacier National Park is losing its namesake glaciers and new research shows just how quickly: Over the past 50 years, 39 of the parks glaciers have shrunk dramatically, some by as much as 85 percent.

Of the 150 glaciers that existed it the park in the late 19th century, only 26 remain.

“The trend is consistent, there’s been no reversal,” Daniel Fagre, the U.S. Geological Survey scientist who led the research, said.

The loss of glaciers potentially affects not just tourism to the park, which hit a record 2.9 million visitors last year, but also local ecosystems that depend on the summer release of glacial meltwater.

The pristine, 1 million-acre park sits along the border with Canada in Montana and has long been a poster child for climate change in U.S. national parks. Side-by-side photo comparisons show in the starkest terms just how far some glaciers have retreated, with some only reduced to small nubs of ice.

The retreat has happened as temperatures in the region have risen by 1.5°F since 1895 as heat-trapping greenhouse gases have continued to accumulate in the atmosphere.

A 2014 study found that it is this human-caused warming that accounts for the bulk of worldwide glacier loss over the past few decades.


How quickly the remaining glaciers might go is hard to predict, as relatively cool years can afford a small reprieve, but hot years can push glaciers already on the brink below the 25-acre threshold used to define a glacier.

“The most important aspect of this is that the process is only going in one direction,” Fagre said. “They’re all inexorably going to that ultimate fate.”

The newly released data is part of an ongoing USGS effort to monitor glacier change in Montana, Alaska and Washington.

Understanding how glaciers are changing is important because they play a key role in local ecosystems. Summer meltwater helps top up streams that might otherwise run dry and many species are highly adapted to the cold temperatures of the water, Fagre said.

The subject of national parks and monuments has recently become a contentious one, with the Trump administration recently ordering the Interior Department to review all large national monuments to recommend ways to shrink or abolish them. The order is part of a larger effort by the administration to open up fossil fuel development on federal lands.



“The park-wide loss of ice can have ecological effects on aquatic species by changing stream water volume, water temperature and run-off timing in the higher elevations of the park,” said lead USGS scientist Dr. Daniel Fagre.

Portland State geologist Andrew G. Fountain partnered with USGS on the project. He said glaciers in mountain ranges throughout the United States and the world have been shrinking for decades.

“While the shrinkage in Montana is more severe than some other places in the U.S., it is in line with trends that have been happening on a global scale,” Fountain said.


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