Glacier Ice Fields May be Gone by Next Decade

On the eve of Glacier National Park’s 100th birthday, some of its distinctive features — glaciers — are disappearing and may not be around for the park’s bicentennial party.

The parks’ remaining glaciers might not last longer than the next decade, said Dan Fagre, a U.S. Geological Survey mountain ecologist who has been studying the park’s glaciers for 18 years.

Glaciers are created when snow falling over many years is compacted into ice. For an ice field to be classified as a glacier, it must be more than 25 acres in size, be on the move and sculpt the landscape.

A 2003 study predicted park glaciers might be gone by 2030. But, because temperatures are warming at a more rapid rate than a few years ago, glaciers could disappear by 2020, Fagre said. In 1900, about 150 glaciers lay in what is now the national park.

Now only 25 glaciers are 25 acres or larger, Fagre said.

Although the size and number of glaciers have been decreasing over the past century, glaciers now are shrinking at three to four times the rate that they were in the 1950s and 1960s.

The reason is warmer temperatures.

Although Glacier is relatively cool compared with many other parts of the world, temperatures in the park have increased two to three times as much as than the global average temperature increase, Fagre said.

Glaciers don’t take sides in the debate over whether that increased heat is natural or manmade.

But there’s no debate over the fact that temperatures are getting warmer and glaciers are getting smaller.

Based on aerial surveys, photos and data from monitoring devices used by Fagre and others, including University of Montana researchers, every glacier could disappear over the next 10 years, although some ice fields might remain.

Although glaciers can be replenished during years with high snowfalls and mild summers, those types of years haven’t outnumbered glacier-depleting years of drier winters and hot summers, Fagre said.

The largest glacier in the park now is Blackfoot Glacier, which is about 445 acres. It is south of Logan Pass and is visible from the Going-to-the-Sun Road.

Some of the park’s present-day glaciers have been around for 7,000 years, although the ice doesn’t date back that far. When conditions are right, new ice is made while older ice melts. The ice in today’s glaciers is only three to four decades old.

The glaciers that survive today are not the huge glaciers that carved the distinctive topography between 18,000 and 12,000 years ago.

Glaciers are disappearing all over the globe from the Andes to the Himalayans. Ninety-nine percent of Alaska’s glaciers are shrinking, including one that has retreated 50 miles over many years.

If glaciers do disappear, species of plants and animals that depend on them might vanish, too.

The alpine poppy needs moisture through the summer. Living at the edge of glaciers, the small flower soaks up water from melting ice.

Some animals, too, have adapted to life near glaciers.

During the driest, hottest part of the year in August, stream flows drop and can go dry, dooming some aquatic life.

The drip from glaciers provides cold water for fish such as the bull trout — nicknamed the “polar bear of trout” — that could die off if not enough chilled water reaches streams where they live.

If the glaciers disappear, the park’s name will remain because it was named after the glaciation process that created Glacier’s dramatic mountains, not glaciers themselves, said Amy Vanderbilt, a park spokeswoman.