By Daniel G. Graetzer, Ph.D.
Faculty Member, School of Health Sciences
When it was designated as a national park by President William Taft in 1910, Glacier Park in northwest Montana had about 150 official glaciers. Unfortunately, the current number of official glaciers has shrunk to 25 in 2021. Many glaciologists are now predicting that the melting will continue at such a fast rate that this famous park might actually be glacier-less around 2030.
Glacier National Park was once considered the crown of the North American ecosystem, with the famous Grinnell Glacier (named for George Bird Grinnell, an explorer who championed the park’s designation) considered one of the park’s crown jewels. But it is unlikely that Glacier National Park will be renamed “Glacier-Less Park.” This name would be a permanent admission of government policy failures, due to the U.S. government’s refusal to acknowledge numerous warnings of global warming from the past.
Related link: Climate Change: Practical Steps That We Can Take Today
What Are Glaciers?
Glaciers are formally defined by glaciologists as bodies of snow and ice that move under their own weight – often by about 10 feet per year. Most glaciers in Glacier National Park are relatively small cirque glaciers within alpine basins along the Continental Divide.
Within Glacier National Park, ice bodies are classified as glaciers when their area exceeds 0.1 km2 (100,000 m2) or about 25 acres, according to the U.S. Geological Survey (USGS). A glacier that is reduced to smaller than 25 acres often has minimal movement and reduced ice flow and shift, causing less release of nutrients as the glacier grinds against rocks.
Crevasses – large cracks created by the dynamic movement of the glacier – are formed in response to area temperature and precipitation. They grow when winter snowfall exceeds summer melting, and they shrink when melting outpaces new snow accumulation.
All of the glaciers in Glacier Park have decreased in size, but their rates of decrease vary widely. Variations in a glacier’s initial size, ice thickness, elevation, shading, geometry, avalanches and the degree of wind-deposited snow cause unique rates of change.
Montana Is Warming at Almost Twice the Speed of the Global Average
Montana is now warming nearly twice as fast as the global average; warmer winters have brought more rain, rather than glacier-forming snow. Also, the increasing heat in spring and summer has melted the glaciers in Glacier National Park. Spring snow melts are now occurring at least two weeks earlier than they were in the 1960s.
Typically, the USGS uses aerial photographs and satellite imagery to track glacier changes such as a glacier’s area and margins and to estimate changes in the water stored within the glacier. The size of the glaciers in Glacier National Park have certainly waxed and waned with various climate fluctuations since their formation, but now is probably the first time the damage may be irreversible.
Why the Changes to Glacier National Park’s Glaciers Are Significant
Disruptions in any delicate ecological chain cause a cascade of other changes in regard to vegetation, forest structure, animal migration, severity of forest fires, stress from drought and the warming of rivers as a snowpack recedes. Outdoor enthusiasts have already noticed that some species of trout in Glacier National Park are less abundant. In addition, grizzly bears have moved on from some regions due to the loss of white bark pine trees, which they depend on.
Glacier National Park’s three million annual visitors will probably always be able to see white snow on the park’s mountains. However, it is questionable how much of that snow will still be considered as a part of a glacier if current climate changes continue.
Grinnell Glacier’s towering ice, previously hundreds of feet thick, is now reduced to about two feet in many areas and some regions now show visible dripping. Runoff from Grinnell Glacier has spawned a new lake, the Upper Grinnell Lake, which often contains icebergs broken off from higher up the glacier.
Many people fear that further melting will cause Glacier National Park to lose its identity. Sadly, the dramatic recession of Grinnell and other glaciers may soon cause Glacier National Park to become a permanent symbol of what climate change has done to our environment.
I personally take my family to Glacier National Park at least once every summer to pay my respects to the glaciers that once shaped the Earth. For me and many others, the permanent loss of these previously massive and magnificent glaciers is comparable to the potential loss of national symbols such as the Statue of Liberty or Mount Rushmore.
There are several ongoing Glacier Park community discussions led by environmentalists regarding this alarming glacier shrinkage data. In addition, there may be more wildlife educational programs, limits to local traffic, and burn bans to reduce forest fire risk possibly being implemented in the summer of 2022.