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Time Erases Glacial Landmarks from Mission, Swan Mountains

Montana's summit highlights are fading away

By ROB CHANEY, Missoulian

MISSOULA — Time takes away old friends, and it’s been rough on Rick Graetz.

As a young man, Graetz had a goal to climb every peak in the Missions. He hiked all over Montana’s mountains in the 1970s, gathering photos for the pages of Montana Magazine and a litany of books.

Along the way, he got to know a handful of small glaciers hidden around highways 83 and 93 north of Missoula.

“On McDonald Peak, we got on this notch right above the glacier, and here was a grizzly bear,” Graetz said, looking at an aerial photo of the icefield visible from U.S. Highway 93 near Ronan. “It was sliding on the ice. And Glacier Peak’s glacier used to calve icebergs into Lake of the Clouds. Now they’re the only two glaciers left in the Missions.

“We’d go in from Lion Creek to see Sunburst Glacier back when it reached almost to the summit of Swan Peak. Now it and Stanton Glacier on Great Northern Mountain are probably the only ones left in the Bob Marshall country. There’s 3.5 million acres there and only two glaciers left.”

Graetz bagged many of those peaks with mentor Bill Kuhr. He now teaches geology at UM’s Crown of the Continent Initiative.

This fall, Graetz flew both the Mission and Swan Crest mountains with pilot and UM biology professor Rick Hauer, looking for the icefields that used to define them. They’d slow the plane to 70 mph, lift the passenger-side window and watch the sunrise on the snow.

What they saw was consistent with the news out of Glacier National Park to the north — Montana’s summit highlights are fading away. Where once climbers would have strapped on crampons and swung ice axes to reach a peak, now a dry and rocky path awaits.

“All these cool names up in the Missions — Lake of the Stars, Pass of the Winds, Angel’s Bathing Pool – they should have ice,” Graetz said. “That really bummed me out.”

The Missions aren’t the wettest mountain range in Montana — the Cabinets and Scotchmans in the northwest corner of the state hold that title.

But with a vertical rise of about 6,000 feet from the floor of the Mission Valley to the top of McDonald Peak, they strip a lot of moisture out of passing storms. That’s allowed moving icefields to persist since the last ice age of the Pleistocene Era that ended about 12,000 years ago.

Graetz said some of his students struggle to believe the Mission Valley used to be filled with ice 3,000 feet deep around those peaks. He proves it with photos of the striations, or grooves etched in the summit ridges by rocks dragged by passing glaciers, and of eroded boulders known as glacial erratics carried and deposited far above the geological formations from which they came.

Today, it takes ice at least 25 acres around, 150 feet thick and moving to qualify as a glacier. By that rule, most of the white masses in the Missions and Swan Crest have downgraded to permanent snowfields or stagnant ice.

“The Missions are a miniature Glacier Park,” Graetz said. “It’s the same sort of sedimentary rock formed by glaciers.”

And it’s suffering the same fate. Glacier National Park claimed 150 glaciers when it was explored in the late 1800s. Today, the count is down to 25 and probably due to drop more after results from this fall’s inventory are tallied.

Grinnell Glacier, one of the park’s largest, reportedly lost a 23-acre chunk to calving this summer.

There’s a possibility that two more glaciers remain active in the Bob Marshall area — one near Cliff Mountain along the Chinese Wall and one in the Flathead Alps area at the headwaters of the South Fork of the Flathead River. Weather permitting, Graetz and Hauer plan for one more flight this fall to check on those.

“Some people say, ‘Who cares? – they don’t add much to the water supply.’ ” Graetz said. “But they’re part of the wild country we’ve come to know. They’re sort of friends to you – and they’re gone.”