Story and photos By Oliver Lazenby
Investigate the terminus of the Easton Glacier on the south side of Mt. Baker and you might notice a ridge a few feet high of piled volcanic rubble about 25 meters from the edge of the glacier. That ridge, sculpted by a mass of ice and rock, is where the glacier ended last summer.
A similar distance downslope is another subtle ridge of dark, loose rock arcing across the slope – the glacier’s terminus from two summers ago. Beyond that, and even fainter, is another.
In August, when glaciologist Mauri Pelto arrived to study the Easton Glacier, its insulating snow cover was gone. Next summer, there will be another short ridge of pulverized dust and rock. The glacier’s snout will be a little higher up the mountain.
Pelto, a researcher from Nichols College in Dudley, Massachusetts, has returned to the North Cascades every summer for 33 years. He studies about 10 glaciers in depth and tracks about 45. For all but a handful of those years, the glaciers he studies have lost mass.
Pelto made headlines around the U.S. last year when he called 2015 a disastrous year for glaciers in the North Cascades. A terrible winter for skiers, followed by a warmer-than-usual spring melted more ice than any other year in Pelto’s study. By Pelto’s measurements, most glaciers lost about 5 percent of their total mass that year.
Summer 2016 was closer to a normal winter and spring, which, if you’re a glacier, is still bad. At the Easton Glacier, Pelto assessed the situation.
“It’s not a good year if you have this much blue ice already and you still have six good weeks of melt left,” Pelto said. “But it’s not going to be a terrible year.”
After the season wrapped up, Pelto found that on average, the glaciers he studies lost 1 or 2 percent of their total mass. During the time he’s studied North Cascade glaciers, the average yearly loss of mass has been about 0.5 percent yearly.
Pelto started the project in 1984, but didn’t start studying the Easton Glacier until 1990. That year, he pitched his tent at the bottom of the glacier. Now, the time it takes to walk to camp from the glacier’s melting snout takes minutes.
On his way back to camp after a day of research on the glacier – spent mostly probing and measuring snow cover – Pelto passed a familiar boulder. It’s where a 28-year-old Pelto strapped on his crampons in 1990 before crunching off up the Styrofoam ice of the glacier’s terminus. Now, on a foggy day, the glacier is hardly visible from that rock.
“I can see the glacier, but barely,” Pelto said. “It’s a big change.”
His tent doesn’t even appear to be in the same drainage as the Easton – the lobe of ice he pitched it below on that first year no longer exists.
Pelto’s research in the North Cascades is notable for its thoroughness. There are now similar projects elsewhere in North America – Pelto’s son Ben has measured glaciers in the Selkirk Mountains of interior British Co
lumbia. But Pelto’s the only one who has returned to the same glaciers for 33 years, and he plans to continue another 17.
I anticipated that it would be good to watch some of these smaller ones and they might disappear, I just didn’t think it would happen as fast as it did.
– Mauri Pelto, glaciologist
Since then, he’s seen a handful of glaciers effectively disappear, including the North White Chuck, the Spider and the Lewis glaciers.
“I anticipated that it would be good to watch some of these smaller ones and they might disappear, I just didn’t think it would happen as fast as it did,” he said.
The 50-year commitment comes with challenges, Pelto said. Each summer he spends a couple of weeks in spectacular campsites in the North Cascades, but also slogging around on glaciers in the rain, taking measurements before retreating to a tent. On the Easton, his group of researchers climb 3,000 vertical feet in a day to get measurements at higher elevations on the mountain.
“You can’t just pop out here, particularly in your 50s, and hike up and down a mountain for 50 days in a row. So I start training right after ski season,” he said.
High enough on the Easton and other glaciers on Mt. Baker, Pelto takes measurements of ice that isn’t shrinking. At about 2,500 meters (8,200 feet) the change is minor, even in years like 2015. That means that the glacier could reach a new “equilibrium point” higher up the mountain and eventually stop retreating. Where or when? It’s hard to say while the amount of heat-trapping gases pouring out of tailpipes across the planet continues to grow.
Pelto loves snow and has an emotional response to shrinking glaciers. It’s not clear why, but he shows some optimism in a blog post summarizing the 2016 season.
“We anticipate that this winter will be cooler and next summer the glaciers happier,” he wrote on his blog.
Whatever happens, he’ll be there to measure it. x