Century of climbers' notes from alpine shelter offer glimpse of changing peaks

The view from the shore of Lake Louise appears like a perfectly framed photo of the Rockies built by nature: the turquoise water leading the eye to a central point, where two dark and treed mountains guard a glacier-adorned pass.

It's a view that, for more than a century, has drawn tourists from around the world and beckoned climbers looking for the next challenge.

These mountaineers trod a well-worn path, trekking to Abbot Pass. That alone is a difficult climb. But for those looking to reach new heights, Abbot is a gateway to bigger feats: the summits of Mount Lefroy and Mount Victoria.

Along the way, climbers left their mark, a record of their trips jotted into a register in a stone-built refuge known as Abbot Hut.

These drawings, songs and scribbles are personal — proof that thousands of people made it to the same slice of the Rockies.

But these entries provide more than just cultural and historical value. They’ve helped complete a picture of how the mountains surrounding Lake Louise are transforming in a warming climate.

New research from the University of Calgary examined the two most common approaches to Abbot Pass, and how a warming climate has changed access and safety.

The paper relies on data from Environment and Climate Change Canada’s weather station at Banff and is complemented by 100 years of summit register entries. 

Mountaineers documented their trips and choices on the Swiss Guide route, more commonly known today as the “Death Trap” and Lake O’Hara Gully. 

The result is a unique piece of research that centres the local experience in climate science. 

images expandThe difficult climb to Abbot Pass became more accessible to hikers of all ages and levels after Abbot Hut was built in 1922.

Kate Hanly is a PhD candidate in the U of C’s department of geography and the lead author of the research paper.

She says the trend, reflected in the climate data and the summit registers of generations of climbers, is clear: “We’re seeing less glaciers, less snow, faster melting snow.

“Climbers are climbing increasingly on rock or on loose scree, the material that was underlying the ice, and they're seeing more rockfall.”

But these historical notes logged over time also have another story to tell: one of adaptation to the climate reality that mountaineers are facing.

“It just reminds us of what we have to lose,” Hanly said. “It's so much more than a hike.” 

Hanly spent only one night in Abbot Hut. In 2012, she made the journey with her father, guided by Albi Sole, a well-known mountaineer who taught at the University of Calgary’s Outdoor Centre. The view and the experience left an impression.

“It was the first glacier we walked on together and the first kind of bigger hike for [my dad] and he was so proud of himself, as he should be,” Hanly said. 

At that time, Hanly was just beginning to spend more time in the mountains — and the more she visited the landscape, the more she thought about how it was changing.

For those who live in the Bow Valley west of Calgary, this is a universal experience and part of daily conversations.

Locals wonder if the experiences that drew them to live in the Bow Valley are in danger of becoming extinct, a loss for the next generation.

“I wanted to understand, well, OK, like, yeah, these are changing, but is there a systematic way to understand these lived experiences of change in the Rockies?”

Hanly decided to zoom in and photograph how some of the most-visited or iconic pieces of the landscape were changing.

With a research grant in 2022, she hired one of North America's most successful alpinists, Barry Blanchard. Hanly planned to snap a picture on the route to Abbot Pass framed to perfectly line up with an archival shot of the Swiss Guide route — the original approach to Abbot Hut.

This route is better known as the “Death Trap” — a nickname assigned as a warning to climbers because of the risky terrain. The narrow passage is prone to avalanches. It features a crevassed glacier that can be extremely difficult to cross. And there is always a risk of rocks or chunks of ice raining down from overhead.

Things had changed since her last visit a decade before.

“It was really scary,” Hanly said. “It actually felt like the death trap.”

The pass gets its name from Philip Stanley Abbot, a mountaineer and American lawyer who died from a fall during the first known attempt to reach the summit of Mount Lefroy in 1896.

The following year, a group of alpinists climbed both Victoria and Lefroy and named the pass in between Abbot Pass, to honour their friend.

Canadian Pacific was building what would eventually become the Chateau Lake Louise that people know today: first as a cabin sleeping two, then a chalet sleeping 15. Swiss Guides became part of the experience, leading novice and skilled climbers on excursions.

In 1922, the guides and the CPR undertook the construction of a stone hut shelter.

Wranglers with horses inched up the mountainside with building materials, guided carefully through the pass. They carried heavy packs over a ladder to avoid a deadly crevasse. Today, that’s part of the romance of the place: walking up the pass, following in those footsteps. 
 

The next year, Abbot Hut was built from stone carved from that spot. It opened, and visitors began recording their trips in a book, known as a summit register.

Those records cover the lifespan of Abbot Hut, which was taken down in June 2022 as its foundation crumbled due to thawing permafrost.

While the hut is gone, thousands of entries from its old logs still exist at Banff’s Whyte Museum, part of a large collection of summit registers from the region. 

Today, many celebrate reaching a summit with an Instagram pic. It's an instinct that’s not new but a piece of human experience. It's a way to mark “I was here.”

Before smartphones and even cameras were commonplace, the accomplishment was conveyed in writing. Documents known as summit registers come in many forms.

“Sometimes it's the only record we really have of people's activity on a mountain,” said Kate Nielsen, an archivist at the Whyte Museum. 

She said the museum’s collection includes random finds made by climbers — like a single scrap of paper stashed in a film canister on a mountain top.

Other collections, saved by groups like the Alpine Club of Canada, have meticulously kept donated records. They detail the mountain culture of alpine huts.

“Just about anyone can find something that interests them in the hut registers,” Nielsen said.

She says the records tell a complicated story. Some of it is useful as a formal record of seasons, plants and animal observations. Other details, she says, are delightful crumbs of people’s lives: poems, inside jokes, scorecards marked with the winners and losers of games invented after a gruelling day of mountaineering, whose rules will never see the light of day

“It's got the family stories, it's got sometimes inappropriate content, which can be funny,” Nielsen said. 

images expandThe Whyte Museum of the Canadian Rockies keeps archives of summit registers and summit notes.

One of their most complete collections documenting the mountaineering community are the registers from Abbot Hut.

Among the names in those old registers is seasoned guide Albi Sole, who often signed for himself and his clients. Even though he often found coming up with something smart to say tough in the moment, this was an important part of the trip.

“It’s special for people to say my name’s in that book,” he said. “It’s an interesting thing, you know. Puts us in contact with a narrative, with a place, with the people that came before and the people that will come after.”

At first glance, Hanly was confident she’d get through the Abbot Hut registers in no time. Mountaineers in the early days kept their entries concise with just a name and the climb.

It took her a couple of hours to get through the first few decades, with entries helping her track how seasons were changing. 

As an example, one register that started in the 1950s had enough pages to stretch until the 1970s. But as the entries neared contemporary times, people turned single-line items into page-turners.

It was not the simple project she thought it would be, as the mountain of work piled up in front of her.

“They get increasingly verbose as you go throughout history, and you start getting like bad poetry or original songs or funny stories,” Hanly said.

Another gift was the detail that hikers were now sharing about the routes they chose and conditions encountered on the trek: climbing on snow, or bare ice, encounters with crevasses, accounts of rockfall and ice fall. Details she was tracking in a computer spreadsheet.

Kate Hanly, shown here looking at the hut's register entries, says the summer 2021 heat dome in Western Canada was 'the nail in the coffin' for the Abbot Pass Hut. Molly Segal/CBC

She logged 6,073 entries from the Abbot Hut registers and tracked changes over a century of mountaineering.

Based on the trends, she spoke with local mountain guides to verify the data and what the registers were saying. But sometimes a register would fill up and not get swapped out for a new one, or pack rats moved into the hut and ate through entries. Other times pages were torn out to help start fires.

Where there were gaps, Hanly turned to the Mountain Condition Reports, a digital asset that began in 2005 and is ongoing, exclusively written by guides.

“It's definitely not a perfect record by any means, but I think it's a good snapshot of where things were at and how things have changed,” Hanly said. 

Another complicating factor was the fact that, as Hanly pointed out, Canadian weather data is far from perfect.

Canadian researchers have pointed out that the country has seen the number of weather stations collecting key information dwindle — and those blips in information can muddy understanding and climate model predictions.

• UPEI researchers install 39 weather stations to 'fill in the grid' for climate information
• Weather stations are sparse in Labrador. The gaps can be a matter of 'life or death'

What the weather data showed over time was statistically significant: Banff National Park has seen a total temperature increase of 0.97 degrees Celsius since 1887. And since 2000, the rate of warming has increased five-fold.

That change was also reflected in the registers.

In the beginning, the Swiss Guide route was the most popular approach to reach Abbot Hut, with a majority of trips taken from the Lake Louise side, instead of the Lake O’Hara Gully route.

Then, from 1974 onward, favour flipped, with 79 per cent of trips recorded from the Lake O’Hara approach.

After 2015, Hanly said, the original route was abandoned.

“It still gets used occasionally in a good snow year for a spring ski descent or ascent. But predominantly, people are going up from the O'Hara side,” Hanly said. 
 

Mount Victoria and Mount Lefroy are the two objectives people climb Abbot Pass to reach. Entries in the register also shed light on how those climbs are changing.

Without snow, Lefroy is a loose and rocky face that’s not a pleasant climb. A bit of snow and ice make it easier to summit. Reading through the registers, the climbing season for Lefroy started short, which Hanly said is due to limitations in climbing technology and technique, along with concerns about avalanche hazards.

Hiking toward the Death Trap in September 2022. Submitted by Kate Kanly

As mountaineers got better, the season expanded — to a point. In the 2000s, the season got shorter again.

“There’s either less snow or it's melting out crazy fast, so there's a very short window where that route is actually safe or in condition.”

Mount Victoria is a different story. It's a climb that can be done in snow or snow-free conditions and has seen the window for safe treks expand.

At every turn, Hanly saw guides adapt. 

It’s an integral part of the job, Sole explains. Conditions on a mountain aren’t the same day to day, and they shift across the season.

Those are the rhythms he’s grown used to. Early in the season, there’s a lot of snow and corniced ridges. This eventually melts away so that same climb is on rock instead of powder.

“It’s a living thing, in a sense,” he said.

Throughout his career, Sole watched those seasons evolve. He learned to plan for more variability — for the glacier to look a lot different from one season to the next, to start a season with less snow than normal, and to melt sooner.

In some places, he said, those changes make climbs easier, while in others, things get more dangerous.

“There's always been climate change. It's accelerating. It's very fast now and we really need to concentrate on how we're going to adapt,” Sole said. “There's no point crying over what you can't change, but just buckle down.” 

Sole believes the mountaineering community 100 years from now will be guiding on a transformed landscape.

And like mountaineers, people are incredibly adaptable, too, he says with the ability to take the lot that’s been handed to them and make something from it.

This is where the sport meets philosophy for Sole.

“We need to note the changes, maybe give them some respect, but recognize that the only constant is change,” he said. “We can make a great life for ourselves and the people around us if we keep that optimism.”

Hanly said this research shows the value mountain guides offer beyond the individual experiences they provide.

They are the eyes and ears of Canada’s alpine spaces, with insights and expertise that she said sometimes aren’t recognized.

Hanly said summit registers have provided something important. They have provided a  tangible example of climate change that’s not difficult to understand, and not so big and broad that it overwhelms.

“When people say, oh, there is x amount of CO2 in the atmosphere, you can’t see it,” she said.

But Lake Louise? That you can see.

The turquoise waters and glacier-adorned ridges are something seen by millions every year. Hanly hopes the story behind the landscape and how it’s changing will be as impactful and inspiring as the scenery.