Following the paved walkway to the Peyto Lake lookout, Scott Munro soon arrived at the dirt trail branching from the popular tourist viewpoint. Dropping downhill through old-growth spruce forest, at the lakeshore he headed across gravel flats.
Hopping easily over a few late season shallow braids of water streaming like turquoise satin ribbons to fill the iconic lake, he passed dozens more dry grooves which creased the sandy, rock-strewn ground, evidence of the great amounts of water that have tumbled for centuries from Peyto Glacier four kilometres up the valley.
Continuing along the well-worn hiker’s trail, Munro expected to cross turbulent Peyto Creek via a footbridge further upstream. A professor of geography with the University of Toronto’s Mississauga campus, Munro had hiked the trail countless times en route to the glaciology research site perched atop the moraine at the glacier’s toe since he first visited the site in 1971 to work on his PhD.
On that day in October 2010, however, he noticed the watercourse was not flowing the way he remembered. A massive chunk of the lateral moraine had very recently collapsed, sending tonnes of rock down into the creekbed, destroying the wooden bridge and altering the course of the flow.
“The big boulder that was always a landmark was gone,” Munro recalled. “There was dirt where there had been water. The landscape was completely changed. Something had happened, and scraped off the side of the moraine. Every 100 years or so, these big events happen.”
Last month, Munro returned to the glacier, one of several researchers who spent nearly a week working on independent projects based out of the trio of weather-worn 1960s-era buildings.
Munro’s work involved dismantling and reassembling weather stations necessary to maintain his long-term glacier energy-balance studies. After sitting on the ice as last winter’s snow accumulated under the tripod-like station which supports instruments that measure precipitation, snow depth, wind speed and direction, the station appeared to be resting on stilts as the snow had since melted out under it.
Situated in the ablation zone at 2,183 metres elevation, that station has been moved up the glacier repeatedly since it was first installed in 1995. Since it was first photographed in 1896, Peyto has retreated four kilometres. Assisted by glaciology technician Steve Bertollo and field technician May Guan, Munro also tended to two higher sites at 2,461 and 2,709 metres.
“The lower one is the easiest to maintain,” Munro said. “The highest one in the accumulation zone is the toughest one to keep going; it’s high on the glacier so it’s exposed to lots of high wind and rough weather. The lower ones fall over, the top one gets buried. But, Peyto is one of the best instrumented sites anywhere. People have cared enough over the years to keep it going.”
Also conducting research, Mike Demuth, the Ottawa-based head of glaciology for Natural Resources Canada’s (NRC) glaciology department, teamed up with NRC colleague Mark Ednie, a permafrost specialist who maintains several sites in Canada’s far north, to continue studies as part of NRC’s long-term mass balance observations at the Peyto site.
Assisting them was Christophe Kinnard, a Canadian glaciologist visiting Peyto on a break from his current position with CEAZA institute in Chile, where he studies several glaciers similar in characteristics to Peyto. Part of an exchange program that saw Demuth visit Chile last January, the scientists compare and learn from each other’s projects and methods.
Following a 300-metre transect line they had marked with neon orange tape stuck on rocks at measured intervals, Kinnard and Ednie walked slowly across undulating rubbly terrain that comprises the moraines bordering the glacier’s north side. With Demuth carrying a monitor in a chest harness, Ednie and Kinnard stopped at 50-centimetre intervals to rest their radar assemblies on the ground to take a reading.
Back in Ottawa, the data will be analyzed to help determine how much freshwater may be stored in the ice core moraines, buried under centimetres or even metres of debris that has crashed down from the cliffs above.
As one of the longest-running glaciology sites in North America, where research has been continuous since the mid-1960s, the Peyto station represents not just a key component of Canada’s network of studied glaciers and their associated freshwater resources, but also part of a global network. Information gathered there is shared with the UN Framework Convention on Climate Change, as well as industries including mining, hydro power operators, irrigation, tourism, ecosystem services and by Alberta Environment to make water management and allocation decisions.
With many of the glaciers being studied as part of NRC’s reference observing network situated on federal lands in the mountain parks, Parks Canada uses the information for its mandated requirement to produce regular state of the park reports.
While most of Alberta’s river flow is maintained by rain and snowmelt, glaciers are nature’s reservoirs that kick in later in the summer during times of hot, sunny, dry weather. And, like the vast majority of glaciers the world over, Peyto, which feeds into the North Saskatchewan River, is rapidly shrinking, not just in length, but also width, depth, and naturally, volume. As such, both Demuth and Munro are looking ahead to establishing new research sites on other Rockies glaciers whose stages of decline are behind those of the Peyto.
“A lot of the big signal reference sites around the world are disappearing,” Demuth said. “The utility of Peyto Glacier as a glacier climate monitoring site is not long for this world. As this place disappears it’s an excellent place to study what’s being left behind, though. In this valley, more and more ice is being covered by debris. In time it will shift and there will be less and less exposed ice and ice core moraines will characterize this place more and more.”
While the debris acts as an insulator, slowing the rate of melting, it’s unknown how much ice is being preserved under that rubble in the first place.
“We don’t know what that trickle is,” Demuth admitted. “The whole eastern range of the Rockies is comprised of lots of ice-covered moraines. We’re trying to learn more about that process and phenomenon. Whether it’s significant contributor to our water supply – that’s another question.”
In addition to a five-year project launched in 2010 to measure the mass and volume of the Columbia Icefield, located about 90-minutes’ drive north on the Icefield Parkway on the Banff/Jasper national park boundary, Demuth and Bertollo are studying the feasibility of establishing a long-term monitoring site on the Yoho Glacier on the west side of the Wapta Icefield, from which the Peyto descends on the east. The two sites will be studied concurrently for at least a decade in preparation for the shift.
Nearing retirement, Munro is also establishing his own succession plan, sharing information with John Pomeroy, the Canmore-based head of the University of Saskatchewan’s hydrology department who will continue Munro’s work and compare it to his own non-glacier site on Marmot Creek in Kananaskis Country.
“Canada has a lot of cryosphere – the frozen part of the earth system,” Demuth said. “When the frozen stuff changes temperature or phase, those are indicators of changes in the earth’s energy balance. Canada has a unique role in the world to be the canary.”
