Near the frozen, wind-buffeted summit of Mount Logan, Canada’s highest peak, lie some of the most ancient nonpolar ice deposits anywhere in the world. The glacial ice there—which, although unconfirmed yet, could be as much as 30,000 years old—has been around since the end of the last ice age, and is therefore a treasure trove for scientists looking to understand Earth’s climate past. Hidden away in the snow-covered Saint Elias Mountains, in remote Yukon, Mt Logan is treacherous to reach for adept climbers, let alone gear-toting scientists. Still, that doesn’t deter Alison Criscitiello. The American glaciologist and explorer has traveled to both poles and numerous high mountains in the search of ancient ice, in the hope of better illuminating the risks of climate change.
“There aren't that many things that we can go to on the planet that tell us about long-term climate in the past. Ice cores are one,” Criscitiello explains in the new episode of Planet Pioneers, WIRED’s ongoing video series in partnership with the Rolex Perpetual Planet Initiative.
Ice might seem simple, but it can provide a remarkably detailed look into the past. “To me one of the most intriguing things has always been that when you melt the ice, you don't just have the liquid chemistry of the water, which is telling you about various parts of the environment in the past, but there's the little bubbles of ancient atmosphere trapped in the ice as well,” Criscitiello says. “And so, we can look at gases, we can look at what was actually the composition of the atmosphere in the past.” Traces of carbon, for example, help indicate the frequency and dates of long-ago wildfires. “So, understanding over longer timescales, for example, wildfire history in the Pacific Northwest, can help us to project future wildfire behavior.”
While climate scientists in the polar regions have found ice that dates back hundreds of millennia, high-altitude ice is younger—and yet crucial in understanding the impact of climate change in other parts of the world, particularly which fresh water glaciers provide drinking water.
Criscitiello is used to operating in vertiginous places. As director of the Canadian Ice Core Lab at the University of Alberta, she is a former US climbing ranger and mountain guide, and has led expeditions in the Himalayas and to some of the world's highest peaks. She has long been drawn to heights. “I did start climbing ice at a very young age and adventuring in the coldest places I could get to from where I grew up.”
But the Mount Logan expedition marked her most extreme research project yet. In May 2022, Criscitiello and six teammates set out to Mount Logan to attempt to draw ice cores from the glaciers near the summit. Criscitiello had already climbed the peak a year earlier to conduct radar surveys of the site, but this was another level of logistical and physical challenge.
“The drill site was at 18,000 ft,” she explains. “We can’t just fly to 18,000 ft, you get mountain sickness … so I treat projects like this as a sort of mountaineering expedition. We fly in at around 10,000 ft, and have to climb there.”
Climbing at that height isn’t easy even for practiced mountaineers. But Criscitiello’s team had the additional challenges of hiking up weeks’ worth of supplies, and a 900-lb custom-made drill that had to be flown in by helicopter. Reaching the drill site took the seven-person team 10 days; although all recovered, several of the team didn’t make it to the site after developing high-altitude medical issues. “We started as seven and we ended as four,” Criscitiello says.
Once camp was set up, the remaining team—which included Dominic Winski, Rebecca Haspel, Bradley Markle, and Etienne Gros—drilled for 14-hour days, in extreme conditions. The ice cores, collected in meter-long chunks, are gathered in insulated sample tubes, which are later flown out by helicopter to a dedicated storage facility. “The things that make it a really good place to drill for ice make it an absolutely horrendous place to be,” she says. But it was worth it. Under Criscitiello’s leadership, the team collected a core from 327 m deep, a record at such a high altitude. That core is thought to date back 30,000 years, the oldest nonpolar ice core in the world.
Like her previous field work, the Mount Logan expedition was supported by the Rolex Perpetual Planet Initiative and National Geographic. “It is by far the biggest and most complex project I've led to date. And there's zero chance that it could have happened without that support,” Criscitiello says.
In addition to analyzing the ice and sharing her team’s findings, Criscitiello is committed to communicating the importance of glaciologists’ work and the risks that we face by climate change. “There’s a storytelling component here, and a platform to communicate science that I’ve never had,” she says. “And it’s unbelievably powerful.”
To find out more about Rolex and its Perpetual Planet Initiative, visit rolex.org, and explore our Planet Pioneers partnership page here.
