Ancient ice samples from highest mountain in Canada may reveal past climate secrets

Alison Criscitiello, National Geographic Society Explorer and director of the Canadian Ice Core Lab at the University of Alberta, said the ice could be 30,000 years old. 

The ice, now in freezers at the University of Alberta, could be 30,000 years old

Alison Criscitiello shows off the boxes of ice core samples collected from Mount Logan, Yukon. She believes the ice cores could be 30,000 years old. (Anne Myers)

Ice core samples from Canada's highest mountain, now in storage at the University of Alberta, may provide scientists with answers about Earth's climate thousands of years ago.

The samples, from an ice core drilled 327 metres deep on Mount Logan, Yukon, are in 35 cardboard boxes, each about the size of a mini fridge.

The boxes arrived in Edmonton last week and are now in freezer storage at the U of A's department of Earth and Atmospheric Sciences.

Alison Criscitiello, a National Geographic Society Explorer and director of the Canadian Ice Core Lab at the U of A, said the ice could be 30,000 years old, "which is very unusual for ice outside the polar regions.

"It's very hard to find a place like this that hasn't been impacted by melt," Criscitiello told CBC's Edmonton AM on Thursday.

"There's just so much information locked up in this ice core.

"It's endless. We're going to measure tens and tens of different elements and major ions and species in this core, all giving us different clues into past climate."

Criscitiello said she's excited to start working on the ice core samples, which were collected after 11 days of drilling on the almost 6,000 metre-tall mountain.

"The ice seems so pure that it's almost blue," she said. 

Getting to this point has been two years in the making. In May 2021, Criscitiello climbed the mountain to lay groundwork for the drilling.

Then, in the first week of May this year, she climbed the mountain again for the actual drill work. 

The high altitude, extreme temperatures and wind made the entire process "very, very difficult," she said.

"It was a logistical nightmare."

Drilling ancient ice on Canada’s tallest mountain

1 year ago
Duration 1:31
University of Alberta researchers scaled Canada’s tallest mountain to extract ice cores that hold secrets about millenia past.

She and her colleagues got supplies and equipment, including the drill, sent to the site via helicopter. It took the helicopter several flights to get Criscitiello and her team everything they needed, she said.

The new ice core samples will replace ones lost due to a freezer malfunction in 2017.

Criscitiello said drilling on Logan this year was always the plan because the samples lost in 2017 — collected from the mountain in 2002 — were taken after drilling to a depth of 181 metres. Those samples were 16,000 years old. 

Bradley Markle, an assistant professor of geological sciences at the University of Colorado Boulder, holds an ice core retrieved from Mount Logan. Markle was on the team with Alison Criscitiello that climbed Canada's tallest mountain last month to drill for ice cores. (Alison Criscitiello/University of Alberta)

Criscitiello said scientists knew even older non-Arctic ice existed deeper into the mountain. The melting incident just fast-tracked the re-drilling process, she said.

Now that the ice samples are in her care, she and her colleagues have a long list of data they plan to collect, including forest fire history, volcanic ash fallout and temperatures in the past.


Kashmala Fida Mohatarem is a reporter and associate producer with CBC Edmonton.