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Canadian researchers pull old ice core from Mount Logan Geological Survey of Canada wraps up three seasons of drilling at Prospector-Russell Col, collecting ice samples to show how climate has changed over time by The Associated Press
An ice core removed from Canada’s highest mountain may date back to the last Ice Age, according to the team that drilled it.
The Geological Survey of Canada recently wrapped up its third and final season of drilling at Prospector-Russell Col, at an altitude of 17,388 feet, on Mount Logan in the Yukon Territory.
Mount Logan, at 19,550 feet, is second only to Mount McKinley in North America. It’s part of the Wrangell-St. Elias Mountains and is located about 20 miles east of the Southeast Alaska-Canada border.
In 1980, a research team drilled an ice core on Mount Logan that dated back 400 years. Such ice samples can act as a sort of archive in showing how the climate has changed over time.
“What we were trying to do here is extend that record by drilling further, drilling deeper, back to bedrock,” glaciologist Christian Zdanowicz told the Whitehorse Star. “We didn’t drill in the same location so it was different, but close to the original site. The objective of the whole program is to try to obtain what we call a proxy record of climate.” Samples from last ice age A proxy record has information, but unlike tree rings which shows year-to-year information, as the layers of ice get thinner, the information becomes more spread out.
Zdanowicz estimated the ice samples his crew retrieved go back some 12,000 years to the last ice age.
Until the 1980 effort and from then until now, there hasn’t been any extensive proxy records from the North Pacific region.
Zdanowicz said most of the work in the northern hemisphere has been concentrated around the north Atlantic.
“You want to have sort of a network of records that you can compare to one another,” Zdanowicz said. “And we know that the north Pacific is very dynamic, climatically. We know it plays a very important role in regulating the climate of the North.”
While the drilling took three seasons — each running from April to mid-June — the longest part of the work will be the research over the next few years. Samples from the ice core will be sent to various labs to assess different aspects of the sample.
Ice can measure direct climate information such as past temperature, snow accumulation and wind speed. Atmospheric information can also be measured.
With about 10 people working on the site this year, it took less than a week to drill down to the bedrock at 623 feet. This is a continuation of last year’s efforts when the six-person team drilled down to 564 feet.
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