Researcher retrieving an ice core in the new facility at the Niels Bohr Institute
Dear Commons Community,
Hakai Magazine had a featured article earlier this week entitled, “ The Coolest Library on Earth” that reports on an ice storage facility at the Niels Bohr Institute at the University of Copenhagen. The researchers at the Institute are world leaders in climate research based on ice cores. Ice core research at the institute dates back slightly more than 50 years and takes its starting point in the research performed by one Professor Willi Dansgaard, in 1967-69. The new central ice “library’ was opened in 2020. Here is an excerpt from the Hakai article.
“In a narrow aisle of shelves packed with cardboard boxes, Jørgen Peder Steffensen grins like a mischievous child unwrapping a holiday present as he pulls out a plastic-wrapped hunk of ice from a box marked Keep Frozen.
The bag of ice contains the transition from 1 BCE to 1 CE, he says. “That means we have the real Christmas snow.”
This piece of ice, a bit longer than his arm, doesn’t visibly look different from modern ice. Yet bubbles trapped in it preserve the chemistry of the air in Greenland from more than two millennia ago. “But we can’t find any traces of reindeer, or magical dust,” Steffensen quips.
In this freezer facility in Denmark, Steffensen’s team at the Niels Bohr Institute at the University of Copenhagen stores some 40,000 segments of ice cores, long cylinders of ice from polar regions that preserve the history of past climate. Beyond cataloging frozen treasures, Steffensen collaborates on research that chisels out historical secrets hidden in ice, and runs logistics for an international drilling project in Greenland to retrieve even more deep-core samples.
Copenhagen is one of several places in the world where pieces of ice cores drilled from our planet’s extremities are kept safely cold. Other large research freezers are located in the United States, Australia, France, Italy, Germany, Russia, and Japan. According to Steffensen, Copenhagen has the most samples from the world’s deepest cores, amounting to 15.5 kilometers of ice. That’s about the distance from Steffensen’s laboratory in central Copenhagen to this unassuming yellow-tiled warehouse in an industrial park, where the ice archive has been housed since 2019. Both the lab and the freezer spaces are temporary, awaiting the completion of a massive construction project for a new university facility. The archive also keeps an additional five kilometers of ice from shorter cores drilled in Greenland, Antarctica, Iceland, Patagonia, and a glacier in a Slovakian cave. Some ice samples came from initiatives with strong Danish involvement, while others came from researchers abroad looking for a chilled home.
Ice cores serve as important historical records for scientists interested in how our planet’s climate has changed, whether in the distant past or more recently. Like tree rings, layers of snow that fell and formed these cores can be counted and correlated to years in the past. In a core drilled from a place that sees minimal melting, “all those annual layers of snowfall are just in one undisturbed sequence back in time,” Steffensen says. “The deeper you go, the farther back in time you go.”
But a single core likely doesn’t have a continuously pristine record; the timeline traced by snowfall layers may have been disrupted by localized weather events millennia ago. That’s why it’s important to have multiple core samples from the same time period extracted from different locations—to compare results and bolster scientific conclusions. Greenland and Antarctica both host multiple international ice drilling sites. “You actually need more than one ice core record to combine in order to get a climate signal,” says Maria Hörhold, a glaciologist at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, who led a recent study on Greenland’s record temperatures.
As Copenhagen’s ice core curator, Steffensen, who goes by J. P., describes his job as akin to a librarian’s, presiding over the “volumes” of ice that contain the secrets of Earth’s climate history. But when researchers want to borrow a sample, Steffensen can’t simply scan a barcode. Members of international collaborations who drilled the core in question have steering committees that grant access and determine the amount that can be cut. Steffensen also writes up an opinion on how much of the core can be spared, with an eye toward preserving the continuity of the historical ice record.
Unlike a book, ice that goes out for study will never come back. Investigations into the history of atmospheric chemistry, temperature records, and ancient DNA are all ongoing, but they require melting or vaporizing to get to the goods.
This windowless library’s floor-to-ceiling shelves safeguard about 1,900 cardboard boxes and crates of ice.”
Pretty “cool”!
Tony