By Allison Kubo
New research published in the Proceedings of the National Academy of Sciences shows that the Greenland ice sheet had melted and reformed at least once in the past 1.1 Ma. The team found fossilized plants buried under 1 million years of snow at the base of the Camp Century Ice Core. The long core takes up the layers of snow in the Greenland ice sheet.
The deeper the core, the older the ice, and at its deepest point the Greenland ice sheet measures around 3 km. Finding dirt and plant matter in the core under layers of ice suggests that it was once covered with plants and maybe even trees. Researchers used cosmogenic isotopes, atoms that only form when radiation from space and the sun interact with dirt, to show that they have melted at least once in the past 1 million years. Though it seems like a long time, 1 million years is a wink for geologists. This research shows that Greenland could almost completely melt and refreeze in a very short time. It shows that climate change is a threat to humans in our lives and that the Greenland ice sheet is very sensitive to climate change.
This isn’t the first time the Camp Century Ice Core has made important scientific or even social discoveries. The saga that was needed to sustain this research includes secret Cold War missions, abandoned bases, modular nuclear reactors, lost data, and a 4560-foot sample of Earth’s past.
It was drilled from 1963 to 1966 and was one of the first long ice cores used to model climate and view geological history. Camp Century, just 800 miles from the North Pole, has been built into the ice, including a barracks, theater, and hair salon, all powered by a portable nuclear reactor. But climate science at Camp Century also hid more worrying motives. The Iceworm project, released in 1996, was located in Camp Century and was intended to station 600 nuclear warheads under the ice. They soon learned that the ice was too unstable to sustain the base, let alone fire missiles. The US Army left the base and its debris to be reclaimed from the ice. Although originally intended as a cover, the ice core became the subject of extensive work in climate research, climatology, and even volcanology, as it recorded ashes from large eruptions. However, as new cores were drilled, interest in Camp Century waned and it was shipped from New Hampshire to Buffalo and eventually Copenhagen in the 1990s. The boxes and boxes of ice were forgotten in the freezer in Denmark until 2018. We continue to see the legacy of the Camp Core ice core with the latest research released by the University of Vermont.