Global Ice Archive: Unlocking Climate Secrets in Lakewood’s Chilling Collection

In order to comprehend the current climate situation, researchers possess a wealth of solid, factual evidence in the form of ice cores that are extracted, arranged, and preserved at the National Ice Core Facility situated at the Denver Federal Center. Assistant Curator Richard Nunn describes these ice cores as “ancient time capsules.”

“They represent the most accurate record of our planet’s climate over the last 850,000 years,” he states.

“To grasp the current effects of human actions on the climate, the optimal approach is to truly understand the natural cycles our climate experiences, and ice cores provide that insight more effectively than any other means available on Earth.”

Researchers venture to some of the most severe and frigid regions on the globe to gather ice cores, typically drilled to depths of 200 to 300 meters, although some reach as deep as two miles.

Once obtained, the cores are sectioned into shorter pieces for manageable handling, meticulously packaged, and shifted to two large freezing units at the National Science Foundation Ice Core Facility in Lakewood, Colorado.

“Approximately 60 percent of our collection is derived from Antarctica, while about 20 percent comes from Greenland. We also possess a small assortment of cores collected from alpine glaciers worldwide,” says Nunn.

“We maintain the largest ice core collection globally, with nearly 25,000 meters of ice currently housed in our facility.”

Ellen Mahoney

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Rocky Mountain Community Radio

The facility offers an ice-cold environment for scientists to slice and obtain samples, which they later transport back to their institutions for examination. A second refrigeration zone, maintained at an even lower temperature, is utilized for the shelving and preservation of the ice cores.

While showcasing the technique of cutting an ice sample, Assistant Curator Richard Nunn likened the process to slicing through butter.

“There’s hardly any resistance. It’s not akin to slicing wood or metal or any other material. It’s delicate, so we must proceed with caution. But it slices very smoothly,” he indicates.

Eric Steig, a geochemist from the Earth and Space Sciences department at the University of Washington in Seattle, recently visited the National Science Foundation Ice Core Facility to take thousands of samples from an ice core extracted on Mount Waddington, the second-highest summit in British Columbia.

“Our current focus is on measuring the isotopic concentration of water, specifically the ratio of heavy to light oxygen in the H₂O. This data is significant because it provides an imperfect, yet still invaluable, metric of temperature. Essentially, we’re capturing a historical record of temperature changes over time,” states Steig.

When snowfall occurs in polar and glacial areas, it accumulates over time and compresses into extensive ice sheets. These ice sheets retain crucial information, such as trapped atmospheric gases, stable isotopes of water molecules, and ancient dust.

“We can procure an ice core that has records extending from contemporary times all the way back to 850,000 years ago. This allows us to reconstruct historical atmospheric conditions and how concentrations of greenhouse gases like carbon dioxide and methane have varied naturally over time, along with temperature fluctuations associated with glacial cycles,” explains Nunn.

Richard Nunn, who has been part of the Ice Core Facility since 2010, finds his work captivating yet challenging.

“The most demanding aspect is the necessity to work in extremely low temperatures. Even with appropriate gear, it can sometimes be uncomfortable. Some days are better than others. We operate in conditions ranging from -24 degrees Celsius to -40 degrees Celsius, depending on the specific area of the freezer,” he adds.

Although the Earth experiences natural cycles of cooling and warming, Nunn mentions that the ice cores unveil alarming details about the swiftly increasing greenhouse gas levels and their repercussions on climate change.

Climate Change Induced by Humans

“When we analyze the current situation, a more appropriate term would be ‘anthropogenic climate change,’ or ‘climate change induced by humans.’ This is our primary concern in contemporary times. The data shows that post-industrial revolution, CO2 levels have surged, currently reaching 425 parts per million,” he points out.

“We are significantly above any CO2 levels recorded throughout the entire ice core history. Moreover, the pace at which we have reached this point is at least ten times quicker than any event observed in the natural cycles. What we are witnessing now is more suitably referred to as ‘rapid climate change.’ We are compressing 2,000 years of change into mere centuries.”

In response to climate skeptics, Richard Nunn states:

“It may sound repetitive as I’ve articulated it numerous times, but one must examine the unfiltered science. If you could dedicate a little time to comprehend how our climate undergoes natural transformation, and then observe the current happenings, it becomes quite clear that we are significantly affecting it. The planet is, on average, warming.”

In addition to accommodating scientists from across the nation and globally, the ice core facility is also open to the public.

This content is supported by the National Science Foundation under Grant No. 2041950. Copyright 2024 Rocky Mountain Community Radio.

This report was disseminated via Rocky Mountain Community Radio, a coalition of public media outlets in Colorado, Wyoming, Utah, and New Mexico, including KUNC.