BUFFALO, N.Y. — Ancient sediment pulled from nearly a mile below the Greenland ice sheet — and later stored for roughly two decades at the University at Buffalo, whose researchers are still studying it today — is the focus of a new film.
“The Memory of Darkness, Light, and Ice” — now available to buy or rent digitally on sites like Amazon Prime and YouTube — details how the long-lost sediment has provided critical insights about when the giant ice sheet melted in the past, and perhaps when it will again.
Those findings have come from a team of researchers that include Elizabeth Thomas, PhD, associate professor in the UB Department of Earth Sciences. Led by the University of Vermont, the team has used the sediment to determine that the Greenland ice sheet was much smaller 400,000 years ago, when temperatures were similar to or slightly warmer and atmospheric carbon dioxide was at least a third less than it is today.
Thomas and her PhD student, John Michael Aguilar, both appear in the hour-long documentary. They were interviewed and filmed working with sediment samples in Thomas’ lab on North Campus in the summer of 2022.
“It’s exciting to have our research, especially on these precious and historical samples, featured in a film,” Thomas says. “Films like this provide stunning visuals and interesting story lines, and I hope that people find the science compelling enough to advocate for policies that reduce heat-trapping gases in the atmosphere.”
The film has won awards at multiple science and environmental film festivals and was screened at the U.S. Capitol as part of a Sustainable Energy and Environment Coalition Task Force briefing. It aims to serve as both a scientific revelation and a call for urgent climate action.
It is directed by internationally acclaimed scientist-filmmaker Kathy Kasic, who was a co-principal investigator on the National Science Foundation grant that supported Thomas and the rest of the team’s research.
“Kathy and her team have been an integral part of the project from Day 1,” Thomas says. “Kathy has experience making documentaries for science teams, so she was an obvious person to lead this effort.”
Sediment’s connection to UB
The sediment’s backstory — how it was recovered after thousands of years buried under ice and later rediscovered after decades in storage — is deeply intertwined with UB.
The U.S. Army scientists who pulled it from beneath the ice in the 1960s were led by Chester “Chet” Langway, who would later serve as chair of the geology department at UB. Langway’s team was at Camp Century military base as part of a failed attempt to hide nuclear missiles under the ice sheet, but they did succeed at drilling what would be the world’s first complete deep ice core.
When they pulled up the ice core from 4,560 feet below, there was an 11-foot tube of dirt stuck to the bottom.
The sediment came with Langway when he joined UB in 1975. It remained in the university’s Central Ice Core Storage Facility and Information Exchange, then the nation’s leading ice core laboratory, until Langway’s retirement in the mid-1990s.
It then sat largely forgotten for another two-plus decades at the University of Copenhagen in Denmark until a serendipitous freezer cleanout in 2018.
What the sediment tells us about ice sheet’s past — and future
When scientists looked at the sediment under a microscope, they were stunned to find twigs and leaves instead of just sand and rock. That suggested that the area had been free of ice in the recent geologic past — and that a vegetated landscape stood where a mile-deep ice sheet stands today.
Researchers have since determined the sediment was deposited by flowing water in an ice-free environment during a moderate warming period somewhere between 424,000 to 374,000 years ago.
This confirms a troubling understanding that the Greenland Ice Sheet has melted dramatically during recent warm periods in Earth’s history, and could again if temperatures continue on their current pace.
Approximately 23 feet of sea level rise is tied up in Greenland’s ice, putting every coastal region in the world at risk.
“We know that Greenland is warming even faster than the rest of the world, and the ice sheet is shrinking rapidly,” Thomas says. “This kind of research helps place bounds on what we might expect to happen in the near — and distant — future as heat-trapping gases remain at high concentrations in the atmosphere.”
UB’s ice sheet research featured in new documentary first appeared on UB National News.
