Scientists Seek to Collect Ice Core Samples Before Glaciers and Ice Sheets Melt

Yves here. As Covid-19 stories and Festival of Kamala fade a bit, the latest phase of long-running trends comes back into focus. This piece ties into other reports this week, of the melting of the Greenland ice sheet having hit the point of no return, and then the death of the revered glaciologist “Koni” Steffen.

I have to confess I had no idea how much planning it takes to perform an ice core study.

By Kristen Pope, an Idaho-based freelance writer who frequently covers science and conservation-related topics. Originally published at Yale Climate Connections

Lonnie Thompson of Ohio State on 2019 Huascaran expedition (Photo credit: Todd Johnston)
Scientists are rushing to sample the cores of rapidly melting glaciers and ice sheets, hoping to preserve a rich record of changes in Earth’s atmosphere and biosphere over the eons. Ice cores contain evidence of trace elements, gas bubbles, dust, pollen, even viruses and bacteria that can be traced back in time to yield vivid images of Earth’s history and prehistory for those who learn to read them.

“Just about anything that’s in the atmosphere gets recorded in the ice,” says Lonnie Thompson, glaciologist and paleoclimatologist at Ohio State University. Thompson has led more than 60 expeditions to sample ice cores from glaciers and ice sheets in a career spanning over four decades. Some sites he has drilled – including glaciers on Mount Kilimanjaro and in Indonesia – have already melted and vanished. Byrd Polar and Climate Research Center at Ohio State holds thousands of meters of preserved ice cores, safely stored in sub-zero freezers. Studying the ice has already yielded secrets of Earth’s past related to volcanic activity, changing vegetation and even human manufacturing techniques.

Hoping to add to the collection, Thompson and other researchers are racing to obtain and preserve ice core samples from remote and, for now at least, still icy places around the globe. They hope to find clues that can help learn about that past, and scientists can use ice core samples and the data they contain to test and verify climate change models to better predict the future.

They also hope that preserving the cores will provide future scientists with samples that they can analyze with technology that may not even exist yet. Thompson can envision a day when samples he has collected now can allow future scientists to answer questions people have not yet even thought to ask.

As glaciers and ice sheets form and layers of snow accumulate, the ice slowly spreads out, compressing the layers and thinning over time. Those layers tell stories about the past, much like rings on a tree record signs of fires, drought years, and seasons of ample precipitation. Similarly, the dust in ice core samples contains information about volcanic eruptions and gives clues about droughts, pollen records, and crop and vegetation changes. Scientists studying ice core samples can even learn how past plagues changed society and culture. Researchers found that ice samples dating back to the plague of the 1300s contained less leadthan would otherwise be expected, indicating a temporary reduction in smelting and industry during the time.

Thompson and some other scientists believe the COVID-19 pandemic may be observable in future ice core samples. Quarantines and restricted movement led to a reduction in pollution as people stayed home and industry slowed. Sulfur dioxide, nitrogen dioxide, and other emissions were reduced in many areas, if only temporarily. Future glaciologists may be able to detect lower levels of nitrates and sulfates in ice, providing a unique snapshot in time.

Facing Extreme Challenges

Studying ice cores isn’t for the faint of heart. Researchers must travel to Earth’s most isolated regions to collect samples, from Greenland and Antarctica to the slopes of tropical mountains with rapidly melting glaciers. It is always challenging logistically to get a team of researchers to where the ice is, and ice coring work typically occurs in extreme conditions.

“It’s a truly bizarre and wonderful experience,” said Richard Alley, Penn State glaciologist and geologist. In over 40 years studying ice, Alley has spent a lot of time braving extreme weather in polar regions. He has been rewarded with otherworldly scenes while collecting samples and data.

“The central part of an ice sheet is pretty subtle. There are snow drifts, and then there’s the ice sheet and there’s nothing else – it’s just flat. You go to a place where often the sun never sets – it starts going around in circles – and it’s snow, and then it’s snow, and it’s snow and that’s all it is.”

Working with fragile scientific equipment in the most remote stretches of the globe leads to its own set of challenges. Researchers have to be resilient, flexible, and creative.

“The field is hard,” Alley says. “Drilling a two-mile-long core of ice is hard. Things always are going to go wrong. The people who do the drilling, the science team, and the whole group just show amazing levels of resilience and innovation to try to get these things built.” He notes they return to their homes and laboratories with the data and ice cores they came for, but he says, “it doesn’t always start working the way it was supposed to.”

Alley says samples from his projects are typically shipped to the National Ice Core Laboratory in Lakewood, Colorado. There, researchers carefully slice the cores, providing samples to various teams who perform analyses of everything from dust to isotopes. They also are able to melt a sample from the inner core – a location where it could not have been contaminated by touching anything – and they carefully analyze the stream of meltwater.

Alley’s work mainly focuses on the poles – both the Arctic and Antarctic – and he finds some advantages to those research locations, including often being able to fly directly to the research site via ski-equipped aircraft. However, he also points out the necessity of assessing ice samples in other parts of the world. “The poles are easier in a lot of ways – there’s no meltwater, it’s cold, and you can get really, really nice records,” he says. “But it’s really valuable to be able to get closer to where people are.”

Even with the Best-Laid Plans, Surprises Are Common

While conducting research in largely uninhabited polar regions presents an array of challenges, so too does working in the tropics.

Researchers spend years preparing for an ice core drilling project, and Thompson says it can take four or five years of planning and preparation before it’s time to head to a field location to collect data. During this time, he says, researchers work on putting a capable team together, sourcing all the equipment they will need, embarking on a massive logistics effort, and working with national and local governments as well as local people. But despite their preparatory efforts, trips don’t always go as planned.

In 2019, Thompson’s team of researchers was on the Peruvian mountain of Huascarán when they received word they needed to leave the mountain within 12 hours because locals did not want them there. With teams spread out over the mountain, Thompson explained that the time frame was impossible to meet and negotiated for two days to extract his team. Leaving the mountain in a hurry, the team was forced to leave ice cores and equipment behind, hoping they could retrieve them later.

Thompson met with local people to learn more about their concerns. He learned local residents mistakenly believed his team was planning on developing a gold mine and extracting resources. They were concerned about potential pollution, and when they heard about the ice drilling project, they were upset foreigners were taking ice and removing it from Peru. He says the locals were also concerned that Peru’s president came to visit the drilling site via helicopter, bypassing the local villages and not listening to peoples’ concerns about an array of issues – including those unrelated to the scientific research.

Ultimately, the discussions resulted in Thompson’s receiving permission to remove his team’s equipment and the ice cores from the mountain with the assistance of an Mi-17 helicopter from the Peruvian government.

On a 2010 expedition to a mountain in New Guinea, Thompson’s team was planning to drill an ice core from a glacier on a rainforest mountain. A warming world meant the glacier was in imminent peril and, if they didn’t obtain samples soon, they might never have the chance. While they received governmental permits and authorization, they soon learned when they arrived in the area that tribal leaders were not on board with the project. Thompson engaged in discussions with people, hoping to find a solution.

“In the religion of this tribe the arms and legs of their god are the mountains and the valleys, and the head of the god is the glacier,” Thompson explains. “And, in their words, we were drilling into the skull of their god to steal their memories. And I said, that’s exactly what we’re doing – we are trying to capture those memories before they disappear because these glaciers will disappear.”

He recalls how tribal members discussed the situation, with elders saying the glaciers would always be there and younger members explaining the glaciers were actually retreating rapidly.

By the end of the meeting, the tribes granted permission to continue with the project, drilling the ice cores and bringing them back to Ohio to keep them – and the knowledge they contain – safe for future generations.

Preserving Ice-Locked Records Before They Disappear Forever

Part of the reason researchers believe it is so important to preserve ice core samples while they still exist is so future scientists can one day use technologies perhaps not even imagined today to further analyze them.

“The beauty of ice is that it records everything that is in the environment,” Thompson says. “Unfortunately in today’s world, and in the future, many of these archives are going to disappear and we will lose that history.”

Editor’s Note:  Considered among the very top tier of the world’s most respected glaciologists, Thompson and Alley share some common bonds: Each is a Member of the National Academy of Sciences, and each has been an author and/or subject of public broadcasting documentaries and books. Thompson is a 2005 winner of the National Medal of Science, awarded by the President of the United States. Alley, widely recognized as a highly innovative and charismatic climate science communicator, is the force behind the PBS documentary “Earth: The Operators’ Manual” and the companion book.

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  1. periol

    I appreciate the scientific knowledge we gain from the ice, and these ice samples specifically, but…

    …there is something a little strange about teams of western scientists flying around in planes and helicopters chasing the vanishing ice. Ice that is vanishing because humans have been heating the planet with our fossil fuel usage for a few hundred years. I guess these scientists consider their fossil fuel usage to be justified. I’m not sure I would agree.

    Certainly, the villagers in Peru weren’t too thrilled with rich white men coming for the ice, and then getting helicoptered out. The article doesn’t go into it, but you can imagine them saying “who cares about ice when we barely have enough food?” The president shows up for the ice, but skips the people? Wow.

    1. occasional anonymous

      Do you seriously think the amount of carbon emitted by the planes and helicopters used by scientists has any meaningful impact on the climate? Them not using them (and thus not getting any core samples) would be nothing more than an exercise in virtue signaling.

      1. periol

        “nothing more than an exercise in virtue signaling”

        no one will stop using until we hit rock bottom. until then, whatever the reason is, it will always be good enough to justify using again.

        refusing to contribute to the destruction of our planet is virtue signalling – dang. this is why i think our civ goes until it collapses. no turning this ship around.

  2. Plague Species

    Great idea, but they should be careful not to fall through an ice sheet. They can put the samples in Gates seed vault for posterity when the Mecha stumble upon it in a million years during one of their archaeological expeditions.

  3. The Rev Kev

    In a way this is like taking the DNA of animals on the verge of extinction. Once it is gone, it is gone. Mentioned in a comment some time ago how I saw a TV doco where a scientist was discussing how the glaciers were on the retreat. In the middle of a rocky slope, he said that when he was there a decade ago, the ice was I think about 60 feet above where they stood and that this was where they did their drilling. He then pointed to a small hole near their feet and said that this was the point that the drill finished going through the ice and hit rock. That was an incredible amount of ice that disappeared so I assume that the ice cores that he took are the only thing left of the glacier that stood on that spot.

  4. Denis Drew

    Earth’s atmospheric temperature is already high enough to melt the permafrost (part of year freezing, part melting, more melting than freezing). The permafrost (I’m not exactly sure what that is) reportedly contains twice as much carbon as there is in the atmosphere now (may not be all in gas form but believe will all end up in gas form eventually: one and a half trillion tons to add to 750 billion tons now). The more it melts, the more carbon dioxide is released, the hotter it gets, the more it melts, etc.: more than enough to eventually turn the earth into a pole to pole swamp — the normal condition of the earth for the majority of the last 500 million years (see video). Indisputable — without any additional human help.

    1. Plague Species

      Yep, and the permafrost also, in all probability, contains many frozen, soon to thaw, diseases for which contemporary human has no immunity. If we think COVID-19 is bad, we ain’t seen nothing yet. Soon enough, we’re going to be dodging so many calamitous existential bullets, we’re going to feel like those poor sap soldiers “storming” the beaches at Normandy. Flesh to the slaughter. A sizable percentage was going to perish and surely the meat sacks knew they were marching straight into their sure death and many were. If you survived, it was pure luck. The difference between the metaphor and what it’s meant to represent is, America won the war ultimately despite the sacrificial carnage at Normandy, only for humanity to perish at a later date from the despoiling of the environment that enabled its meteoric rise where war played its part in the despoiling. If we widen our perspective, all those who perished on the beach at Normandy died in vain.

    2. flora

      yes. releasing methane from perma frost and from methane crystals in the ocean’s floor. methane is much more powerful than CO2 as a greenhouse gas but shorter lived before degrading into CO2.*

      In those short decades, methane warms the planet by 86 times as much as CO2, according to the Intergovernmental Panel on Climate Change.

      As far as the Greenland ice sheets and glaciers melting away raising sea levels being a worry, even more worrying for the British Isles and western Europe is disruption to the North Atlantic Current. Imagine 50-100 years from now, without the moderating effect of the North Atlantic Current, polar winters in London and 100 F degree summers in Paris and Oslo.

    3. John Farnham

      You would not be the only person not to know what permafrost is. A British Army translation of Russian manual on building on permafrost caused a complete kludge of building installations on the Pine Tree Line when it was classified. Against whom one might ask.
      As far as ‘global warming’ goes ( yes, it is a thing – and there is a ‘but’ ) one would do well to remember the Greenland Icecap is uncovering remnants of installations and aircraft from WW II. Under ice vulcanism is bound to have dramatic effects on meltwater – as it would in the Antarctic. Accumulation is therefore hardly something to discount offhand. Sometimes the scoffers may have intel.

  5. polecat

    Adaptation, folks … that and mitigation where possible. But to stop or reverse what are chaotic, and turbulent systems (both atmospheric AND oceanic) is hubristic folly in the extreme. Things change – whether we humans contribute to such changes, or not! We’re still working our way through an interglacial episode.

    But we, as ‘modern’ contemporary humans, think things should remain static … forever! … because we deem it so.

  6. witters

    You are not using adaptation as did Darwin. Adaptation is what natural selection leaves after all the deaths, and only if there is anything left. It is not a prescription – and such a prescription is not an appeal to natural selection.

  7. viability4us

    The assumption that fossil fuel burning is the sole reason for disappearing glaciers is very shortsighted. The two biggest heat sources for planet earth are the thermonuclear reactions on our sun and within the mantel of the earth, as seen coming out of volcanoes when they erupt. Likewise, the variations of the orbits of not only the earth around our sun but the intersection of other bodies entering our solar system and disrupting what many think are stable orbiting patterns. There are so many things about our own galaxy that we don’t know yet, to assume that it is mankind, running around on the planet like some ant colony, affecting the planet’s climate and atmosphere is rather self-centered in my opinion. Maybe it is not what man is doing at all!
    The planet was here before mankind arrived and will be here long after our species is gone, much like many other species that have since vanished from Earth. Far more attention should be put on the astrological aspects of what affects and changes orbits within our solar system and events such as the Carrington event, than what mankind is doing to cause our glaciers to melt.
    Reduce Mankind’s footprint; cleanup plastics in the oceans and nuclear waste leaking from buried barrels 60 years ago, but don’t assume that all environmental and climatic woes of this planet are due to mankind, because you might just be wrong!

    1. Thomas P

      We ‘might’ be wrong, but available science support that at the moment humans are the main driver of change in climate. I prefer to go with the science.

      We already know well how the orbits of planets change in the solar system, at least on relevant timescales. What happens in a billion years may be uncertain.

      1. Ashburn

        Yes, the speed of the change is very relevant. Orbital changes take place over eons, I suspect, not decades. Climate change presents us with a more immediate problem.

        It reminds me of the joke about the dozing student in an astronomy class. When the professor announced that the Earth’s sun would expire in 8 billion years. The student suddenly sat bolt upright and said “What, what did you just say?” And the professor mildly replied “I said our sun would expire in 8 billion years.” “Oh,” said the student, relaxing a bit, “I thought you said 8 million.”

    2. Larry Y

      Wait, you’re arguing for the precautionary principle except for climate.

      Also, being deliberately ignorant about the role of greenhouse gasses (see extreme example of Venus, which is hotter than Mercury)… you’re one who’s more likely to be wrong!

  8. Scott1

    God as evidence. God as memories. God is in Ohio in the body of frozen ice cores.
    It’s an interesting god like that.
    & Scientists as the tribe of memory collectors. Archeologists of ice.
    Not really.

    1. periol

      There is something fascinating about the ice vanishing just as soon as we figured out it is a historical database and learned how to read it.

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