By Chelsea Zhao, Dilpreet Raju and Ilana Wolchinsky,
Dec. 21, 2022 – As the Earth warms, researchers at the Ice and Climate Exploration Research Center (PSICE) at Pennsylvania State University are interested in how we can expect glaciers, those dense bodies of ice that move under their own weight, to react to a drastically changing environment.
Extreme hurricanes and floods and increasing wildfires and drought make the impact of climate change increasingly obvious, but what happens to glaciers and ice sheets is important for the future of so many coastal cities that lie in potentially devastating floodplains.
Veteran geoscientist Richard Alley of Penn State University revealed a bleak future during the annual Comer Climate Conference this fall, one where a changing climate will affect the Earth and all of its inhabitants, not just humans, at a systemic level. The conference draws scientists from across the world sharing their latest findings and documenting the urgent need to address climate change.
Alley said to study climate science is to steep your way into worry and anxiety about the future.
But it presents solutions to those very worries as well.
“I suspect the students need a sign over the door that says, ‘We are the ark,’” Alley said. “We’re going to get through this by preserving (various) species so we can get them back out, ’cause some of them are in such deep trouble now and they’re going to need help.”
By 2100, projected global sea-level rise could be slowed to a half meter lower than prior projections, but only if global temperature increase is kept at 1.5 degrees Celsius instead of 2 degrees Celsius, according to estimates by the Intergovernmental Panel on Climate Change.
Alley considers the projection a modest estimate and seeks, along with his research group, to estimate a worst-case scenario resulting from no climate action.
“We can hope, but I think the biggest thing is to limit CO2 (carbon dioxide), and then as much collateral damage (as possible),” he said.
CO2 levels drive global warming from fossil fuel emissions, and many scientists calculate that increasing levels over the past decades are already rolling 2 degrees Celsius of temperature rise into the atmosphere. Alley said that carbon dioxide spells devastating damage for lots of
organisms that live in seawater even before those rising tides can impact humans. Marine life is the canary in the cage for the threat to other life.
Organisms like coral are subjected to toxic underwater levels of carbon dioxide, and the effort to cultivate nature-resiliency and human-resiliency can only go so far as long as carbon dioxide level continues to rise.
“Too much CO2 too fast looks like a really bad prescription for coral reefs,” he said. “It’s very clear that the more CO2 we put in the air, the harder the task we’re setting to keep the reefs.”
Pollution remains a prime catalyst for deadly disease in coral reefs, however.
Over the past decade, the reefs have seen a visible change from what they once were. No longer filled with bright colors and thousands of fish, the dying reefs are now dull, muted colors.
“If you’re dumping poisons on the reef, it dies faster, whether that’s your sewage outflow or whether that’s your sunscreen,” Alley said. “Keeping those things off the reef is good.”
Alley has studied the great ice sheets to predict future climate and sea level change. He participated in the UN Intergovernmental Panel on Climate Change and was the co-recipient of the 2007 Nobel Peace Prize the IPCC received along with former Vice President Al Gore. Alley was also the first recipient of the Stephen Schneider Award for climate communication.
Sierra Melton, a geosciences Ph.D. student of Alley’s, currently focuses her studies on one of the largest glaciers in Greenland, Helheim Glacier. The glacier drains from the Greenland ice sheet straight into a fjord and, upon touching the water, breaks into icebergs. Melton is studying the complex hydrology behind the phenomenon as it is not totally understood by researchers yet.
“With more melting and warming, and glacier collapse, studying Helheim is kind of one way to look into the future where these glaciers might look like,” Melton said.
“It’s really a very interesting glacier because there’s a lot of meltwater, both on the glacier and draining from up the glacier,” she said.
Climate change research was the only major avenue Melton ever considered for a career path, long before she started her work on large-scale glaciology projects.
“I don’t know exactly why, but I was just always concerned about it,” Melton said. “Even for one of my birthdays in elementary school, I asked for donations to the World Wildlife Fund to save the polar bears. So yeah, so I guess I’ve always been concerned about climate change.
“I am very concerned about what climate change is going to do for our future. And that’s why I’ve gotten into this work” she said. “And I think it does motivate me more than it makes me anxious.”
Photo at Top:
Sierra Melton, Ph.D. candidate Sierra Melton at Penn State concentrated her focus on glaciology.(Byron Parizek/Penn State)
Crystal Rao, a geoscience graduate student at Princeton University, bases her research on the environmental changes and climate impacts on the species in clues from nitrogen isotopes in fossils.
Rao uses the ratio of two common forms of nitrogen as a standard, and compares it with the nitrogen inside the tooth of the megalodon shark. She has reconstructed a picture of when and where megalodon sharks topped the food chain in Arctic waters. Rao said this fierce predator could “basically eat anything in the ocean”.
Yet this 50-foot long shark, went extinct some 3.5 million years ago. Rao said the food source the sharks relied on to fuel their massive bodies caused their downfall.
“As climate shifts, maybe the production in the ocean could change,” Rao said. “And depending on what the ecosystem responded to, there could be less food availability” for marine life today just as those causing the demise of the megalodon sharks.
And that’s where the nitrogen fingerprint in the teeth comes in. The nitrogen isotope levels change in warm spells compared to ice ages so that Rao can track climate change in the distant past. Nitrogen isotopes from the Atlantic and Pacific Oceans mix during warm spells but ice ages lower sea levels, cutting off Atlantic from Pacific waters and and leaving a distinct isotope in each ocean. ,
Rao shared her research at the Comer Climate Conference this fall, an annual gathering of global climate scientists held virtually for the third year due to COVID-19. Comer conference veteran climate scientists, graduate students and post-docs investigate the effect of climate change from ancient life forms to theoretical models.
While Rao’s work examines a species belonging to an ancient era, another Comer scientist’s work takes estimations of the possibilities for the future.
Edmund Derby, a climate science Ph.D. student at Oxford University, utilizes simple models of Arctic sea ice from his past research in 2009 to examine the bifurcation or tipping point accompanying ice cover changes throughout the season.
Derby’s research presents climate from basic principles to its core behavior. In the scientific model, when atmospheric carbon dioxide exceeds a certain point, after all the Arctic ice melts, it is no longer possible to gain back the ice. His research presented at the conference investigates this tipping point under a model when the Arctic is covered in ice all year round.
“When you’ve reached this tipping point, you don’t get a reversible change once you’ve lost your ice cover,” Derby said.
The temperature of the Arctic is intrinsically connected with global warming across the rest of the world. In a phenomenon known as Arctic Amplification where the Arctic warms twice as fast as the rest of the world, which has warmed in excess of 1 degree Celsius (1.8 degrees F) with global warming due to emissions from human reliance on petroleum-based fuels.
The ice has the light reflective property that redirect the heat. But as it melts, the heat-absorbent ocean water takes its place, according to Derby.
With heat transport to lower latitudes, as the Arctic warms up, the transfer of heat to the Arctic would be expected to decrease.
However, in a changing climate, the transport of water vapor or clouds into the Arctic can counteract the cooling of the heat transport. The water vapor causes local temperature in the Arctic to rise.
In his research, Derby is adding more factors into the model to make it more realistic to the Arctic ice cover, and to investigate how the global rise of greenhouse gas will impact the ice melt at a local level.
Rao said, in her field of geoscience, the past informs the present and the future. Studying the ancient past of Earth’s environment builds a better understanding of the complex systems involved.
“Only when we can really understand or estimate the future better, then we can come up with better plans in terms of how we do climate adaptation and climate mitigation,” Rao said.
The numbers of climate change may seem small, but a small change now may mean a colossal shift into the future. <The changes are occurring now – we don’t want to suggest this is a problem for the next millennium.
Through Rao and Derby’s research of both the past and the future, concerns of climate change continue to loom in both the vanishing fabric of the Arctic and the demise of a species.
Photo at top: Arctic water and the atmosphere help scientists reconstruct the past climate record and inform models for the future. (Photo by Kai Boggild, distributed via imaggeo.egu.eu.)
By Brittany Edelmann and Carly Menker, Photos by Carly Menker, May 1, 2022 –
Janyiah, a ninth-grade student at Gary Comer College Prep, started “falling in love with science” three years ago in the South Side school’s proactive STEM curriculum. She enjoyed the mix of her two favorite subjects: math and reading. Janyiah, in the Comer middle school at the time, is now a freshman at Comer Prep in Jessica Stevens’ environmental science class. Janyiah said she and her classmates transmitted electricity to a light bulb, and “it was so cool.”
Skylan, also a ninth grader at Gary Comer College Prep, is finding her passion through Steven’s class as well. “I want to be a wildlife conservationist,” Skylen said. She said she noticed how Stevens is an environmental scientist and seeing what she does and how she goes out into the field really helped her decide what she wants to do.
At the age of 14, Sanaa was a Green Teen at the Gary Comer Youth Center when she was “working as a small little agricultural farmer,” and started learning about growing food and environmental science. Then she graduated and became a part of the Comer Crops Program. She loves seeing the growth, seeing food that she planted and seeing Maine in the summer to give more students the chance to experience this type of work and provide further inspiration and confidence to pursue a career in science.
Scientists come to speak with current students often. Stevens said students tell her how much they love talking to a “real scientist,” which shows them the researchers aren’t as “boring” as they originally thought.
Students in the middle and prep school and members of the youth center, all on the Comer Education Campus at 7200 S. Ingleside Ave., where the focus is on impacting their communities and beyond through hands-on, interactive learning related to science.
The underlying hope of founder Gary Comer had in regard to the program was about “how young people could learn here and then go out in the world and make a difference,” Marji Hess, previous urban agricultural director at GCCP, said at the 2021 annual Comer Climate Conference. The conference brings together top scientists from around the world to discuss their research that documents climate change and urgent solutions. Hess now leads a new Comer Family Foundation initiative empowering youth to address the climate crisis.
Students at the prep school (GCCP) have had opportunities to travel to Mongolia on field trips with scientists, experiential learning they took back into the classroom to inspire other students. Hess also said GCCP students have traveled with her to Yellowstone National Park for a week and “every single one of them said it changed their lives in a way that they never expected.”
Patricia Joyner was one of those students. She went to Yellowstone three years in a row and she’s now an undergraduate studying with Aaron Putnam, an assistant professor of Earth sciences with the University of Maine’s Climate Change Institute and a scientist affiliated with Comer climate research initiative. Another initiative they hope to implement is to take current GCCP students to Maine in the summer to give more students the chance to experience this type of work and provide further inspiration and confidence to pursue a career in science.
Stevens implements “culturally relevant and hands-on,” learning with the goal that her students “become scientifically literate adults and hopefully climate leaders.” Stevens is also working on piloting a student-centered climate change unit for the first time this year, which will include things like the topic of heat islands but specific to Chicago.
She received a grant to purchase handheld air quality sensors so her students can do a long-term investigation into air quality around the school. They hope to compare different areas around the school and how air quality affects human health. “Most of our students are in those zones and are in the communities that experienced the worst of environmental effects due to redlining,” so this experiment is especially impactful, Stevens said.
A day in the life of her classroom offers experiences her students say they cherish and enjoy.
(Note: For reasons of privacy and safety, students are identified by first name only.)
By Poonam Narotam, Dec. 15, 2021 –
When he’s not teaching earth science classes and analyzing data at the University of Maine, glacier whisperer Aaron Putnam is trekking into the high Himalayas or New Zealand’s Southern Alps to study where glaciers once stood.
The United Nations officials behind the recent global COP26 climate conference urged countries to eliminate carbon emissions by 45% below 2010 levels by 2030 to stabilize global warming driven by fossil fuel use. No definitive commitments were made toward that goal.
Researchers deepen our knowledge of climate systems and models in the hopes of awakening the urgent need for international solutions before global warming hits a tipping point. Putnam asks the big questions vital to modeling future climate patterns: What caused the last global ice age and how did it suddenly end?
“We need this information from the past to help calibrate our understanding of what’s coming in the future,” said Putnam, 40, an associate professor of earth science at the University of Maine.
Putnam is one of many paleoclimate scientists who studied under and worked with George Denton, distinguished professor at the University of Maine’s School of Earth and Climate Sciences and Climate Change Institute. Putnam and Denton spent the better part of a decade developing a new hypothesis published in March introducing how the westerly winds, the earth’s strongest wind system, contribute to climate shifts between glacial (when glaciers grow) and interglacial periods (when glaciers decline). Both scientists discussed their research at the Comer Climate Conference this fall, an annual gathering of international researchers held remotely this year due to the pandemic.
The findings prompted Putnam to look closely at the similarities between modern global warming and the end of the last ice age, the primary difference being that the pace of today’s climate change is escalating due to human-induced carbon emissions. Putnam, along with Denton and other paleoclimate scientists in their group, tested the hypothesis by mapping key glacier sites in both hemispheres. They found this dynamic system could have a dramatic impact on melting ice in the Southern Hemisphere and global sea level rise.
Putnam studies the land and patterns of rocks to identify where glaciers used to be. He draws detailed maps of the ridges and valleys, and collects rock samples. His research teams ship hundreds of pounds of rock to the Maine lab for testing to determine when the ice sheet melted and exposed the rock.
Using chemical analysis techniques, graduate students measure the amount of the isotope Beryllium-10 in the rock. The isotope forms in exposed rock when cosmic rays collide with quartz. Piecing together hundreds of precise calculations, Putnam’s team develops a chronology of how that glacier grew and shrank.
As the pandemic prevented travel to Southern Hemisphere glacier sites, Putnam led fieldwork in Wyoming in July to study the Laurentide Ice Sheet, the largest ice sheet of the last ice age. The ice sheet covered the upper half of North America during the ice age and its retreat gouged out the Great Lakes we know today, filling them with meltwater. Expanding glacier chronologies in both hemispheres furthers our understanding of global climate systems and the new patterns Putnam and Denton have been studying.
“We were looking at the surface [of a boulder] to see if it would be good to sample,” said Lauren Woods, a master’s student on the Wyoming trip. “He just kind of leans down to the rock and whispers, ‘Tell us your secrets.’”
Reaching remote field sites
Glacier research also requires finding the right combination of flights, boating routes, drives and treks into some of the world’s most remote places. Putnam said it took his team a week to traverse the Lunana Snowman trek on the border of Bhutan and Tibet, a snowy route amongst glaciers along the main spine of the Himalayas
Disconnected from mainstream communications and living among communities that don’t speak English, Putnam’s group relies heavily on local guides to coordinate directions, emergencies, and food.
Putnam’s Ph.D. student Peter Strand said they bought a sheep from a local herder in Mongolia to keep everyone fed.
“It’s not a good place in the world to be a vegetarian,” said Strand, who jumped at the opportunity to sign on as Putnam’s first Ph.D. student.
“He’s always encouraging everyone to think big,” Strand said. He said Putnam prompts them with the question: “What can this really tell us about how the whole earth system works?”
Without much cell phone coverage, Putnam said he feels more present and able to think in the “glacial graveyards,” areas of land marked by bodies of water and ridges of rock, called moraines, lining the landscape where glaciers once discarded them.
The ‘science’ gene
“When you’re young, you think you’re invincible,” said Putnam. Now the father of a 3-year-old, he’s aware of the dangers of exploring remote terrains. “You had to go over a number of very high passes to get to where you’re going,” he said of his many adventures. “It’s not like you just go back downhill.”
When there was Wi-Fi in the Himalayas, Whatsapp was his lifeline to his wife and baby. Nowadays, he looks forward to spending fewer than four months a year in the field in favor of his dad duties.
Putnam’s love of science runs in the family. His father, archaeologist David Putnam, took a college class with George Denton, who later became Putnam’s Ph.D. adviser. Putnam’s wife is a paleoceanographer and led research on a cruise off the Gulf of Maine in August.
“We’re trying to see if we can begin to plan our fieldwork in ways that we can do it together,” Putnam said. The climate science couple is considering Southern California for her research and New Zealand for his.
They haven’t been in the field together since Putnam’s wife visited him in New Zealand several years ago and he proposed on a peak of the Tasman Glacier.
“I was kind of a nervous wreck about the whole thing, like what if she says no?” Putnam said. She said yes, and they helicoptered back down to finish the day’s work.
Growing up in the Arctic Circle
When Putnam was in high school, his family spent a year in Utqiagvik (then called Barrow) in the northern tip of Alaska.
“We could see when the sea ice [or frozen ocean water] would come in and when it would leave,” Putnam said. The deep north first exposed him to how climate impacted people. The Inupiat people native to Alaska travel over sea ice to hunt and fish for food during the winter.
He celebrated his eighteenth birthday with his biology teacher in the Arctic Ocean on an icebreaker, a ship designed to cut through the ice sheets on the water. His mom snuck a birthday cake for him onto a helicopter during a supply run from the mainland.
“She had me thoroughly embarrassed,” Putnam said. “But that [trip] really clinched it for me; I knew somehow I wanted to get involved, I wanted to be a part of the climate science community.”
“There’s just some sort of intrinsic curiosity in trying to figure out how things work,” he said. “That’s what I find fun about it.”
Determined to continue developing glacier chronologies to advance climate research, Putnam is laying plans for next year’s field seasons – hopefully to Patagonia. His and others’ glacier chronologies demonstrate the complexity of dynamic global climate cycles documented across much of the past 1 million years. And yet, scientists agree that human-driven ice melt and climate change is eclipsing the speed at which climates changed in the past.
Photo at top: Glacier geologist and paleoclimate scientist Aaron Putnam, 40, snaps a photo of a boulder in Soda Lake, Wyoming, in July 2021. The Laurentide Ice Sheet covered the northern regions of the continent, including Wyoming, during the last ice age. The retreat of the ice sheet gouged out the Great Lakes we know today and filled them with meltwater. (Lauren Woods/UNIVERITY OF MAINE)
Poonam Narotam is a health, science, and environment reporter at Medill. You can follow her on Twitter at @namsorama.
Even summer days are cold in the Allan Hills Blue Ice Area, a meteorite-strewn expanse of glacier flanked by mountains at the eastern edge of the Antarctic ice sheet near the McMurdo Station research center.
Jeff Severinghaus, a paleoclimatologist at the Scripps Institute of Oceanography, and his colleagues at Princeton University discovered here in 2017 a 2.7-million-year-old chunk of glacial ice containing bubbles of trapped air from Earth’s ancient atmosphere.
That ice turned out to be contaminated by modern air, destroying its link to climate conditions millions of years ago. But the discovery reinvigorated the quest in the ice core science field to find the world’s oldest ice. Right now, the continuous record from a single ice core goes back only about 800,000 years.
In coming years, the world will be a much warmer place – average temperatures will increase by 2 to 3 degrees Celsius (3.6 to 5.4 degrees Fahrenheit), and arctic temperatures will rise by twice that rate. Over the next 10 years, paleoclimatologists hope to extend the ice core record back to 3 million years ago, when they know from climate clues in deep sea sediment cores that the Earth was last that warm. As the planet heats up today, many questions remain. How bad will hurricanes get? How frequent will forest fires become? How high will seas rise?
“The only practical way to know the answers to these questions is to get ice cores that are 3 million years old,” Severinghaus said. “It’s the only way to look into our future and see what we’re in for.”
Severinghaus has spent the last 25 years in Antarctica and in his lab in California studying the composition of gases in polar ice. Ice cores, he said, are key to understanding how Earth’s climate changes with varying levels of atmospheric carbon dioxide.
“There’s no other way to get a sample of the ancient atmosphere, other than the air bubbles in ice cores,” Severinghaus said. “From the ice cores, we learned that carbon dioxide concentrations have never been as high as they are today.”
The natural atmospheric carbon dioxide concentration over the last million or so years was 280 parts per million during warm spells and 180 parts per million during the cold snaps of ice ages. Today, CO2 levels hover at an unprecedented 420 parts per million due to human-generated fossil fuel emissions.
A new collaborative global effort is hot on the trail of the ancient ice, Severinghaus reported at the annual fall Comer Climate Conference, held virtually this year on Oct. 4-5.
Ed Brook, a paleoclimatologist at Oregon State University, received the good news in Februrary – the National Science Foundation selected his proposal for an ice-core-focused Science and Technology Center he calls COLDEX, the Center for Oldest Ice Exploration.
Over the prior two years, Brook brought together 30 of the nation’s leading paleoclimatologists representing 13 universities to jointly apply for the grant, which includes $25 million in funding over five years with a likely extension to 10 years and $50 million in total. Brook said the center represents the ice core field finally uniting a “critical mass” of researchers to justify such a massive investment in paleoclimate research.
“It was so rewarding, because the right collaborators really stepped up and were interested in making this happen,” Brook said. “But it’s not for the faint of heart to try to organize this many people.”
As the Earth continues to warm, the race to find Antarctica’s oldest ice and understand historic climate change is accelerating – across the continent, the EU, Japan, Australia and Russia also are beginning multimillion-dollar drilling operations, and China’s effort has been underway, with slow progress, since 2012.
With its unprecedented level of funding, COLDEX’s explicit goal is to drill a single continuous deep ice core 1.5 million years old that is likely to be between 1.5 and 2 miles long and then extend the record back further to 3 million years through a composite of discontinuous “snippets” of ice from across the continent. Even though the Antarctic sheet is 2 miles thick in some places, it flows, melts and fractures over time, so researchers think 1.5 million years is the limit for a single core in one location. The oldest ice tends to exist in chunks at the windswept rocky edges of the sheet, like at the Allan Hills site.
“When you get back to 3 million years, there’s no ice that’s still intact stratigraphically – it’s all chopped up and mixed out of order, like a deck of cards that’s been shuffled,” said Severinghaus, who’s a co-principal investigator on COLDEX.
“These patches are out there,” Brook said. “But we don’t know exactly where they are or how many of them there are.”
Severinghaus compares reconstructing the ice core record to an archaeologist reassembling pieces of broken pottery to build a whole. Thanks to advances in geochemistry – paleoclimatologists can now study ancient atmospheric changes using argon, nitrogen, krypton and xenon isotopes in addition to the less accurate oxygen isotopes used in the 1970s – and the fact that atmospheric gas composition is the same throughout the world at any given point in time, COLDEX researchers can put together hundreds of puzzle pieces of ice from across Antarctica in the correct historical order.
“We’re pretty confident we can construct a continuous composite record of the ancient atmosphere,” Severinghaus said. “It’s just going to be a bit of detective work.”
Drilling the 1.5-million-year-old deep ice core might prove just as challenging. Drilling ice cores is a slow, expensive process that requires heavy equipment. Researchers must travel inland, far from McMurdo Station, and establish a base camp where they’ll live and work for the season, which lasts the austral summer – October to February – when the sun never sets. During the winter, temperatures sink to -50 degrees Celsius (-58 degrees Fahrenheit), and the continent plunges into continuous darkness.
“It’s like being at sea,” Brook said. “There’s nothing to see except for snow. And it’s cold. The work is hard.”
Drilling rigs cut through the ice sheet a few meters at a time, and researchers hoist out heavy sections of core as the drill descends. It’s a slow, repetitive process. A 3,000-meter core (more than 1.8 miles) could take up to three seasons – three years – to complete.
The challenge, then, is to find an inland site with deep and old enough ice to justify setting up the COLDEX drilling camp. But much of the deep interior of the Antarctic ice sheet where that old ice likely is has never been mapped – scientists don’t know how deep the ice is.
“It’s just a blank spot on the map,” Severinghaus said. “So, we’re doing basic exploration at this point.”
The first five years
The COLDEX initiative kicked off in earnest in September. Brook is currently hiring researchers, coordinating with NSF logistics contractors to organize trips to Antarctica and building websites and lab spaces. Initial fieldwork – including testing a new fast thermal melt probe called Ice Diver in Greenland – is set to begin in 2022.
While some scientists – including Severinghaus and the Princeton team – continue searching for chunks of old ice at the ice sheet’s fringes and drill rapid 100-meter shallow cores there using Severinghaus’ Rapid Access Ice Drill, others will begin reconnaissance work to find the best site for the 1.5-million-year-old core.
“We’re going to be doing airborne radar echo sounding with new technology in a broad region from the South Pole towards Dome A,” an ice coring site, Brook said. “We’re looking to gather data that would help us put teams on the ground to do detailed radar in specific locations.”
Antarctic “domes” are the highest points on the ice sheet – locations where steady snowfall piled up over thousands of years to create particularly thick ice ideal for drilling old cores. A European team extracted the 800,000-year-old record core in 2013 at Dome C. Japan plans to drill for a 1.5-million-year-old core at Dome Fuji, Russia at Dome B, and Europe and Australia at Dome C.
Recent advances in aerial ground-penetrating radar make it possible for scientists to detect the thickness of the ice sheet as well as layers of dust impurities that indicate colder versus warmer periods – and thus the relative age of the ice. Ground teams will then follow up at two candidate sites with the Ice Diver reconnaissance drill, which can date ice quickly using a laser that detects dust variations, to narrow the choice down to one site.
“We want to know before we get into the $50 million logistics of drilling a deep ice core that the target ice is really there,” Severinghaus said.
The second five-year period will be dedicated to drilling and extracting that 1.5-million-year-old deep ice core and sharing it with the entire field for data analysis.
That core will also help scientists answer the mystery of the Mid-Pleistocene Transition. Around 1.2 million years ago, the length of the transition between cold and warm climate periods abruptly shifted from 41,000 to 100,000 years. Scientists think changes in atmospheric carbon dioxide were to blame, but an older core would provide proof.
“Earth science has a diversity problem.” Brook said. “Some other fields have made progress, but that’s just not true in the earth sciences. And polar science is near the worst end of that spectrum, at least anecdotally. The exploration of Antarctica and Greenland has been perceived as a white male thing for quite a while.”
That’s where the second half of COLDEX comes in – diversifying the ice core field by establishing partnerships with a variety of minority-serving organizations to combat stereotypes and form new pipelines into the field and directly into COLDEX research work over the next 10 years.
“So, it’s only half about finding the oldest ice on the planet.” Severinghaus said. “The other half is doing public facing diversity, equity, inclusion and outreach.”
For example, in the past 40 years, only 20 Native American women earned geosciences doctorates. Sarah Aarons, a paleoclimatologist and Alaska Native at Scripps, will lead a partnership with the Alaska Native Science and Engineering Program to recruit Alaska Native students into the geosciences and, through the NSF’s Research Experiences for Undergraduates program, involve them directly in COLDEX.
“We know the climate is changing twice as fast in the Arctic, and so having Alaska Native people who are experts in climate and the environment in positions in academia or government who know what’s happening in the region they’re from is really, really important,” Aarons said.
Stereotype inoculation theory states that people tend to choose to mentor other people who come from a similar racial or ethnic background or share lived experiences. With the polar sciences dominated by white male researchers, that’s a problem for recruiting new students.
“So, we also plan to do work within our own community to try to understand what kinds of biases we may have and how to overcome those and make our community more welcoming,” Brook said.
“The exciting thing about COLDEX is it’s bringing together a group of people from a really wide variety of research backgrounds into the same room who are all committed to the same goal – finding the oldest continuous ice core record – and combining our expertise to tackle that question,” Aarons said.
In November, world leaders gathered in Glasgow for the UN’s COP26 climate change conference. They were shown a vial of air from 1765, the beginning of the industrial revolution, extracted from Antarctic ice and a section of an ice core, ancient air bubbles slowly, audibly popping as it melted away in front of them. It was a powerful and urgent illustration of both polar ice’s fragility and its ability to describe our ancient atmosphere – where we’ve been and where we’re headed. Through COLDEX, our nation’s paleoclimatologists hope to provide the clearest picture yet.
Photo at top: Jeff Severinghaus (L) and fellow COLDEX participant John Goodge hold an ice and rock core recovered during a test of rapid drilling equipment designed for ancient ice reconnaissance. (Courtesy of Jeff Severinghaus)
Christian Elliott is a science and environmental reporter at Medill. You can follow him on Twitter at @csbelliott.
By Christian Elliott and Brittany Edelmann, Dec. 8, 2021 –
Nearly 20 years ago, then Ph.D. student Gina Moseley walked into a bar in Bristol to meet fellow members of the University of Bristol Spelæological Society caving club. An older caver talked with her over drinks about some small caves in northeastern Greenland he’d always dreamed of organizing an expedition to explore. But, “logistically, it’s a nightmare to get out there,” said Moseley, now a professor in the Institute of Geology at the University of Innsbruck in Austria. The caver gave her all the papers he’d collected on the caves, and for years she kept them filed away.
Much later, a 1960 article by U.S. military geologists among the papers caught her eye. In their search for prime airfield locations, the geologists discovered caves with interesting geological features — crystalline calcite, stalagmites and flowstone deposits. To Moseley, that was proof Greenland’s caves contained something critical to scientists’ understanding of Earth’s ancient climate.
Moseley took her first steps into caving years earlier with her mom on a holiday trip when she was 12. She loved it. As she started grad school in Bristol, she discovered she could bring together her fascination with caves and her interest in studying paleoclimate to understand how future climate change — pushed by fossil fuel emissions of human activities — will affect the Earth.
Caves are normally “not altered or impacted by other processes” and “they’re so well-preserved over thousands of years,” Moseley said. That makes them a great location for climate research and creating records that can function as important analogs for future climate change.
The 2021 Comer Climate Conference on Oct. 4 – 5 brought together scientists from around the world, including Moseley and fellow paleoclimate researcher Kathleen Wendt.
“Devils Hole was where it all began. That was the start of cave paleoclimate research,” Moseley said. Paleoclimate scientists first rappelled down into the deep, narrow cave in the Amargosa Desert in southwest Nevada in the late 1980s.
Using cores of the thick calcite crusts on the cave walls, which accumulated steadily over time, researchers reconstructed 500,000 years of climate history here with Uranium-thorium dating. Uranium-thorium dating provides insight into when a rock was formed– giving a date to the origin of the rock.
Devil’s Hole was also where Moseley and Wendt, who has her Ph.D. from the University of Innsbruck in Austria, got their start in cave paleoclimate science. In 2017, they returned to Devils Hole to extend the climate record further and validate the older results.
In their research Moseley and Wendt focused on oxygen isotopes, which provide temperature information about historic temperatures. During ice ages, a heavier isotope of oxygen forms at higher levels than during warm spells.
Wendt is getting ready to submit a new paper on the oxygen isotope record from Devils Hole. By showing the fluctuation in types of isotopes, heavier versus lighter forms of oxygen, this will give “clues into changes in temperature and a little bit about the source of precipitation over time,” Wendt said.
They found the water table dropped below modern levels during the last interglacial, 120,000 years ago, when Earth’s orbit brought the planet closer to the sun. That time period is an analog for southern Nevada’s hotter and drier future that will be accelerated beyond natural planetary fluctuations with human-forced extremes of climate change.
“Studying the paleoclimate tells us what nature is capable of,” Wendt said.
The Greenland caves
Paleoclimatologists who focus on caves often study speleothems — mineral deposits formed by dripping water. Protected within caves from the elements, these dripstones (stalagmites and stalactites) and flowstones grow as layers of calcium carbonate carried by rainwater add up over hundreds of thousands of years.
One of the flowstones Moseley found in the caves was specifically mentioned in the 1960 paper that inspired the expedition.
In Greenland, now a rainless polar desert, speleothems formed during a time when the island’s climate was warmer and wetter. By collecting and sampling speleothems, Moseley can reconstruct that ancient climate period as an analog for the future, when Greenland will once again be warmer and wetter.
Over millions of years due to orbital changes, Earth’s climate alternates between warm and cold periods — interglacials and ice ages called glacials. Paleoclimatologists rely on air bubbles in cores taken from ice sheets in Greenland and the Antarctic to study the composition of the ancient climate’s atmosphere, but there’s a problem — during warm periods, the ice sheet melts. That’s where the caves come in.
“So the caves offer the polar opposite of what the ice cores do because the ice cores tend to be cold-based climate records and the caves can give us warm-based climate records. So, we get to the two different parts together,” Moseley said.
That’s a common theme in paleoclimatology — no one climate proxy shows the big picture. To fully understand Earth’s ancient climate, scientists must piece together hundreds of pieces from data from sources across the world.
“If you have one cave in one location, that’s kind of interesting. But if you can relate that to other caves in other locations, ice cores in other locations, deep sea sediments in other locations and get the whole picture, that’s where it really gets interesting. That’s where we can answer the big questions and tackle the big issues,” Moseley said.
As the Arctic continues to warm at twice the rate of the rest of the world, understanding what warm and wet historic climate periods were like can help scientists know what to expert in the imminent future.
This leads to Moseley’s next adventure in 2023, where she will explore completely untouched caves in Northern Greenland. This was only made possible with an award from Rolex — which provides funding for such an endeavor.
Christian Elliott and Brittany Edelmann are science and environmental reporters at Medill. You can follow them on Twitter at @csbelliott. and @brittedelmann.
Climate change is pushing precipitation to both extremes. The elevated annual mean temperature in the United States is accompanied by higher levels of rain and snow in the eastern, southeastern and midwestern regions of the country and decreases in precipitation in the western and southwestern areas, according to the National Oceanic and Atmospheric Administration (NOAA).
“The basic result is that we (will) see more floods and more droughts,” said Richard Alley, a climate scientist and professor of geosciences at Pennsylvania State University, during the annual 2021 Comer Climate Conference, held virtually this year. “You get more intense events in a warmer world.”
Climate change has heightened the need to predict and prepare for extreme precipitation events, but it has also impaired the ability to do so. According to NOAA, the United States’ average seasonal precipitation skill — the accuracy in forecasting the amount of precipitation over an upcoming season in a specific region — has declined in recent years.
Precipitation skill varies for different areas, in part because naturally occurring cycles in ocean temperature have a well-documented effect on precipitation trends. El Niño, a climate phenomenon resulting from a warming of the central and eastern Pacific Ocean that occurs every three to seven years on average, has a consistent impact on rainfall in the places along its path each time it strikes.
Seasonal precipitation skill is “actually pretty good in places that are affected by El Niño because we can predict El Niño, and El Niño statistically affects weather patterns,” said David Battisti, a professor of atmospheric sciences at the University of Washington.
Elsewhere, however, technology has struggled to keep up with new variables as the climate evolves. The impact of climate change on precipitation — and precipitation skill — can be largely traced to the ocean, which stores approximately 93% of excess heat driven by emissions from fossil fuel use, according to the Intergovernmental Panel on Climate Change.
“If you heat the planet, you get more evaporation from the ocean, just like if you heat a pan on your stove, you start to get steam coming off of it,” Battisti said. The additional water vapor in the air means when conditions are right for rain, it rains harder.
As the relationship between rising ocean temperatures and precipitation became clear, the U.S. National Weather Service realized it needed to incorporate ocean processes into its forecasts, said Joellen Russell, a climate scientist and oceanographer at the University of Arizona, at the Comer Climate Conference. However, rather than developing a new climate model that integrated ocean from the start, the ocean element was tacked onto the existing atmosphere component.
“They coupled it, but it wasn’t really designed to be coupled,” Russell said, resulting in a weather simulation that cannot account for the full network of interactions between ocean and atmosphere. It more closely resembles a layer of red painted over a layer of blue than a pointillist blending of red and blue dots that appears purple.
The accuracy of U.S. precipitation prediction tools is also limited by the lack of information on ocean conditions due to shortcomings in operational oceanography, Russell said. For example, orbital satellites often sample from confined and redundant areas, collecting spotty real-time data to feed into the model.
While some scientists focus on how to gather and use current data to further improve seasonal precipitation skill, other researchers are looking to the past to predict the long-term impacts of climate change on precipitation in specific regions. Dylan Parmenter, a Ph.D. student in the Department of Earth and Environmental Sciences at the University of Minnesota, presented his work studying the chemical composition of stalagmites to reconstruct rainfall patterns in the Amazon at the Comer Climate Conference.
Stalagmites form when water vapor carried from the ocean combines with the soil at a cave site and drips onto the floor of the cave. In this way, “stalagmites are kind of like fossilized precipitation,” Parmenter said. The oxygen atoms in the water vapor exist as two versions — one heavier and one lighter. If it rains as the water vapor cloud travels, the heavier oxygen atoms fall to the ground with the rain before reaching the cave. By measuring the ratio of the two types of oxygen in a sample of stalagmite, Parmenter can estimate the precipitation conditions when the stalagmite was created. To determine the age of the sample, he measures to what extent uranium atoms in the stalagmite have decayed, expelling some of their subatomic particles.
These ancient rainfall records can help scientists understand the effect of past climate patterns on precipitation, providing a useful reference point when predicting the impact of modern climate change.
“If we want to know how precipitation in a certain region is going to change from climate change, there’s nothing to compare that to,” Parmenter said. “Our work is going back and saying: With these natural climate change processes in the past, how did it react?”
While Russell acknowledges there is no time in history perfectly representative of the current climate conditions, the fundamental insight gained from research like Parmenter’s will be critical in informing responses to climate change.
“We are in the undiscovered country of the future, as Shakespeare put it. So, no, it’s not going to be exactly the same as any previous (time),” she said. “But being able to look at how these mechanisms have worked in the past can help us accelerate the learning that is going to be required to do the preventing, the mitigating and the adapting.”
Featured photo at top: A satellite image captures Hurricane Laura’s landfall. (Image source: NOAA)
Sarah Anderson is a health, environment and science reporter at Medill and a Ph.D. chemist. Follow her on Twitter @seanderson63.
“Tropical glacier” — the term sounds like an oxymoron and, due to climate change, it might become one.
These bodies of ice nestle in the mountain ranges of tropical regions, providing a major source of freshwater and tourism revenue. But studies predict most tropical glaciers will disappear within the next 10 years taking critical water resources with them.
“It’s hugely important to understand the rate at which these glaciers are melting,” said Alice Doughty, a lecturer of Earth and climate sciences at the University of Maine.
Doughty and Meredith Kelly, a professor of Earth sciences at Dartmouth College, are developing a model to investigate tropical glacier melt in places such as the Rwenzori Mountains in Uganda and the Sierra Nevada del Cocuy in Colombia. They presented their findings at the virtual 2021 Comer Climate Conference, an annual event usually held in southwestern Wisconsin.
Glaciers sand down the rock beneath them as they melt, acting “sort of like bulldozers,” Kelly said. The debris piles up, depositing a series of ridge-like features called moraines at the glacier’s retreating boundaries. Kelly examines satellite images of a glacier site to identify moraines the glacier left behind, then analyzes samples of rock to determine when the moraines were created. By measuring a type of beryllium atom that accumulates in the rock as it is exposed to Earth’s atmosphere, Kelly can approximate how long ago the rock was freed from the ice’s hold to form the moraine. Collectively, this information allows her to generate a map of the size and shape of the glacier at a specific time in the past.
Doughty then works to develop a computer model to simulate how climate variables interact to produce the glacier. She tries to “grow the glacier,” adjusting temperature, precipitation and other inputs until the glacier output matches Kelly’s map.
Data from any nearby weather stations provide a useful starting point; observing whether current climate conditions yield the modern glacier helps her evaluate the model. When the simulation is optimized, Kelly and Doughty will be able to use it to predict the effect of climate change on glacial melt.
“Once we calibrate the model, we can just as easily make things warmer,” Doughty said. “And so we can have estimates like in the Rwenzori, one degree of warming and those glaciers are gone.”
Other scientists are interested in developing similar models for the melting of sea ice, “a really big part of the climate system,” said Ed Brook, a professor of Earth, ocean and atmospheric sciences at Oregon State University.
Sea ice helps insulate the ocean from heat and gases in the atmosphere and contributes to sea level rise when it melts, but it doesn’t leave behind the same physical record as glaciers. While seasonal sea ice melting can be tracked using IP25, an organic molecule produced by algae that grow along the receding ice edge, the presence of permanent sea ice in the past has remained elusive.
“We don’t have a very good method for reconstructing how much sea ice there was at any particular time,” Brook said.
Frank Pavia, a postdoctoral researcher in geological and planetary sciences at the California Institute of Technology, presented his research at the Comer Climate Conference, exploring a new way to monitor this more stable sea ice cover. His method relies on interplanetary dust particles, the solar system’s version of dust that rains down on Earth from outer space.
Interplanetary dust particles deposit a light type of helium atom onto the sea floor. If the surface of the ocean is blocked by ice, however, the particles (and the helium) can’t enter the water. Pavia is examining whether the amount of helium in the ocean floor can be used as a measure of sea ice cover. To account for any differences in helium levels due to changes in how fast atoms settle to the sea floor, he also measures a special thorium atom that is produced inside the ocean and sinks to the bottom at a constant rate, regardless of ice cover.
To test his method, Pavia acquired samples of the floor of the Arctic Ocean from the Last Glacial Maximum, one period of well-characterized sea ice cover in the Arctic. The age of the samples had been previously determined by measuring a radioactive form of carbon in the shells of tiny marine organisms that indicates when they were alive.
When sea ice cover was thick, Pavia detected high amounts of thorium but low levels of helium, demonstrating that while atoms were efficiently burying in the sea floor, helium couldn’t access the ocean due to the sea ice. When there was no sea ice cover, he measured similar signals for both thorium and helium, revealing that the helium atoms were successfully deposited into the ice-free ocean. Pavia is also interested in seeing if the period of melting in between gives a surge in helium, corresponding to an influx of interplanetary dust particles that accumulated on top of the ice over time.
While accurate measurements will require that the dust particles are evenly distributed in the ocean floor rather than concentrated in specific pockets, the approach “has a lot of promise,” Brook said. The prospect of detecting nonseasonal sea ice melting — an event that leaves very few fingerprints — via a helium spike could be a major advantage of the method, he said.
“It’s potentially very important, because if the pulse of particles was the signature of melting a bunch of permanent ice, then you would have a sign of that process, which would be very hard to see other ways,” Brook said.
After further validation, Pavia plans to use his method to reconstruct poorly understood sea ice patterns during past periods of warming in the Arctic. Like Kelly, he aims to provide a map that other researchers can use to test and refine models that simulate sea ice melting as climate change progresses.
“The hope is to help improve the projections of sea ice coverage into the future in the Arctic,” Pavia said.
Featured photo at top: Meredith Kelly and Alice Doughty study the pace of melting of tropical glaciers like this one in Uganda’s Rwenzori Mountains. (Image courtesy of Alice Doughty)
Sarah Anderson is a health, environment and science reporter at Medill and a Ph.D. chemist. Follow her on Twitter @seanderson63.
COVID-19 swept the world, with little regard for anyone who stood in its path. Within weeks, the virus killed thousands, isolated people in their homes and sent economies plummeting.
Not only did COVID-19 overwhelm the United States health care system during the first surge, but our political leaders failed to mobilize alongside health experts to combat the virus together.
Consequently, the pandemic rages on. Today, almost nine months after the first reported coronavirus case in the U.S., more than 220,000 people have died.
“We are the richest country in the world. We have all this knowledge and capability, but it didn’t matter because we did not have trust,” said Joellen Russell, a professor of biogeochemical dynamics at the University of Arizona.
Without serious reform, environmental scientists at the 2020 Comer Climate Conference fear we are risking the same mistakes again with the far greater global threat of climate change.
Climate change impacts have accelerated in recent years, triggering more frequent and severe hurricanes, wildfires and heat waves. Conference attendees shared the concern that the heightened mistrust between scientists and many political leaders adds yet another barrier to effective legislative action and renders our communities increasingly vulnerable to the rapidly changing environment.
“Climate change is the pandemic without a vaccine,” said Raymond Pierrehumbert, a professor of physics at the University of Oxford. While biological innovation, including an expected vaccine, will bring COVID-19 under control, scientific knowledge alone cannot slow climate change. We have to act together and we have to act now, he added.
Failure to take collective action quickly may have been the biggest U.S. mistake in limiting the spread of the pandemic. The Trump Administration did not consider the virus as a serious threat until two months after the first COVID-19 case was reported. President Donald Trump left individual states to create their own stay-at-home protocols, which was why some reopened too early. He continues to undermine the recommended health guidelines of wearing face masks and social distancing. As a result, COVID-19 cases continue to surge at over 300,000 new infections on Dec. 17, with deaths hovering above 3,200 that day.
But this surge was not the case everywhere. For example, New Zealand championed rigorous prevention during the first outbreak and effectively curbed the spread of the virus.
“Science won,” said Russell, describing how New Zealand beat COVID-19. “People worked together. It requires a combination of willingness, leadership and science.”
Russell and other conference scientists urged that this balance be emulated around the world, starting with the U.S., to stem climate change. They presented their latest findings on melting glaciers linked to sea level rise and shifting wind and rain patterns, which can mean severe drought and crop failures. Delaying action can be disastrous, as seen with the pandemic, and the consequences of climate change are predicted to be even worse.
With global warming tied to fossil fuel emissions, conference scientists pointed to melting snow caps in the Himalayas depleting freshwater resources that over 1.9 billion people across Asia rely on. The warming climate is creating more dangerous outdoor working conditions in heat millions of workers can’t afford to avoid. Humans meddling with the ecosystem also drives the spread of pathogens and creates new vectors for the transmission of viruses from animals to people, such as COVID-19. A recent report from the United Nations Environment Programme and International Livestock Research Institute suggests that continued disruption of wildlife and the environment will make large disease outbreaks like COVID-19 more common. Closer to home, California and large swatches of the country are facing drought while the Midwest floods due to extreme rainfall.
As the world manages its reaction to this global crisis and prepares for the larger one at hand, scientists at the Comer Climate Conference identified two important lessons to be learned from the COVID-19 pandemic to help mitigate the imminent effects of climate change.
First, they called for added urgency to recognize the impact of carbon emissions and offer real-time updates to hold countries accountable for their energy policies that release greenhouse gases. Russell said without this transparency to encourage reform, climate change seems like a “big, endless problem instead of an immediate fight for our grandchildren’s future.”
Second, identify practical solutions. Many people oppose environmental reform out of fear that the economy will collapse even further, heightening the pressures of the pandemic. But veteran geoscientist Richard Alley argues that the shift to clean energy can actually stimulate the economy when viewed as an opportunity for political and technological innovation. Alley, a professor at Pennsylvania State University, was one of the founding mentors of the Comer Family Foundation’s support for climate research and fellowships. He sees energy innovation as a win-win for economic growth, human health, national security and the environment.
“We need to make energy something that is flexible and interactive so that people can use it in the way that is best for them,” Alley said. He suggested turning the electric grid into something like the internet, a platform on which people can buy, sell, and trade shares of resources. This way more people could access the financial and environmental benefits of clean energy without having to worry about investing in the individual resources for their properties.
Alley proposed a hypothetical example of a dairy farmer, struggling to stay afloat due to high costs of operation. Rather than paying for and installing a few solar panels for his roof, the farmer instead could invest in community solar, a power plant whose electricity is shared by multiple properties. The community grid sells solar electric power to homeowners who now no longer need to invest in their own solar panels. It’s cost-effective, and gives the farmer a greater chance at survival because now he has two crops—milk and energy—instead of just one.
In other words, instead of funding policies and lobbies to decide who gets to control our resources, we should be financing ways to make more efficient use of our resources, Alley said.
Solutions like this require a multidisciplinary team of scientists, engineers and economists. At the core of these efforts, however, lies the country’s leadership. Now, more than ever before, we need an administration who will provide a science-backed, coordinated response to climate change while prioritizing the well-being of its citizens.
In an old democracy like that of the United States, we have a mechanism to rectify the perceived lack of responsibility taken by elected officials, reminded Russell. Votes do matter.
Now is the time to trust our institutions and build a society that is committed to our future environment, health and quality of life—that’s the message Russel, Alley and many others conveyed.
Now is the time for individual action to promote collective reform. And it can start as early as November 3.
Shivani Majmudar is a health, environment and science reporter at Medill. You can follow her on Twitter at @spmajmudarr.