By Molly Glick
April 9,2018 –

Jim Gonksa left his home in Chicago’s Back of the Yards over 45 years ago when his father’s meatpacking job relocated to Bradley, Illinois, where land and rents were more affordable. Today, the majority of the neighborhood’s once-thriving meat processing plants have disappeared. The former Peer Foods factory site on 46th street lives on, absent of hanging carcasses and sausage linkers. The building is currently occupied by a kombucha startup, a beehive workshop, a bakery, brewery and a specialty ice distributor, among other niche businesses.

Today Gonska serves as director of community services for the Back of the Yards Neighborhood Council. He said he has noticed transformations in the neighborhood since his homecoming, particularly an increase in diversity and a drop in income due to the shuttered industrial giants. But the Back of the Yards could assume yet another identity in the coming decades as a different kind of business invests in the district. This time around, sustainable circular economies may replace assembly lines.

Peer Foods smokehouses have been converted into restrooms and breastfeeding stations. (Credit: Colin Boyle)

This is the vision of the non-profit Plant Chicago, founded in 2011 by Bubbly Dynamics, LLC. Plant Chicago facilitates the cooperative operations for 25 small businesses renting in the 93,500-square-foot facility known as The Plant. Plant Chicago has ambitious plans – it wants to change how we run businesses.

“Today we operate in a linear economy where resources are extracted, a product is manufactured and consumed by us…and then it goes to a landfill,” said Stef Funk, education associate at Plant Chicago. “Instead of wasting something, we’re redefining what waste itself means” among businesses at The Plant.  

The building’s tenants work to convert each other’s excess materials into valuable resources. Chickens roost in dried grounds from Turkish coffee-maker Four Letter Word, Funk said. The same grounds are incorporated into “bio-bricks,” along with a mix of sawdust and spent grain from Whiner Beer Company. Once the research is perfected, bio-bricks sourced from the Pleasant House Bakery could eliminate the need for firewood.

Plants thrive in the aquaponics system. (Credit: Colin Boyle)

Downstairs, an urban garden is illuminated by fuschia LED lights. Funk points to fish in a tank at the garden’s periphery. Here an aquaponics system pipes nutrient-rich water that is absorbed and filtered by plants and returned to the fish tanks. On their visits, local students gaze wide-eyed as they learn about how bacteria breaks down ammonia in the fish waste and provides plants with nutrients.

“It’s difficult for children to imagine things they can’t see, or even wrap their heads around the idea that there’s bacteria in here,” Funk said.

Plant Chicago offers free tours to Back of the Yards residents. Funk said that they are “the first people to know” about jobs at the non-profit and its interior businesses. Nearby high schoolers find work there, too.  

Plant Chicago also hosts farmers markets for residents, something Gonska said he doesn’t often encounter in the area. Gonska acknowledged how new businesses usher in much-needed resources. Still, there are concerns surrounding gentrification.

“We look at it as a positive,” Gonska said. “Any company that comes into the neighborhood, it’s positive for employment and the services that they offer the city.”

Now, Gonska sees less of the bakeries and butcher shops in Back of the Yards of his childhood. The last remnant of his father’s career here is the still-bubbling Bubbly Creek of the Chicago River, where decaying animal carcasses tossed there ages ago in a pre-EPA world continue to decay.


Photo at top: Stef Funk of the not-for-profit Plant Chicago displays a vintage blueprint of the sprawling Union Stockyards. The stockyards employed 40,000 people at its height in the Back of the Yards neighborhood where The Plant refurbished a meat processing facility, now home to Plant Chicago and 25 green businesses. (Colin Boyle/Medill)



By Adam Cohen, Jan. 30, 2018 –

It’s as if there’s a new apocalyptic blockbuster in theaters, and Joerg Schaefer has a front-row seat.

Some of the world’s foremost climate scientists shared their latest field research reports at the annual Comer Climate Conference this past fall in southwestern Wisconsin. None was as jarring as Schaefer’s talk on his work in Greenland and the Himalayas. His data indicating the vastly increased potential for sea level rise and severe water shortages are harrowing.

The renowned Columbia University professor gave two presentations, each on a paper that he published late in 2016. The first described a groundbreaking mission to drill through 2 miles of ice in the center of Greenland. The cosmic ray burn that Schaefer and his team found on the bedrock beneath the glacier indicates that, contrary to conventional wisdom, Greenland was completely ice-free during certain interglacial periods over the past 2.6 million years. The isotopes that were present in the sample – traces of beryllium-10, aluminium-26, and chlorine-36, among others – deliver the telltale clues that appear when cosmic radiation bombards rock uncovered by ice.

Schaefer’s mood was heavy as we sat down to speak in the library of the Comer Family Foundation estate after he had presented his findings. Outside the window to his right, a concrete landing strip gave way to the rolling hills of the Midwest’s Driftless Area. On a shelf to his left sat a leather-bound copy of Darwin’s Origin of Species. But Schaefer seemed weighed down by the subject matter of the day, unable to appreciate the treasures around him. “What I showed you today is another piece of bad news,” he said.

The expedition’s results may mean that Greenland is much more susceptible to climate change than we had thought. As we continue to warm our planet, the Arctic island could deglaciate in a matter of decades. And if it does, it will mean almost 25 feet of sea level rise.

Joerg Schaefer at the Comer Climate Conference last fall. (Adam Cohen/MEDILL)

The second talk Schaefer gave was based on a foray not into the Arctic, but into the archives of the American intelligence community. In a paper he co-authored and published in September 2016, Schaefer compared modern NASA imaging with recently declassified spy satellite data dating back to the early 1970s in order to build a series of digital elevation maps that quantify glacial retreat in the Himalayas.

The study is unprecedented in scope, as it traces the movement of roughly 18,000 individual glaciers over three decades, from 1974 to 2006, and thus isn’t skewed by regional variation for factors such as elevation and precipitation. Additionally, the Cold War-era, school bus-sized satellites, launched into orbit by the U.S. National Reconnaissance Office to keep tabs on the Soviet army, provide a clear picture of objects as small as 2-feet wide. That’s a resolution higher than current Google Earth imagery.

Unlike the Greenland results, the significance of the Himalayan satellite data is unequivocal. The glaciers of the Asian mountain range, which hold the largest quantity of ice outside of the polar regions, are shrinking by 1 percent each year, and that rate is accelerating. Even with a conservative estimate of 1.5 degrees Celsius (roughly 2.5 degrees Farenheit) of warming above preindustrial levels by the end of this century, more than one-third of Himalayan ice mass would be lost.

“But it will be much more, because the warming will be more,” said Schaefer, who has done field research in the Himalayas. “And if you warm the global temperature by 2 degrees, you’re warming more than that in the higher mountains of Asia, because the high altitudes warm more.”

The global community will have to deal with at least a foot of sea level rise as a result of this Himalayan thaw. But more than 1 billion South Asians who rely on glacial melt for agriculture, energy production, and potable water face far more dire consequences.

“Right away,” said Schaefer, “if you are there for the first time, it becomes clear that glaciers are not just some abstract tourist attraction, which they basically are in Switzerland, where I did my Ph.D. There, if you change the glaciers, it’s kind of inconvenient for some skiers. In the Himalayas, it’s a very dominant part of the environment, and as soon as the glacier changes, the entire habitat of the people living in downstream valleys changes.” The water supply is paramount. “At some point, you will be sitting with no water at all outside of the rainy season in the big Indian rivers like the Indus and the Ganges and the Brahmaputra. This will be an epic disaster if it happens.”

Richard Alley, the Penn State geosciences professor who has authored numerous assessment reports for the Intergovernmental Panel on Climate Change, said that, even without taking diminishing water reservoirs into consideration, future heat stress will be enough to make life grim for the people of South Asia and the world’s other tropical regions.

“It is very clear that poor people in hot places get screwed by climate change,” said Alley. “When it gets unexpectedly hot, people die. And that’s not really close yet in Anchorage. But it may be closer in Ankara. And it may be way closer in some of the big cities of India. And it’s miserable long before it’s fatal.”

Toward the end of our interview, Schaefer shifted to a more optimistic call for action. He highlighted the work of Columbia’s Earth Institute, one of many American academic centers making strides in communicating the urgency of the situation by promoting collaboration between earth scientists, economists, political scientists, and other researchers. It is not too late, Schaefer insists, to take concrete action to save humanity from the most catastrophic climate outcomes.

“We are at a point where the message is so clear that we really can transfer something robust to policy makers,” said Schaefer. “We have to do the best we can. Predict and transform – bring this message to the decision makers, and prepare them for what might come.”

Photo at top: Aerial view of Himilayan glaciers in Bhutan. (Included in Joerg Schaefer’s presentation at the Comer Abrupt Climate Change Conference)



By Austin Keating, Video by Tiffany Chen and Austin Keating, Nov. 22, 2017 –

Scientists take to the field to study rapid warming and cooling events in Earth’s past. They find clues in ice and rock, lakes and sediment across the globe. Rebuilding climate change patterns from the past enhances predictions for the future as human use of fossil fuels accelerates global warming.

Leading geologists and climate researchers shared their latest discoveries and new developments at the Comer Abrupt Climate Change Conference in southwestern Wisconsin this fall.

The Comer Family Foundation has supported climate science researchers for 15 years now. This year, scientists presented a wide array of new discoveries, such as looking at how heavy rainfall in California over the past year and years of drought prior to that are depleting snowpack that streams water into the region.

Researchers also presented new data on glacial melt in Greenland, as well as melt in the Bhutan region of the Himalayas, where the lower-elevation faces of glaciers are thinning as much as 10 feet per year, according to research presented at the conference by Joerg Schaefer of Columbia University’s Lamont-Doherty Earth Observatory. Sea level rise as Greeenland glaciers melt and strained freshwater resources for several countries due to thinning Himilayan glaciers pose major concerns.

See related stories:
Soil Microbes Eat Up Methane: Gas Released From Thawing Ice Will Have ‘Minimal’ Impact on Climate Change

Oceans Soak Up CO2 and Buffer Global Warming

PHOTO AT TOP: A visualization of aerosols in the atmosphere above China recorded by satellites in 2006. Human-sourced aerosols and other greenhouse gases coming from China are rising, and scientists at the Comer Conference advocated for policy action to curb the trend (Courtesy of NASA).

NOTE: Tiffany Chen and Austin Keating are Comer Scholars, a Medill scholarship program supported by the Comer Family Foundation to promote graduate studies in Science  and Environmental Journalism.



By Morgan Levey, Dec. 11, 2017 –

For Californians reeling from the deadly fires in Northern California and the Oroville Dam crisis that displaced thousands, the record-breaking precipitation levels last year may seem like a silver lining after more than five years of drought.

Yet it’s precisely these massive swings, from prolonged dry periods to extreme rain and mud slides that have increased the state’s vulnerability to environmental catastrophes, stressing water supplies and amplifying flooding hazards.

Taken in April 2016, this picture shows that the snowpack is well below the moss on the trees—typically a way to identify the average annual snow depth—with less snow at lower elevations. (Ben Hatchett)

Experts believe climate change and global warming are the culprits for this extreme weather and warn that warming is impacting the mountains most severely. One-third of California’s water supply comes from snowpack in the Sierra Nevada mountains and snowpack reservoir that builds up during winter is in rapid decline. The Sierra Nevada is a moderate-elevation mountain range, highly susceptible to rising temperatures that change the snow level, or the point at which snow turns to rain in the atmosphere during storms.

Climate scientists are finding that it’s not just warming temperatures that are causing the transition from snow to rain but also the altering intensity and variability of winter storms in the Sierra Nevada.

“It appears that the storms themselves are getting a lot warmer,” said Benjamin Hatchett, a hydrometeorologist at the Desert Research Institute in Reno, devoted to studying natural and human-induced environmental changes. According to a new paper published in the journal Water by Hatchett and a team of climate scientists, the combined effects of rising sea surface temperatures and warming background air temperatures make conditions more favorable for warmer and wetter storms landing in the Sierra Nevada. Prolonged periods of dry weather between storms only exacerbates the water resource problems caused by rainier winter storms. The rainier winter downpours cause greater risk of flooding and leave little snowpack to stream into the water supply during summer.

Ben Hatchett shows the impact of thinning snowpack for California water supplies, presenting at the annual Comer Abrupt Climate Conference this fall. (Morgan Levey/ Medill)

“The rule of thumb is a handful of good storms make up the bulk of your water year,” said Michael Anderson, California’s state climatologist in the Department of Water Resources. But the hope is that most of these storms bring snow that stays frozen through the winter. While 2017 did bring record-breaking levels of precipitation, its snowpack was nowhere near the record-setting snowpack levels in 1983, according to Anderson.

California’s state water resource infrastructure is woefully underprepared for this type of climate shift. And it’s not just California. Nevada  also relies heavily on water supplies from melting snow.  The snowpack essentially acts as a secondary reservoir for the states’ water management systems. “If you don’t have a snowpack then you don’t have that ability for that spring refill, or limited opportunity for it. It puts more pressure on the summer water management objectives,” Anderson said.

Hatchett analyzed recorded snow-level data over the past decade and discovered that the snow for winter storms has risen approximately 1,200 feet in altitutde in the atmosphere between the beginning and end of the last ten years. Meanwhile, since 1951, the snow fraction or percent of precipitation that falls in a given time as snow, has steadily declined by about three percent each year.

“Over 10 years that’s 30 percent less precipitation falling as snow, so that can make a significant impact on our water resources,” Hatchett said. The last 10 years has been the steepest decadal decline in snow fraction over the past 67 years.

A precipitation map of the Western United States showing an atmospheric river making landfall. This storm resulted in the Oroville Dam overflow, forcing almost 200,000 people to evacuate their homes. Hatchett’s paper shows how these kinds of storms have both extreme precipitation and high snow levels, which combined with warming sea surface temperatures, can favor rainier than average winters. (Ben Hatchett)

Since the Sierra Nevada is a maritime mountain range, it’s highly influenced by its proximity to the Pacific Ocean. A major component of climate change is warming sea-surface temperatures, making conditions preferable for atmospheric rivers, or long, narrow filaments of water vapor in the atmosphere that “favor wetter, warmer, higher snow-level types of storms,” Hatchett says. With increased evaporation potential from the warming, atmospheric rivers pick up energy and moisture across the ocean and make landfall with more intensity and variability.  

“In California, we actually see precipitation totals associated with atmospheric rivers that rival that of hurricanes in the southeast United States,” Hatchett added. What Hatchett and his team are discovering is that the rise in sea-surface temperatures correspond with changes to the structure of winter storms, forcing the snow level to higher altitudes in the atmosphere and making less of this precipitation fall as snow.

Amid background warming and drying, stronger and more frequent atmospheric rivers are projected for the coming years. “I think the last couple years might look like a window into the future where we can have these persistent, very dry and warm years and then we might have one just awesome super wet year,” Hatchett said.

Long periods of dry weather increase opportunities for evapotranspiration, creating stress for water management systems and reducing water availability as temperatures rise. What does this mean for Californians? Basically the warmer the weather gets, the more often the Sierra Nevada will experience prolonged periods of drought punctuated by moments of heavy precipitation.

Hatchett’s research is key in assisting state officials regulate reservoirs and flood control. Anderson said the Department of Water Resources is dependent on this data to forecast winter storms. “The better we forecast them, the better we can start managing water that we expect to come out of them. Either as snow or as rain.”

This is not just a West Coast issue. Globally, changes in the climate system will force infrastructure to adapt. “We’ve built an infrastructure for a world that is changing,” said Richard Alley, a professor of geosciences and associate of the Earth and Environmental Systems Institute at Pennsylvania State University. “We have counted on snow pack to be our reservoir. And now we’re not going to have it because it’s reducing. And this is true in the Himalayas and this is true in California.”

Photo at top: A snowless landscape is becoming the norm in Tahoe, as seen in this photo taken early in the 2017 season at Squaw Valley. (David Metres/Courtesy of Ben Hatchett)

Note: Morgan Levey is a Comer Scholar, a Medill scholarship program supported by the Comer Family Foundation to promote graduate studies in environmental journalism. 



By Tiffany Chen, Dec. 11, 2017 –

Climate change is an urgent threat linked to floods, drought and increasing heat waves.  While carbon dioxide emissions continue to rise, President Donald Trump pulled the United States out of the Paris Climate Accord meant to cap emissions and the temperature rise due to them. Scientists gathered at the Comer Climate Change Conference in southwestern Wisconsin this fall to share their latest research and emphasize the critical need to fight climate change now.

Scientists agree that cutting back carbon dioxide emissions from fossil fuels and the investment in renewable energies might provide a solution. We have many alternative technologies already.

But one country can’t fight climate change on its own, it requires collaborations and communication among nations, scientist, law makers and the public.

PHOTO AT TOP: Climate change scientists gathered at the Comer Abrupt Climate Change Conference this fall to share their latest research and their deep concerns for the future ahead. (Tiffany Chen/MEDILL)

NOTE: Tiffany Chen is a Comer Scholar, a Medill Scholarship program supported by the Comer Family Foundation to promote graduate studies in science and environmental journalism



By Tiffany Chen

The oceans have always held carbon dioxide (CO2) in their vast blue depths during glacial and warm periods throughout Earth’s history, breathing it in and out as the climate warmed or cooled. Scientists are now fishing for clues from the floor of the sea to reconstruct past climate events via ocean chemistry to better understand what’s coming in the future.

The oceans have been absorbing humanity’s steadily increasing CO2 emissions since the start of the Industrial Revolution, buffering the impact of climate change. If not for the oceans, the Earth would be in far more trouble.

Indicators from deep sea sediments reflect the ocean’s storage of CO2. The total amount of carbon in the ocean is about 50 times greater than the atmosphere, and 48 percent of the carbon emitted into the atmosphere by burning fossil fuels resides in the sea, according to NASA.

“The CO2 level is 80 to 100 parts per million (pCO2) higher during ‘normal’ interglacial periods relative to glacials,” said Allison Jacobel, postdoctoral research assistant in Earth and Environmental Sciences at Columbia University.  “The question is, where did the CO2 go during glacial periods?” The leading hypothesis is that CO2 was stored in the ocean where gases dissolve. The atmosphere and ocean exchanges CO2 until an equilibrium is reached.

Atmosphere and ocean CO2 cycling pattern. (National Oceanic and Atmospheric Administration)

Jacobel studies uranium in seabed sediments. Uranium in the ocean is well-distributed and soluble, but when there’s a shortage of oxygen in marine sediments, uranium precipitates into a mineral form of reduced uranium and that’s how scientists know oxygen was lower and CO2 concentrations were higher in the ocean at a given time when the sediments were deposited.

Alison Jacobel of Columbia University

“It’s an indirect way to know [what] concentration of oxygen in the ocean was like,” said Jacobel, who preented her research at the Comer Abrupt Climate Change Conference this fall in southeastern Wisconsin. “We exhale CO2, and we take in oxygen, and so we sort of have an inverse relationship between how much oxygen there is and how much carbon there is.” Her studies suggest that the glacial carbon is stored in North Pacific deep water.

“We’re trying to explore how the Earth’s system works, how it behaves, what its natural variability is,” said Jerry McManus, professor of Earth and Environmental Sciences at Columbia University. “That won’t give us all the answers to what’s going on today, but it gives us a better understanding of the various interactions.”

McManus studies the accumulation of calcium carbonate (CaCO3), a crucial building block for organisms to form their shells in the ocean, and a climate change indicator. Calcium carbonate is part calcium and carbon and so it plays an important role in the carbon cycle of the Earth.

Calcium carbonate contributes to the ocean’s alkalinity, the ability of the ocean to neutralize acid. It is essential to the CO2 uptake of the ocean because the dissolved form of CO2 is acidic. “This property of the sea allows it to absorb a great deal of CO2,”  McManus said. “The calcium carbonate in solution is what holds CO2 from the atmosphere.”

Jerry McManus of Columbia University presents his latest reearch at the Comer Conference on the ocean’s uptake of carbon dioxide.

However, there is a catch.

Because the ocean has become more acidic since the industrial revolution, according to the Intergovernmental Panel on Climate Change (IPCC), the acidification causes more calcium carbonate to dissolve.This negatively impacts marine life with their shells made of calcium carbonate.. The warming and acidification of surface water also weakens the ocean’s ability to take up CO2 from the atmosphere.

“If we can determine natural variability, then we can determine whether [what] we’re doing now is really abnormal,” said Jacobel. “I think the consensus among scientists is that what we’re doing now has no parallel in Earth’s history.”

Photo at top: Ocean uptake of CO2 buffers the already high levels of the greenhouse gas in the atmosphere. (Medill photo)

Note: Tiffany Chen is a Comer Scholar, a Medill scholarship program supported by the Comer Family Foundation to promote graduate study of science and environmental journalism.



By Austin Keating, Nov. 22, 2017 –

Methane, a greenhouse gas frozen by the megatons in Earth’s melting ice, holds the potential to dramatically turn up the thermostat for the planet. But new research shows that a bacterial hero from Earth’s soils and seas will keep the thawing gas at bay.

Methane-eating soil microbes will prevent large plumes of methane from reaching the atmosphere as frozen deposits of it begin to thaw due to climate change, according to a paper in Nature recently published by Vasilii Petrenko and Jeffrey Severinghaus of the Scripps Institution of Oceanography at the University of California, San Diego. While Severinghaus doesn’t study microbes directly, he’s able to show their effect on past climates by going to Antarctica and sampling ancient air, he told colleagues during a presentation at the Comer Abrupt Climate Change Conference in southwestern Wisconsin this fall.

Scientists previously thought thawing methane deposits may have caused an abrupt 50 percent rise in atmospheric methane concentration during a rapid warming period at the end of the Younger Dryas, a cold period that ended 11,600 years ago. The prospect raised alarms for a potentially devastating climate feedback from methane, which molecule for molecule, traps at least 25-times more heat in the atmosphere than carbon dioxide.

Jeff Severinghaus

Through 10 years of sampling ancient air, Severinghaus, his graduate students and the rest of his team were able to show, however, that during the warming period, no detectable methane in the atmosphere came from thawed deposits.

They demonstrated this by looking at the radiocarbon content of 11,600-year-old Antarctic ice, exhuming a ton for each measurement at a precise and narrow vein of ancient ice originally deposited by snowfall on Younger Dryas glaciers. They gathered a corresponding control of modern-day air cleared of carbon-14 for each measurement as well.

Methane released from thawed deposits has no carbon-14, because it’s old and the radiocarbon content decayed long ago. But methane released from natural sources such as wetlands is fresh, and has detectable carbon-14. Carbon-14 builds up in the air and in all living organic things as cosmic rays bombard atoms in the atmosphere.

“If that 50 percent increase in methane concentration was actually caused by the tundra getting warm and burping out all of this methane, then the concentration of carbon-14 relative to the more abundant carbon-12 should have gone down by 30 percent,” Severinghaus said. “We should really see a huge signal if this idea is correct …and we don’t.”

He added that methane-consuming soil microbes at the time must have stopped most of the thawing methane from reaching the atmosphere—just as their oceanic cousins did when they ate 99.9 percent of the methane released during the Deepwater Horizon oil spill in 2010.

Wetlands, which belch methane when it rains, and other natural sources were the main culprits for the rise in methane during the Younger Dryas warming period, Severinghaus said.

“If it didn’t happen back then, it won’t happen now and it won’t happen in the future,” Severinghaus said. “We can focus our attention back on CO2 [carbon dioxide], which really is the problem, and not worry so much about methane. So check one thing off the list.”

Pennsylvania State Geology Professor Richard Alley concluded Severinghaus’s presentation by applauding the amount of work that went into the research.

“Jeff could stand up here and give five or six more talks that have come out of these samples, it’s just really spectacular,” Alley added.

See related story: Climate Scientists Rebuild the Past To Meet Current Climate Threat

PHOTO AT TOP: Vasilii Petrenko works in the Severinghaus lab, and went to Antarctica to measure radiocarbon in ancient glacial ice. This chamber melts the ice so he can capture and measure the methane content, as the ice traps air bubbles of the atmosphere as it existed 11,600 years ago during a rapid warming event.(Courtesy of Jeffrey Severinghaus)

Note: Austin Keating is a Comer Scholar,  a Medill scholarship program supported by the Comer Family Foundation to promote graduate studies in environmental journalism.


By Morgan Levey, Dec. 16, 2017 –

Elevation map of the coastline of Maine. (From glacial geologist Brenda Hall’s presentation at the Comer Abrupt Climate Change Conference)

We think of rising fossil fuel use and the resulting carbon dioxide emissions as key catalysts of climate change in today’s warming world. And changes in climate throughout Earth’s history had many drivers, including geological forces, orbital cycles, ocean circulation and a litany of planetary mechanisms that happen on a microcosmic scale. Now imagine that there is another way for Earth’s temperatures to rise rapidly – one we’re not aware of as yet beyond a few clues and one with the potential to amplify today’s global warming.

A little over 17,000 years ago, Earth was well past the peak of the last great ice age and the Southern Hemisphere had begun shifting into the warmer climate we know today. Globally, however, this was not the case. The North Atlantic was experiencing one of the coldest periods of time in the region’s history. Yet scientists are beginning to believe that, although winters were extraordinarily cold, summer temperatures might have been fairly mild in the North Atlantic during this time, warm enough that the ice sheet covering the region may have begun retreating. If that were true, new research suggests that a new mechanism exists, one with the capacity to quickly warm the entire globe at once, at least on a seasonal basis.

Brenda Hall presenting her research at the Comer Abrupt Climate Change Conference this fall. (Morgan Levey/ Medill)

“This is still under study, but our work indicates the end of the ice age may have been rapid,” says Brenda Hall, a glacial geologist at the University of Maine. Climate scientists such as Brenda Hall are urgently trying to put all the pieces together from the past to better predict where human activities may be taking climate now. She’s attempting to chronologically map the retreat of the North American glacial mass through Maine roughly 17,000 years ago in an effort to understand the mechanism that might have triggered warming in this area.

During the last ice age carbon dioxide was trapped in the depths of the Southern Ocean. When deglaciation began, normal ocean circulation resumed and the trapped carbon dioxide was slowly released into the atmosphere. But Hall thinks warming might have occurred so quickly that temperatures may have risen prior to much rise in carbon dioxide levels.

“This may indicate a reduced role for carbon dioxide in causing the warming [then], and it also indicates that another mechanism is present that can cause rapid global warming,” Hall says.

That doesn’t mean that carbon dioxide – driven by fossil fuel emissions to the highest levels in at least a million years – isn’t forcing global warming now. But this other mechanism Hall is investigating could turn up the thermostat even more.

A lineage of research

The impetus for Hall’s research in Maine started with her mentor, George Denton, her Ph.D. advisor in the 1990s. Denton is a glaciologist whose research for tracking glacial retreat has been so fundamental to the field that he has not one, but two glaciers in Antarctica named after him.

George Denton explores the important clues about abrupt climate changes revealed by the end of the ice ages. (2016/Medill Photo)

Denton, with fellow climate scientists Richard Alley and Wallace Broecker, and philanthropist Gary Comer, who supported widespread climate research, published a paper in 2005 based on fieldwork  they had conducted in Greenland. They had discovered an inconsistency in the annual temperature records preserved in physical characteristics of the past during the Younger Dryas, a period of moderate glaciation that started roughly 13,000 years ago.

Glacial geological fieldwork involved dating beryllium-10 isotopes found in samples of rocks taken from glacial moraines, lines of boulders that trace what was once the edge of glaciers and ice sheets, as well as boring ice core samples and dating the pockets of air trapped inside. From the moraines that Denton and the others were dating, the team learned that temperatures during the Younger Dryas were only shifting a few degrees. However, previously published data from ice cores bored recorded a much larger change of 15 degrees Celsius from the same area.

The Younger Dryas marks an era when the North Atlantic region was suddenly thrown back into a near-glacial state as the rest of the world thawed almost completely. Like the era Hall is studying, it was thought to be bitterly cold. The small shift in temperature recorded in the moraines led to the belief that varying temperatures between seasons could account for the ice core shift. While the winters in the region were frigidly cold, the summers may have been quite moderate.

Hall’s research

Hall began to wonder if seasonality was having an effect on ice sheets during other periods of extreme cold in the North Atlantic. Around 17,000 years ago Earth was warming and glaciers were melting from the Southern Hemisphere to the Swiss Alps. “And so that made us wonder, what about the ice sheets?” says Hall.

Hall recently presented her findings at the Comer Climate Conference in southwestern Wisconsin, an annual meeting of climate scientists who have received research funding from the Comer Family Foundation.

Hall’s work is in its infancy, as she gets the dates back from the lab and beginning to analyze her results. But her initial data is proving consistent with her hypothesis. The ice sheets were likely retreating.

Traditionally it is believed that the climate of the hemispheres is out of phase, driven by a bipolar see-saw mechanism, a roughly 1,500 year cycle based on ocean circulation where one pole warms and the other cools. The recorded prevalence of seasonality suggests another mechanism might be at play, one that also “would have to be able to affect the entire globe at once – at least in summer,” Hall says.

She acknowledges that this suggestion is highly controversial, but her initial findings are further confirmation of this. “The bipolar seesaw – if it exists – would only occur in the winter,” Hall says.

Climate scientists, suhc as Hall, map the warming and cooling trends that have occurred throughout our planet’s lifespan in an effort to track the causality of individual factors on climate changes. Earth is large, so a lot of this happens at the level of regions or continents. When a force affects the whole planet, it’s significant. And in today’s warming world, where we are driving carbon dioxide levels to unprecedented heights, it means that warming could be amplified by forces we are only beginning to discover, let alone understand.

The lineage continues

On the other side of the North Atlantic, Gordon Bromley, a glacial geologist and former student of Hall’s, is conducting similar studies – trying to chronologically map the retreat of the ice sheet – but through Scotland.

Gordon Bromley presenting his research on Scotland at the Comer Climate Conference (Morgan Levey/ Medill)

“We’re using exactly the same techniques, same philosophy as we approach it,” says Bromley who also presented his latest findings at the Comer Climate Conference. His results so far have matched Hall’s. “I was pleased to see the same signal, same recession, during the periods that we think our conceptual model says it should be retreating, that is happening on the west side of the Atlantic and on the east.”

Like Hall’s research, Bromley’s Scottish work is building upon previous evidence of global ice sheet retreats around the same period of time. “I’d say that Brenda’s New England work and our Scottish work both grew organically and quite separately from the same line of inquiry. That they are converging attests to the global nature of abrupt climate change,” says Bromley.

For Bromley and Hall, the similarity in results is encouraging, but the work is also tied to a legacy that both are proud to be a part of.

“The way that George trained Brenda and Brenda trained me – hopefully I can train my students that well. It’s like being part of the family business,” says Bromley.

Elevation map of the coastline of Maine. (From Brenda Hall’s presentation at the Comer Abrupt Climate Change Conference)

Note: Morgan Levey is a Comer Scholar, a Medill scholarship program supported by the Comer Family Foundation to promote graduate studies in environmental journalism.



By Adam Cohen, October 31, 2017 –

Richard Alley smiled widely, beer in hand, as he welcomed a group of student journalists to the annual Comer Climate Conference this fall. “I bet you all have a cell phone on you,” he said. “Don’t throw it on the ground!” The students exchanged sideways glances. “It might break,” Alley continued. “And that’s important. Things break easily.”

Things like the Earth.

Alley, professor of Geosciences at Pennsylvania State University, is a world leader among the contributors to discoveries about global warming and one of the scientific community’s master communicators. He has written five books, testified before various United States senate and house committees, and authored numerous assessment reports for the Intergovernmental Panel on Climate Change. Alley has devoted his career to conveying the fragility of the complex systems that keep our planet in balance. He now feels it is time for “reframing the discussion” to convince people of the urgency surrounding climate change.

In January 2014, C-SPAN broadcast live as Alley testified before Congress. At one point, the panel got on the topic of prehistoric interglacials – eras in which the Earth warmed without human interference. “Why did it happen then if these same factors that you’re blaming it on didn’t exist then?” asked Republican representative Dana Rohrabacher of California.

“The ice ages are caused by features of Earth’s orbit,” Alley responded. As he spoke, he put one finger on the top of his head (the North Pole) and one hand in front of his nose (the equator), illustrating the back-and-forth nodding of the orbit that happens over 41,000-year cycles. “We know what that’s doing right now, and it’s not [happending] fast enough to explain what we’re seeing.”

Richard Alley, a master communicator, being interviewed at the Comer Climate Conference in October. (Morgan Levey/Medill News Service)

That 30-second sound bite is the topic of the 500-page Earth: An Operators’ Manual, which Alley published in 2011. “More and more,” he writes, “the processes that made Earth’s landscape in the past are not the processes that students observe today, because the dominant processes today are ‘us.'”

The majority of the American public has finally gotten the message, thanks to the insistence of scientists such as Alley. A July 2017 survey conducted by the Yale Program on Climate Change Communication shows that 58 percent of Americans “believe climate change is mostly human caused,” while “only 30 percent say it is due mostly to natural changes in the environment.”

Though he will continue to try to popularize the science – his lesson in plate tectonics set to the tune of Johnny Cash’s Ring of Fire and posted on YouTube may be his biggest hit to date – Alley believes we should now devote more of our collective energy to convincing those who already understand the urgency of anthropogenic climate change to take action. Some have an ethical problem with “rich people in cold places burning fossil fuels and hurting poor people in hot places.” Others prioritize issues like national security and job creation, both of which would be positively impacted by good climate policy. Alley wants to consider each group separately and use targeted messaging to unite, rather than polarize. “Anything you can think of on this topic – all of them point the same direction,” he says.

Alley served as MC, as he does every year, at the conference held by the Comer Family Foundation in early October. He was a good friend of the late Gary Comer, founder of Lands’ End. Now, as one of the foundation’s science advisors, he helps make recommendations on awarding climate field research grant money from the foundation.

Moving around the airplane hangar where conference sessions are held on the Comers’ sprawling southwestern Wisconsin estate in a blue checkered button-down and wool slippers, Alley led the forum with his characteristically unyielding ebullience. “Grab your coffee, grab your chair – we have exciting science to do!” he said between talks on beryllium-10 moraine dating. (Beryllium-10 collects in the quartiz of ice-free rocks struck by cosmic rays once the glaciers have tossed them aside as they lumber away, offering a time machine for pacing the retreat of glaciers.)

At the end of day two, it came time for Alley’s closing remarks. He choked up as he wished his fellow scientists a fruitful year of discovery. “I love these meetings,” he said, his voice trailing off. “You have a voice because you’ve done the science.”

Photo at Top: Richard Alley in the field. (Photo by Karen Alley for the PBS series “Earth the Operators’ Manual)
Related story: Richard Alley talks about how fixing climate will be good for the economy.
Note: Adam Cohen is a Comer Scholar, a Medill scholarship program supported by the Comer Family Foundation to promote graduate studies in environmental journalism.


Carp caught at the event will provide data to develop water jets that can keep the invasive fish from moving upstream to the Great Lakes
By Austin Keating, Aug 31, 2017 –

(Austin Keating/Medill)

Photo at top: Some of the carp caught at Redneck Fishing provide research that can prevent the invasive species from entering the Great Lakes. (Austin Keating/Medill)

At the annual Redneck Fishing Tournament in early August, teams of Asian carp catchers unload their hauls into a semi-trailer full of the invasive, dead fish.

Most of the harvest went to cat food and fertilizer factories, but several dozen were taken by the U.S. Army Corps of Engineers for study in the battle to keep the jumping Asian carp out of the Great Lakes — where they could spread prolifically and ruin the area’s $7 billion fishing economy.

Carp caught at the tournament serve many functions. (Austin Keating/Medill)

Jan Jeffrey Hoover, a research fishery biologist for the U.S. Army Engineer Research and Development Center in Vicksburg, Mississippi, went to the Redneck Fishing Tournament in the small western Illinois town of Bath to take measurements from the larger carp caught at the event. These measurements will help the corps replicate their serendipitous success at blocking large numbers of Asian carp from the Upper Mississippi River.

“Because the water there is restricted through a series of gates [north of St. Louis], it comes out at a higher velocity — for a relatively short distance — but enough that it’s impeded the entry of Asian carp into the Upper Mississippi River. We can exploit that technology, and we can exploit that weakness in the carp’s biology, by replicating hydraulic conditions that mimic that flow,” Hoover said.

At Redneck Fishing, the race to net the most Asian carp in four separate heats resulted in a catch of more than 2,700 of the fish. The carp that elude capture continue up the Illinois River and are prevented from reaching Lake Michigan by an electric barrier.

Research fishery biologists Steven George (right) and Jan Hoover (left) take down measurements. (Austin Keating/Medill)

But the corps wants more precautions and recently requested $275 million from the federal government to install jets near Joliet to mimic flows seen in the Upper Mississippi. The corps already has a series of electric barriers in the Chicago Sanitary and Ship Canal, which connects to Lake Michigan. But despite their largely successful track record, a live Asian Carp was recently found just a few miles away from Lake Michigan, according to the the Chicago Tribune. It could have been carted there by a bird rather than jumping the barrier — scientists are unsure, Hoover said.

If funding is approved, the jet-enabled new layer of protection would have to be fine-tuned to keep out silver carp, a greater threat than the bighead carp, both of which are found in the Illinois and Des Plaines rivers, Hoover said. Silver carp, unlike bighead carp, jump when stirred by a wake and noise. They also occur in substantially larger numbers and have higher burst-swimming speeds than the bighead carp.

Both types of carp have gradually inched closer to Lake Michigan since flooding from fish farms in southern states introduced them into the Mississippi River in the late 1970s.

Finding the right water flow to impede Northern Illinois-adapted carp requires data on fish length and weight, which Hoover gathered at the event. He only picked the largest fish because they swim faster.

Having weight and length measurements for the fastest fish will allow the corps to develop maximum water velocities that prevent most carp from moving upstream.

Data are also gathered using water tunnels like this to evaluate swimming behavior and endurance at different water velocities.

Asian carp in a water tunnel. (Courtesy of U.S. Army Corps of Engineers, Engineer Research and Development Center)

Hoover also collected data that will be useful for lowering the count of Asian carp in Illinois rivers through other harvest events like Redneck Fishing.

“We’re collecting measurements on some of the fish they’re collecting here. And we’re dissecting them to look at their reproductive condition and the stage at which they’re reproducing,” Hoover said, adding that he also collected bones for age determinations and eggs to establish the number of offspring from individual females.

All of this can be incorporated into a harvest estimate through population modeling “to learn what rates of harvests would be useful in pushing … populations into a downward spiral,” Hoover said.

Bath — and its slice of the Illinois River — is a global hotspot for Asian carp. That’s why “harvesting events” like Redneck Fishing are so important. Not only does the yearly event help keep the population in this section of the river at bay, but it also gives scientists hundreds of fish to choose from for scientific study.

The weekend-long event in early August brings hundreds of tourists and locals to the small town with a population of about 300. Speed boats full of people holding nets follow pontoon boats that stir the carp with deep wakes, causing them to jump out of the water.

Racing to be the top carp catcher at the Redneck Fishing Tournament. (Austin Keating/Medill)

“Asian carp have a variety of impacts, not the least of which is public safety when they fly from the water and strike boaters. But more insidious are the environmental impacts that the species pose. Particularly in side-channels like this off of main-stem rivers like the Illinois and Mississippi rivers,” Hoover said. “Asian carp — once they get into a system like this — render it void of zooplankton. And that’s a food source for commercially desirable fish.”

Hoover added that his research is funded by the Aquatic Nuisance Species Research Program.

Lifelong Bath resident Robin Daniels has volunteered at every Redneck Fishing tournament since the extravaganza began 11 years ago. While they were able to fill a semi-trailer full of the fish, prior years had much larger harvests. The turnout this year was lower, and the water level was high due to rain — making the fish less likely to jump, she said.

“I don’t think the carp are as bad because, in previous years, they’ve caught so many,” she said. “I grew up on this river, boated on this river. I would have never thought of seeing a flying fish back in those days. So we’ve all experienced a big change in this area.”

See related story: How Tiny Bath on the Illinois River Turned an Invasive Species into a National Tournament.


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