climate change

The Sustainability Review Interview with Dr. Wallace Broecker

We at The Sustainability Review had the privilege to sit down with the oracular grandfather of climate science, Dr. Wallace (Wally) Broecker, Newberry Professor of Geology in the Department of Earth and Environmental Sciences at Columbia University. We consulted him for his thoughts on his work and on the past and future paths of sustainability science. What follows is an edited transcript of our conversation. The Sustainability Review (TSR): What started you looking into atmospheric carbon dioxide accumulation?

Dr. Broecker (WB): The first thing I worked on was carbon 14 measurements. The emphasis was on two things: dating of late quaternary events, and using it to get the rate of ocean circulation by measuring the age of the carbon in deep water. The latter lead me to be interested in the carbon cycle. Right now 25 or 30 percent of the CO2 we produce is going into the ocean; eventually that will increase to 80 percent or so, but only over hundreds of years. The way we know this is by measuring the radiocarbon distribution in the ocean. That got me hooked.

While I was doing my thesis, there wasn’t much talk about CO2. Then several papers came out in the late 1950s and Charles David Keeling started his measurement series establishing how rapidly CO2 was going up. This made it more interesting. Could we explain what was happening? We knew the amount of fuels burned and we knew the increase in the atmosphere. Interestingly enough if you put a curve through the measurements assuming that 57 percent of the amount of fossil fuels burned remained airborne, excepting a few fluctuations, it fits Keeling’s curve beautifully. So where was the other 43 percent?

TSR: Where did these efforts take you? Can you touch on having to testify before congress?

WB: The frustrating thing was that in those days, congressmen would want something in the congressional record…initially, you’d be told you had five minutes…which meant they would jibber-jabber around and you’d be cut down to one minute.

I was asked to testify in the 1980s and I learned enough to know that writing down something to present was useless because you probably wouldn’t be able to use it at all, so I decided I’d write something to be published in Nature (1981). It was published and it was the first warning about abrupt climatic changes.

TSR: You once discussed how you find something sacred about science and that you don't like to see findings "monkeyed with." Once knowledge is in the open, however, scientists lose control of the conclusions people make. How do scientists deal with that?

WB: I think that scientists have to be very honest. I’ve always been very honest; people respect me for that. When you start exaggerating to get attention—and a lot of environmental claims have been exaggerated—that just destroys your credibility. I’m guilty of that now and then, but I try not to be.

TSR: How do you approach your work?

WB: I’m considered an idea person. Probably the best feeling you get is when you discover something new. If I had to base my reputation on measurements, I’d be run-of-the-mill. But I’m clever at putting apples and oranges together and coming up with something interesting. That is my strength. I often wondered why I could do that. I’m dyslexic, so maybe that has something to do with it; my mind works differently. People at times have said they’re afraid to show me data because I have such a quick mind that I spot what it means. That’s my talent.

TSR: Taking a step back, we found a profile of you in The New York Times from 1998. It shared some of your thoughts about computers ‘short circuiting’ a researcher’s thinking about the workings of earth’s ocean/atmosphere systems and that a pencil, on plain white paper are your investigative allies of choice. Who are your sleuthing companions these days?

WB: I started all this way before computer simulations. We used what we called box models where you transfer materials from one box to another. We learned enough about how the ocean works to build a simple model. Then we would get to the point where this allowed us to shortcut—we’d been through a number of steps and so we could add new ones more much more quickly.

TSR: In conceiving of this interview, we had an analogy in mind: sustainability science today may parallel where climate science was 50 years ago.

WB: Well, they’re very different. What I was doing was hard science, and in a sense, that’s much easier because you’re trying to do something tangible. A lot of sustainability science is less well-defined, and here [at ASU] specifically it’s more like social science than hard science. Where I am at Columbia it’s more hard science than social science just because Lamont Observatory is so big it tends to dominate the research direction of our Earth Institute. We started a sustainability concentration for undergraduates four years ago, and now there’s a sustainability major. It took a while to get the committees at the university to agree, because there is always the suspicion that it’s too diffuse. But of course, it has to be.

TSR: How do you see climate science informing sustainability science and sustainability science informing climate science? Do you see those interactions happening?

WB: There has to be interaction. If somebody has a scenario about switching to a new energy [we need to know], how much will it cost? What I do could be called reverse engineering. Engineers design systems. We try to figure out the design of God’s machine, the earth’s systems. It’s complicated. Just to make a model of the atmosphere that includes cloud droplets is a tough chore. So we’re working to understand how this system operates and therefore, what will happen if we perturb it. We’re good at what’s called "back of the envelope" calculations. It’s very important to eliminate the easy things right away. We quantify. You have to have that, because everything we do is going to cost money, and everything we do is going to have environmental consequences.

What I see now is that the concern about environmental consequences is stalling many things that could be done about CO2. We must get away from that mentality because everything we do has environmental consequences. Also I get discouraged when I see people competing. I was asking Klaus Lackner, my hero, why people are so antagonistic toward his idea that you can take CO2 out of the air. He said there are lots of reasons, and one is that there’s a large group of people who want to re-fit power plants and of course that would take huge profits. So they don’t want air capture. That’s insane; we must do both. One will prove to be cheaper and environmentally less objectionable and that one will win out. That’s the way the world runs.

TSR: You once noted, "No one lives on their past successes…It isn't very satisfying. You live on what you're doing this year, this month. My great joy in life comes in figuring something out. I figure something out about every six months or so, and I write about it and encourage research on it, and that's the joy of life" (1). What are you working on now?

WB: One is what I call the Mystery Interval. Twenty-five thousand years ago the carbon 14 content of the carbon in the atmosphere and upper ocean was 40 percent higher than now. That stunned us. By dating corals using uranium series isotopes, the radiocarbon signature content can be turned, making it possible to calculate back to what it was initially. In many different kinds of samples, it was shown to be 40 percent higher. Now we’re trying to figure out why that was. The only way we can explain it is that during glacial time the ocean was stratified—instead of mixing the radiocarbon through the whole ocean, it was mixed only through the upper part, while in the lower half radiocarbon was decaying away. Because of this the upper half in the atmosphere would have more radiocarbon and the lower half would have less, and then at the end of the glacial period these two reservoir were mixed together.

The other thing I’m working on is paleohydrology—using stalagmites and closed basin lakes—to say something about moisture history. Fifteen thousand years ago, during part of the deglaciation, the water cover in the great basin—Oregon, Utah, Nevada—was ten times more than today. That means there had to have been somewhat less evaporation, but also seven or eight times more water coming down rivers. That’s amazing. And there was probably only two times more rainfall. This wet period lasted hundreds of years, and then there was a millennial duration drought that cut the water availability to less than today’s.

We found that these changes are globally orchestrated. The thing that interests me is that what happened 15,000 years ago had to do with a shift caused by a southward shift in the location of the thermal equator. When the northern hemisphere was cooled by extra sea ice this shift made huge and abrupt hydrologic changes.

Climate change models say that as CO2 rises the northern hemisphere will heat twice as fast as the southern hemisphere. The reason is that there’s more ocean in the southern hemisphere—it will hold back the heating. This is going to shift the thermal equator. So the question is, will that produce similar effects to the shifts we see in closed-basin lake records? If so you Westerners are in bad trouble. However, what’s happening today is not the same as the previous shifts. One was induced by sea ice and the other was induced by differential CO2 warming. There are differences. Maybe the differences will cause what happens to be very different.


Occupy Creation!: The Role of Religion and Ethics in Addressing Climate Change

By Rev. Doug Bland Standing on the steps of the Newman Catholic Student Center across the street from ASU’s campus and the Global Institute of Sustainability (GIOS), Rev. Jan Olav Flaaten told the story of climate refugees in the Pacific island nation of Tuvalu.  As he recounted the story of rising sea levels, Flaaten grasped the blue shower curtain that encircled him and slowly raised it from his knees to his waist to his chest.  He finished the story with only his nose sticking above the rising cloth waves.

The "Moving Planet" march on September 24, 2011, at which this dramatic recitation occurred, was co-sponsored by GIOS and Arizona Interfaith Power & Light (a coalition of religious communities concerned about climate change). It happened because Lauren Kuby of GIOS brought sustainability students and staff together with people from the faith community.  Rev. Flaaten, Executive Director of the Arizona Ecumenical Council, was one of several religious leaders who facilitated the event.

The "Moving Planet" march united people of faith with those who claim no religious affiliation in a walk from the Newman Catholic Center to the Tempe Mosque to the Hillel Jewish Center and finally to the First United Methodist Church.  At each stop we told stories of some of the world’s environmental refugees, including the forced migration of the Bog Copper Butterfly populations, disappearing glaciers, and refugees from Ethiopia’s drought.  We honored the suffering, mourned the losses and shared confessions of our own complicity.

Religion and spirituality are some of the most significant influences on environmental values—both good and ill.  Lynn White Jr. famously argued that Western Christianity "bears a huge burden of guilt" for the contemporary environmental crisis.  He went on to explain: "What people do about their ecology depends on what they think about themselves in relation to things around them.  Human ecology is deeply conditioned by beliefs about our nature and destiny—that is, by religion" (1).

Today, religious communities are increasingly providing resources and teachings to affirm and deepen environmental ethics.  Whether in the Vatican’s bid to become the world’s first carbon-neutral state, the host of environmental policy statements generated by religious denominations, the embrace of "creation care" by evangelical Christians, or the rise of faith-based environmental organizations, religious worldviews are being applied as never before to help solve environmental problems and preserve ecological integrity.

Just as healthy religion fosters healthy ecology, noxious religion fosters noxious ecology.  For the environment, the most menacing religion of them all is the Materialism and Consumerism of western civilization.  One of the reasons that our culture is so impervious to the scientific data that verify anthropogenic climate change is, at its core, religious.  As a society, regardless of our stated creeds, we are inclined to idolize the same bottom line that Exxon worships.

Frank conversation about climate change has stalled because we keep debating whether climate mitigation makes economic sense (jobs, jobs, jobs) and whether the scientific evidence for anthropogenic climate change is settled.  We need to ask deeper questions: ethical questions, religious questions. Questions investigating why we have developed ethics for suicide, homicide and genocide, but not for biocide or geo-cide (2).

At the most fundamental level, climate change is not a scientific, political, economic or energy problem.  It is a moral and ethical crisis.  Our energy use and consumption threaten life as we know it.   Solutions won’t come simply by stacking up more scientific facts or technical arguments.  From civil rights to women’s suffrage, history has shown that toxic pieties, practices and policies can be overcome only when they are recognized to be morally wrong and decidedly unjust (

We need a religious and ethical revolution.  Occupy Creation!  Let the human 1 percent listen to the flora and fauna of the 99 percent.  As the writer of Job suggests, "Ask the animals, and they will teach you, or the birds of the air, and they will tell you" (Job 12:7).

Gus Speth, Dean of the Yale School of Forestry and the Environment said, "Thirty years ago, I thought that with enough good science, we would be able to solve the environmental crisis.  I was wrong.  I used to think the greatest problems threatening the planet were pollution, bio-diversity loss and climate change.  I was wrong there, too.  I now believe that the greatest problems are pride, apathy and greed."  Speth called for "a cultural and spiritual transformation" and admitted "we in the scientific community don’t know how to do that" but religious teachers do (3).

As a religious leader in our community it is my intention to be part of the sustainability dialogue that GIOS helps to foster.  Learning to live sustainably is not just the work of the "The Great American University"; it is "The Great Work" (4) for all of us, and it is Holy.


1. White, L (1967) The Historical Roots of the Environmental Crisis. Science 155: 1203-1207.

2. Rasmussen, L (2010) An Earth-Honoring Faith. Sojourners. June 2010.

3. Richard, C (2009) "What If?" in  Love God Heal Earth, ed. Bingham, SG (St Lynn's Press, Pittsburgh, PA), pp 9.

4. Berry, T (2000) The Great Work: Our Way into the Future. (Harmony Books, New York).

Contributor’s biography

Doug Bland is Pastor of the Tempe Community Christian Church.  He serves as Executive Director for Arizona Interfaith Power & Light and teaches storytelling classes at South Mountain Community College.

Coral Reefs in Crisis: Finding Nemo May Become a lot Tougher

By Tara Haelle If your food sources vanished tomorrow, how long would it take you to starve to death?

What if your diet until this sudden starvation already lacked the nutrients to keep your bones strong and healthy? What if you were already suffering from the flu, or a more serious disease? It's impossible to say definitively how long your starving, weakened, diseased body would hold out, but death would be knocking.

Such is the state of our coral reefs today. The triple threat of coral bleaching (which causes starvation), higher prevalence of disease and more acid in the ocean (inhibiting corals' skeletal growth) calls into question how long our reefs can continue to survive. Or, at least how long they’ll look as we envision them in our Jacques Cousteau-inspired imaginations: gorgeous orange and yellow fans waving beside barrels of purple and bowls of blue, with Nemo and friends darting throughout the nooks and crannies that house the crustaceans we order at Red Lobster.

We must remember the brooding fact that this ecosystem’s decline contributes to ours as well—unless we act. The public needs better media reporting and guidance to address the problem; we lack both at the moment, but both can be remedied.

Thousands of miles of coral reefs are starving; many will recover, but in their weakened state, they’ll become more susceptible to the diseases proliferating as sea surface temperatures rise. Since coral is, literally, the bedrock of marine ecosystems, this situation signals trouble for oceanic life and people.

Coral reef degradation is the proverbial canary in the coalmine. Not because reefs themselves will vanish one day but because the ways global warming, pollution and habitat destruction are affecting the reefs forewarn of the changes that will eventually reach our backyards—literally. Yet the complexity of these problems makes it a struggle for scientists to pinpoint what will happen first, when, where and how. It's like playing Whack-a-Mole on a football field littered with land mines.

"As you remove certain portions of the coral reef environment, the rippling effect starts occurring and before long some species, whether we like them on our dinner table or in our aquarium, will start disappearing," said Billy Causey, Southeast Regional Director of NOAA Office of Marine Sanctuaries. "In 50 years, we're going to be in serious trouble if we don't make some changes. We're going to see losses in coastal and marine environments, perhaps, even failures in fisheries stocks and so on."

Those losses translate into economic casualties as well. Ross Hill, a marine biologist at the University of Technology in Sydney, Australia, quoted one study that puts the number of people worldwide directly or indirectly relying on coral reefs at 500 million. That's half a billion people who could lose their livelihoods. While dying coral reefs might feel remote in the dead of a Minnesota winter, the worldwide financial collapse of 2007 painfully revealed how interconnected the economies of our world now are. The ripple effects of an economic crisis in a nation like Fiji—surrounded by coral reefs—matter to us in the U.S.

"You don't want the millions of people who live in low-lying areas of the tropics to end up as ecological refugees as the coral reefs die and the income from tourism and their food disappears," said Judy Lang, the Scientific Coordinator of the Atlantic and Gulf Rapid Reef Assessment Project.

Yet potentially irrevocable changes in coral reefs could lead to these consequences if we don't address the causes of coral bleaching, disease and ocean acidification. With the situation so dire, why isn't the message getting across? And what can we, many of us far from a coastline much less a reef, do about it?

The first answer is twofold: one, the media does a poor job of explaining what's really going on and what to do about it; two, it's hard to motivate people about issues so seemingly remote, in both miles and years. Reporters must clearly explain what's causing the degradation of our coral reefs and why it matters.

Let's start with causes: 99 percent of marine and climate scientists agree the number one cause of all three attacks on coral reefs is climate change from increased levels of carbon dioxide in the atmosphere. But as Ray Hayes, a member of the Global Coral Reef Alliance Executive Board and Professor Emeritus of Howard University College of Medicine, points out, "To look at elevated temperature as a sole causative agent [of bleaching] would be a mistake." Additional stresses on coral include land-based sources of pollution, habitat loss and overfishing.

Meanwhile, the ocean has been absorbing more carbon dioxide from the atmosphere and converting it into carbonic acid, weakening the ability of corals, crustaceans and mollusks to build their skeletons and shells. The cumulative effect on the reef resembles our own bodies' reaction to excessive stress: "The corals are overly stressed and diseases start breaking out," Causey explained. Indeed, diseases have proliferated in the past forty years, according to Lang.

"Bleaching," so named because the coral turns bright white, occurs when stressed coral expels the food-producing algae that contribute to its vibrant colors. Increased water temperature can trigger bleaching: coral-algae symbiosis flourishes in 78 to 86 degrees Fahrenheit; even a few degrees higher can spark a bleaching event. Sustained bleaching is essentially starvation, during which coral halts all inessential biological processes, including reproduction and skeleton-building, to conserve energy. Too often, bleached coral dies, and within hours brown, green and red algae grow over its skeleton, potentially preventing coral re-growth and, irrevocably, altering the reef environment.

"Coral reefs are nurseries for a number of economically significant seafood sources, such as lobsters and crabs and shrimp," Hayes said. "All those organisms we think of as being nutritionally supportive to a human population could be at risk as the reefs change."

In 1998, during the worst worldwide bleaching event on record, sixteen percent of the world's shallow-water reefs died. During another bad bleaching event in 2005, 80 percent of Caribbean coral bleached and as much as 40 percent died in the eastern Caribbean. According to Tom Goreau, president of the Global Coral Reef Alliance, 2010 was the hottest year in history—and one of the worst coral bleaching years ever. Goreau said he watched almost all the corals in Thailand die over the course of a few weeks.

Again, where are the screaming headlines to wake people up?

First, it's hard to personalize something like bleaching that’s only visible underwater at certain times of the year. Ocean acidification, Causey points out, presents a tougher hurdle: "We're not going to see ocean chemistry changes; we're just going to see the results after it's almost too late."

Kris Wilson, an environmental journalism professor at the University of Texas at Austin, said reporters must "transcend the journalism of proximity," a major factor in what gets reported. "A journalist has to take something abstract and bring it to a level to feel it's a part of their readers' lives," he said.

For example, telling readers about drugs like Ziconotide—a cone shell product recently approved as a non-addictive painkiller and used to treat Alzheimer's disease, Parkinson's disease and epilepsy—emphasizes the value of oceanic ecosystems. "A whole heap of medicines come out of animals that live on reefs," said Hill.

Yet, said Lang, we exacerbate the hazards reefs face with our high-energy consumption and with waste ranging from pharmaceuticals and fertilizers to household products and caffeine.

Another flaw in coral reef reportage arises from fundamental differences between scientific thinking and journalistic storytelling. The scientific method requires scientists to accept uncertainty in much of what they do; even gravity is still a theory.

"Science is long-term, incremental, always evolving," Wilson said. "Scientists are very cautious about their findings." But reporters and readers often want certainty and immediacy—rarely compatible with an issue like climate change. "We have to become comfortable with a certain level of uncertainty and still be willing to act," Wilson said.

According to Causey, this culture clash even affects how scientists talk to reporters. "It makes them reluctant sometimes because they think it's going to taint their scientific credentials if they go beyond what is or is not certain," he said. "We can't remain in stalemate because people are afraid of speaking beyond what they're certain of."

Most regrettably, however, reporters often leave readers feeling powerless: artificial he-said-she-said stories belie scientific consensus on the issue, or reporters sound doomsday trumpets without informing readers how to take action.

A reliance on "objectivity" over "balance" can distort how readers understand an issue. "Objectivity," the classic "he-said-and-she-disagreed" model Wilson describes, only presents two opposing points of view on a topic. "Balance" puts those views in context, quantifying and qualifying the voices on both sides.

Wilson adds that context is essential. "If a person is an outlier," he said, "you're obligated to tell readers the weight of his opinions." Wilson points out that prominent global warming skeptic Patrick Michaels receives funding from Western Fuels Association—this doesn't invalidate his opinions but it's essential to disclose.

"The more information people have, the more they realize these stories impact them, the more they'll hopefully become involved," he said. "Good environmental reporting has the potential to improve public policy and get people to understand their role in the environment and that they can really make a difference."

Of course, people must want to make a difference. "Most people are very myopic," Hayes said. "They see what's right in front of them and respond to the immediate situation and not to something that might be in the distance or somebody else's problem as they see it."

But time for them to notice is running out.

"What's happening to coral reefs is a preview of what's going to happen on a much larger scale," said Causey. "People need to recognize that although this may be happening in the tropics right now, it's not long before it's going to happen here. The coral reefs are symptomatic of the bigger climate change problems."

Hill adds that we must understand our place in the world. "We need to realize that humans are part of the global ecosystem, not above it and not immune to the effects we have on it," he said. He quoted Jacques Cousteau: "For most of history, man has had to fight nature to survive; in this century he is beginning to realize that, in order to survive, he must protect it."

Contributor’s Biography Tara Haelle is a photojournalism graduate student at the University of Texas at Austin and a high school journalism teacher at Texas Virtual Academy. A freelance writer and photographer in over two dozen publications, she primarily reports on health and environmental issues. As an avid scuba diver, she has a special place in her heart for sharks and coral reefs.