The Antarctic ice sheet is falling into the ocean, $1.1 trillion of investments are at risk due to a carbon bubble and the U.S. President is saying climate change is already affecting his country — by all accounts, you'd think the debate over global warming would be settled once and for all.

Yet it rages on. Recent polling shows public concern over climate change has fallen in Canada, the U.S., Britain and Australia over the last several years.

If there’s agreement among the world’s experts, why on earth is their disagreement among the world’s non-experts? And why is that disagreement so deeply polarized?

In a recent public lecture about polarized public discourse, DeSmog Canada founder and president Jim Hoggan posed the question: “Why are we listening to each other shout rather than listening to what the evidence is trying to tell us?”

This is not a rhetorical question.

This type of question, however, does tend to be posed rhetorically, perhaps with your hands being thrown up in desperation, moments before walking away. But it’s a question that matters, because so long as we’re just shouting at one another, we fail to make progress on the world’s big issues.

So let’s take the question seriously — it deserves it and it just might get us somewhere.

Cultural cognition: we're all running in cultural packs

Sometimes, arguments aren’t really at all about what they appear to be about. So-called "debate" on environmental or economic policy, for example, can at times be more about articulating competing perspectives than it is about "debating" how we might make progress on important issues.

"Debates" like this can (and arguably do) remain on an entirely superficial level.

But if we’re not engaging in real dialogue, then what are we actually doing?

According to experts at Yale University, we’re engaging in the practice of “cultural cognition.” Simply put, cultural cognition refers to our tendency to conform our beliefs to the cultural packs that we run with. What we might be doing in a “debate” is actually articulating the position our cultural group has on an issue.

This becomes really interesting, according to the folks at Yale, when we’re looking at issues of scientific consensus — that is, issues that aren’t really up for debate.

Debates are as much about culture as about science

Climate change, the disposal of nuclear waste and gun control are all contentious issues that rely heavily on scientific research. Yet, these issues are also largely cultural, and of significant political importance. They tend to be issues for which there is high scientific consensus and low public consensus.

So, how can we better understand the deep running undercurrents of cultural polarization that happen as a result of "cultural cognition?"

According to Dan Kahan, a Yale law and psychology professor who works on the university's cultural cognition project, we’d need to explain how we develop our viewpoints, not based on the research of experts and scientists, but in response to our community, as a means of identifying with our social group.

In a recent paper, "Cultural Cognition as a Conception of the Cultural Theory of Risk," Kahan and his colleagues outline how individuals develop opinions on scientific matters by identifying trustworthy experts. But just who passes the test of being a trustworthy expert varies widely between groups with opposing worldviews.

“We hypothesized that scientific opinion fails to quiet societal dispute on such issues not because members of the public are unwilling to defer to experts but because culturally diverse persons tend to form opposing perceptions of what experts believe,” the report states.

Overall, this leads to a sort of group-think confirmation bias.

“Individuals systematically overestimate the degree of scientific support for positions they are culturally predisposed to accept as a result of a cultural availability effect that influences how readily they can recall instances of expert endorsement of those positions.”

A little more plainly, this means that sometimes we’re a little overzealous in our endorsements of those we like. If the right person says it, we’re a little too quick to listen. If it came from "our side," we’ll tone down the criticism.

We listen to the science — when it agrees with us

And it gets more interesting. Kahan ties the tendency to agree or disagree with scientific consensus into deep and opposing worldviews. He divides these into two basic camps: those holding "hierarchical and individualistic” views and those holding “egalitarian and communitarian” outlooks — more or less the groups falling on one side or the other of the left-right divide.

But, even more interesting than that, there was no argument to be made that groups on the "left" were any better at discerning scientific consensus than groups on the "right."

As Kahan’s team found, both groups diverged from scientific consensus and expertise (scientific opinion endorsed by the National Academy of the Sciences) “in a pattern reflective of their respective predispositions.”

It turns out, “both hierarchical individualists and egalitarian communitarians are fitting their perceptions of scientific consensus to their values.”

That means taking a stand on issues like environmental policy is more a matter of personal identification than scientific “fact.”

For this reason, our belonging to a group (which, of course, we all do) can be problematic. We might buy into a group’s entire ideological system, rather than retain an open and nuanced view of a contentious political issue.

Maybe hold off on drinking the Kool-Aid

And, to make matters worse, groups often have internal inconsistencies. And what happens then, when we’ve drunk the Kool-Aid and have adopted a wholesale perspective on an issue, instead of recognizing that a single group can be right on some things and wrong on others?

Advocating for any given environmental policy shouldn’t have to mean you immediately agree with every other supposedly progressive grassroots opinion emerging from that group.

That’s an important distinction: you can say one thing, without saying all those other things. You can advocate environmental policy change without joining the entire club.

Why does that matter?

When we think of polarized debate, we picture opposed extremes talking past one another in a state of logic schism. Two groups, missing one another’s point, and depicting one another in an adversarial light.

How much of your thinking is done for you?

But there is another side to polarization. It’s not just about the two sides repelling one another; it’s also about what happens to each side individually. And it’s about us, as individuals.

The issue is one of how the individual sits within group mentality. Clearly, we share both a cultural and evolutionary propensity for grouping ourselves together. This has, and continues to, serve us well in many regards. But group mentality has a particularly adverse effect: if you’ve already decided which side you’re on, then a lot of your decisions are already made.

A lot of your thinking is done for you.

So, back to that original question: “Why are we listening to each other shout rather than listening to what the evidence is trying to tell us?”

It’s not just because two sides are talking past one another. The problem with this image is that, in it, we fail to take responsibility for our own shortcomings, as if we were saying: "We’re right, but they’re just not hearing us!"

The challenge of overcoming “cultural cognition,” then, lies in our intentional open-mindedness and also our careful communication.

Keeping an open mind is for our own sake: so our thinking doesn’t become stagnated, so that we can remain open to those big ideas when they finally come to us.

If current climate science is any indication (and yes, we’re aware that we’ve chosen to identify with the world’s most prominent scientists), the stakes are high.

Photo: Screen grab from Last Week Tonight with John Oliver (HBO): Climate change debate

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After the release of the latest Intergovernmental Panel on Climate Change (IPCC) report, professor Sheldon Solomon, experimental social psychologist and co-creator of ‘terror management theory,’ suggested human responses to news of impending social and ecological collapse have nothing to do with climate science and everything to do with death.

The prospect of violence, drought, famine and species extinction – all prominent aspects of the recent IPCC report – force individuals to confront feelings of mortality which we try to suppress by doubling down on our cultural worldviews. That means our own fear of death makes us more likely to strengthen and affirm our belief systems. So if you already don’t agree with climate science, the latest IPCC report isn’t likely to change that.

In fact, says Solomon, it’s “tough to get people to dispassionately and rationally consider the facts.” This may actually be more true for “very educated and scientifically literate people,” he says.

“I say that for two reasons. One is what psychologists these days call motivated reasoning, and there’s a whole set of studies suggesting people tend to view this kind of information in ways that confirm and fortify their preexisting beliefs. And so folks that are pro-environment will be apt to uncritically embrace these facts and become more ardently so and climate change deniers will discount them by generating counter arguments and disparaging the credentials of the scientists who produced the report.”

The second reason, he says, has to do with our human response to fear-inducing information, what Solomon studies under a rubric he calls terror management theory.

“This kind of information is daunting,” Solomon says, “because it conjures up both conscious and non-conscious reactions to the fact that we will some day die.”

Solomon points to one of the basic arguments made in Ernest Becker’s book the Denial of Death: “humans share with all forms of life a basic predisposition towards self-preservation in the service of survival and reproduction.”

But beyond the drives of other creatures, humans have the unique capacity to think abstractly and symbolically, he says, leading to a sense of self-consciousness. We can also reflect on both our past and our future and this, “makes us aware that we can die some day and that our death can come for reasons we could never anticipate or control.”

Such reflections can lead to “unwelcome realizations” that “give rise to paralyzing terror that we assuage through the development and maintenance of cultural worldviews.”

Ultimately, Solomon says, in these moments of terror we want to tell ourselves that we participate in and are valuable members of “a meaningful universe.”

This desire, to position ourselves within a meaningful universe, can have undesirable consequences, however.

When confronted with the looming image of our mortality, we usually end up doing one of two things: “One is to just get the images of death out of our minds. We tend to do that through suppression and distraction: watching television, consuming massive amounts of drugs and alcohol, going to Walmart to save a buck on a chainsaw and a lemon."

He added, "the Danish philosopher Kierkegaard called this being ‘tranquilized by the trivial.’”

The other involves constructing defenses – especially ones that affirm our worldview – that keep unwelcome thoughts of death from coming to mind.

“This has to do with bolstering faith in our cultural worldviews. So we may become more devoted to our career, more supportive of charismatic political leaders, even more concerned about the success of our favourite sports team.”

Ultimately a terror management theory perspective would suggest we need to “create conditions that will make people more receptive to dispassionately considering the facts,” Solomon says.

We can do this by “undercutting motivated reasoning and helping folks recognize how efforts to deny death can foster maladaptive defense reactions.” If we can anticipate our own desire to do away with unwelcome thoughts, perhaps we can find more productive ways of coping with our anxieties.

The recognition of our own death denial is the first step to confronting it: “I think if we can do that we can nudge folks in a productive direction.”

Yet there is still a significant barrier to overcoming inaction on issues like climate change: political polarization.

“We’re going to have to kind of go to extraordinary lengths to depoliticize these issues,” he says.

The thing to remember, according to Solomon, “is that left and right are both beside the point.” Open-mindedness and compromise, from both sides, may well be the only own avenue out of our current political deadlock.

“Conservatives might have to acknowledge, as Naomi Klein points out, that there may not be market solutions to these kinds of difficulties. Liberals may have to consider, as Stewart Brand points out in his book Whole Earth Discipline, that there might be a role for nuclear power and genetically modified foods in constructive solutions as we move forward.”

The challenge is to overcome the denial that prevents us from having these important – even if difficult – solutions conversations in the first place.

Image Credit: Jeffrey Smith via Flickr

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To overcome polarization on the issue of climate change, Yale professor Dan Kahan says in an interview with e360, scientists and the media need to frame the science in ways that will resonate with the public. A message that makes people feel threatened, he says, simply will not be effective.

By Diane Toomey

It’s a common refrain: If people only knew more about the science, there wouldn’t be so much polarization on the issue of climate change. But Dan M. Kahan’s groundbreaking work has gone a long way to prove that idea wrong. In fact, he’s found, it’s not the lack of scientific understanding that has led to conflict over climate change, but rather the need to adhere to the philosophy and values of one’s “cultural” group.

Kahan, a professor of law and psychology at Yale Law School, says “individualists” — those who believe individuals should be responsible for their own well-being and who are wary of regulation or government control – tend to minimize the risk of climate change. On the other side, he notes, those who identify with the “communitarianism” group favor a larger role for government and other collective entities in securing the welfare of individuals and tend to be wary of commercial activity – he sees them as likely to favor restrictions on greenhouse gas emissions.

In an interview with Yale Environment 360 contributor Diane Toomey, Kahan maintained that in order to break down this polarization, the issue needs to be reframed in a way that minimizes the likelihood that positions on climate change will be identified with a particular cultural group. “Are there ways to combine the science with meanings that would be affirming rather than threatening to people?” he said. “I think if somebody believes that there just aren’t any, I think that person just doesn’t have much imagination.”

Yale Environment 360: It’s been conventional wisdom in certain circles that people who discount the threat from climate change are not scientifically literate – they just don’t understand the evidence laid in front of them. But your research shows that this is not the case. In fact, polarization on climate change can actually be chalked up to which cultural group you belong to – “individualism” versus “communitarianism.” What do these opposing groups believe, and what does that have to do with one’s belief, or not, in the threat of climate change? 

Dan Kahan: The groups are defined by their shared understandings of how society should be organized. People who are more individualistic believe that individuals should be responsible for securing conditions that enable them to flourish without assistance or interference from any kind of collective authority or entity. People who are more communitarian think the collective is responsible for securing the conditions for individual well-being and sometimes should be able to take precedence over the interests of individuals if there is a conflict. People who are more individualistic are going to be more disappointed to believe that the consequences of activities that they like, such as a lot of commercial market activities, are creating harms that you would have to restrict. But if you believe that people who are engaged in commercial market activities are generating lots of inequality, it would be congenial for you to believe that this activity is really dangerous and ought to be restricted. 

So part of the theory is that people have a predisposition, based on their values and emotional engagement with the information, to understand it in a certain way… It’s important to recognize that that’s how people get any kind of information relating to science. People need to accept a lot more about what is known to science than they could possible figure out on their own. They are going to be looking to people like themselves, whose outlooks they share. 

e360: But we are talking here about a scientific question. Are you saying that people look toward scientists that they perceive are “like them”? 

Kahan: Most of the things that people are making informed decisions about that depend on science are not going to be ones they have consulted scientists for information about. Most of what people know – the decisions they make that are informed by scientists – is based on information that is travelling through all kinds of intermediaries. Scientists aren’t on television giving marching orders. That’s not a good model of how people come to know what’s known by science – from the mouth of the scientist to the ear of the citizen. People figure these things out because they are situated in networks of other people who are part of their everyday lives. And those networks ordinarily guide them reliably to what’s known. 

e360: In a study you and colleagues published in the journal Nature Climate Change, you found that as scientific literacy increases, polarization on climate change actually increases as well. Why would that be? 

Kahan: Once you have an issue that has become a signifier of your membership in and loyalty to the group, then making a mistake about that can be really costly to your membership in that group. If I marched around [the Yale] campus with a sign that said, “Climate change is a hoax,” even though I have tenure, my life wouldn’t be as good as it is.

You know, Bob Inglis, the congressman from South Carolina, he was like the Babe Ruth of conservative political ratings. Nobody did better than he did [in ratings from conservative groups] across all the issues that normally determine whether you are a conservative in good standing. And then one day he says, “Well, I’m concerned about climate change and what impact that could have on my constituents and other people in the country.” Soon after that, he is out of office because he is defeated in the primary. Now, imagine that you are a barber in the 4th District of South Carolina [which Inglis represented in Congress]. Do you think it is a good idea when somebody comes in for a shave to hand them a petition that says, “Save the polar bears” or something like this? I mean, you’ll be out of a job as quickly as he was. The impact of making a mistake relative to your group membership is large. The cost of making a mistake on the science is zero. 

So I think that people, because they generally process information in a way that is good for them, are going to predictably form views that connect them to their group.

e360: So, they’re being rational. 

Kahan: That’s a kind of rationality. You don’t have to be a rocket scientist or a climate scientist to do that with respect to climate change because it’s really obvious what position your group has. 

e360: Let’s talk about a fascinating experiment that you carried out. You asked people to assess a study on climate change after reading one of three articles. One article had nothing to do with climate change, another called for strict CO2 regulations, and a third advocated research on geo-engineering, the manipulation of the environment to offset the rise in CO2. You found that the group that read the geo-engineering article was less polarized over the validity of the climate change study. Why would that be so? 

Kahan: We examined whether people, in judging the validity of evidence on climate change, would be more or less open-minded based on whether they had just previously been exposed to information either about geo-engineering or carbon limits. Logically speaking, whether the information on climate change is valid doesn’t depend on whether you can do carbon emissions limits or geo-engineering or anything else. There either is a problem or there isn’t. But psychologically, the hypothesis was that these two kinds of stories would determine the meaning that people attached to the evidence on climate change. The meaning of the carbon limit story was the one that tends to make more individualistic people resist evidence on climate change. It’s kind of like a game-over message. The geo-engineering story, on the other hand, has in it certain kinds of themes that people who have an individualistic world view are moved by and find inspiring – the fact that we use our ingenuity to overcome and deal with limits, including the limits that themselves might be generated by the use of our own ingenuity. So just knowing that geo-engineering was a possibility, the hypothesis was that that would generate a meaning for the subsequent evidence we showed them on climate change that wouldn’t be nearly as threatening. And measuring the outcome here is simple: Are you engaging the information in a more open-minded way? And we found that they were, and because they were, there was less polarization. 

e360: It’s hard to imagine Bill McKibben, for instance, tweaking his message as he campaigns against the Keystone XL pipeline. McKibben, I imagine, is going to continue to call for exactly what he believes in: no pipeline. I’m wondering, as far as climate change goes, maybe these positions have been too entrenched for too long to hope for any reduction in polarization. 

Kahan: I’m not sure about Bill McKibben. I haven’t talked to him, so I don’t know what he thinks. But I do know [climate scientist] James Hansen thinks that you ought to have nuclear power. We did the same experiment where we used nuclear power [instead of geo-engineering] and we got similar effects. 

I think the only thing that is certain not to work would be a style of framing the issues and presenting information that continues to accentuate the perception that the sides on the debate are identified with particular groups. I believe there are ways – in fact, many ways – of presenting the information about climate and science that don’t have that effect. The question is: Which ones are like that, and how could you deliver them? The point is, are there ways to combine science with meanings that would be affirming rather than threatening to people? I think if somebody believes there aren’t any, I think that person just doesn’t have much imagination. 

e360: You do offer some examples at the local level – Florida, for instance – where adaptation to climate change has taken place without running into the cultural identity obstacle. Why wasn’t the individualism/communitarianism dynamic at work in those instances? 

Kahan: The reason there is potential to promote engagement there is that the meanings are entirely different. People in Florida have had a climate problem since they got there. It’s a bad climate. It gets overwhelmed by water and hurricanes. It’s not like this is news to them. I can find materials that were distributed in the 1960s that are not all that much different from what they are using now to try to explain to people why you have to worry

These are decision-makers who are getting information from scientists and trying to make sense of it.”

about saltwater penetration into the aquifers. Every few years you have to do things since sea level rises. They are used to talking about this, and they’re used to talking about it with their neighbors. They may be red and blue when talking about certain national issues, but they’re all just property owners. The insurance guy is there saying one thing, and so is the power company. Now, people are going to squabble because choices always have to be made in politics. But for purposes of this debate, they are all on the same team. You don’t have to come up with clever framing messages. Just use the way that people already talk about these issues. 

e360: Are you saying that in Florida they talk about the threat of climate change without actually using the words “climate” and “change?” 

Kahan: People talk about climate and climate change in Florida, but really what they talk about is: How do we deal with the problem we’ve always dealt with? I don’t know that there is a taboo on mentioning the word “climate.” What they’re talking about is: What do we do here in Florida? 

e360: I understand that you have a project on the ground in Florida right now, in which you are looking at science communication on the issue of climate change. 

Kahan: We’re advising different municipal actors who are part of the Southeast Florida Regional Climate Compact. Those groups are working together from Florida’s four most populous counties to implement a directive that was actually passed by the Republican legislature and signed by the Republican governor in 2011: that everybody should update their comprehensive land-use plan to reflect the most recent information on sea level rise and other kinds of adverse climate impacts. We’ve been talking about how to create a science communication environment in which the members of the public will be receptive to the type of information that travels to them. But, of course, a lot of time what you’re communicating is: How about the estimates from this model about exactly how much sea level is going to rise? And how about that model and what if we made this assumption? 

These are decision-makers in administrative positions who are getting information from scientists and are trying to make sense of it and understand the trade-offs and the costs and benefits. What we try to do is help the members of the compact understand what the best evidence is on the ways to communicate the science. 

Orignially posted on Yale Environment 360.

Image Credit: Polarization photos by Andrew Davidhazy.

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In an interview with the editorial board of Montreal's newspaper, La Presse, Minister Joe Oliver seems to have 'out' himself as a climate change denier.

As La Presse reports, Minister Oliver suggested Canada should push for more aggressive development in the tar sands. The global demand for oil is on the rise while concerns about the climate are beginning to fade.

"I think that people aren't as worried as they were before about global warming of two degrees," he said.

"Scientists have recently told us that our fears (on climate change) are exaggerated," he added, although could not point to which scientist are behind that claim.

Minister Oliver did point to a report by the highly-respected International Energy Agency (IEA), which suggested oil demand will grow by 36 percent. "We have the opportunity to participate in this growth, but we must hurry," he said.

As Postmedia's Mike De Souza reports, Oliver also pointed to a recently revised warming prediction by the UK's Met Office. The Office says temperatures are predicted to rise by 0.43 degrees Celsius by 2017, rather than the previously stated 0.54 degrees.

The revised prediction was "seized upon by by climate sceptics who were already arguing that global warming had 'stopped' since the record breaking year of 1998 and that this new development further undermines both climate science itself as well as any policy response to rising temperatures," reported Leo Hickman from The Guardian.

"Climate scientists have responded saying that to draw such a conclusion is misleading."

Minister Oliver also admitted that he was unfamiliar with the IEA's recent conclusion that the majority of the world's oil reserves must remain in the ground if a 2 degree Celsius increase in temperature above pre-industrial levels is to be avoided. A 2 degree rise in temperature would put the earth's atmosphere beyond the 'tipping point' of runaway global warming.

"No more than one-third of proven reserves of fossil fuels can be consumed prior to 2050 if the world is to achieve the 2 degrees C goal," the report states.

Minister Oliver told La Presse, "I have no idea, I didn't read that conclusion."

The IEA report also emphasized a dwindling demand for unconventional fuel sources, like the tar sands, according to a number of energy scenarios. The high carbon emissions associated with the tar sands are likely to contribute to the fuel's undesirability moving into the low-carbon future. According to the IEA, Canada already has more tar sands projects approved than the world will want.

The IEA says Canada already has more tar sands oil in the works than the world will want, reports the Vancouver Observer's Barry Saxifrage.

Despite Minister Oliver's claims to the contrary, global concern about climate change is having an affect on Canada's high-carbon energy production. The Minister's own office is already concerned about the impact climate change efforts will have on production in the tar sands.

On this point, Minister Oliver seems dangerously out of date. In a separate article he told La Presse the government cannot "analyse the world each time" an energy project is up for environmental assessment and review. The federal government currently refuses to consider tar sands emissions when considering the environmental impact of tar sand pipelines like the Northern Gateway Pipeline or the recently-proposed west to east tar sands line.

The Minister's climate change denial is certainly bad for Canada's credibility as a nation, but it may come to damage the country's economic development too, if basic global environmental concerns are something our leaders willfully choose to ignore.

Minister Oliver's sentiments today are certain to rub the United States, a country committed to reducing its carbon emissions, in the wrong way.

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On Monday night one of the world's most famous climate scientists took the stage at the University of Victoria in B.C. as part of the university's Lansdowne Public Lecture series.

Michael Mann, popularly known for his research involving the 'hockey stick' graph – undoubtedly the most iconic and controversial image of global warming science – presented on his book The Hockey Stick and the Climate Wars: Dispatches from the Front Lines.

Hounded, hunted and harassed, Mann has suffered much of the public backlash against climate science over the last decade, being accused of everything from conspiracy and fraud to scientific dishonesty.

He has been at the centre of several of the last decade's most high-profile climate science smear campaigns including the Cuccinelli subpoena circus in 2010, the debunked 'Climategate' charade, and a failed climate scientist witch-hunt led by Congressman Joe Barton. 

Despite all the controversy, Mann is resolute in his efforts to address climate change in a meaningful way which involves making some difficult social decisions.

There's "no magic bullet" solution, he says and so "even controversial proposals need to be weighed."

But solutions are what come once we've recognized the problem. For Mann, there is still some work to be done on the ground in that regard, especially when it comes to our over-reliance on fossil fuels.

"We can't have that discussion until we accept that the challenge is real, the problem is real, and we shift away from the burning of fossil fuels."

"We are obviously going to need to incentivise that shift away from fossil fuels, both in American and in Canada," Mann says, mentioning carbon tax and cap and trade legislation as popular considerations on this front.

Although, Mann will tell you, he doesn't necessarily see himself as one to advocate for certain policies. Scientists, he feels, should for the most part stick to science. Although that is easier said than done when the science is being mishandled.

Hazarding the risks of appearing politics, Mann says that sometimes scientists have to weigh in when facts are mishandled and information misrepresented. As a climate scientist Mann, at times, has been given no choice but to speak up. 

"I'd like to think [climate scientists] are not being political for standing up for science. Sometimes I'm accused of being an advocate because I'm fighting back against the disinformation effort, against the attacks on climate science. And my argument would be that, if by advocate you mean an advocate for the notion that our public discourse on this issue should be informed by an honest assessment of the science, then I'm happy to wear the mantle of advocate."

He adds, "I stop short of trying to proscribe policy. I leave that to be worked out in good faith by politicians as long as they're playing by fair ground rules, as long at they're accepting reality of the threat and risks that [the science] exposes."

Scientists have to decide for themselves when it's appropriate to speak out either for or against specific policy decisions.

James Hansen, says Mann, has taken a very strong position on a carbon tax. Some, he says, "are just more comfortable weighing in on these kinds of matters than others."

But in "all matters of policy there is a role for government regulation, for government policy to incentivise. [Incentives] would take us in the direction we need to go."

Looking forward, we've got a lot of options, according to Mann. To avoid replicating the mistakes of the past, we will need to come to terms with our pollution and the way our current business-as-usual model allows us to externalize certain – especially environmental – costs.

"When it comes to carbon emissions, there is a hidden cost: we're doing damage to the planet. But that cost is not internalized. We're not paying for that damage – through a carbon tax or cap and trade legislation."

So when we're talking about accounting for our pollution and emissions, "we're simply talking about levelling the playing field when it comes to alternative energies."

But not all discussions about if or how to move forward can take place in the realm of science, politics or policy, says Mann. There is a moral element not to be forgotten.

"To me more than anything else it's a debate about what kind of world we leave for our children."

Mann moved to a photograph in his presentation, one of his daughter smiling, watching a polar bear swim overhead along a tall aquarium window.

"I hate to think we're going to leave a world for our children where they could come back to a zoo like this decades from now and point to these animals that used to live in the Arctic before we essentially melted their environment," he said.

"And that, of course, is emblematic of a much larger and very serious set of detrimental changes that we are going to be making to this planet if we continue developing these concentrations of greenhouse gasses in the atmosphere if we don't shift away from our current reliance on fossil fuels."

"So to me," Mann added, "it's really a matter of what kind of world we are going to leave behind for our children and our grandchildren. It's important that we make the right choices so that we don't leave behind for them a degraded planet."

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