Quotes of the Day

It's a question whispered by climate scientists and pondered by environmental activists: why don't they believe us? When the U.N. Intergovernmental Panel on Climate Change (IPCC) released its fourth assessment on climate science in 2007the one that called evidence of warming temperatures "unequivocal" — it seemed as if the scientific debate over global warming was essentially over. There would be disputes over how best to lower carbon emissions, how much money should be devoted to adaptation and just how severe future warming might be. But surely, we were done arguing about whether man-made carbon emissions were making the planet hotter.

Apparently we're not. The past few years have seen a marked decline in the percentage of Americans who believe what scientists say about climate, with belief among conservatives falling especially fast. It's true that the science community has hit some bumps — the IPCC was revealed to have made a few dumb errors in its recent assessment, and the "Climategate" hacked emails showed scientists behaving badly. But nothing changed the essential truth that more man-made CO2 means more warming; in fact, the basic scientific case has only gotten stronger. Yet still, much of the American public remains unconvinced — and importantly, last November that public returned control of the House of Representatives to a Republican party that is absolutely hostile to the basic truths of climate science.

That much was on display Tuesday, when the House Energy and Commerce Committee's subcommittee on energy and power (it's not quite as redundant as it sounds) held a hearing on a proposed bill that would strip the Environmental Protection Agency of its power to regulate greenhouse gases. Scientists from both sides of the climate question testified, and representatives from both sides of the aisle jostled over the veracity of mainstream science.

Representative Jay Inslee, a Democrat from Washington and one of the fiercest advocates for action on climate change, spoke for environmentalists across the country when he wondered why Republicans suffered "an allergy to science and scientists," as he put it. "If Copernicus, Galileo, Newton and Einstein were testifying today, the Republicans would not accept their views until all the Arctic ice has melted and hell has frozen over, whichever comes first," Inslee said.

As it turns out, Inslee might well be right, because facts and authority alone may not shift people's opinions on climate science or many other topics. That was the conclusion I took from the Climate, Mind and Behavior conference, a meeting of environmentalists, neuroscientists, psychologists and sociologists that I attended last week at the Garrison Institute in New York's Hudson Valley. We like to think of ourselves as rational creatures who select from the choices presented to us for maximum individual utility — indeed, that's the essential principle behind most modern economics. But when you do assume rationality, the politics of climate change get confusing. Why would so many supposedly rational human beings choose to ignore overwhelming scientific authority?

Maybe because we're not actually so rational after all, as research is increasingly showing. Emotions and values — not always fully conscious — play an enormous role in how we process information and make choices. We are beset by cognitive biases that throw what would be sound decision-making off-balance. Take loss aversion: psychologists have found that human beings tend to be more concerned about avoiding losses than achieving gains, holding onto what they have even when this is not in their best interests. That has a simple parallel to climate politics: environmentalists argue that the shift to a low-carbon economy will create abundant new green jobs, but for many people, that prospect of future gain — even if it comes with a safer planet — may not be worth the risk of losing the jobs and economy they have.

Group identification also plays a major role in how we make decisions — and that's another way facts can get filtered. Declining belief in climate science has been, for the most part in America, a conservative phenomenon. On the surface, that's curious: you could expect Republicans to be skeptical of economic solutions to climate change like a carbon tax, since higher taxes tend to be a Democratic policy, but scientific information ought to be non-partisan. Politicians never debate the physics of space travel after all, even if they argue fiercely over the costs and priorities associated with it. That, however, is the power of group thinking; for most conservative Americans, the very idea of climate science has been poisoned by ideologues who seek to advance their economic arguments by denying scientific fact. No additional data — new findings about CO2 feedback loops or better modeling of ice sheet loss — is likely to change their mind.

What's the answer for environmentalists? Change the message and frame the issue in a way that doesn't trigger unconscious opposition among so many Americans. That can be a simple as using the right labels: a recent study by researchers at the University of Michigan found that Republicans are less skeptical of "climate change" than "global warming," possibly because climate change sounds less specific. Possibly too because so broad a term includes the severe snowfalls of the past winter that can be a paradoxical result of a generally warmer world. Greens should also pin their message on subjects that are less controversial, like public health or national security. Instead of issuing dire warnings about an apocalyptic future — which seems to make many Americans stop listening — better to talk about the present generation's responsibility to the future, to bequeath their children and grandchildren a safer and healthy planet.

The bright side of all this irrationality is that it means human beings can act in ways that sometimes go against their immediate utility, sacrificing their own interests for the benefit of the group. (Indeed, every day over the past month and a half in the cities of the Middle East we have seen human beings irrationally risking their lives for their values.) Our brains develop socially, not just selfishly, which means sustainable behavior — and salvation for the planet — may not be as difficult as it sometimes seem. We can motivate people to help stop climate change — it may just not be climate science that convinces them to act.

• Bryan Walsh
• It's a question whispered by climate scientists and pondered by environmental activists: why don't they believe us?