HOW do you get your point across over an issue as contentious as climate change? As a hearing in the US Congress last week showed, the evidence alone is not enough.
At issue was the authority of the Environmental Protection Agency to regulate greenhouse gas emissions. Republicans in the House and Senate are backing bills that would strip the EPA of that right, which is based on findings that rising carbon dioxide levels pose a threat to health and the environment.
At the hearing, House Democrats hoped to counter these moves by calling a cast of climatologists to explain the weight of scientific evidence for climate change. A meeting of minds it was not. The effort seemed only to harden Republican scepticism.
For Dan Kahan of the Cultural Cognition Project at Yale University, the result was predictable. He has previously shown that simply explaining the science behind contentious issues drives the two sides further apart. But Kahan's work also suggests how warring parties can move towards consensus.
Kahan grades people on two scales of cultural belief: individualists versus communitarians, based on the different importance people attach to the public good when balanced against individual rights; and hierarchists versus egalitarians, based on their views on the stratification of society. Republicans are more likely to be hierarchical-individualist, while Democrats are more often egalitarian-communitarian.
People's views on contentious scientific issues tend to reflect their position on these scales. For example, egalitarian-communitarians tend to accept the evidence that climate change is a threat, while hierarchical-individualists reject it.
Yet people's views do change if the right person is offering the evidence. Kahan investigated attitudes for and against giving the human papillomavirus (HPV) vaccine to schoolgirls to prevent cervical cancer - another divisive issue. After he presented people with both sides of the argument, he found that 70 per cent of egalitarian-communitarians thought it was safe, compared with 56 per cent of hierarchical-individualists.
When the "pro" argument was presented as coming from an expert painted as being in the egalitarian-communitarian camp, and the "anti" view came from a hierarchical-individualist, the split widened to 71 versus 47 per cent. But strikingly, swapping the experts around caused a big shift: 61 per cent of hierarchical-individualists then rated the vaccine as safe, compared to 58 per cent of egalitarian-communitarians. In short, evidence from someone you identify with sways your view.
In practice, it is hard to find experts who will give "unexpected" testimony. But when the evidence was presented by experts with a variety of backgrounds, views were not so starkly polarised, with 65 per cent of egalitarian-communitarians and 54 per cent of hierarchical-individualists agreeing that the vaccine is safe.
So who might be best placed to change Republicans' minds over the EPA bill? Maybe specialists from the insurance industry, which is factoring climate change into its calculations, the military, or religious environmentalists.
Kahan accepts that it would be naive to think that climate sceptics will suddenly abandon their position. But he says: "We want to create an environment in which people, regardless of their values, are giving considered attention to the information."
- Subscribe to New Scientist and you'll get:
- New Scientist magazine delivered to your door
- Unlimited access to all New Scientist online content -
a benefit only available to subscribers - Great savings from the normal price
- Subscribe now!
If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.
Have your say
Only subscribers may leave comments on this article. Please log in.
Only personal subscribers may leave comments on this article
Protect Us From The Environmental Protection Agency
Thu Mar 17 12:32:08 GMT 2011 by Eric Kvaalen
While I recognize the value of persuading people to act in the best way, and the importance of lowering our use of fossil fuels, I'm not convinced that using the EPA is the right way to tackle this problem.
One thing that really bugs Republicans and the like is excessive regulation!
I think a carbon tax is a much better solution. You tax the fossil fuels at source and let market forces take care of the rest. The revenue from the tax would be great for the government. The tax would decrease the amount of money going out to the oil producing countries.
But I don't have much success convincing climate-change skeptics of the need for a tax!
Protect Us From The Environmental Protection Agency
Fri Mar 18 18:25:48 GMT 2011 by opit
http://opitslinkfest.blogspot.com/
The GOP are caught up in 'Force Projection'....aaah that's unfair. Both parties are because both fund it. Wasn't that easy ?
Petroleum is a strategic material. WW II was instigated by cutting Japan's access to petroleum ( look it up if you don't believe me )
There is no current technology which can supply energy at the rates it is liberated from underground storage. There's an excellent overview of why this is at the Youtube/homeproject channel So the military industrial complex is maximizing their advantage. Part of this is knowing that wind technology is subject to catastrophic failure from gusts. Another was harassing liscencees of atomic power generation technologies. See The NPT Trap.
So it's not just oil, but energy, water and more that are in play. A Search on Rumsfeld/Monsanto will bring home food warfare...destruction of food supply.
In this context a distraction is needed - multipurpose as usual. A global tax on the use of fire - suitably perverted to tax and harass the poor. And carbon credits were the subject of fraud lawsuits years ago.
So. To say I'm 'skeptical' about honest foretelling the future without so much as a crystal ball from the people who brought me television advertising and Talking Heads is no understatement.
But hey, it's all Rush Limbaugh, right ?
Never heard the man. Can't and wouldn't bother trying.
What's this doing in a 'science' forum ? It's politics and religion.
Use Of Correct Terms
Sat Mar 19 01:27:30 GMT 2011 by Ian W
So New Scientist has descended to talking of 'climate change' rather than what it means - 'Anthropogenic Climate Change'.
It may have escaped your notice but world climate continually alters. The Maya civilization appears to have failed due to drought. The Egyptian civilization grew because of migration from the Sahara as it turned from forest into desert. Vikings famed on Greenland until overwhelmed by new glaciation.
What is being claimed is that the latest small rise in 'average global temperatures' is due to burning fossil fuels. Not previous changes - just this one.
The fact that CO2 has been higher in previous interglacials without the catastrophic events claimed - is glossed over. If it happens now, we are told the Earth will pass a tipping point from which it will not recover. And your evidence is?
You are probably aware that for most plants to survive there MUST be at least 160ppm CO2 in the atmosphere. If the measurements of pre-industrial CO2 are to be believed (and as they are from ice cores that may not be believable) then in pre-industrial times the world was dangerously close to loss of plant life. Which I am sure you are aware would mean loss of ALL life- total extinction due to the LOW levels of CO2. Yet you presumably wish to return to that level?
Despite Kyoto - the level of CO2 in the atmosphere has continued to grow. Yet the 'global temperatures' seem to have flattened and are effectively (within statistical significance) at the same level they were 20 years ago.
So yes - you will have to work extremely hard to convince sceptics that civilsation should regress to occasional power and rolling blackouts as you have as yet unpresented (or lost by Phil Jones) evidence that there is a tipping point for climate and then all is lost as the Earth becomes another Mars.
Use Of Correct Terms
Sat Mar 19 03:40:51 GMT 2011 by TwoZeroOZ
And out comes the propaganda.
Use Of Correct Terms
Sat Mar 19 20:09:22 GMT 2011 by Karl
Yes, "Ian W" and "albert frankenstein" don't sound like complete fools. More likely they are consultants paid by the fossil fuel industry.
Use Of Correct Terms
Mon Mar 21 02:40:45 GMT 2011 by Liza
Nah, they do sound like complete fools. Fools who have learned to talk pretty. Which is the worst kind.
Abandon All Reason
Sat Mar 19 11:15:36 GMT 2011 by albert frankenstein
Having spent quite some time researching climate models as part of my higher degree, (MSc) in CS, I have come to the conclusion that there is no falsifiable hypothesis in any of them and the assumptions are programmed so there can only be one outcome.
For example, the actual response to doubling CO2 without feedbacks is around 0.2 K. The way the models arrive at the higher sensitivities is to place positive feedbacks that amplify the effect of CO2. However, there is no evidence of this feedback at all. I started out believing these models were, though imperfect, a reasonable attempt at prediction, I realised that they are nothing but junk science. Predicting systems with free attractors is really just junk science. I was shocked.
This has caused me to wonder if there is any real basis to the AGW hypothesis as all is based on this and a very unsound surface temperature data set, which I found was privately ridiculed by statisticians world wide.
I thought the whole point of science was to produce falsifiable hypothesis. The more I learn about the science behind the hypothesis the more I find myself thinking my support of AGW is in fact based on nothing more than wishful thinking.
So here is one scientist who was presented with all the evidence, took an unbiased view of the data ant methodologies and actually changed my position from supporting to rejecting the AGW hypothesis.
The elephant in the room is that when people are presented with the facts, they in no way validate or support what has now become the most unsound science in the history of the modern world and I started out at a firm supporter. Congress and Americans may well be smarter than you may think.
Abandon All Reason
Sun Mar 20 06:06:53 GMT 2011 by Eric Kvaalen
I think there's too much emphasis nowadays on "falsifiability" and "evidence", as though that is science. Science means knowledge, and we should use whatever means we have to obtain it (within limits!). In the case of climate modeling, our goal is too estimate what will happen, even if we can't prove it. So it's not a realm in which evidence is what we need. In other words, if you're doing a complicated calculation of a physical system in which you know the physical laws, the problem is how to do the calculation, not whether there is evidence for the results.
I agree that the global warming we have seen so far is small and it's hard to be sure that it is caused by man.
I'm not sure what you mean by a free attractor. But we all know that predicting the exact behavior of a chaotic attractor is impossible. The point is, we're not interested in the exact behavior -- we're interested in the statistics. So I don't see why you were shocked.
I also don't see why you say your support of AGW is (or was) based on wishful thinking. Why would anyone wish for global warming? People may want a warmer climate where they live, but who would want the sort of chaos that would happen in many parts of the world, or the hardship of giving up our beloved fossil fuels?
All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.
If you are having a technical problem posting a comment, please contact technical support.