Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.


Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Donate

Twitter Facebook YouTube Pinterest

RSS Posts RSS Comments Email Subscribe

Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...

Keep me logged in
New? Register here
Forgot your password?

Latest Posts


Climate Hustle

Why the 97% climate consensus is important

Posted on 2 October 2017 by dana1981, John Cook

John Cook is a research assistant professor at the Center for Climate Change Communication at George Mason University, researching cognitive science.

Sander van der Linden is an Assistant Professor in Social Psychology, Director of the Cambridge Social Decision-Making Lab and a Fellow of Churchill College.

Anthony Leiserowitz is a Research Scientist and Director of the Yale Project on Climate Change at the School of Forestry and Environmental Studies at Yale University.

Edward Maibach is a University Professor and Director of Mason’s Center for Climate Change Communication.

Unfortunately, humans don’t have infinite brain capacity, so no one can become an expert on every subject. But people have found ways to overcome our individual limitations through social intelligence, for example by developing and paying special attention to the consensus of experts. Modern societies have developed entire institutions to distill and communicate expert consensus, ranging from national academies of science to the Intergovernmental Panel on Climate Change. Assessments of scientific consensus help us tap the collective wisdom of a crowd of experts. In short, people value expert consensus as a guide to help them navigate an increasingly complex and risk-filled world.

More generally, consensus is an important process in society. Human cooperation, from small groups to entire nations, requires some degree of consensus, for example on shared goals and the best means to achieve those goals. Indeed, some biologists have argued that “human societies are unable to function without consensus.” Neurological evidence even suggests that when people learn that they are in agreement with experts, reward signals are produced in the brain. Importantly, establishing consensus in one domain (e.g. climate science) can serve as a stepping stone to establishing consensus in other domains (e.g. need for climate policy).

The value of consensus is well understood by the opponents of climate action, like the fossil fuel industry. In the early 1990s, despite the fact that an international scientific consensus was already forming, the fossil fuel industry invested in misinformation campaigns to confuse the public about the level of scientific agreement that human-caused global warming is happening. As has been well-documented, fossil fuel companies learned this strategy from the tobacco industry, which invested enormous sums in marketing and public relations campaigns to sow doubt in the public mind about the causal link between smoking and lung cancer.

However, some academics have recently argued that communicators and educators should not inform the public about the strong scientific consensus on climate change. UK sociologist Warren Pearce and his colleagues recently published a commentary (and corresponding Guardian op-ed) arguing that communicating the scientific consensus is actually counter-productive. John Cook published a reply, which we summarize here.

Playing into misinformers’ hands

By the late 1990s, political strategists recognized the importance of perceived scientific consensus. Market researcher Frank Luntz advised Republicans and then-president George W. Bush to cast doubt on expert agreement in order to reduce public support for climate policy. To stall climate policy, he argued, the Bush Administration should seek to convince the public that scientists were still arguing whether climate change is real or human-caused.

Evidence Squared podcast on why denialists attack consensus.

Luntz was ahead of his time. It was over a decade before social scientists began studying this phenomenon and converged on the same result. A 2011 studyfound that support for climate policy was linked to perceptions about scientific agreement on climate change. This finding has since been independently replicated by other research, as well as randomized experiments conducted in Australia and the United States. Still other research confirmed these results using John Oliver’s viral TV segment illustrating the issue of “false balance” to the public.

HBO’s Last Week Tonight with John Oliver: A Statistically Representative Climate Change Debate.

Conversely, telling people that experts disagree was found to decrease their support for environmental policy and other actions, such as vaccinations.

Opponents of climate action may reject scientific evidence supporting the reality of human-caused climate change, but they have diligently applied the social scientific evidence indicating how to reduce public support for climate action. An analysis of conservative op-eds found their most common claim was “there is no consensus.” An analysis of a six-month period in 2016 found that the most-shared climate article on social media was about an online petition designed to cast doubt on the scientific consensus. It’s why the Trump administration wants to televise a Red Team/Blue Team climate debate.

To push back against the decades-long disinformation campaign, numerous scientists have made efforts to quantify and communicate the scientific consensus. Meanwhile, disinformers have doubled down on their efforts to confuse the public about the consensus. The commentary by Pearce and company plays into their hands by arguing the climate community should surrender this argument to the misinformers.

A misperception of reality

In the Guardian, Pearce argued:

the public have already heard enough about the scientific evidence to make up their mind, without being fed increasingly esoteric information about levels of scientific agreement … valuable media and political attention has been expended on boosting the 97% meme, crowding out deeper conversations about policy framing

However, in the United States, only 70% of Americans understand that global warming is happening, and only 58% understand it is human-caused. Further,only 13% of Americans realize the expert consensus on human-caused global warming exceeds 90%

consensus gapPerceived expert climate consensus across the political spectrum from a nationally representative sample of 200 Americans. Even liberals significantly underestimate the expert consensus on human-caused global warming. Illustration: John Cook

And multiple empirical studies, conducted in different countries, have found that informing people of the scientific consensus has a small but significant influence on their own subsequent judgements about the reality of human-caused global warming. While discussion about climate policy is urgently needed, establishing and communicating the scientific consensus about human-caused climate change is not a competitor to policy discussion; it is a complement. 

No one argues that the scientific consensus is the one and only message that needs to be communicated - public responses to climate change are often as complex as society itself. But informing the public about the scientific consensus that the problem actually exists can support the discussion on how to best solve the problem. The argument that we have to choose between debunking the climate policy opponent’s disinformation about the scientific consensus or engage in meaningful policy dialogue is a false choice.

Disinformation about the scientific consensus that human-caused climate change is happening has been used to delay serious conversations about climate policy in the United States and a few other countries. Moreover, the argument that communicators should not talk about a scientific consensus when one exists is deeply troubling. In the history of science, it is relatively rare that such strong agreement emerges about basic scientific facts. When it comes to issues such as the future of our planet, recommending that we withhold this information from the public is unethical.

Consensus messaging isn’t responsible for climate policy failures

American policymakers have struggled to implement national climate policies, but not for lack of policy discussion “crowded out” by consensus messaging. 

Click here to read the rest

0 0

Bookmark and Share Printable Version  |  Link to this page


Comments 1 to 8:

  1. Pearce's line of argumentation is not being completely represented here. He is not trivializing or belittling the important contribution that consensus awareness can make, nor stating outright that there is nothing left to accomplish on this score, but stating that public discussion about the exact method and numbers to establish consensus accuracy can divert attention into politicized discourse that detracts from a much more urgent question, viz., how to get more support for policy measures. Better consensus awareness does not necessarily lead to more preparedness to support the needed policy measures (e.g., carbon taxes), and how to fuel such motivation is a trickier and more urgent question. The 97 number can become a fetish, depending on precisely which question is being analyzed. The fact that there are no creditable attempts at explaining comprehensively the many lines of evidence speaks to me like 100%.

    In terms of policy measures, the uncertainties with regard to outcomes is obviously much greater than the basic science about the problems we face. Overcoming that uncertainty in order to still get something done is a challenge of a different order, and one not addressable by science alone: it is more akin to persuading someone not to light up that next cigarette, knowing that one cigarette less is not exactly a matter of life or death.

    0 0
  2. Good article thanks. Consensus is vitally importantant, and we need to know about the consensus. Clearly over 90% of scientists agree we are altering the climate from various studies, and this alone is obviously important, and at least in that it should be getting our strong attention or we are idiots.

    Nothing good comes from hiding information, at least not from adults.

    This is partly why consensus is important as follows. Consensus at least gives us an indication of where the general thinking is going, and what is most likely to be the correct answer. The general public often struggle with scientific detail and obviously dont have the time to read the detailed science. As a result the first question many people ask is what do the experts think? The general public do this, politicians do this. As part of this process its important to be sure we get the thoughts of a wide range of scientists, and particularly the consensus view. We don't want to be listening to just one dissenting sceptical voice, not realising that voice may be in a minority. We need context, and dont want to get fooled into thinking opinion is divided if it isnt.

    If the majority of scientists agree on something, that is cause to at the very least pay attention, while a 50 / 50 split would suggest more work is needed. But it also depends on how serious the threat is, because a very serious threat (like an asteroid heading our way) might suggest even a 50 / 50 split of opinion on the matter should still suggest precautionary action is desirable. 

    I disagree with the view by Pearce in the Guardian that publicising the consensus view is counter productive. Only had time for a quick scan through the article, but straight away he bases his view that we don't need to publicise the consensus because reasonably good numbers already think climate is changing, its a problem, and we should do renewable energy . Those are correct figures, but omit the fact that only low numbers in America think humans are causing climate change. This is very significant, because this line of thinking will colour the totality of our response to climate change. And the consensus goes right into causation. 

    However Pearce makes a good point that arguing too much about the exact level of consensus is a waste of time. Ideally we want more awareness of the consensus in the general media, but to avoid getting bogged down to debating exact numbers too much, etc etc. 

    There are indeed a whole lot of other things to focus on as well as others point out. I agree with JW Rebel the challenge is around dealing with responses and uncertaity of outcomes etc. One thing that may help is much more specific information on how much transitions to renewable energy will cost the averagre person per year in dollar terms (and the data suggests not actually very much). Right now the numbers on this are not front and centre of debate, and are quoted in terms of gdp, which half the population don't even understand or find hard to visualise. Lack of clear, simple information creates uncertainty and fear.

    0 0
  3. I read that as many as 10 times more people watch the network evening news than cable evening news. Particularly the age 50+ demographic, including myself. Cable has more viewing overall because it's there 24/7. FOX gets the biggest share but the others have a fair share to. 

    Point is, can't there be a way to get some of what we see in these postings and others more regularly out to these audiences, obviously geared to a generally uninformed public. The "it's natural", "climates always changing", "humans couldn't possibly affect nature", etc., etc. needs to be countered, especially for this group of more senior folks. I think it's essential to address the disturbingly low recognition or acceptance of the conscensus. How about the red/blue debate on prime time TV, or is that bridge too far?

    0 0
  4. Debates tend to be won by the best debater not the best argument and even if not, you "win" if you make points that appeal to your target audience and can throw doubt on your opponent even if with blatent lies. The problematic bit of our current world is that people choose media sources which give them a reality tailored to their prejudices and a symbiotic relationship sets in which polarizes views. Left and right are equally at fault. Internet makes it worse. I wish I knew the answer. The problem is that reality is not actually a consumer choice and treating it as such bites us.

    And I think this comic makes courageously true statements about the problem. Well worth a read.

    0 0
  5. Scaddenp @4

    Agreed. Debates are often won on inflammatory slogans, appeals to emotion, generalisations, cherrypicking,and plain falsehoods, sadly to say, as opposed to facts and reasoned argument. This is particularly the case with talk back radio. Another debating tactic is sophistry.

    The frustrating thing is real scientists cannot afford to engage in inflammatory rhetoric or anything that could be interpreted as dishonest, or their jobs could be under threat. And shouldnt anyway of course goes without saying.

    In contrast you get certain sceptics who get away with the most incredible falsehoods and inflammatory rhetoric, because they are assured of a job or funding from think tanks lurking in the background. Not naming names or the moderator will have a fit.

    Its a most unfair pack of cards, and I dont know the answer, although I think the general public are mostly aware of this, and do make some allowances. Anyway scientists should stick to sound fact based debate I think or it will be chaos. The truth wins in the end.

    People do seek out places that confirm their views and yes we are all vulnerable. The internet has amplified this, however I make an effort to look at all sides of debates and find it interesting to explore this.

    The internet bubble phenomenon is also now generating fake news, and a real distortion of reality, and the answer is indeed elusive, but I can see most people getting heartily sick of this confusion, nonsense, conspiracy twaddle and and the lack of a solid base of facts, and things may swing back to the centre like the pendulum of a clock. Dont understimate the basic sanity of the silent majority. It can't happen soon enough.

    0 0
  6. Scaddenp @4

    Absolutely, I agree.

    One approach I would like to see taken "full throttle" is to use one of the skeptics own tactics against them, and yes skeptical science does an excellent job of that by showing what is being said and pointing out what is wrong and showing why. However, my suggested approach is to address the sources specifically. Who they are, a list of their deliberate falsehoods and how easy it is to show that such claims are false. And I think those falsehoods in particular should be the ones that accuse scientists and climate organizations of manipulating data. True, there is a lot of confirmation bias performed by the skeptics, but in all honesty, I think the ones that cause the most public doubt are the ones who "deliberately" accuse scientists and organizations (NASA, NOAA, HadCRUT, etc., of misdeeds, when it is they who are the ones engaged in misdeeds.

    1 0
  7. "Pluralistic Ignorance" is a helpful concept here. The great contribution by Frank Luntz to Denialism's staying power was straight from Gen'l Nathan Bedford Forest's alleged dictum: "Get there fustes' with the mostes'." The part about the credibility of scientists and their concensus is important but fairly obvious.

    Thus, propagandize that there is no concensus first, then "everybody" will believe that "everybody else" believes it. "The rest is commentary."

    Separately, I love that comic strip linked in #4.

    0 0
  8. As this is your first post, Skeptical Science respectfully reminds you to please follow our comments policy. Thank You!

    Has anyone suggested the obvious question for those who are claiming to have the intelligence to evaluate the climate science data (and are mis-leading the public)?  

    For example -

    "You are claiming to have some ability to evaluate the information on climate science.  You are also claiming that the evidence does not support that humans are contributing to accelerated global warming.  My question is this - How, exactly, would you design a study to prove (or disprove) your claim?  What kind of data would you gather, measurements would you make? information would you need to prove/disprove this question?"

    It seems to me that those who are creating doubt have been putting creditable scientists on the defensive.  We know that they can make broad claims that gloss over the consensus.  We also know that most people won't even bother to gather more information - for legitimate reasons.  It is daunting.  I am wondering if this question was asked in a format where they could not evade it (say on a televised National Debate) if their strategy would begin to crumble?

    0 0

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.

The Consensus Project Website


(free to republish)

Smartphone Apps


© Copyright 2017 John Cook
Home | Links | Translations | About Us | Contact Us