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 Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube 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...

New? Register here
Forgot your password?

Latest Posts


Palmer United Party needs to go back to school on carbon facts

Posted on 28 April 2014 by John Cook

When you ask Australians what proportion of climate scientists agree on the reality of human-caused global warming, the average answer is around 58%, despite evidence that the true size of the consensus is 97%.

Australians still think there is a roughly 50/50 debate among climate scientists. This is a huge “consensus gap” between public perception and reality.

A one-person embodiment of this statistic is the Palmer United Party (PUP) Tasmanian Senator-elect Jacqui Lambie. She had this to say about the scientific consensus on ABC’s Q&A:

TONY JONES: If you were to speak to a group of scientists and they were to convince you that climate change is a problem, that it’s caused by global warming and that global warming’s caused by emissions, would you think differently about it?

LAMBIE: Well of course I would, but right now I have half the scientists on this side and the other half on this side so, you know…

Crucial votes

Lambie’s views on climate change are based on a fundamental misconception about the scientific consensus on climate change. This wouldn’t matter so much, were it not for two things.

First, Lambie is one of three PUP Senators-elect who, in a bloc with Ricky Muir of the Motoring Enthusiasts Party, potentially represent four of the six votes the government needs to repeal the current carbon policy after the new Senate comes into effect in July.

Second, Lambie’s party leader Clive Palmer is beset with his own confusion about the carbon cycle, recently telling ABC’s Lateline:

If 97% (of greenhouse gas) comes from nature and 3% comes from man and we say we’ve got to reduce it by 1%, we shouldn’t just look at the 3%, the minority section coming from human enterprise; we need to look at the whole concept. If 1 or 2% comes down from nature, surely that’s a good thing and that brings us back into a balance. It’s the total carbon balance you have to look at. But we’re just focusing on this 3%.

Unpicking these misconceptions (which I will do shortly) does not mean advocating one carbon policy over another. But given PUP’s potentially decisive influence, we should at least expect the party’s elected politicians to understand the basic facts so that they might make an informed decision.

Crunching the numbers

So, back to the consensus. If you remember only one number about climate change, this is it. Ninety-seven. This is the percentage of climate scientists who agree that humans are causing global warming.

Several peer-reviewed studies have found overwhelming agreement about this. A 2009 survey of Earth scientists found that among climate scientists actively publishing climate research, 97% agreed that humans were significantly raising global temperature. A 2011 analysis of scientists' public statements about climate change found that among those who had published peer-reviewed climate research, 97% accepted human-induced warming.

I led a team that examined 21 years of published research on global warming. Among the papers that stated a position on human-caused global warming in their abstract, 97.1% endorsed the consensus. We also invited the authors of the papers to rate their own research. Among the papers self-rated as stating a position on human-caused global warming, 97.2% endorsed the consensus.

97% consensus was found in Doran & Zimmermann 2009, Anderegg et al 2011 and Cook et al 2013.

Normally, getting scientists to agree with such near-unanimity is like herding cats. At one climate conference, I watched scientists vigorously argue for an hour about where to go for a beer. What does it take to achieve 97% agreement?

It takes evidence. Not just a paper or two. It takes many independent lines of evidence, all pointing to a single consistent conclusion. Human fingerprints are being observed all over our climate. Tell-tale patterns have been measured in the annual cycle, the daily cycle, the structure of the atmosphere and in outgoing infrared radiation. These all point to rising greenhouse gases as the cause of global warming. These human fingerprints also rule out other natural suspects like the sun or volcanoes.

While I find these human fingerprints fascinating and write about them frequently, the average layperson defers to the opinions of experts on climate change. Fair enough. I don’t browse through engineering blogs every time I cross a bridge to reassure myself that the experts did their sums right.

But when the average Australian thinks the consensus is not 97%, but just 58%, there is clearly a public misconception about what the scientists really think.

Why does this misconception matter? When people think climate scientists don’t agree that humans are causing global warming, they don’t support policies to act on climate change. It is a roadblock preventing meaningful climate action. And when an elected politician like Lambie adopts this way of thinking, the effect is even more powerful because she is elected to represent a large swathe of the public.

In the balance

So can we rely on her party leader to set her straight? I wouldn’t hold out much hope, given his recent comments about the contributions of nature versus industry to the climate problem.

Our planet is in balance. Every spring, nature sucks up hundreds of billions of tonnes of carbon dioxide as plants grow. In autumn, the plants decompose and release the carbon dioxide back into the air. This is the natural balance of the carbon cycle. It’s a circle of life kind of thing.

Humans have upset the balance. By emitting billions of tonnes of carbon dioxide into the atmosphere, we’ve raised atmospheric carbon dioxide to levels not seen in millions of years.

Atmospheric carbon dioxide from Antarctic ice core records – Taylor Dome (green) and Law Dome (red), and from instrumental measurements at Mauna Loa (black).

In claiming that we should reduce emissions from nature as well as industry, Palmer’s mistake (ironically enough) is to ignore the total carbon balance. He has forgotten to consider the fact that every year, nature absorbs everything it emits. The natural world mops up its own emissions. Industry doesn’t, which is why greenhouse gas levels are climbing overall.

The carbon cycle (numbers are billion tonnes of carbon dioxide) taken from the IPCC 4th Assessment Report.

Basic facts

So we have a Senator-elect mistaking a near-universal consensus for a 50/50 debate, while her party leader thinks nature is mostly responsible for rising greenhouse gas levels when it isn’t.

These are pretty basic facts about climate science. Getting them wrong doesn’t inspire much confidence that they will come to grips with the more complex policy issue of what to do about the problem.

The Conversation

John Cook is creator of

This article was originally published on The Conversation. Read the original article.

0 0

Printable Version  |  Link to this page


Comments 1 to 20:

  1. Upton Sinclair ("It is difficult to get a man to understand something, when his salary depends on his not understanding it") may apply here.  "What's that you say, its 97% and not 50%?  Hey Clive, this fellow here says its 47%!!"

    0 0
  2. John,

    "the average Australian thinks the consensus is not 97%, but just 58%"

    First a question, on the page with the bar graph, you write that the data is based on "a survey of a US representative sample." What is that? To me, an American, "US" means people from my country. So, what is "a US representative sample"?

    Next, I'm not sure referring to "the average Australian" as you do is particularly useful. I'm always happy to see breakdowns of just what various groups of Australians (and Americans and Brits and Canadians, etc.) think about issues, but it seems to me that "the average Australian" or "the average American" or "the average any other citizen" is a very nebulous person indeed and the 58% figure you refer to in actuality characterizes the situation for all Australians. For example, this might be a more accurate way to phrase the idea: "When recently polled, the consensus among Australians was that only 58% of climate scientists agree that humans are responsible for global warming."

    My guess is that a breakdown by political parties or along rural/urban populations or by the degree of education attained would be much more instructive, albeit potentially embarrassing to certain groups.


    0 0

    [JC] Apologies for the technical jargon. A "US representative sample" is a small group (e.g., a few hundred people) whose demographics are selected so that they represent the entire USA population. For example, one of the demographics is age. If my survey sample was all young people, it wouldn't represent the population as a whole. So I had to make sure the distribution of ages in my sample matched the distribution of ages in the entire USA population. Similarly, a representative sample should match the demographics on gender and income level.

    Fair comment re "average Australian". I'm talking about what you get when you average out the answer among the whole spectrum of Australians. Trying to explain things in simple, plain English introduces imprecision and science communication is always a balancing act between readability/accessibility and technical precision.

  3. John Cook, was the survey you conducted a survey of Australians based on US demographics, or a survey of US citizens based on US demographics?  If the later, on what basis do you extent the results to Australians?

    Re terminology, "consensus" is obviously unsuitable in this context.  The consensus opinion is that opinion least disagreed with across all involved, and which the vast majority can agree with.  Thus it would need to be expressed as a range, and a range that encompasses at least 90% of responses.  On this issue, among the general public that range is likely to be 58% +/- 42% which would be singularly uninformative.  I personally would recommend using popular language, but including a more exact description in brackets, such as:

    "But when the average Australian thinks the consensus is not 97%, but just 58% (mean response), there is clearly a public misconception about what the scientists really think."

    Of course, for all I know, such paranthetic clarrifications may be as bad as mathematical equations in terms of readership.

    0 1

    [JC] The survey of Australians used Australian demographics and the survey of US citizens used US demographics.

  4. It is important that Clive Palmer understands why human greenhouse gas emissions are responsible for global warming. This essay makes it very clear why this is the case, so one would hope that Palmer and his Party (PUP) read this lucid explanation.

    This is particularly important given that PUP may hold the balance of power in the Senate after 1 July, 2014. Clive Palmer has already indicated that his Party is likely to oppose legislation to establish the Government’s “Direct Action” scheme for reducing greenhouse gas emissions. He correctly describes it as costly and ineffective.

    However, he has also indicated that PUP is likely to support abolition of the Carbon Tax and the extensive measures aimed at promoting renewable energy and the independent science-based body responsible for advising government on future carbon reduction targets. The net result of such voting would be to leave Australia without any legislative basis for reducing carbon emissions.

    While this might be a satisfactory outcome for the owners of high emission businesses – of which Palmer is one – it would also ensure that Australia would not meet its treaty obligations to reduce carbon emissions.

    0 0
  5. Riduna@4,

    Based on the recently published details of current Government’s “Direct Action” scheme, my personal opinion is that, for both environment and australian people, it would be better to leave Australia without any legislative basis for reducing carbon emissions, rather than replacing existing Carbon Tax with said “Direct Action”.

    The reason for my opinion is that “Direct Action”:

    - will work against the emission reduction by rewarding polluters (giving them money for the "promise" to reduce emissions that may or may not work in practice)

    - does not create any incentives on the consumer side to reduce/alter their energy usage

    - will cost govts money that they will need to find by cutting some social spending or increasing base taxes (what they are already doing now)

    So, while I agree with you that PUP's voting according to Palmer's vested interests after 1 July, will likely result in the complete alienation of Australia from global mitigation efforts, this result would not be the worst ever outcome. Palmer is a complete sciece denier at the most basic level as we've seen above, but at the same time he also understands the futility (and potential negative economic impact) of ill-constructed "Direct Action".

    0 0
  6. To be pedantic perhaps, Tony Jones did say a group of scientists, not a group of climate scientists, so amongst that group it might possibly be less than 97%

    0 1
  7. The reason why the Australian public think that there is only a 58% agreement between climate scientists is because the debate in the popular media is mostly political where anything seems to be said rather than it being a scientific debate based on evidence. Also, the basic theory behind the scientific argument i.e. increasing greenhouse gases in the atmosphere due to humans burning fossil fuels will lead (and is leading) to global warming which will change the climate, is not being stated often enough in the media.

    It should be fairly easy to prove this theory with some basic physics and chemistry. Most of the debate in the media concentrates on what we are seeing and what it means rather than on the very basis of the theory. If the theory isn't correct then it undermines our understanding of the science of atoms, the electromagnetic spectrum, isotopes, fluid dynamics and chemical reactions. If the theory isn't correct then it actually undermines our understanding of some of the very science that underpins our technological society.

    0 0
  8. Muzz @6, first, you are being very pedantic in that context clearly indicates the scientists in question to be those knowledgable on global warming.  Second, even on the pedantic interpretation, 82% of scientists in general accept the antropogenic origin of recent global warming.  Significantly, the reduction in acceptance comes mainly from scientists who are neither expert in the field, nor active researchers - ie, those least qualified to advise on the topic.

    1 0
  9. I wouldn't waste too much time on Clive Palmer. As a coal mining magnate it's in his own interest to misrepresent climate science. He has vowed to use his party's votes to vote down carbon pricing (the policy of the previous Labor government-he has also withheld his companies' payments under this scheme), but will also oppose the Liberal Party's much-derided Direct Action policy too. Looks as if he just doesn't want action on global warming in any shape or form.

    0 0
  10. Here is a translation of Palmer's thinking, in words we can all understand.

    You'll want to stopper your children's ears. 

    0 0
  11. One of the reasons why people find it hard to accept that they are causing climate change is the fact that they are not actually doing it. They just make the decisions. It is the operation of systems (coal-fired power stations, cars, trucks, aircraft, ships) and actvities such as logging are doing the irrversible damage. People are more likely to respond soundly if they understand what is actually happening.

    0 0
  12. I like the image of 97% of scientists. But the carbon cycle image does not grab the cognitive faculties of the non-analytical person. It requires time spent on it and some abstract understanding. A better image would be a pair of scales, with 350g weight on each tray, to one of which is added 1g of weight. The scales go out of balance, which is the point to be conveyed. (Then perhaps you can add the carbon cycle image).

    0 0
    Moderator Response:

    (Rob P) - Agreed. The same thing was pointed out by another SkS writer. We'll work on it - the scales concept is interesting. We're open to suggestions. 

  13. denisaf@11 Why do you not include natural factors that are thought to have at least some effect such as the PDO, AMO, Milankovich cycles, natural aerosols etc?  Your comment  "People are more likely to respond soundly if they understand what is actually happening." is very valid.  Having been a universit y academic in area of biochemistry for over 30 years  I know from personal experience that getting others to understand scientific  concepts you requires clarity of expression, attention to detail and some humour.  What it does not require is the sarcastic, scathing, patronising and belittling responses so often given by those who consider their view of climate change  is the  only possible view.  I hasten to add that this does not refer to anything you have written in your comment above.

    0 1
  14. Poster @13

    "Why do you not include natural factors that are thought to have at least some effect..."

    There is an interesting issue here Poster. How does one compare different possible processes that have vastly differing degrees of likelihood of being true? Does one simply lump them all together and say 'here is some stuff that might be relevent'?

    Or does one look at each process and say - 'this one is pretty damn certain, where as that is possible but really quite speculative'. If we don't differentiate the likelihood of different things being true don't we create a situation where our ability to evaluate them is compromised?

    0 0
  15. Logically I suppose you might say something like "At present CO2 from human actions is believed to be the prime cause of climate change/global warming but the  precise magnitude of this is, as yet, not established. Similarly  the precise magnitude of the effects of natural events such as the PDO, AMO etc has yet to be determined.  However, as humans can influence the CO2  produced as a result of their actions but probably can't influence natural events to any significant extent, current thinking is focussed more on what we can influence rather than on what we cannot.  That said however, it would be unwise to assume natural events have no effect on climate change/global warming.  Consequently  continued studies of all possible factors is essential.  

    0 1
    Moderator Response:

    [JH] You are now skating on the thin ice of excessive repetition which is prohibited by the SkS Comments Policy. Please read the Comments Policy and adhere to it. 

  16. Poster @15:

    In point of fact the radiative forcings from various natural and anthropogenic causes have been quantified. Here is the graph from IPCC AR5:

    IPCC AR5 radiative forcings

    Climate change/global warming is simply the result of the change in radiative forcing. Thus modern climate change is almost entirely the result of anthropogenic activities.

    Internal oscillations such as PDO, AMO, ENSO, and the like do not affect climate change/global warming unless they have a quantifiable impact on radiative forcing. Mostly they just move energy around in the climate system, which definitely has effects on how humans perceive global warming and how the impacts of warming are spread through the system. Nevertheless such oscillations do not modify climate change/global warming in any fundamental manner.

    1 0
  17. The radiative forcing numbers might not be very legible in the above, so here is the source for the image.

    0 0
  18. emissions vs vulnerability


    You can "hot-link" your image. In this HTML editor, when the image you just created is still selected, chose Insert/Edit link and paste the URL of the image you just created. As I did with the image from our own sks graphics (after Samson et al 2011). I chose a different example, as not to fall victim of excessive repetition policy :)

    My image is hot (so you can click on it to see original). I see no reason why against all images being so hot-linked by default on this site. They are hosted as links in the first place, so it costs nothing to just create an <A> object for user to click and follow that link if desired.

    And my image shows that indeed, the distribution of global warming (due to said oscillations among other factors) is different to the distribution of the causal factors (anthropo emission), an indication that AGW problem is a social problem in the first place - environmental problem in the second place.

    1 0
  19. Thanks for the hotlink advice, chriskoz! Much appreciated.

    0 0
  20. composer. on your radiative forcings,  I thought methane was 24 times more powerful greenhouse gas than CO2

    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)

© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us