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Harvard scientists took Exxon’s challenge; found it using the tobacco playbook

Posted on 23 August 2017 by dana1981

Read all of these documents and make up your own mind.

That was the challenge ExxonMobil issued when investigative journalism by Inside Climate News revealed that while it was at the forefront of climate science research in the 1970s and 1980s, Exxon engaged in a campaign to misinform the public.

Harvard scientists Geoffrey Supran and Naomi Oreskes decided to take up Exxon’s challenge, and have just published their results in the journal Environmental Research Letters. They used a method known as content analysisto analyze 187 public and internal Exxon documents. The results are striking:

  • In Exxon’s peer-reviewed papers and internal communications, about 80% of the documents acknowledged that climate change is real and human-caused.
  • In Exxon’s paid, editorial-style advertisements (“advertorials”) published in the New York Times, about 80% expressed doubt that climate change is real and human-caused.

Percentage of Exxon document positions on human-caused global warming: expressing only doubt (red), only reasonable doubt (grey), acknowledging but expressing doubt (black), acknowledging and expressing reasonable doubt (black hatch), and only acknowledging human-caused global warming (cyan). Illustration: Supran & Oreskes (2017), Environmental Research Letters.

Merchants of Doubt

As Oreskes documented with Erik Conway in Merchants of Doubt, tobacco companies and several other industries that profited from harmful products engaged in decades-long campaigns to sow doubt about the scientific evidence of their hazards. As one R.J. Reynolds Tobacco Company 1969 internal memo read:

Doubt is our product since it is the best means of competing with the ‘body of fact’ that exists in the mind of the general public

The results of this new paper show that Exxon followed this same playbook. While the company’s internal communications and peer-reviewed research were clear about human-caused global warming, its public communications focused heavily on sowing doubt about those scientific conclusions.

For example, Exxon scientist Brian Flannery co-authored a chapter of a 1985 Department of Energy report with NYU professor Martin Hoffert concluding that in a “Low CO2” emissions scenario, humans would cause about 2°C global surface warming above pre-industrial levels by 2100, and about 5°C in a “High CO2” scenario. These projections were in close agreement with those in the latest IPCC report nearly 30 years later.


Temperature increase projected in response to rising carbon dioxide levels. Illustration: Hoffert & Flannery (1985), US Department of Energy report.

Yet in a 1997 advertorial in the New York Times opposing the Kyoto Protocol, Exxon argued:

Nations are being urged to cut emissions without knowing either the severity of the problem – that is, will Earth’s temperature increase over the next 50–100 years? – or the efficacy of the solution – will cutting CO2 emissions reduce the problem?

The advertorial included a misleading graph showing that human activities only account for 3–4% of global carbon dioxide emissions – misleading because the natural carbon cycle is in balance. Earth naturally releases a lot of carbon, but absorbs just as much. Human emissions disrupt that balance and hence are responsible for the entire increase in atmospheric carbon dioxide levels:

In another advertorial published in 2000 to raise doubts about a National Research Council climate report, Exxon talked about:

these still-unanswered questions (1) Has human activity already begun to change temperature and the climate, and (2) How significant will future change be?

That advertorial included a misleading chart of Sargasso Sea Temperature often used by climate deniers because it gives the appearance that current temperatures are lower than they have been over most of the past millennium. The chart is misleading for two reasons: the Sargasso Sea is one isolated geographic area that doesn’t accurately represent the entire planet, and the data shown on the graph ends roughly a century ago, excluding most human-caused global warming.

Crucially, Exxon’s own climate science research answered these questions 10–20 years before the company published the misleading advertorials. The scientific evidence clearly indicated that by burning fossil fuels like those sold by Exxon, humans were increasing carbon dioxide levels, which were causing global warming, and that this would continue until we stop adding more carbon pollution to the atmosphere.

These were the conclusions of 80% of Exxon’s peer-reviewed research and internal communications, and yet 80% of its advertorials aimed at the public were filled with expressions of doubt and misleading statements and charts that would make today’s climate deniers proud. Doubt was their product, and Exxon has peddled it fiercely.

The Lawsuits Have Begun

This study comes as ExxonMobil already faces numerous investigations by state attorneys general and class action lawsuits. One lawsuit accuses Exxon of misleading its investors and inflating its stock value by making false statements about the value of its oil reserves (much of which must be stranded if we’re to meet international climate targets), and about how climate policies will impact the company’s finances.

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Comments 1 to 12:

  1. The behaviour of Exxon has been appalling, but the sad reality is not everyone cares. Some people think companies should be free to do and say what they like. Plenty of climate denialists I have come across have this attitude either out of self punishing stupidity or extreme self interest, and these opposites happily cohabit the denialosphere.

    The five laws of human stupidity

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  2. Nigelj:

    A primary difference with Exxon lying about Cimate Change to their stock holders is that it is against  the law.  AGW will reduce the future profits of oil companies (and therefor reduce the stock proce) and it is fraud for them to hide problems like that from the market.  Already coal company investors have lost their shirts.

    Cigarette company lies only resulted in consumers deaths, not monetary losses for stockholders (in fact stockholders benefited from the fraud).  The law strictly protects stockholders from fraud, consumers have to protect themselves.

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  3. Ironically I called Exxon up quite a long time ago. I explained how them supporting my research as part of Oklahoma's Carbon Project would be cost effective. How it has the potential of avoiding these huge legal and public trust problems before they even become an issue. The cheapest investment they ever thought about making. Very similar to when the big insurance agencies invested in timberland years back to hedge their bets, except Exxon wouldn't need to buy those millions of acres of farmland, just support in the training of new farmers to help mitigate AGW. Total cost to them basically less than their petty cash funds. Probably less than their advertising campaign for a day. Certainly a gazillion times cheaper than their law firm retaining fees to fend off lawsuites for being financially, socially and ecologically irresponcible. ie bad citizens


    The arrogance and ignorance I found from their so called "citizenship" division was incredible. Starting with that as an example and considering any company would put their best foot forward in a "citizenship" division ... No wonder they continually make such blunders. It's like they are purposely trying to do the worst possible thing.

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  4. This seems a rehash of old news.  A couple of years ago, there were reports that Exxon had both admitted climate change was real, and that they had as early as ( and since) 1981 engaged in disinformation on the topic.  Right?

    Only recently have they changed their stance on the science.

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  5. interesting read as well:

    Scientific American Oct 2015 Exxon on Climate Change

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  6. Before we jump to conclusions regarding the validity of this study, a few observations
    1) The links to the XOM articles, studies, etc are not easily accessible which makes it difficult to independently ascertain if the classification of the position of each individual paper is a reasonable classification of the position of such paper, ie is the classification assigned a reasonable classification, since it is difficult to link to and subsequently read the article, it is difficult to ascertain the reasonableness of the classification,
    2) A total of 187 papers, articles, studies, etc seems to be an extremely small sample of the total volume of work and internal documents generated by ExxonMobil, Given the size of Exxon Mobil, most would have expected a much larger sample
    3) As noted in #2 above, the sample size is exceedingly small. Was there ex-post screening to the papers used in this classification study.

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  7. Tom @13

    "The links to the XOM articles, studies, etc are not easily accessible"

    What exactly does this mean? Be precise. Nobody else has complained of difficulties. Not even Exxon is actually denying that they produced a large volume of research confirming that we are warming the climate, so your exercise is somewhat pedantic.

    "A total of 187 papers, articles, studies, etc seems to be an extremely small sample of the total volume of work and internal documents generated by ExxonMobil, Given the size of Exxon Mobil, most would have expected a much larger sample"

    I disagree. You are making a false comparison. The correct comparison would be whether 187 climate studies is a represenative sample of total climate studies, not all internal documents. 187 climate studies would seem a lot of climate studies by any standard.

    Also, the Oreskes study doesn't appear to mention anything about using a random sample as such. They simply stated that they used all the publicly available information they could find. I think its safe to assume anything that Exxon tried to hide would not be flattering to them and I doubt Orekses would have been selective, because Exxon would certainly be in a position to easily embarrass them and would quickly do so.

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  8. Michael Sweet @2, yes I agree absolutely, its fraud to hide problems like this from the public. But the point I was making is some  people I know don't even believe in those types of laws.

    The climate issue is intensely political. The hardened denialists look to me to be driven mostly by political motives about corporate freedom and small government etc, and these positions are rigid positions they are reluctant to change. They resent any laws that define how companies process information. I see all this sort of thing in numerous comments on other websites.

    I havent seen a proper study on it, but I'm willing to bet serious money I'm right. This has to be faced for what it is. This website acknowledges the problem but may be clouding it with too many other lesser things at times.

    I'm not sure how you convince such rigid people, however I do believe they tend to be in a minority, and just make a lot of noise.

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  9. I hve a copy of the summarised report by the Director of a branch of Exxon's Research and Engineering science lab, in response to Exxon's request for research into the effect of increasing CO2.

    It's dated Sept 2nd, 1982

    In part:

    "... The consensu is that a doubling of atmospheric CO2 from its pre-industrial revolution value would result inan average global temerature rise of 3.0° - +/- 1.5° C"


    "In summary, the results of tour research are in accord with the scientific consensus on the effect of increased atmospheric CO2 on climate......"

    There can be no question that the top management of Exxon were unaware of the effect of CO2 back in at least the early eighties.

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  10. There are no denialists! The markets know this and that is why supply is gearing up to match foreseen demand!

    It's just normal pause button politics to slow the world down to the pace it can handle turning at!

    The people lead: governments follow! So, who wants to invest in the future? We all have the power to demand change! The old industries are just waiting for certainty.... the economy is just another large momentum system!!!

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  11. The old-industry-investors are just waiting for certainty before reinvesting en-masse I perhaps should have said!

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  12. Tom: In case you haven't found it yet, the supporting data (121 pages) are here:

    This also provides links for source documents, which I quote:

    All analyzed advertorials can be downloaded at:

    All analyzed internal documents can be downloaded at one (or more) of: (ExxonMobil) (InsideClimate News) (Other)

    Most analyzed peer-reviewed documents are cited in full by ExxonMobil (3 exceptions)

    Most analyzed non-peer reviewed documents are cited in full by ExxonMobil (15 exceptions)

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