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How the OISM Petition Project casts doubt on the scientific consensus on climate change

What the science says...

Select a level... Basic Intermediate

The 'OISM petition' was signed by only a few climatologists.

Climate Myth...

Over 31,000 scientists signed the OISM Petition Project

The Petition Project features over 31,000 scientists signing the petition stating "there is no convincing scientific evidence that human release of carbon dioxide will, in the forseeable future, cause catastrophic heating of the Earth's atmosphere". (OISM)

There are several claims that large numbers of scientists do not agree with the theory of climate change, the best known of which is a petition organised by the Oregon Institute of Science and Medicine (the OISM petition). This petition now appears to be signed by over 32,000 people with a BSc or higher qualification. The signatories agree with these statements:

  • The proposed limits on greenhouse gases would harm the environment, hinder the advance of science and technology, and damage the health and welfare of mankind.
  • There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gasses is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate.

No evidence has ever been offered to support the first statement, and the second statement is in flat contradiction with the scientists who study climate change. There are also valid issues regarding the methodology:

  • The organisers have never revealed how many people they canvassed (so the response rate is unknown) nor have they revealed the sampling methodology, an ironic omission considering how much fuss is made about scientists being candid and making public their methods and data.
  • The petition is, in terms of climate change science, rather out of date.

In the professional field of climate science, the consensus is unequivocal: human activities are causing climate change and additional anthropogenic CO2 may cause great disruption to the climate.

32,000 Sounds Like A Lot

In fact, OISM signatories represent a tiny fraction (~0.3%) of all US science graduates (petition cards were only sent to individuals within the U.S)

According to figures from the US Department of Education Digest of Education Statistics: 2008, 10.6 million science graduates have gained qualifications consistent with the OISM polling criteria since the 1970-71 school year. 32,000 out of 10 million is not a very compelling figure, but a tiny minority - approximately 0.3 per cent.

There are many issues casting doubt on the validity of this petition. On investigation, attempts to undermine the scientific consensus on climate change often appear to have ideological roots, vested business interests or political sponsors. The claims made for the OISM petition do not withstand objective scrutiny, and the assertions made in the petition are not supported by evidence, data or scientific research.

Several studies conducted independently (Oreskes 2004, Oreskes 2007, Doran and Zimmerman (2009), Anderegg et al. (2010), Cook et. al., 2013) have shown that 97% of climate scientists agree that humans are causing the climate to change, and that anthropogenic greenhouse gases are causing global changes to the climate. These views form the scientific consensus on climate change.

Basic rebuttal written by GPWayne

Update July 2015:

Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial


Last updated on 8 July 2015 by MichaelK. View Archives

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Myth Deconstruction

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Please check the related blog post for background information about this graphics resource.


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Comments 26 to 42 out of 42:

  1. BarbaraB@25.

    It can be said that being "quite relaxed about the climate getting warmer" puts you in good company. Some eminent climatologists have also reached that conclusion. Svante Arrhenius (often credited with discovering AGW) and GS Callender (AGW was called the Callendar Effect once-upon-a-time) both thought the world would benefit from warming. Arrhenius (or perhaps a colleague of his) even toyed with the idea of setting fire to coal mines to help it on its way. Then if you live in chilly Sweden you probably would think 'warm' was 'good'. And I'm told it can be nippy in Sussex during an Ice Age, which was Callendar's concern.

    Of course, both are now long dead so their views on the outcome of AGW are a particularly outdated. So maybe they are not such "good company" after all.

  2. BarbaraB...  The challenge here is that it's a little more complex than things just getting a little warmer. A small increase in global mean temperature actually increases the number of hot and extreme heat days per year, which can have strong negative impacts on crop production.

    Then you have to add in what's known as arctic amplification, where the poles heat up faster than the equator. 

    Consider how challenging it is today, with good crop production, to feed 7 billion people on this planet. Up that number to 9 billion and throw in reduced crop production, now you have the recipe for political unrest, wars, and refugees attempting to escape those conditions. 

    Suddenly, a little bit of warming becomes a very big problem.

  3. Rob, In my neck of the woods - upper USA midwest - the issue is more about higher low temps and the consequent higher humidity levels (I gather).  I was speaking with a climate scientist just last week at a an informal meeting and he has been evaluating extreme (2.0+") spring rainfall events.  Six of the last seven years (May-June period) have been outside the 95% probabillity ellipse of a dataset that is approx 104 years old.  We all know the likelihood of that randomly occurring.  These more frequent, and larger spates play out in many negative ways, not the least of which is translocation of soil down the MS River.  There are some serious implications here for ag management (e.g. nutrient application, riparian management) if this trend continues.  I believe he said the temps coming from Canada have been 6 F warmer, as opposed to the 0.5 F warmer from tropical influences.  I can't remember the time frame he was mentioning.  This isn't my area of research, but it clearly is unsettling to this old ecologist.

  4. Not even linking the petition in question makes your article risible. Thank you for proving to everyone how unscientific this website is.

  5. jesse_a_b @29, do you mean to say that the second link in the intermediate article does not work for you?  Or are you merely proving how scientific you are by criticizing based on false, and easilly falsified information?

  6. jesse...  Top of the page, it's right there in red letters that say "OISM."

    We'll now be expecting an apology and an enthusiastic endorsement from you regarding this very scientific website.

  7. Rob,

    the blue link titled "OSIM Petition" leads directly back to here.  The red "OSIM" caption does in fact lead to the petition.  Since you normally provide links that are blue, his confusion is understandable.

  8. franklefkin @32, jesse_a_b may have been merely confused, missing not one, but two links to the petition and that would have been understandable had they merely asked where the link was.  Instead of asking, they described the article as "risible", and decried the absence of a link (of which there were two) as "proving to everyone how unscientific this website is".  An apology is well in order, as also the retraction of the unwarranted opinion about the quality of this website.

  9. I've been following the climate change issue for some time and although This petition does not hide their academic degree list of signatories or their fundamental argument against AGW. They do have peer reviewed research papers giving details if anyone that reads this site is actually interested. I'm not a climate scientist I watch a lot of the skeptics like Dr Roy Spencer and John Christy who seem very well informed. I've never watched a NASA climate scientist speak out so I checked and I found that NASA is a executive government agency and the climate scientists are told to NOT discuss their views publicly (so we actually don't know how many NASA scientists are skeptics). I've also watched a lot of deceit and data manipulation from major players like IPCC (Climategate) and NAOO (2015 data manipulation). I’ve read these reports and I think all this is common knowledge as these events are in Wikipedia if references are necessary.


    [PS] Perhaps try expanding your reading somewhat (here is a good place) and showing some real skepticism (ie critically examine your anti-AGW sources as well as published science).

    Your statement contains numerous errors. Please see the Intermediate version.

  10. jmcookie, you'll agree, of course, that assessing all evidence is essential to the process of being truly skeptical.  Here (from NASA scientists):

    FYI: NASA scientists discuss their work publicly quite often.  Look around a bit on the GISS website--all sorts of outreach, communication, and transparency.

    Compare the professionalism of NASA's scientists and programs with that of Spencer and Christy (who told Congress in 2013 that no warming had occurred in 15 years, contradicting his own data and laughably contradicting the trend in atmosphere+ocean heat content).

    Your choice, though. While it's only human to root for the underdog, the underdog overwhelmingly has a losing record. Those moments when the underdog actually wins are spectacular and memorable. In this case, the underdogs are not actually working together on the science. The "skeptics" have various alternative theories that are neither comprehensive nor cohesive.  Arrayed against the underdogs is a collection of evidence built over 150 years and through hundreds of thousands of tests, both experimental and applied.  The underdogs in this case, like so many others, are slowly being ground beneath the clinking treads of scientific understanding. Join them, if you will. Or start asking questions, engaging the ideas, and considering the evidence as objectively as you can.


    [PS] The statement "I found that NASA is a executive government agency and the climate scientists are told to NOT discuss their views publicly (so we actually don't know how many NASA scientists are skeptics)." would seem to imply that jmcookie think there is a govm't directive to promote AGW, silencing any opposition. This nefarious operation must also extend to climate research in every other country in world. Frankly, I think jmcookie would be more at home with the conspiracy theorists at WUWT rather than here.

  11. Just found a new entry on Snopes about this:

    Not All Climatologists

  12. Hi. I've been visiting SkS for some time now and generally find the explanations of the science of CC a useful balance of technical detail with layperson language. The filtering by knowledge level is a novel and useful tool (I usually read all levels!).

    I've been exploring the topic of consensus and the flip-side, denial. So I've just read both Cook et al 2016 and the "petition paper" by Robinson et al (both of which are linked to in your article but at which I arrived quite indepently).

    It is clear from reading Cook et al and your article above the value of understanding who is providing the opinions. Cook et al finds that the higher the level of expertise in climate science, the greater the level of consensus. Analogies of getting a heart condition checked out by a motor mechanic are relevant when comparing the findings of Cook et al (ie 97% of expert climate scientists agree that climate change is caused by human activity) versus the OISM petition, signed predominantly by non-climate, possibly non-practising, unpublished, general scientists.

    So it is useful that you and other websites, notably the Huffington Post ( have tackled the credentials of both the signatories and the creators of the petition and Robinson et al paper. Thank you.

    However, I think it would also be useful to tackle the paper itself. Climate change is bewildering to non-scientists, and when one comes across a paper as apparently credible-seeming as the Robinson et al paper, it is difficult for a non-scientist to sort the credible science from the rubbish. Robinson et al's theory about solar irradiance looks pretty good on the graphs, and the longer-term fluctuation in earth's temperature also makes our current increases look pretty modest.

    So I've done just enough preliminary digging into those aspects to convince myself that the Robinson et al paper is at best incomplete in its presentation of evidence (for instance, this webpage about solar irradiance, and in reality, deliberately misleading.

    Yes, go ahead and expose the poor credentials or vested interests of those with opinions that contrast the majority view or have a disporportionate influence, but we need to not simply write-off everything that those people say as rubbish simply because of those credentials or interests. The discrediting of those views should also be focused on the validity or otherwise of their scientific claims, backed up with credible science and analysis. I think it is far more powerful to expose the errors or holes in their arguments than to simply call them fraudulent.

    You have all the relevant science within this site. I suggest that it would be a useful counter to the OISM petition and paper for you to list the scientific claims made in the paper and provide links to the relevant science or other references as you did with the list of studies on consensus. Then your debunking of the petition and paper would not need to rest on the absurdity of the perceived size of 31000 signatories as a representative sample. 

    Regards, Kirdee.

  13. Kirdee, I couldn't agree more.  I have been waiting patiently for the actual scientific rebuttal to the paper.  As easily as the information is laid out, I would have thought that a point by point tearing apart of the data and sources used would have come quickly.

  14. Deaner @38, and Kirdee @ 37, you may be waiting a long time for a detailed rebutal of the accompanying paper to the OISM petition.  That is because the paper constitutes a Gish gallop.  It is so dense with cherry picks, data taken out of context and other errors that it would take a paper just as long simply to provide links to related rebutals.  Given that all of the claims can be (and have been rebutted on SkS) in relation to other issues, the time that would be involved in tracing down all the references, and composing a rebutal is not sufficiently well rewarded.

    To give you an idea of what I mean, I will consider just a few claims made by the paper.

    The paper leads with a Sargossa Sea proxy from Keigwin (1996):

    It is a real proxy, and I do not know of any problems with Keigwin (1996).  What I do know (and which should be obvious) is that no proxy from a single location is a proxy of global temperature.  To think it is is as absurd as thinking that temperatures in Darwin, Australia must vary in sync with those of Boston, Massachussets.  Because temperatures in different regions do not vary in sync, when taking a global average they will regress towards the mean.  Large variations will be evened out, and global mean temperature peaks (and troughs) are unlikely to coincided with peaks (and troughs) of individual regions.

    Robinson, Robinson and Soon (hereafter RRS) will have nothing of that, and conclude from a single proxy that:

    "The average temperature of the Earth has varied within a range of about 3°C during the past 3,000 years. It is currently increasing as the Earth recovers from a period that is known as the Little Ice Age, as shown in Figure 1. George Washington and his army were at Valley Forge during the coldest era in 1,500 years, but even then the temperature was only about 1° Centigrade below the 3,000-year average."

    In contrast to their finding, if you look at a genuine multi-proxy reconstruction of Holocene temperatures (in this case 73 proxies from diverse regions), you see that global temperatures have varied within a 1 to 1.5 C temperature range, and that "Current global temperatures of the past decade have not yet exceeded peak interglacial values but are warmer than during ~75% of the Holocene temperature history", including, as it happens, the MWP:

    RRS have created an entirely false impression by using clearly inadequate, and cherry picked, data.

    Next consider their use of Oelermanns (2005) regarding glacer length, which RRS show as follows:

    For comparison, here is the actual figure (2 B) from Oerlermans (2005):

    You will notice that RRS show the figure inverted.  You will also notice that while the all glaciers figure (in red) jogs down towards the end, it is only the "Alps excluded" figure that jogs up at the end, as shown (once allowing for the inversion) by RSS.  From that evidence, they have deliberately chosen the more restricted data, and chosen it because it better fits their narrative (because it is smoother).

    What is worse, they know and neglected the fact that a Oerlermans (2005) used the data to reconstruct global temperatures.  The result is very different from the impression they are trying to create:

    Temperatures are seen to be more or less stable from 1600, with the slight rise starting around 1850 in keeping with what has gone before.  The 20th century, however, is marked by an unprecedented, rapid, rise in temperature.  That has lead to an unprecedented and rapid retreat of glaciers.

    Once again RRS create a false impression by cherry picking the data, and by forcing us to rely on an intuitive, but false understanding of the relationship between glacier length and temperatures (which are modulated by slope and precipitation, factors Oerlermans takes into account but for which we have no information).  Worse, they portray the data from approximately 70 glaciers (ie, the total number of glaciers used excluding those from the Alps) as though it were the full 169 glaciers considered.

    I could go on, but you will already see from my brief treatment of just two points how extensive a full treatment of RSS would be.  You will also have noted the dishonest tactics used repeatedly by RSS in their paper.

  15. Tom Curtis @39 , your first graph of local Sargasso Sea surface temperature proxies, taken from Keigwin, has already been "doctored" by Robinson and associates.

    In ThinkProgress , May 22nd 2012, physicist Mark Boslough relates how Keigwin's original graph had been shorn of "several years of modern measurements at hydrographic station "S" in Bermuda, starting in 1954" (measurements which presumably Keigwin had thought a good modern comparison for the nearby Sargasso proxies) — and these hydrographic measurements were making the denialist case look less impressive.

    He also said the graph had been shifted by 50 years, in a clumsy error by Robinson and associates mistaking the "paleo Now" for the year 2000. ( I do not see that in the graph: but my screen is very small ! )

    In a further enormity, they had added a spot temperature of 23 degrees at the end of the graph — an addition which strengthened the denialist "impression" for the casual reader.   Boslough says the correct figure for that 2006 spot, should be a full degree higher (i.e. 24).   He brought the error to their attention.  And they refused to acknowledge or correct it.

  16. Eclectic @40, the original Station S SST data as shown by Keigwin (1996) Figure 3, is published here.  The data is annual data from 1955 to 1995, with a mean of 23.025 C, a Standard Deviation of 0.2981 C, and a trend of 0.05 +/- 0.08 C/10 years, as determined by simple linear regression.  More recent temperature data (ie, from late 1988 to the end of 2015) can be found here as Hydrostation_S CTD data.  That data comes as profile, with 22 individual profiles over the course of 2015 (and presumably similar numbers for earlier years).  I did not think it worth to the trouble to download 22 seperate files to determine an annual average, but 2015, at least, appears to have a mean around 24 C.

    From this I would say it was perfectly reasonable to use 23 C as the modern value, but the end of the chart should have been marked as 1975 (the mean of the years of modern data).

    ThinkProgress shows a graph of annual means for Station S from 1955 to 2008:

    Clearly if you do use 2006 rather than 1975 as the final value, the modern value would be closer to 24 C than to 23 C.  Using a fifty year mean (1957-2006) would lower the data point to just above 23 C, and would be perfectly valid given that the data from the d18O is presented as fifty year means.

    Given the scale of the graph, it is not possible by visual inspection to determine whether or not the final d18O data point is 1950 (as it should be).

    Overall, I disagree with ThinkProgress about the termination of the graph (which is clearly before 2000).  I agree about removing the modern data, but think it a minor point.  I definitely think that the "modern value" shown should be labeled 1975, given that it appears to be the mean of the instrumental values in Keigwin (1996).  As it is labelled "2006, it should show a temperature much closer to 24 C.  Whether RRS should be considered to have incorrectly labelled genuine modern data, or incorrectly placed correctly labelled data is indeterminate; but in either case they have straightforwardly strengthened the case they are trying to make by misrepresenting the data.

    Thankyou for bringing that to my attention. 

  17. The blog seems to attack common weaknesses of both realists and alarmists. The alarmist assertions, from ambiguous questions, are a commonality. I addition, the % of survey targets delivered a tiny number of respondants.

    Consensus is irrelevant as all scientists should know however, it has been clearly assessed by Von Storche etc, that the relationship between alarmists, the media and consensus in the unqualified dogma of the masses, is a self perpetuating myth. 

    This blog, so far, contributes to the mythology.


    [PS] Sloganeering snipped. Please read and abide by comments policy. This is not optional. Furthermore note that noone claims scientific consensus make the science right, only that the scientific consensus is the only rational basis for policy. 

    If you want dispute something, use appropriate language. Clearly state the claim (with a reference) you dispute so dont have any strawman arguments. Back your criticism with references/data preferably from the peer-reviewed literature. If you just want a rant there are plenty of other forums which welcome such contribution.

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