The Exxon Climate Papers

Written by Andy May,

New York Attorney General Eric T. Schneiderman has accused ExxonMobil of lying to the public and investors about the risks of climate change according to the NY Times and has launched an investigation and issued a subpoena demanding extensive financial records, emails and other documents.

Massachusetts, the US Virgin Islands, and California are also investigating ExxonMobil. It is interesting that all but one of the attorneys general are Democrats. exxon The remaining attorney general is Claude Walker of the US Virgin Islands who is a Green leaning Independent. So, this is a very partisan investigation, carefully coordinated with anti-fossil fuel activists. How much is there to it?

I’ve reviewed the 22 internal documents from 1977 to 1989 made available by ExxonMobil here. I’ve also reviewed what I could find on 104 publications (most are peer-reviewed) with ExxonMobil personnel as authors or co-authors. For some of the peer-reviewed articles I only had an abstract and for some I could find the reference but no abstract or text without paying a fee. Below this short essay is an annotated bibliography of all 22 internal documents and 89 of the published papers. The documents are interesting reading, they fill in the history of modern climate science very well. Much of the current debate on climate change was being debated in the same way, and often with the same uncertainties, in 1977.

Between 1977 and the fifth IPCC report in 2013 ExxonMobil Corporate Research in New Jersey investigated the effect of increasing CO2 on climate. If they withheld or suppressed climate research from the public or shareholders, it is not apparent in these documents. Further, if they found any definitive evidence of an impending man-made climate catastrophe, I didn’t see it. The climate researchers at ExxonMobil participated in the second, third, fourth and fifth IPCC assessment reports making major contributions in mapping the carbon cycle and in climate modeling. They calculated the potential impact of man-made CO2 in several publications. They investigated methods of sequestering CO2 and adapting to climate change. They also investigated several potential biofuels.

The internal documents are generally summaries of published work by outside researchers. Some of the documents are notes from climate conferences or meetings with the DOE (Department of Energy). For many of the internal documents one has to read carefully to separate what is being said by the writer and what he is reporting from outside research. Exxon (and later ExxonMobil) did some original research, particularly making ocean and atmospheric measurements of CO2 from their tankers. But, most of what they produced was by funding research at Columbia University or the Lamont-Doherty Earth Observatory. All of their internal research and the work at Columbia was published as far as I can tell, so it is difficult to accuse them of hiding anything from the public or shareholders.

At the heart of Schneiderman’s accusation, according to the NY Times, is a list of statements made by ExxonMobil executives that he believes contradict the internal memos summarized below. The statements are reported here. In fact, the internal memos and documents listed below, do not contradict the ExxonMobil executives in any way. The internal documents and publications all clearly describe the considerable uncertainties in climate science and align with the executives’ statements. Go to the link to see all of them, two of the most notable are quoted below:

Mr. Ken Cohen, ExxonMobil Vice President for Public and Government Affairs, 2015 (Blog Post):

“What we have understood from the outset – and something which over-the-top activists fail to acknowledge — is that climate change is an enormously complicated subject.

“The climate and mankind’s connection to it are among the most complex topics scientists have ever studied, with a seemingly endless number of variables to consider over an incredibly long timespan.”

Duane Levine, Exxon’s manager of Science and Strategy Development, 1989 (Internal Document #21 below)

“In spite of the rush by some participants in the greenhouse debate to declare that the science has demonstrated the existence of [man-made global warming] today, I do not believe such is the case. Enhanced greenhouse is still deeply imbedded in scientific uncertainty, and we will require substantial additional investigation to determine the degree to which its effects might be experienced in the future.”

Even if there were a contradiction between the executives and the ExxonMobil climate researchers, who is to say which of them is wrong? Free speech is a fundamental individual right in the USA and executives are allowed to disagree with their employees. As University of Tennessee Law Professor Glenn Harlan Reynolds has said in USA Today:

Federal law makes it a felony “for two or more persons to agree together to injure, threaten, or intimidate a person in any state, territory or district in the free exercise or enjoyment of any right or privilege secured to him/her by the Constitution or the laws of the Unites States, (or because of his/her having exercised the same).”

“I wonder if U.S. Virgin Islands Attorney General Claude Walker, or California Attorney General Kamala Harris, or New York Attorney General Eric Schneiderman have read this federal statute. Because what they’re doing looks like a concerted scheme to restrict the First Amendment free speech rights of people they don’t agree with. They should look up 18 U.S.C. Sec. 241.”

ExxonMobil has filed court papers in Texas seeking to block a subpoena issued by the attorney general of the US Virgin Islands Claude Walker. They argue that the subpoena is an unwarranted fishing expedition into ExxonMobil’s internal records.

Environmentalist groups, like the Rockefeller Family Fund and are trying to organize a legal attack against ExxonMobil patterned on the attack many organizations led against the tobacco companies. They feel that their presumed imminent man-made climate disaster is being ignored and they want to make ExxonMobil a scapegoat. As Lee Wasserman (Rockefeller Family Fund) said recently “It’s not really about Exxon.

Mr. Scheiderman may have made the “error of assuming facts that are not in evidence.” He assumes that man-made greenhouse gases are a significant factor in climate change and that the resulting enhanced climate change is dangerous. Neither assertion has been proven. He also assumes that Exxon’s early research proved these assertions to be true, with little or no doubt. Therefore, Mr. Scheiderman believes the Exxon executives’ claims that there is significant uncertainty around the idea of dangerous man-made climate change is a lie. I do not see any proof of dangerous climate change, man-made or otherwise in any of the documents below. In peer reviewed document #55 below, Flannery, et al. in 1985 suggest that the effect of CO2 on climate, based on geological data from the Cretaceous Period, is 50% or less. Internal document #3 indicates concern that there is a “potential problem amid all the scientific uncertainties.”

Along this line of thought, the ExxonMobil court filing against Mr. Walker and the US Virgin Islands says in part:

“… [ExxonMobil] has “widely and publicly confirmed” that it recognizes “that the risk of climate change and its potential impacts on society and ecosystems may prove to be significant.”

Brian Flannery states in published document #66 below in 2001:

“Although we know the human emissions fairly well, we don’t know the natural emissions well at all. Added to this uncertainty is the fact that natural emissions can change as a result of long-term climate changes.”

The key problem is that ExxonMobil management and most, if not all, of their researchers do not think the idea of dangerous man-made climate change has been proven. Further, one of them said in internal document #3 below: “we have time to evaluate the uncertainties even in a worse-case scenario.” This is still true, especially considering the very slow pace of warming over the last twenty years.

In internal document #3 below, they discuss the potential effect of doubling CO2 in the atmosphere and the discussion is instructive. The CO2 level prior to the industrial revolution (roughly 1840-1850) is unknown. They give two possibilities (260-270 ppm or 290-300 ppm). The temperature increase from 1850 to the end of 2015 is roughly 0.85°C from the HADCRUT 4 dataset and the 5th IPCC Assessment reports 0.85°C from 1880 to 2012. The Exxon researchers did not think a clear anthropogenic signal was detectable in 1979, because at that time the total temperature increase from 1850 had not exceeded 0.5°C, their assumed natural variability. So, they thought man-made warming might be clearly detected by the year 2000.

We are now well past the year 2000 and according to the data shown in their Table 6 (Internal Document #3), we are on track with their most benign scenario of a temperature increase of 1.3° to 1.7°C per doubling of CO2 (ECS).   This assumes an initial concentration of CO2 of 265 to 295 ppm and a natural variability of +-0.5°C. The initial CO2 concentration assumption is reasonable, the assumption of 0.5°C for natural variability may be too low.   However, if the assumptions are true, they probably eliminate the possibility of higher climate sensitivity to CO2 (ECS>2°). This is also supported by recent empirical estimates of ECS. There are considerable uncertainties in this approach, but they are important to recognize. We don’t know the CO2 level when we started emitting a lot of fossil fuel CO2, we don’t know the net effect on our climate, and can’t be certain we have seen any impact of man-made CO2 on our climate to date.

Even Brian Flannery, one of the Exxon researchers who has been deeply involved in the IPCC process stated in internal document 22, below: ““While uncertainty exists, science supports the basic idea that man’s actions pose a serious potential threat to climate.” This is the most alarmist statement I could find anywhere, but it still says “potential” and notes that uncertainty exists.

In peer-reviewed paper #25 below, Dr. Kheshgi and Dr. White state in 2001:

“Many previous claims that anthropogenically caused climate change has been detected have utilized models in which uncertainties in the values of some parameters have been neglected (Santer et al. 1996b). In section 5 we have incorporated known parameter uncertainties for an illustrative example by using the proposed methodology for distributed parameter hypothesis testing. The results clearly show that incorporation of parameter uncertainty can greatly affect the conclusions of a statistical study. In particular, inclusion of uncertainty in aerosols forcing would likely lead to rejection of the hypothesis of anthropogenically caused climate change for our illustrative model …”

They are concerned here and in other papers, that the GCM (global circulation climate models) have used fixed parameters for their calculations for variables that actually have a great deal of uncertainty. By fixing these variables across many models, the modelers produce a narrower range of outcomes giving a misleading appearance of consistency and accuracy that does not actually exist.

As Professor Judith Curry has often said there is an uncertainty monster at the science-policy interface. The ExxonMobil scientists are very good, they write well and their superiors in ExxonMobil understand what they are saying. Man-made climate change is a potential problem, but it is shrouded in uncertainty because it is an extremely complex research topic with countless variables. The internal and published documents below show that Exxon has worked hard to define the uncertainty and they have even succeeded in reducing the uncertainty in some areas, especially in the carbon cycle. But still, the remaining uncertainty is huge and it covers the range from zero anthropogenic effect to perhaps 4° or 5°C (see publication #7, Kheshgi and White 1993) to this day. Not much different than in 1977 when they got started.

I’ll conclude this post with a quote from internal document #11, the 1982 Exxon Consensus statement. I think it speaks well for ExxonMobil and puts Schneiderman (and many in the media) to shame:

“As we discussed in the August 24 meeting, there is the potential for our research to attract the attention of the popular news media because of the connection between Exxon’s major business and the role of fossil fuel combustion in contributing to the increase of atmospheric CO2. Despite the fact that our results are in accord with most major researchers in the field and are subject to the same uncertainties, it was recognized that it is possible for these results to be distorted or blown out of proportion.

Nevertheless the consensus position was that Exxon should continue to conduct scientific research in this area because of its potential importance in affecting future energy scenarios and to provide Exxon with the credentials required to speak with authority in this area. Furthermore our ethical responsibility is to permit the publication of our research in the scientific literature; indeed to do otherwise would be a breach of Exxon’s public position and ethical credo on honesty and integrity.”

This is the only thing I found in the internal memos that was not published. In 1982 they thought the media might distort their research results or blow them out of proportion (the Uncertainty Monster). Well, that certainly happened. For science to work properly, research outcomes cannot be dictated. All interested parties must be allowed to investigate the problem and publish their results. They must have access to data, computer programs and models that are publicly funded. But, above all, they should not be punished, jailed, intimidated or sued because they are skeptical of a popular scientific thesis. They should be judged only on the quality of their scientific work and not who they work for or who funds them.

This post is excerpted from a longer post The Exxon Climate Papers, that includes links and annotations to 89 documents, including internal documents and published papers.

Bio notes:   Andy May worked for Exxon from 1980 to 1985.  During part of that time he worked on the Natuna D-Alpha project discussed in some of these documents.  He did not work at either the Florham Park, New Jersey Research laboratory or the Linden, New Jersey laboratory where the climate research was done. The views expressed in this essay and bibliography are his own. This was written in his spare time and he received no compensation from anyone for writing and posting it.

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