Posted on 19 October 2017 by Ari Jokimäki

Elsevier's journal Renewable and Sustainable Energy Reviews published a paper in 2013 (Florides et al. 2013, "F13" from now on) which we found problematic. We analysed the paper and communicated our findings to Elsevier. Our main findings were that much of F13 text was copy/pasted from other sources without proper attribution and that F13 contained many false claims. In this series of posts I'll go through the problems in F13 and in Elsevier actions. There are four posts:

• The F13 files, part 1 - the copy/paste job
• The F13 files, part 2 - the content analysis
• The F13 files, part 3 - the reference list analysis and other problems
• The F13 files, part 4 - dealing with Elsevier

Part 2 - the content analysis

While we were reading F13, a few problems leapt out quickly. With more thorough inspection we found pervasive problems in F13. We realized that a normal style of comment paper where we comment on some main points of F13 wouldn't be a good approach in this case. Instead we decided to try to quantify the amount of misinformation in F13. To do this, we needed to analyse the contents of F13 for flaws, misrepresentations, logical fallacies, etc. However, a comprehensive rebuttal of F13 would have taken much time and far exceed the F13's size, so we limited detailed analysis to F13 chapters 1 and 2, which we analysed paragraph-by-paragraph. After this, we calculated the percentage of misinformation within the two analysed chapters.

Results of the content analysis

Of 27 paragraphs in the first two chapters, 19 (about 70%) contained problems, and 10 (about 37%) contained problems we claim are serious. Altogether, we found 43 individual problems from those two chapters alone. The figure below shows the problem counts for each paragraph.

On average, there are about 1.6 problems in each paragraph. Highest problem count within a single paragraph is four, which occurs in two of the paragraphs. In addition there are five paragraphs which all have three different problems. Only 8 of the 27 paragraphs didn't show obvious problems.

We identified different types of problems in numbers of paragraphs:

• misleading discussion (15 occurrences)
• failure to cite relevant research (6)
• logical fallacies, mainly strawman argumentation and cherry picking (7)
• non-peer-reviewed references (4)
• outdated discussion (3)
• misrepresentation of references (3)
• miscellaneous, such as false claims and poor methodology (5)

The detailed paragraph-by-paragraph analysis is presented in Appendix A, in the same form we sent to Elsevier with our comment paper.

F13 and climate models

F13 paints a picture that the effect of CO₂ on climate is based solely on climate model simulations. They attack this strawman by cherry-picking statements to make climate models seem worthless. They ignore the fact that climate models have showed remarkable prediction skill, as is quite clearly shown in one of F13 primary sources of information, IPCC AR4 [3]. Then they just declare the effect of CO₂ on Earth’s climate negligible.

F13 argumentation on this issue is flawed because they completely ignore the empirical research on the climatic effect of CO₂. The enhanced greenhouse effect due to increase in atmospheric CO₂ concentration has been seen in observations [3, Chapter 2.3.8]. They also ignore the empirical research on climate feedbacks, such as water vapor [3, Chapter 3.4.2]. Furthermore, contrary to how F13 discuss the issue of climate models, IPCC AR4 [3, FAQ 8.1] says:

“There is considerable confidence that climate models provide credible quantitative estimates of future climate change, particularly at continental scales and above. This confidence comes from the foundation of the models in accepted physical principles and from their ability to reproduce observed features of current climate and past climate changes. Confidence in model estimates is higher for some climate variables (e.g., temperature) than for others (e.g., precipitation). Over several decades of development, models have consistently provided a robust and unambiguous picture of significant climate warming in response to increasing greenhouse gases.”

F13's claimed picture of climate models is exactly the opposite of the current understanding in mainstream climate science.

Discussion

We used IPCC AR4 [3] as a reference as much as we could because it seems to be the main reference in F13. As we have shown, F13 have ignored much evidence from a source they themselves referenced.

Some problems we identified might be debatable but we believe that most of the problems we identified are solid findings. Furthermore, as F13 seems to have many problems, we think that it is probable that we have not identified all of the problems within the two analysed chapters, so the number of problems we identified seems to be a minimum. Some paragraphs in F13 contain only minor problems, which is why we included a rough classification of severity of problems (minor/major) for each paragraph. This classification has some subjectivity but we wanted to acknowledge that not all paragraphs with identified problems are equally problematic.

It should be noted that most of the texts in this post are from our comment paper we sent to Elsevier.

Appendix A. The paragraph-by-paragraph analysis.

F13 Chapter (ch) 1, Paragraph (pg) 1: F13 imply that warm climates have been good for mankind, but that is an oversimplification. The rate of climate change is more harmful than the climate after the change [e.g. 10]. As far as we know, the rate of past climate changes have been very slow compared to the current change [11] [3, FAQ 6.2], and yet past changes are known to have been associated with mass extinctions of species [12] [13]. Furthermore, research suggests that in the more recent past, mankind has suffered from climate changes [e.g. 14, 15]. All this argues that current climate change might at least be potentially harmful.

Problems: misleading argumentation.
Severity: minor.

F13 ch 1, pg 2: F13 misrepresent the history of the discovery of global warming, CO₂'s role and that of the IPCC. First, the climatic effect of CO₂ was known before the increase in atmospheric CO₂ concentration was observed [e.g. 16] and well before the IPCC was created (in 1988). Second, the IPCC only assesses and summarizes contemporary scientific research [17]. If scientific research shows that CO₂ has caused recent global warming, then it is the IPCC's duty to report so. Most of the work of the IPCC is done by volunteer scientists from around the world, supported by a tiny UN secretariat.

Problems: 2 x misleading argumentation.
Severity: minor.

F13 ch 1, pg 3: Contains no obvious problems.

F13 ch 1, pg 4: F13 promote the Svensmark (2012) [18] hypothesis that past climate changes were driven by Earth’s encounters with Milky Way’s spiral arms. This alternative hypothesis was tested by Overholt et al. [19] with improved spiral structure data and found that the claimed correlation with Milky Way’s spiral structure and Earth’s climate did not exist. This research, published in a very well-known astronomy journal, is ignored by F13 and Svensmark [18].

F13 also suggest that temperature fluctuations in Vostok ice cores are due to Earth’s orbital
parameters, a misleading halftruth. Mainstream climate science ascribes the timing of the glacial cycles to Earth’s orbital parameters while the amplitude of the temperature change is affected by feedbacks, for example from greenhouse gases amplifying the initial temperature change [e.g. 20].

Problems: misleading argumentation, failure to cite relevant research.
Severity: major.

F13 ch 1, pg 5: Contains no obvious problems.

F13 ch 1, pg 6: F13 cite a non-peer-reviewed book chapter by the F13 authors (their reference 5) that contradicts the mainstream on an issue for which there exists much proper scientific material such as IPCC AR4, Chapter 2.7 [3].

Problems: non-peer-reviewed references.
Severity: minor.

F13 ch 1, pg 7: Contains no obvious problems.

F13 ch 2.1, pg 1: Contains no obvious problems.

F13 ch 2.1, pg 2: Here, F13 mention that the growth rate of atmospheric methane has been in decline since 1990s, but this is only partially true. Growth rate of atmospheric methane did decline, but it stabilized in late 1990s, and began increasing again in 2007 [21, i.e. IPCC AR5, ch. 2.2.1.1.2., which was not available for F13, but references in the chapter in question were].

Problems: outdated discussion.
Severity: minor.

F13 ch 2.1, pg 3: Contains no obvious problems.

F13 ch 2.1, pg 4: Here F13 misrepresent IPCC AR4 [3 , Chapter 1.3.3]:

"Detection of climate change is the process of demonstrating that climate has changed in some defined statistical sense, without providing a reason for that change."

Here is how F13 say it:

"IPCC reports that climate has changed in some defined statistical sense and
assumes that the reason for that is anthropogenic forcing."

(Emphasis by us in both quotes.) F13 have taken a statement about climate change detection from IPCC AR4 [3] and distorted it to make it seem that the attribution of climate change is just guesswork in IPCC AR4 [3]. Detection seeks to detect if a climate change is happening, and attribution seeks to assign causes to climate changes. In any case, the IPCC conclusions are based on numerous attribution studies that consistently show that most of the recent global warming and resulting climate change is due to actions of mankind. The IPCC does not make the assumption that F13 claims.

Problems: misrepresenting references.
Severity: major.

F13 ch 2.1, pg 5: Here F13 have also misrepresented IPCC [3, Synthesis report, Chapter 2]:

“Observed patterns of warming and their changes are simulated only by models that include anthropogenic forcings.”

F13 have made an addition that distorts the meaning of the sentence:

“...and hence the observed patterns of warming and their changes are simulated only by models that include anthropogenic forcing and not external forcing.”

The IPCC statement is somewhat ambiguous. The statement should mention that observed patterns are simulated only by models that include anthropogenic forcings and other forcings, but not when models omit anthropogenic forcings. In climate science, anthropogenic forcing is traditionally considered as an external forcing [22], but F13 misrepresent this.

Problems: misrepresenting references.
Severity: minor.

F13 ch 2.1, pg 6: Here F13 falsely claim that anthropogenic global warming is only a result of climate model simulations. Much observational data supports the results of the climate models as discussed in the main body of our paper.

F13 also claim that: “ Very important natural factors, like the effect of water vapor and clouds, are not even mentioned in this table. ” The IPCC’s table in question lists only forcing factors, not climate feedbacks, such as water vapor and clouds, handled elsewhere [3, Chapter 8.6].

Next, F13 cherry-picks a statement on uncertainty in climate models from a 2001 report by National Research Council (NRC). Elsewhere F13 have relied on IPCC AR4 [3] for information on mainstream climate science and, as we discussed in the main body of our paper, F13's opinion on the quality of climate models is exactly the opposite to mainstream climate science, but without credible evidence.

Problems: false claim, misleading argumentation, logical fallacy, outdated discussion.
Severity: major.

F13 ch 2.1, pg 7: Here F13 make a claim:

“If the governing models for the climate system are derived without any sound theoretical background given that we do not have a good understanding of all related physical factors, computer simulations become merely a form of data curve fitting.”

This false conclusion rests on their falsehoods in previous paragraphs. F13 go on to further suggest that models should be validated against real world data. This suggests that they have not studied the issue much, because models are routinely validated against real world data, as we have discussed in the main body of our paper.

F13 cite a non-peer-reviewed book (F13 reference 14) on this issue, ignoring the vast scientific literature available.

Problems: false claim, misleading discussion, non-peer-reviewed references.
Severity: major.

F13 ch 2.1, pg 8: Here F13 cite a non-peer-reviewed blog post on the issue of comparing climate model simulations to observations, again ignoring much scientific literature [3, FAQ 8.1? 3, Chapter 8].

Problems: non-peer-reviewed references.
Severity: minor.

F13 ch 2.2, pg 1: F13 suggest that:

“Studying past records is an undeniable tool to test the assumption that CO₂ is the main driving factor for the earth climate.”

This is a straw-man argument because mainstream climate science does not make that assumption. CO₂ is thought to be one forcing factor among others. Many past climate changes cannot be fully explained without CO₂ forcing, making it a major “control knob” for climate change.

F13 cite a temperature reconstruction from Greenland showing that 11th century temperatures were higher than modern temperatures and argue that this represents the whole Northern Hemisphere, but there are many more complete Northern Hemisphere temperature reconstructions. They usually show the times around 11th century somewhat cooler than modern times [3, Chapter 6.6]. The Medieval Warm Period (MWP) shows strongest in the Northern Atlantic region, which makes it possible to select local reconstructions which show the MWP warmer than present.

According to current understanding there have indeed been warmer times than the present such as the Holocene climate optimum, but past natural climate states and changes do not invalidate modern anthropogenic climate change. Modern temperature change is unaffected by the temperature of medieval times, although understanding past temperatures helps improve models.

F13 try to tie Greenland’s local climatic behavior to CO₂, but this is another
straw-man argument because local temperature changes, in Greenland or in any other place, are not expected to match atmospheric CO₂ record exactly. Internal variability in climate system can easily mask the external forcing from greenhouse gases, when looking at local temperatures. This is especially so in Greenland, where there is a strong climatic influence from Atlantic Ocean circulation changes.

Problems: 2 x logical fallacy, failure to cite relevant research, misleading discussion.
Severity: major.

F13 ch 2.2, pg 2: Contains no obvious problems.

F13 ch 2.2, pg 3: F13 analyse temperature and CO₂ in Vostok ice core by using only two age data points. Based on that, they claim:

"It is clear (see circled points) that the temperature increase by natural causes precedes the CO₂ concentration increase."

They mention nothing about ice core uncertainties or that it might be unwise to compare two datasets formed years apart from each other in this rapidly evolving field. For example, age models are likely to be different making F13 comparison meaningless (F13 ref. 36, Jouzel et al. 2008, mention that their dataset has a new, more accurate dating). It is also strange that their whole analysis consists of circling a few data points on a graph while they have the data and could do a proper analysis. However, as a review paper, F13 should have cited available research on the lead/lag situation between CO₂ and temperature [e.g. 23].

Furthermore, mainstream climate science is well aware that in palaeoclimate data CO₂ seems to lag temperature at initiation of climate changes. Past climate changes have usually been initiated by some other causes and atmospheric CO₂ has then started to change as a feedback. Shakun et al. [24] have demonstrated that the increase in CO₂ followed an initial Antarctic warming (itself likely driven by orbital forcing) but the overwhelming majority of the subsequent temperature increase followed the CO₂ increase.

Problems: faulty analysis, failure to cite relevant research, misleading discussion.
Severity: major.

F13 ch 2.2, pg 4: Here F13 discuss proxy data of millions of years ago. They cite a few points where certain proxies show CO₂ and temperature behaving differently. From this they leap to a conclusion that CO₂ does not affect temperature. There are at least two things wrong in F13’s approach: 1) they do not consider large uncertainties that are present in proxies from millions of years ago, 2) they do not consider that there are other factors affecting climate in addition to CO₂. This is a form of strawman argumentation because F13 try to make it look like that mainstream climate science claim that every climate change is driven solely by CO₂.

After this F13 quote-mines their reference [25] (Kürschner, 2001) to make it seem that their reference would agree with them in their erroneous conclusion. Even the opening summary paragraph in Kürschner (2001) [25] states:

“How long have CO₂ and climate been linked? At least 300 million years, according to the results of a neat technique that exploits the relationship between concentrations of CO₂ in the atmosphere and pores in leaves.”

It is also misleading that F13 treat Kürschner (2001) [25] as if it would contain original research while it is only a news article on Retallack (2001) [26].

F13 also omit relevant research, such as [27], [28], [29], [30], etc.

Finally, F13 make a mistake on Kürschner’s gender. F13 refer to Kürschner as “she” but Wolfram Michael Kürschner is not.

Problems: logical fallacy, 2 x misleading discussion, misrepresenting references, failure to cite relevant research, a minor mistake.
Severity: major.

F13 ch 2.2, pg 5: See the discussion on the previous paragraph. F13 make here similar faulty conclusion based on strawman argumentation.

Problems: logical fallacy, misleading discussion.
Severity: major.

F13 ch 2.2, pg 6: Contains no obvious problems.

F13 ch 2.3, pg 1: The discussion of climate sensitivity in F13 (chapter 2.3) is strange for a review paper. First, they cite many results without giving details of the references in the reference list. Names given as sources of the references are well known for publication records that systematically contradict mainstream climate science results. Results mentioned by F13 are from the low end of climate sensitivity estimates and mainstream climate science results are only briefly mentioned and even then in a demeaning manner. F13 does not mention that flaws have been found [e.g. 31] from the climate sensitivity related works of the researchers F13 cite. However, without proper references it is of course difficult to demonstrate the exact errors.

F13 do give details to one reference but it is a non-peer-reviewed document (F13 ref. 28).

Problems: references missing, misleading discussion, failure to cite relevant research, non-peer-reviewed references.
Severity: major.

F13 ch 2.4, pg 1: F13 argue that warming from increased atmospheric CO₂ concentration would not cause atmospheric water vapor concentration to increase and thus cause further warming as a positive feedback to the original warming. In the numerous studies on this issue, climate models match water vapor feedback observations [3, Chapter 8.6.3.1 and Box 8.1]. F13 mention none of these studies but base their argument only on one old paper [31].

F13 present a figure from IPCC AR4 [3] that shows radiative forcing factors of Earth’s climate. F13 note that the figure does not mention water vapor and clouds, which they seem to think puts climate models into doubt. Apparently F13 have not understood that the IPCC’s figure in question shows only radiative forcing factors, not feedbacks. Climate models do include feedbacks, such as that of water vapor. IPCC AR4 [3] also discusses this issue in Chapter 8.6.3.1 and in Box 8.1.

Problems: failure to cite relevant research, outdated discussion, misleading discussion.
Severity: major.

F13 ch 2.5, pg 1: F13 claim that near future CO₂ concentrations are not directly dangerous to human life. That is a straw man argument, because mainstream science does not claim that future concentrations would be directly dangerous to human life.

Problems: logical fallacy.
Severity: minor.

F13 ch 2.5, pg 2: Contains no obvious problems.

F13 ch 2.5, pg 3: F13 argue that CO₂ is beneficial to plant life because many CO₂ enrichment studies support such a conclusion. This is a partially true but misleading analysis because plant growth is affected by other climate factors, such as change in temperature, precipitation, and cloudiness. F13 look only one aspect of this complex issue ignoring the other aspects. For example, an increase in CO₂ will not grow corn in the Sahara without more water. Furthermore, factors affecting plants change by location of the plants (near the equator drought is becoming an issue while in high latitudes some plants are expected to grow more).

Problems: misleading discussion.
Severity: minor.

F13 ch 2.5, pg 4: Continues the same argumentation as the previous paragraph.

Problems: misleading discussion.
Severity: minor.

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