This is part 1 of a two part book review.
A few years ago, a man named Gregory Wrightstone appeared in several of the Facebook groups I participate in. He participated in debates with other members over issues related to climate change, frequently using graphs that he had made. It turns out he was working on a book, and as best I can tell, he was testing his content in debate groups to hear objections to his claims before self-publishing the book. That's a bit of speculation on my part, but I noticed that his book sometimes was changed from what he had posted in the discussion groups, and I like to think that he altered his arguments as a result of conversations with others. He self-published his book under the sufficiently political title, Inconvenient Facts: The Science Al Gore Doesn't Want You to Know.[1] The not-so-subtle implication here is that Al Gore misrepresented the facts and science of climate change and doesn't want you to be informed, but Mr. Wrightstone is going to set us straight on the science. It became readily apparent, both in Facebook discussions and in reading his book, that he wasn't really going to live up to the promise of the title. The book is short on facts and long on saying what's convenient for the fossil fuel industry.
Which isn't surprising because Mr. Wrightstone has a masters degree in Geology, and he built his career working for the fossil fuel industry. In particular, he looked for natural gas in the Marcellus Shale in Pennsylvania. He has done no research in climate science, has written no peer-reviewed papers on the subject, and is not an expert in climate in any way. But he self-published a book, and he marketed it well enough to become fairly well-known, well enough that now he is leading the CO2 Coalition - a political group designed to promote policies that will delay the transition away from fossil fuels.
His book has been popular, though, and I've seen aspects of it appear on the CO2 Coalition website. The book is structured as 60 "facts" that he believes should lead us to reject what the vast majority of climate scientists say so that we can continue to buy natural gas extracted from the Marcellus Shale (okay, that was a jab, but I hope you can see the conflict of interest here). Many of these "facts" are partly or mostly true. But he draws demonstrably wrong conclusions from most of them. I thought it would be helpful to review the book by examining a representative sample of these "facts." I think it will be best if I group them by topic and respond to them with reference to the numbers he gave the facts. I don't plan on being exhaustive, only representative. Let's start with what he says about CO2 and paleoclimate. In this post, I'm going to cover a representative number from the first two chapters of the book.
Inconvenient Fact 1
The first "fact" is "Carbon Dioxide is not the primary Greenhouse Gas." Certainly by concentration, this is true. Water vapor is much more prevalent in the atmosphere than CO2 (with exception of arid climates). However, Wrightstone gets a lot of what he says about CO2 and water vapor wrong. Here is the central problem from which the rest seems to depend. He writes in his introduction, "The main driver of greenhouse warming—water vapor—is often completely ignored." There are two problems here. First, water vapor is not a "driver of greenhouse warming," let alone the "main driver." Water vapor concentrations are dependent on temperature. It precipitates out of the atmosphere every time it rains or snows. So water vapor cannot build up in the atmosphere. This means it cannot be a "driver" of greenhouse warming, but it can be a feedback that amplifies warming caused by something else, like CO2, methane and other gases that can build up in the atmosphere and act as drivers of climate change.
The second thing wrong here is he says that water vapor is "often completely ignored." This again is absolutely wrong. It may be "ignored" as a driver of climate change, but that's only because it's not a driver of climate change. However, it is a potent feedback of climate change, and it is not ignored as such. In fact, estimates of equilibrium climate sensitivity (ECS) from CO2 alone are only about 1 C for doubling CO2. But given feedbacks, like those from water vapor, most estimates of CO2 are in the neighborhood of 3 C for doubling CO2. Water vapor is not ignored at all.
So it's somewhat puzzling that he would then say, "Downplaying or disregarding water vapor, or assigning too large a magnitude to feedbacks such as the water-vapor feedback that is thought to amplify the direct warming from CO2, serves to overemphasize Man’s contribution to greenhouse warming." How is it that scientists both disregard water vapor and assign too large a magnitude to the water vapor feedback? He doesn't say; nor does he justify this claim. But scientists estimate that climate sensitivity for doubling CO2 is between 2.6 C and 3.9 C. This puts limits on the magnitude of the water vapor feedback.
Inconvenient Fact 2
The second "fact" is "The warming effect of CO2 declines as its concentration increases." Here, Wrightstone correctly notes that the relationship between an increase in CO2 and change in temperature is logarithmic. Better stated, though, the relationship between an increase in CO2 and a change in radiative forcing is logarithmic. The relationship between a change in radiative forcing and global mean surface temperature is linear. This is true, and it's built into all models and estimates of sensitivity. Scientists say that the climate will warm by a set amount every time that CO2 doubles, with the best estimate being about 3 C. So if we start with preindustrial levels at 280 ppm, then temperatures should reach equilibrium with 560 ppm at 3 C warmer than preindustiral levels. You would have to double CO2 again to 1120 ppm to increase temperatures by another 3 C. And yet, Wrightstone asserts, "This inconvenient fact, important though it is, is kept very well hidden and is rarely mentioned, for it undermines the theory of future catastrophic climate change." This very strange. It is never hidden. It's advertised that ECS is about 3 C. And this does not undermine anything about anthropogenic climate change, whether you called "catastrophic" or not. The IPCC says we can avoid some of the worst effects of AGW by limiting warming to 2 C above preindustrial levels, and better if we keep warming below 1.5 C. If we continue emitting GHGs at current rates with no mitigation policies, warming could reach 4 C by 2100. This is a significant amount of warming.. To put this in perspective, the difference between the last glacial maximum (LGM) and the Holocene Thermal Maximum (HTM) is only about 6 C. An increase of 4 C is basically two-thirds of the difference between climate when Canada was covered with a thick ice sheet and climate today.
Wrightstone then published a graph attributed to "Monckton 2017" that shows expected warming from CO2 alone, ignoring feedbacks. But of course we do not live in a world that has no feedbacks. In the world we live in, there are factors (like water vapor!) that amplify the warming signal from CO2 and other greenhouse gases. So on the one hand, he wrongly suggests climate scientists ignore the effect of water vapor, but then when it is convenient for him, he does precisely that. He ignores the effect of water vapor amplifying the warming signal from CO2.
Inconvenient Facts 3-4
The next four "facts" are all generally the same; he wants to convince us that CO2 is alarmingly low. I'll treat 3 and 4 together then move on to the next two. He writes, "First and foremost, CO2 is plant food" (f. 3) and because CO2 reached ~180 ppm in the last glacial maximum, "In the last four ice ages, the CO2 level was dangerously low" (f. 4). Aside from the alarmism, these facts contains a lot of information that few would disagree with and aren't in any way "inconvenient" for climate science (or Al Gore). But Wrightstone does get some of this wrong. He says, "Current levels are an incredibly small percentage of the atmosphere, albeit an important one, as advanced plant life could not survive without at least 150 ppm. As we shall see, that 150 ppm 'line of death' is dangerously close to recent concentrations." What Wrightstone is getting at here is that ice core data shows that CO2 was as low as 180 ppm during the last glacial maximum.
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| Temperatures and Forcings for Last 800,000 Years |
The narrative Wrightstone apparently wants to sell you is that fossil fuel emissions are good because they potentially saved us from the extinction of life on earth. Who's to say that the next glacial maximum would take CO2 levels below 150 ppm and kill us all? Thankfully we have the fossil fuel industry to fix this problem for us. I know I sound facetious in saying this, but this is precisely the rhetoric he uses. I'm not misrepresenting him. In his book, he says:
Bear in mind that, before we began adding CO2 to the atmosphere, we weren’t sure that we wouldn’t cross that critical 150-ppm threshold during the next glacial period. (That period may be coming sooner than we think.)
But this is just alarmism. Following the last glacial maximum CO2 levels rose to about 280 ppm and human civilization has altered the planet in countless ways, not least of which is the industrial revolution. But more importantly, there is no "line of death" at 150 ppm. Life has survived through lower CO2 in the past. Several studies now show that during the early Permian,[2] the earth endured about 1 million years at ~100 ppm. Several other studies show plants able to grow to some extent with CO2 as low as 30-40 ppm.[6][7] Now make no mistake. If CO2 levels dropped below 150 ppm, this would be a significant climate stress that would upset the current balance between C3 and C4 plants and have numerous negative consequences, especially for some C3 annuals.[8] The cooling associated with that reduction in CO2 would put pretty much all of Canada under a thick blanket of ice. We do not want another glacial maximum. But we are also not in danger of returning to one (despite Wrightstone's speculations). The climate threat the planet is facing is the consequences of too much much CO2, not too little CO2.
Underlying this "fact" is the notion that if "CO2 is plant food," then the more CO2 the better. But that's simply bad logic. There is such a thing as too much of a good thing. Take "people food" as an example. We need food to survive. If you're healthy and expend 2200 calories per day, you need to eat 2200 calories per day to maintain your health. If you don't eat enough calories, you'll lose weight and eventually suffer from health complications. If you eat too many calories in a day, some of that calorie surplus will be converted to fat, and over time, this can become unhealthy as well. Gaining weight is a symptom of too much of a good thing. Likewise, a warming planet is a symptom of too much CO2. The carbon cycle has become a net source because of human emissions, and the surplus of CO2 is warming the atmosphere and oceans and acidifying the oceans.
Inconvenient Facts 5-6
These two facts are pretty much just a rehash of the last two on a different time scale, but with ramped up alarmism over geologic time scales. Over geologic history, there's a "140-million-year trend of dangerously decreasing CO2" (f.5) and so "Our current geologic period (Quaternary) has the lowest average CO2 levels in the history of the Earth" (f. 6). The first of these is likely true. The second certainly not true. And notice the ramped up alarmism in these "facts:"
It should be obvious to impartial observers of the long-term data that, rather than experiencing excessively high levels of carbon dioxide, we are in fact in a period of CO2 starvation.
Much of what Wrightstone says in these "facts" is misinformed, and it's at best a superficial reading of a very select portion of paleoclimate literature. Far more likely, this is just a rehash of contrarian talking points that he repeats without checking the sources at all. Wrightstone appears to be using one graph, which is the GEOCARB III model published by Berner in 2001. I've written extensively on this, and I don't want to duplicate that content here. But for a survey on scientific literature on the paleoclimate of the Phanerozoic, see
here. For a treatment of the proxy evidence for CO2 and the effects of both solar evolution and CO2 on radiative forcing, see
here (see graph below). To see an exercise showing how the GEOCARB III model would be graphed in terms of radiative forcing accounting for solar evolution, see
here. For a summary of the multiple ways contrarians misuse the Berner CO2 and Scotese temp graphs, see
here.
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| CO2 and Radiative Forcing Over the last 420 Million Years |
It may well be true that overall there has been a decrease in CO2 concentrations over the last 140 million years. However, the GEOCARB III carbon model is not the best place to go to see that any longer. Multiple studies show CO2 proxy data with sufficient resolution to show that it's likely the case that CO2 was higher 140 million years ago, and concentrations have been decreasing due largely due to tectonic forces. Simply stated, forces of erosion and biological processes put carbon on the ocean floor, which sequesters carbon. As the ocean floor is subducted under continents, some of it gets expelled back into the atmosphere in volcanic eruptions. But more carbon is being removed than is being added on geologic time scales. However, we've also seen "rapid" increases in CO2 from eruptions like the Siberian Traps 250 million years ago (these "rapid" emission rates were far slower than the rates humans are emitting CO2 today).
But Wrightstone has not done his homework when he claims that "our current geologic period (Quaternary) has the lowest average CO2 levels in the history of the Earth." Proxy evidence shows that in the early Permian,[2] CO2 levels dropped to perhaps 100 ppm for 1 million years. A good portion of the Permo-Carboniferous glaciation was colder than today and likely had CO2 levels that were lower than the Quaternary. And before the Phanerozoic, the earth has experienced "Snowball Earth" episodes. During the Huronian Glaciation, cyanobacteria began to photosynthesize, and as their populations grew, they removed enough CO2 from the atmosphere that the earth became a giant snow ball, with ice covering the earth possibly down to the equator.
Conclusion
This section of Wrightstone's book is heavy on Geology, and we would expect this section of his book to be largely accurate, given his training in Geology. However, we've seen here that even where Wrightstone would be expected to be the most qualified, he misrepresents many of these "facts," and it doesn't get better from here.
References:
[1] Wrightstone, Gregory. INCONVENIENT FACTS: The science that Al Gore doesn't want you to know . Mill City Press. Kindle Edition.
[2] Montañez, I., McElwain, J., Poulsen, C. et al. Climate, pCO2 and terrestrial carbon cycle linkages during late Palaeozoic glacial–interglacial cycles. Nature Geosci 9, 824–828 (2016). https://doi.org/10.1038/ngeo2822
https://www.researchgate.net/publication/309439742_Climate_pCO2_and_terrestrial_carbon_cycle_linkages_during_late_Palaeozoic_glacial-interglacial_cycles[3] Montañez, I. P. et al. CO2-forced climate instability and linkages to tropical vegetation during late paleozoic deglaciation. Science 315, 87–91 (2007).
https://www.researchgate.net/publication/261180132_CO2-Forced_Climate_and_Vegetation_Instability_During_Late_Paleozoic_Deglaciation[4] Breecker, D. O. Quantifying and understanding the uncertainty of atmospheric CO2 concentrations determined from calcic paleosols. Geochem. Geophys. Geosyst. 14, 3210–3220 (2013).
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/ggge.20189[5] Georg Feulner. Coal formation and global glaciation. Proceedings of the National Academy of Sciences Oct 2017, 114 (43) 11333-11337; DOI: 10.1073/pnas.1712062114
https://www.pnas.org/content/114/43/11333
[6] Von Caemmerer, S., Quick, W. P., & Furbank, R. T. (2012). The Development of C4 Rice: Current Progress and Future Challenges. Science, 336(6089), 1671–1672. doi:10.1126/science.1220177
[7] Li, Y., Xu, J., Haq, N. U., Zhang, H., & Zhu, X.-G. (2014). Was low CO2 a driving force of C4 evolution: Arabidopsis responses to long-term low CO2 stress. Journal of Experimental Botany, 65(13), 3657–3667. doi:10.1093/jxb/eru193
[8] Dippery, J. K., Tissue, D. T., Thomas, R. B., & Strain, B. R. (1995). Effects of low and elevated CO2 on C3 and C4 annuals. Oecologia, 101(1), 13–20. doi:10.1007/bf00328894
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