34 Comments

Thanks for this issue, Isaac and Ari. I think I have been in the camp of people who acknowledge the science of global warming, but believed a) the human-driven elements of it are overstated, b) the 'worst-case' scenarios produced by unreliable models have been the foundation of advocates for climate change policy, and c) the policies that have been advocated for are mostly symbolic and do not have a reasonable benefit-cost ratio even if there is a problem and the policies would have benefits.

While I still stand by some of these points, I realize they have allowed me to be apathetic about climate change and dismissive of attempts to combat climate change. As is often the case in Tangle, this issue helped peel away some of that apathy and has created space for me to think critically about what we can and should be doing.

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That's amazing to hear. Thank you for your reply, Andrew! Bear in mind the scale of this process when evaluating it, and that the real costs of our actions are ones we haven't had to pay yet.

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Great article! You hit the high points pretty well. I am in the we need to get off our butts and make significant changes camp. Read Michael Mann’s ‘The New Climate War’. It’s eye opening.

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I finally have at least a simplistic understanding of global warming. Thank you!

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Very good article, but it misses a couple of points. Understandable.

First, we know the excess CO2 in atmosphere is due principally to our fossil fuel emissions because of the isotopic chemistry of the Carbon and the Oxygen in these extra molecules. They have the signatures of Carbon which has been buried for a long time, as well as Carbon which is produced in plants. Similarly the Oxygen. There is no source of CO2, e.g., not volcanic, which can match both of these signatures.

Second, while the equivalent CO2 of chlorofluorocarbons and CH4 are higher than unity, it is misleading to put focus there. (See the article by Professor Ray Pierrehumbert on "Short-lived climate pollution".) The culprit, dead simple, is Carbon Dioxide. Another culprit, but not a prime mover, so-to-speak, is water vapor, because an incrementally higher atmosphere carries more water vapor and water vapor is a powerful greenhouse gas. Conceptually, CO2 increases warming one unit, and water vapor adds another equivalent unit. As Professor Archer has described in a few papers, the atmospheric lifetime of CO2 is thousands of years. That's also something I think people do not understand. They think pollution from CO2 is like DDT: It'll just wash out after a while. That leads to another point.

Third, because CO2 lifetimes are so long, this means that even if all emissions are completely stopped, CO2 will linger for a long time, continuing to warm Earth. Half of the excess CO2 in atmosphere will be around for a few hundred years, but the rest of the excess CO2 will be there for thousands of years. This is important, because our horizon is limited to 2100 by the IPCC outlook, and that's a policy choice. I think it's important to realize the consequences of our choices beyond 2100. For example, all the focus is on +2C over pre-industrial now. It's a serious question whether or not we'll limit things to that. Current CO2 concentrations are 419 ppmv. As we continue to emit, it's completely reasonable that we'll get to 600 ppmv. Well, facts are, in the Pliocene, the last time atmospheric CO2 was in excess of 400 ppmv, evidence suggests climate not only had no Arctic ice cap, the mean global temperature was +15C over our pre-industrial. But that's an EQUILIBRATED climate, something it takes hundreds of years to get. So, if we somehow magically manage to keep atmospheric concentrations to 450 ppmv but no higher, we might keep global mean temperature to +2C or +2.5C in 2100, but warming's not going to stop there. It will continue, and in 200 or 300 years it could be +10C or more. This is the basis for the emphasis upon the notion that once we zero emissions -- and I really mean ZERO emissions -- we need to figure out a reliable means of getting CO2 concentrations in atmosphere lower, preferable to below 350 ppmv. That is an incredibly difficult task. It's even much harder than ZEROING emissions.

Fourth, if in fact, this is an urgent matter, and especially if the word "emergency" is justified, it needs to be treated as such. Obvious, entrenched interests are going to oppose this, but the biggest thing I find disheartening is that what I can only suppose are well-meaning concerns expressed as opposition by environmental groups to siting of solar and wind energy systems -- and battery storage facilities -- is today, in the United States (at least) as much an impediment to rapid progress on transitioning off fossil fuels. Warming from excess concentrations of CO2 are harming ecosystems and forests and oceans right now, and if we don't rapidly do something about that, that will clobber any benefits that might be had from incrementally saving an ecosystem here, a habitat there, and a species over there. The environmental movement really needs to do some soul searching here, and examine the Nature-as-static or Nature-as-good-and-God-given assumptions their attitudes and policies are based upon. I recommend Botkin's DISCORDANT HARMONIES, 1990, which isn't perfect, but it goes in the right direction here.

Fifth ... environmental and climate justice ... Yes, these are very important and should be addressed. However, to the point of packaging the solving of social ills with solving climate, I paraphrase the speech of Van Jones at the FORWARD ON THE CLIMATE RALLY from 2013. Rev Jones was addressing President Obama with respect to Keystone XL, which thankfully has FINALLY been put down. But what he said applies to the bigger context: "All the good you've done, all the good you can imagine doing, will be wiped out ... wiped out, by fires, by floods, by superstorms ...." Trade-offs and triage are necessary. Quantitative balance is necessary.

Sixth, while humanity has devastated ecosystems, these have responded. If something were to happen to humanity in the next 100 years causing it to disappear, extraterrestrials visiting 1000 years from now might not notice the devastation we wreaked on the biosphere. But they definitely WOULD notice our legacy in the form of unnaturally caused excessive Carbon Dioxide. In fact, such a signature will eventually be visible to sufficiently sensitive extraterrestrial spectroscopic instruments, far away. I think that's a heck of a thing, that ultimately, if we were to disappear, our legacy and purpose written on Earth is our Carbon Worshipping habit, and our excess CO2.

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The solution is easy and requires only the will and not much money or time. Our energy consumption has to change from burning fossil fuels to sustainable electric power. When electricity is much cheaper than fossil fuels, every industry that requires energy will convert rapidly or die out.

1. Immediately convert coal generated energy to Natgas

2. Meanwhile build nuclear power plants everywhere

3. Use nuclear power for ships, trains and electric for trucks, buses, cars and subways.

4. Set CO2 emission limits like we did for smog so that the car makers fleets have to move to electric and industry would move to electricity as well.

5. Enforce pollution laws like dumping wastes in rivers (won't solve CO2 but let's do it anyway.)

Cheap electricity will move energy consumption from fossil fuels very quickly but carbon levies would speed it up in wealthy countries.

Rich countries must build the nuclear facilities in poor countries so they can get the benefit of cheap power without the need to get hooked on fossil fuels. This would make them more productive, wealthier and consumers. This money could come from not giving the wealthy incentives on their Teslas, and removing tax breaks for solar panels and windmill which are inefficient at producing energy and use more resources than they save. We could also get the tens of thousand of climate scientists doing something more valuable and off the government teat.

Of course the whole green energy activism industry would be reduced and in and uproar, but they will find something quickly, no doubt.

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There is a lot of psychological data on why humans ignore things that are seemingly "inconvenient" be they the climate, health, race relations, financial, etc. These things are not pleasant to deal with, require a lot of work within a system that does not deliver a lot of promise for significant progress, etc. Humans seek comfort, and the more comfortable one is, I think generally the less tolerant of discomfort one becomes. Pair that with how most people don't see the effects of climate change effecting them personally on a day to day basis. That HAS been changing as we see more 100 year events (storms, etc.) happening on an annual basis, so as these effects do manifest, I do think we are seeing polls shift at least in terms of people recognizing that climate change is real. That may not be enough to convince many that we are causing it or that we can prevent it, but at least it's a start and it makes it more likely that people will at least want to do something proactive, whether they think we've caused it or not. Gen-Z also seems to be fully bought into this, and Millenials are not far behind, so given time (something I know we presumably don't have a whole lot of), the overall opinion will shift. It already has quite a bit, but it will continue to. That's my semi-hopeful thought around this topic.

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The science on climate change is established, there is an overwhelming, worldwide consensus on the causes and effects of CO2 emissions produced by burning fossil fuels. As it turns out there is also a consensus on the next good step in addressing climate change. This consensus comes from economists, who universally agree, that a price on carbon is the necessary (but not sufficient) next step to take in addressing this problem. The Climate Leadership Council published a statement supporting carbon pricing in the Wall Street Journal in January of 2019 that was signed by 28 Nobel Laureate Economists, 4 Former Chairs of the Federal Reserve, 15 Chairs of the Council of Economic Advisers and at this time has been signed by over 3000 economists from across the country. I am a volunteer which Citizens Climate Lobby, a grassroots, non-partisan organization focused on building political consensus for national legislation for a carbon fee and dividend (returned to citizens) with a border carbon adjustment fee. Carbon pricing would be a good subject for a future article!

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What can individuals do? STOP USING FOSSIL FUELS! Go solar, buy an EV, switch to biofuel, avoid plastic packaging, join your local climate group, vote for candidates that promise to take action on climate legislation, be like Greta: believe the scientists! TAKE ACTION YOURSELVES!

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Coincidentally and ironically Coleman Hughes latest podcast posted the same day is an interview with Michael Shellenberger. I’m curious why your and Ari’s commentary made no reference to his POV which is equally based on data. This is worth listening to for an alternative perspective. https://podcasts.apple.com/us/podcast/conversations-with-coleman/id1489326460?i=1000525199708

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I am sympathetic to the ecomodernist perspective, which Shellenberger apparently is as well. However, his writings suggest he is incredibly narrow minded regarding how the biosphere of the planet works, or what the long term consequences of continued planetary scale emissions of CO2 are. I agree, as I've noted elsewhere here, many environmentalists of today are not helping, and indeed are stuck in a mindset where they think, basically, Nature will take care of itself if it is left alone. That isn't correct at all, and intervention in natural systems is essential. Still, a lot of the proposals Mr Shellenberger has are outrageously expensive, too slow, and might be okay for an elite on the planet, but not the rest of its people. I'd say, too, that Mr Shellenberger's approach, if adopted, would guarantee the need to pursue a program of "albedo hacking" of Earth, which is sometimes overgenerously referred to as "solar geoengineering". That's madness. I don't know if Mr Shellenberger has ever admitted that.

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Your last paragraph says it all, Isaac. You think our backs are against the wall. I don't. As with any issue this complex, a good case can be made for either viewpoint. Contrary to your usual practice, Isaac, here you make a case for only one viewpoint. And not, IMO, a very good case.

Your chart, "Estimated Global Temperature Over the Last 500 Million Years" also says it all. For most of that time, and notably recently, earth was much warmer than it is today. Two short paragraphs above that, your chart, "Atmospheric CO2 Concentration" goes back only 0.8 million years, less than 0.2% as far. Naturally you get the hockey stick effect. For most of earth's history, CO2 concentration was much higher than it is today, but you don't show that 99.8% of the data.

Your Keeling Curve" does not, as you say, "demonstrate[s] the increase of atmospheric concentration of carbon over time." It goes back a mere 60 years. Earth is 4.5 billion (with a B) years old. There was a lot more atmospheric CO2 than now in the not so distant past, and even more CH4.

Do you know the parable of the blind men and the elephant? When it comes to climate change, alarmists and deniers are perhaps equally blind. Even so, it is a mistake to listen only to one. You could, and should, have presented both sides.

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Hi Shawn, sorry that I am not Isaac, but as a co-author of this piece I am going to take the liberty to respond to your criticisms.

The charts provided can only go back as far as the data for them exist. The Mauna Loa data has only been gathered since 1958. Likewise, ice core data can only be provided for as far back as Earth has had ice sheets. The deficiencies in these data sets were addressed in the discussion on temperature over geological time, where we acknowledge that the Earth has been far hotter in the past and scientists agree that there was more carbon in the atmosphere at those times.

And as a quick note, the Keeling data does demonstrate the increase of atmospheric carbon concentration over time. It is an incomplete sample of Earth's history, as you noted, but it does do that.

I also want to clarify some stances we're staking out here. The Earth getting hotter will not cause the destruction of the planet. The atmosphere containing more carbon than it did 100 years ago will not cause the destruction of the planet. The article addressed these points in the "Skepticism" portion, and I agree that language like "we are destroying our planet" and "we are all going to die" is exaggerated and counter-productive.

The whole staff took pains to be specific with our language on this piece, and the effects of climate change that we're illustrating are a loss of habitable land, biodiversity, and the general stability of ecosystems we have relied on for a livable climate for Earth's billions of human inhabitants. We do not claim that the entire livable climate will be destroyed, but that a large portion will and that the effects of such rapidly increased warming are not known, which is also concerning.

"Backs against the wall" is a colloquialism that you can disagree with because it isn't clearly defined, but it was meant as "at a point where if we do not take significant action soon, human intervention will no longer be effective." Even in that sentence, the word "soon" isn't well defined and there is certainly a lot of valid debate about what that means, and what "significant action" entails.

As far as the existence of anthropogenic climate change and its predicted effects, this article stays within the bounds of scientific consensus. As Isaac said in the introduction, this is an edition that (like many Friday editions) doesn't exist within the framework of dialectic political viewpoints, but instead presents the science behind an issue of global importance, which in and of itself does not exist within a framework of multiple valid understandings.

Specifics and interpretations can be challenged, and Isaac and I are happy to respond to those, but there aren't two valid sides to whether or not humans are causing climate change.

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Thanks, Ari - I think this is a good summary of how I would have responded myself. I'd only add a bold print here that I find the mistakes of *other* news outlets are often projected onto Tangle. A careful read of this edition, in my opinion, shows that we're focusing cleanly on the science of what is and what is not — and how we know that. Shawn, I do think the criticisms here you point out are fair, my contention would be the same as Ari's, though: they're all addressed directly in the piece!

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Thank you, Ari, for a thoughtful comment. Thank you, Isaac, for the same. Are either of you going to admit that I sent you, three weeks ago, a very similar article by me that reached a somewhat different conclusion? I can see some of my points in Ari's piece, which he wrote after seeing mine.

Aside from that slight, the whole point I want to make is that climate change is complicated, and like other complex issues, it can be twisted to advance various agendas. As it has been. It is not about the planet. It is about the agendas.

For anyone other than Isaac and Ari who sees this, If you want to read My Take, shoot an email to Shawn.Spilman@gmail.com. (Just one L, please.)

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The Earth also at one time contained much more Oxygen in its atmosphere, and modern humans would not have survived in that atmosphere five minutes.

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Yes, Jan, "The Great Oxygenation Event." (Wikipedia's article on that is fascinating for it's diversity of opinion, something lacking here on this one particular day.) But it is hard to keep O2 in an atmosphere because O2 reacts strongly with almost everything. Back then, it reacted with the much-higher-than-now levels of methane, also produced by bacteria back when bacteria and algae were all the life there was on earth. A Scientific American article on this subject from 8-19-09 concludes with the line, ". . . the origins of oxygen in Earth's atmosphere derive from one thing: life." All of the O2 in our air was created by living organisms, nowadays mostly plants that also take out the carbon we put there.

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Yes, but just because some life, even most life creates and enjoys such an environment, and even fixes the excess, does not mean that Sweaty Hominids (us) would do well there, if survive at all. Accordingly, citing historical conditions of atmosphere and oceans and inferring that it'll be okay in the future if conditions return there is silly. Those ages were a different Earth, one quite hostile to us. As far as we're concerned it might as well have been the Moon.

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Some smart people believe that we could survive and thrive on Mars, right now, if we could only get there.

Are you saying that because things are fine right now, we should interfere with natural processes that have been going on for nearly five billion years to keep them just this way? I am OK with that. I like earth how it is right now. I just think it is a lot to strive for and far more than we are capable of. I worry that we would f**k it up.

Jan, I am NOT arguing with you. I agree with you. I am just explaining what your insights make me think about.

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The idea that "natural processes" existing for "five billion years" does not mean they were some kind of happy equilibrium before we showed up. Life almost went extinct, at least once.

"I like Earth how it is right now" means (a) y'need to study about lags, (b) y'really don't know how it works now, and (c) y'haven't really looked into the effects we're having upon it, including those signaled by the phenology of the biosphere.

And we are f**king it up, right now, with our outrageous greenhouse gas emissions, especially CO2.

Do you seriously think our portfolio evidenced by the mess we've made of Earth warrants any kind of an attempt to colonize Mars? Visit and explore, yes. Live, no.

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If your data goes back only as far as there were glacial ice sheets, naturally you miss the majority of the warm times when there were no ice sheets. And if you think the only valid side is that humans are causing climate change, how do you account for all the climate change that occurred before we were around? As for the bounds of "scientific consensus," go sit with Anthony Fauci.

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These points seem to be addressed already in the article, which explicitly discusses the limits of the existing data and repeatedly acknowledges that climate change is a natural phenomenon. I do not think anyone seriously engaging in this subject is making the argument that before humans the climate was steady and unchanging, so arguing against that position is a straw man.

Just because the earth has been warmer before does not mean we would thrive or even survive in that environment, or perhaps more importantly, in the transition. It is not just the change, but the speed of the change, which matters for things like ecosystem adaptation. You might be perfectly comfortable in a t-shirt, but if there is no fish in the ocean and no wheat on the land, it's going to be a bad time. Not to be glib, but the earth has also had six mass extinctions, and as natural as those events are, it would probably be best not to be in one.

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"Just because the earth has been warmer before does not mean we would thrive or even survive in that environment, or perhaps more importantly, in the transition." And yet, Tom, we humans have lived and evolved over the last six million years when earth was warmer, often much warmer; and our ancestors thrived over all other vertebrates during all the climate transitions of the past 500 million years since the earliest vertebrates.

Consider the wide range of climates where people live today, from the Inuit of Nunavut to the Amazon tribes. Even so, we humans are essentially tropical animals, poorly adapted to cold and able to survive it only with elaborate clothing and shelter. We might actually continue to thrive, were the planet a little warmer, just as we did back when it once was. It is why folks move to Florida.

I do not disagree with you. In fact, I think you make the stronger case. I merely wish to present the other side that is absent from this uncharacteristically biased article.

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First, as always, thanks for the effort, talent and philosophy that make Tangle my preferred morning read. Now onto the issue at hand.

Is there a bigger more existential question that your essay has not addressed? What’s more important, saving a species or saving the planet?

Given that of all the species that have existed on earth, 99.9% are now extinct (https://www.pbs.org/wgbh/evolution/extinction/massext/statement_03.html), and those that have survived are all simple single cell type organisms, why do we address this problem from the principle of the exceptionalism of Homo sapiens?

There is a simple answer that puts the planet first, yet still allows for evolutionary principles to maintain our genus if not our species. It would be to hasten the transition to a post-Sapiens society dominated by intelligent machines. These machines will be beyond bio-chemical dependancy creating energy from the sun with minimal impact on the planet. No need to eat, stay warm, travel, propagate etc. This would also solve some other acute issues as ‘Homo Intelligus’ would see no skin color and have no need of gender or sex. They’d probably be non-partisan in political terms too! That would be a result!

Would welcome your thoughts.

PS. If this thesis is too abstract, then I do have some more pragmatic and tangible observations in this short essay I wrote 18 months ago:

https://www.insearchofsanity.org/blogs/the-nuclear-size-holes-in-the-climate-change-argument

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Clive, I quite enjoyed your essay. I would add one other point though. Immigration is a huge negative for the GREEN movement. Though I am not anti-immigration, when people from very poor countries, using very little fossil fuels or consuming productw made from them, migrate to richer countries such as the US, Canada or Euro countries, their carbon footprint expands mightily. One could say if you are green the you have to be anti-immigration :).

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Thanks Dan, I agree with you on immigration. The irony is that there is an inherent hypocrisy in the position of many of the climate change activists. They want to pull up the drawbridge on all the ‘progress’ made by Homo Sapiens as a result of learning to harness the power of carbon. That will inevitably have a negative impact on the majority of the species that has yet to enjoy the associated rise in living standards, and yet the same activists are the often the ones who lament the challenges facing the 5bn people who live in the ‘developing’ world outside of Europe and The West.

Furthermore, the acolytes of Greta are the same people who rely on the internet and digital technologies which are huge consumers of energy. The same ones who insist on being driven to school or taking foreign holidays. Who want all the mod cons to play with and who must buy the newest and trendiest consumer goods.

I’m interested that so far no one has addressed my thesis that if the species is serious about ‘saving the planet’ from human caused global warming, the obvious answer is to hasten the demise of humans.

Intelligent machines will be far more environmentally friendly! And more woke!

A win win?

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