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The global CO2 rise: the facts, Exxon and the favorite denial tricks

Filed under: — stefan @ 25 January 2018

The basic facts about the global increase of CO2 in our atmosphere are clear and established beyond reasonable doubt. Nevertheless, I’ve recently seen some of the old myths peddled by “climate skeptics” pop up again. Are the forests responsible for the CO2 increase? Or volcanoes? Or perhaps the oceans?

Let’s start with a brief overview of the most important data and facts about the increase in the carbon dioxide concentration in the atmosphere:

  1. Since the beginning of industrialization, the CO2 concentration has risen from 280 ppm (the value of the previous millennia of the Holocene) to now 405 ppm.
  2. This increase by 45 percent (or 125 ppm) is completely caused by humans.
  3. The CO2 concentration is thus now already higher than it has been for several million years.
  4. The additional 125 ppm CO2 have a heating effect of 2 watts per square meter of earth surface, due to the well-known greenhouse effect – enough to raise the global temperature by around 1°C until the present.

Fig. 1 Perhaps the most important scientific measurement series of the 20th century: the CO2 concentration of the atmosphere, measured on Mauna Loa in Hawaii. Other stations of the global CO2 measurement network show almost exactly the same; the most important regional variation is the greatly subdued seasonal cycle at stations in the southern hemisphere. This seasonal variation is mainly due to the “inhaling and exhaling” of the forests over the year on the land masses of the northern hemisphere. Source (updated daily): Scripps Institution of Oceanography.

Fig. 2 The CO2 concentration of the atmosphere during the Holocene, measured in the ice cores from Antarctica until 1958, afterwards Mauna Loa. Source: Scripps Institution of Oceanography.

These facts are well known and easy to understand. Nevertheless, I am frequently confronted with attempts to play down the dangerous CO2-increase, e.g. recently in the right-leaning German newspaper Die Welt.

Are the forests to blame?

Die Welt presented a common number-trick by climate deniers (readers can probably point to some english-language examples):

In fact, carbon dioxide, which is blamed for climate warming, has only a volume share of 0.04 percent in the atmosphere. And of these 0.04 percent CO2, 95 percent come from natural sources, such as volcanoes or decomposition processes in nature. The human CO2 content in the air is thus only 0.0016 percent.

The claim “95 percent from natural sources” and the “0.0016 percent” are simply wrong (neither does the arithmetic add up – how would 5% of 0.04 be 0.0016?). These (and similar – sometimes you read 97% from natural sources) numbers have been making the rounds in climate denier circles for many years (and have repeatedly been rebutted by scientists). They present a simple mix-up of turnover and profit, in economic terms. The land ecosystems have, of course, a high turnover of carbon, but (unlike humans) do not add any net CO2 to the atmosphere. Any biomass which decomposes must first have grown – the CO2 released during rotting was first taken from the atmosphere by photosynthesis. This is a cycle. Hey, perhaps that’s why it’s called the carbon cycle!

That is why one way to reduce emissions is the use of bioenergy, such as heating with wood (at least when it’s done in a sustainable manner – many mistakes can be made with bioenergy). Forests only increase the amount of CO2 in the air when they are felled, burnt or die. This is immediately understood by looking at a schematic of the carbon cycle, Fig. 3.

Fig. 3 Scheme of the global carbon cycle. Values ​​for the carbon stocks are given in Gt C (ie, billions of tonnes of carbon) (bold numbers). Values ​​for average carbon fluxes are given in Gt C per year (normal numbers). Source: WBGU 2006 . (A similar graph can also be found at Wikipedia.) Since this graph was prepared, anthropogenic emissions and the atmospheric CO2 content have increased further, see Figs 4 and 5, but I like the simplicity of this graph.

If one takes as the total emissions a “natural” part (60 GtC from soils + 60 GtC from land plants) and the 7 GtC fossil emissions as anthropogenic part, the anthropogenic portion is about 5% (7 of 127 billion tons of carbon) as cited in the Welt article. This percentage is highly misleading, however, since it ignores that the land biosphere does not only release 120 GtC but also absorbs 122 GtC by photosynthesis, which means that net 2 GtC is removed from the atmosphere. Likewise, the ocean removes around 2 GtC. To make any sense, the net emissions by humans have to be compared with the net uptake by oceans and forests and atmosphere, not with the turnover rate of a cycle, which is an irrelevant comparison. And not just irrelevant – it becomes plain wrong when that 5% number is then misunderstood as the human contribution to the atmospheric CO2 concentration.

The natural earth system thus is by no means a source of CO2 for the atmosphere, but it is a sink! Of the 7 GtC, which we blow into the atmosphere every year, only 3 remain there. 2 are absorbed by the ocean and 2 by the forests. This means that in the atmosphere and in the land biosphere and in the ocean the amount of stored carbon is increasing. And the source of all this additional carbon is the fact that we extract loads of fossil carbon from the earth’s crust and add it to the system. That’s already clear from the fact that we add twice as much to the atmosphere as is needed to explain the full increase there – that makes it obvious that the natural Earth system cannot possibly be adding more CO2 but rather is continually removing about half of our CO2 emissions from the atmosphere.

The system was almost exactly in equilibrium before humans intervened. That is why the CO2 concentration in the air was almost constant for several thousand years (Figure 2). This means that the land ecosystems took up 120 GtC and returned 120 GtC (the exact numbers don’t matter here, what matters is that they are the same). The increased uptake of CO2 by forests and oceans of about 2 GtC per year each is already a result of the human emissions, which has added enormous amounts of CO2 to the system. The ocean has started to take up net CO2 from the atmosphere through gas exchange at the sea surface: because the CO2 concentration in the atmosphere is now higher than in the surface ocean, there is net flux of CO2 into the sea. And because trees take up CO2 by photosynthesis and can do this more easily if you offer them more CO2 in the air, they have started to photosynthesize more and thus take up a bit more CO2 than is released by decomposing old biomass. (To what extent and for how long the land biosphere will remain a carbon sink is open to debate, however: this will depend on the extent to which the global ecosystems come under stress by global warming, e.g. by increasing drought and wildfires.)

The next diagram shows (with more up-to-date and accurate numbers) the net fluxes of CO2 (this time in CO2 units, not carbon units!).

Fig. 4 CO2 budget for 2007-2016, showing the various net sources and sinks. The figures here are expressed in gigatons of CO2 and not in gigatons of carbon as in Fig. 3. The conversion factor is 44/12 (molecular weight of CO2 divided by atomic weight of carbon). Source: Global Carbon Project.

Fig. 5 shows where the CO2 comes from (in the upper half you see the sources – fossil carbon and deforestation) and where it ends up (in the lower half you sees the sinks), in the course of time. It ends up in comparably large parts in air, oceans and forests. The share absorbed by the land ecosystems varies greatly from year to year, depending on whether there were widespread droughts, for example, or whether it was a good growth year for the forests. That is why the annual CO2 increase in the atmosphere also varies greatly each year, and this short-term variation is not mainly caused by variations in our emissions (so a record CO2 increase in the atmosphere in an El Niño year does not mean that human emissions have surged in that year).

Fig. 5 Annual emissions of carbon from fossil sources and deforestation, and annual emissions from the biosphere, atmosphere and ocean (the latter are negative, meaning net uptake). This is again in carbon (not CO2) units; the 12 gigatons of carbon emitted in 2016 are a lot more than the 7 gigatons in the older Fig. 3. Source: Global Carbon Project.

The “climate skeptics” blaming the forests for most of the increase in atmospheric CO2, because of decaying foliage and deadwood, is not merely wrong, it is pretty bonkers. Have leaves started to decompose only since industrialization? Media with a minimum aspiration to credibility should clearly reject such nonsense, instead of spreading it further. In case of Die Welt, one of my PIK colleagues had explicitly pointed out to the author, in response to a query by him, that the 5% human share of CO2 is misleading and that humans have caused a 45% increase. That the complete CO2 increase is anthropogenic has been known for decades. The first IPCC report, published in 1990, put it thus:

Since the industrial revolution the combustion of fossil fuels and deforestation have led to an increase of 26% in carbon dioxide concentration in the atmosphere.

In the 27 years since then, the CO2 increase caused by our emissions has gone up from 26% to 45%.

How Exxon misled the public against better knowledge

One fascinating question is where this false idea of humans just contributing a tiny bit to the relentless rise in atmospheric CO2 has come from? Have a look at this advertorial (a paid-for editorial) by ExxonMobil in the New York Times from 1997:

Fig. 6 Excerpt from the New York Times of 6 November 1997

The text to go with it read:

While most of the CO2 emitted by far is the result of natural phenomena – namely respiration and decomposition, most attention has centered on the three to four percent related to human activities – burning of fossil fuels, deforestation.

That is pretty clever and could hardly be an accident. The impression is given that human emissions are not a big deal and only responsible for a small percentage of the CO2 increase in the atmosphere – but without explicitly saying that. In my view the authors of this piece knew that this idea is plain wrong, so they did not say it but preferred to insinuate it. A recent publication by Geoffrey Supran and Naomi Oreskes in Environmental Research Letters has systematically assessed ExxonMobil’s climate change communications during 1977–2014 and found:

We conclude that ExxonMobil contributed to advancing climate science—by way of its scientists’ academic publications—but promoted doubt about it in advertorials. Given this discrepancy, we conclude that ExxonMobil misled the public.

They explain their main findings in this short video clip.

Does the CO2 come from volcanoes?

Another age-old climatic skeptic myth, is that the CO2 is coming from volcanoes – first time I had to rebut this was as a young postdoc in the 1990s. The total volcanic emissions are between 0.04 and 0.07 gigatonnes of CO2 per year, compared to the anthropogenic emissions of 12 gigatons in 2016. Anthropogenic emissions are now well over a hundred times greater than volcanic ones. The volcanic emissions are important for the long-term CO2 changes over millions of years, but not over a few centuries.

Does the CO2 come from the ocean?

As already mentioned and shown in Figs. 4 and 5, the oceans absorb net CO2 and do not release any. The resulting increase in CO2 in the upper ocean is documented and mapped in detail by countless ship surveys and known up to a residual uncertainty of + – 20% . This is, in itself, a very serious problem because it leads to the acidification of the oceans, since CO2 forms carbonic acid in water. The observed CO2 increase in the world ocean disproves another popular #fakenews piece of the “climate skeptics”: namely that the CO2 increase in the atmosphere might have been caused by the outgassing of CO2 from the ocean as a result of the warming. No serious scientist believes this.

Remember also from Figs. 4 and 5 that we emit about twice as much CO2 as is needed to explain the complete rise in the atmosphere. In case you have not connected the dots: the denier myth of the oceans as cause of the atmospheric CO2 rise most often comes in the form of “the CO2 rise lagged behind temperature rise in glacial cycles”. It is true that during ice ages the oceans took up more CO2 and that is why there was less in the atmosphere, and during the warming at the end of glacial cycles that CO2 came back out of the ocean, and this was an important amplifying feedback. But it is a fallacy to conclude that the same natural phenomenon is happening again now. As I explained above: measurements clearly prove that the modern CO2 rise has a different cause, namely our fossil fuel use. What is the same now and over past glacial cycles is not the CO2 source, but the greenhouse effect of the atmospheric CO2 changes:  without that we could not understand (or correctly simulate in our climate models) the full extent of glacial cycles.

The cyanide cocktail

A man offers you a cocktail with a little bit of cyanide at a party. You reject that indignantly, but the man assures you it is completely safe: after all, the amount of cyanide in your body  after this drink would be only 0.001 percent! This could hardly be harmful! Those scientists who claim that 3 mg cyanide per kg of body weight (ie 0.0003 percent) are fatal are obviously not to be trusted. Are you falling for that argument?

We hope not, and we hope you will neither fall for the claim that 0.0125 percent of CO2 (that’s the 125 ppm increase caused by humans) can’t be bad because that number is small. Of course, the amount of CO2 in the air could also be expressed in kilograms: it is 3200 billion tons or 3,200,000,000,000,000 kilograms. Of this humans are responsible for almost 1000 billion tons. (Does that sound more harmful than 0.0125 percent?) Since the year 1870, we have even emitted a total of about 2,000 billion tons. As already explained, forests and oceans have removed about half of that from the atmosphere.

Scientists specify the concentration of individual gases in the atmosphere as volume fractions (rather than, e.g., grams per cubic meter of air) because then the numbers do not depend on temperature and pressure, which vary greatly in the atmosphere. As far as climatic impact is concerned, however, the fraction of the total mass of the atmosphere is irrelevant since the atmosphere consists of 99.9% nitrogen, oxygen and argon, i.e. gases which cannot absorb infrared radiation. Only molecules made of at least three atoms absorb heat radiation and thus only such trace gases makes the greenhouse effect, and among these CO2 is the second most important after water vapor. All this has been known since John Tyndall’s measurements of the greenhouse effect of various gases in 1859. Tyndall back then wrote:

[T]he atmosphere admits of the entrance of the solar heat, but checks its exit; and the result is a tendency to accumulate heat at the surface of the planet.

That is still a great concise description of the greenhouse effect! Without CO2 in the air our planet would be completely frozen, no life would be possible. With CO2, we are turning one of the major control knobs of global climate.

The climate effect

So let’s finally come to the climatic effect of the CO2 increase. As for cyanide, the effect is what counts, and not whether compared to some large mass the fraction is 10 percent or 0.01 percent. The dose effect of toxins on humans can be determined from experience with victims. The climatic impact of greenhouse gases can either be calculated on the basis of an understanding of the physical processes, or it can be determined from the experience of climate history (see my previous post). Both come to the same conclusion. The climate sensitivity (global warming in equilibrium after CO2 doubling) is around 3°C, and the expected warming to date, due to the current CO2 increase, is around 1°C. This corresponds quite exactly to the observed global warming (Fig. 7). For which, by the way, there is no natural explanation, and the best estimate for the anthropogenic share of global warming since 1950 is 110 percent – more on this in my previous post.

Fig. 7 Time evolution of global temperature, CO2 concentration and solar activity. Temperature and CO2 are scaled relative to each other as the physically expected CO2 effect on the climate predicts (i.e. best estimate of the climate sensitivity). The amplitude of the solar curve is scaled as derived from the observed correlation of solar and temperature data. (Details are explained here ). This graph can be created here and you can copy a code that can be used as a widget in any website (as in my home page), where it is automatically updated every year with the latest data. Thanks to Bernd Herd who programmed this.

Finally, here is a slick new video clip illustrating the history of CO2 emissions on the map:

Links

Physics Today: The carbon cycle in a changing climate

240 Responses to “The global CO2 rise: the facts, Exxon and the favorite denial tricks”

  1. 151
    Ray Ladbury says:

    Peter Carson, I can’t figure out whether you are lying your pasty white ass off or merely deluded.

    The climates on Earth, Mars and Venus are well explained by the consensus theory of planetary climates. Anthropogenic carbon emissions are merely one aspect of this theory as it pertains to Earth.

    As to heat from Earth’s interior, sorry, try again. It doesn’t come close to causing the warming seen.

  2. 152
    Eli Rabett says:

    R3 147 Peter Carson:

    There are several reasons why your answer is a nonsense.

    1. Overtones are very weak (theory) and not seen in emission spectra of the earth measured from space or in atmospheric observations (observation). If they were a significant way to export energy they would be observed. Pls provide an example if you dispute this

    The rest is pretty much TL:DR

    2. N2 and O2 vibrational transitions period are forbidden by symmetry for electric dipole transitions. Allowed quadrupole and magnetic dipole transitions are allowed but are vanishingly weak, let alone the overtones thereof. They can (barely) be seen in absorption through the entire thickness of the atmosphere but not in emission

    3. Overtones for H2O and CO2 are allowed for electric dipole transitions because of small anharmonicities in the vibrational potential energy but are as it says, really weak.

    4. Overtones in H2O and CO2 are high frequency short wavelength (theory and experiment) and shifted out to the tail of the 200-300 K black body spectrum where there is little intensity (addition)

    5. Emission from overtone would require population of high lying vibrational states (theory). While emission from these states is observed, they are all fundamental transitions to lower lying, but vibrationally excited states and much weaker than those observed from the fundamental transitions to the ground vibrational state e.g. 2 to 1 vs 1 to 0 the overtone would be 2 to 0

  3. 153
    nigelj says:

    Peter Carson @147 thinks global warming is caused by diverging techtonic plate boundaries. He has also claimed el nino is caused by undersea volcanoes (yikes)

    He provides no proper calculations on how much heat this sort of activity would let escape into the oceans. The peer reviewed studies and comment from experts in the link posted by Phil Scadden above show heat released form the earths interior is quite small compared to other sources of heat.

    There’s no evidence that techtonic plate activity has changed substantially since 1980, the modern global warming period.

    A quick look at volcanic activity shows little difference overall between the 19th and 20th centuries. Wikipedia has articles on this.

    Peters theories have no merit.

    Peter, the basic idea is worth considering, but you have to do the hard numerical science and show the numbers and evidence, with field research or an internet link to research done by others. Otherwise you are flying a kite / speculating.

  4. 154
    Jim Eager says:

    Folks, Peter Carson is a fringe crank and Galileo wanna be.
    An educated crank, but a crank none the less.

    Feed at your own risk.

  5. 155
    Mal Adapted says:

    Peter Carson:

    My detailed & usually quantitative answers are at my site – but you folk seem to have an aversion to even looking at non-AGW.

    I have an aversion to wasting my time on non-peer-reviewed “scientific” arguments, especially by those who haven’t put the time in to understand the relevant principles, nor participated in the modern culture and practice of the Earth Sciences, to say nothing of ignoring the multiple lines of evidence for AGW.

    Do you think it’s respectable to rebunk undead AGW-denialist memes long since decisively debunked by working climate scientists?

  6. 156

    PC 147: Can AGW explain the GE on Venus, Earth and Mars? (Quantitative please.)

    BPL: Not AGW, but standard greenhouse theory, yes. Here it is quantitatively:

    http://saspcsus.pbworks.com/w/file/fetch/64696386/planet%20temperatures%20with%20surface%20cooling%20parameterized.pdf

  7. 157
    Phil Scadden says:

    So Peter, still not opening the textbook? And still not seeing your undersea volcano nonsense violates observations of vertical temperature profile, heat capacity, gas measurements whereas hurricanes (and cyclones worldwide) are quite adequately explained in conventional climate theory – which you seem to flatly refuse to look at.

    I imagine that you are having enormous difficulties with surface temperature on Venus using the Peter Carson Greenhouse effect. However, the real greenhouse gas model has no problem. You have to use the RTEs I pointed to in 140 (but you obviously ignored) and codes like Modtran or Hitran to calculate them. A more simplistic overview is here.

    As to my work – yes I am conflicted, but at least noone can accuse me of being on some imaginary climate-science gravy train. And as to whether the thermal models are realistic – well oil industry wouldnt use them if they werent. They get tested with the temperature profile and hydrocarbon characteristics of every well drilled.

  8. 158
    nigelj says:

    Ray Ladbury, I would say people post crazy alternative theories for all sorts of reasons. Sometimes its just delusional but well intended lateral thinking, sometimes it’s because they have forgotten to take the anti psychotic medication, sometimes they are paid to post certain stuff.

  9. 159
    Peter Carson says:

    Eli. #152 & #125.
    See my #134, ie
    “All molecules emit ENERGY*, including those that do not absorb it. Therefore, it’s only the total density at any particular height that determines how much heat in the form of IR is released, eventually to space.”
    (*I changed the first IR to ENERGY to suit your sensitivities, becoming essentially a re-statement of the 2nd Law of Thermodynamics. I’m not so interested in mechanisms as the final result, but unless your mechanism matches data, it’s wrong.)

  10. 160
    Peter Carson says:

    #156 Leveson:
    Thanks for referencing your paper – although you seem not to have bothered reading mine ie past the Commentary. It demonstrates that papers supporting AGW have easier access to being published, despite having several undermining errors and questionable assumptions.

    For example, your
    1. “However, it is nearly impossible to fit Venus, Earth and Mars at the same time without unphysical results (negative Fc) for at least one planet.”

    2. “The Intergovernmental Panel on Climate Change (IPCC, 2007, p. 9) estimates ∆T2X= 2.0–4.5K with feedbacks included, with a best estimate ≈3 K.” and
    “Hansen and Sato (2007) have suggested that long-term climate sensitivity is, in fact, about 6 K.”

    3. “For Mars to absorb a higher sunlight proportion than Earth despite 200 times less atmosphere mass seems counterintuitive, but of course Mars has extensive dust storms – and low-altitude dust heats lower layers of atmosphere and thus the surface.”

    4. “7. Results for the solar system
    Temperature figures from the model were Ts = 715.8, 288.4, and 228.0 K for Venus, Earth, and Mars. More detail is given in Table 2. Relative errors were about 2.7%, 0.1%, and 6.5% for Venus, Earth, and Mars, respectively.”
    ———————————————————
    Your 1 supports my contention that AGW cannot deal with Venus, Earth and Mars’ Greenhouse Effect.

    Your 2 shows that one needs to be “flexible” with estimates.

    Your 3 shows such flexibility.
    a. Mars’ dust storms don’t last forever. Such measurements have been done constantly (satellite TES) with and without storms.
    b. Earth has clouds.

    Your 4.
    a. Your relative errors hide problems. Alarm bells should have rung. Earth’s is by far the smallest, indicating parameters calculated from Earth fit Earth. Wow! But not the other 2 planets. Indicates the parameters/ fudge factors you used have been obtained from Earth’s, therefore not universal, and therefore wrong.
    b. Even the Stefan-Boltzmann Temperature for Mars, 209K vs Mars’ actual 214K, is more accurate than your model, despite its fudge factors!! (The fudge factors are drawn from AGW.)

    Compare with the results from my 3-page Chapter 2A. No fudge factors. (I didn’t actually present a back-calculation of Ts, the planet surface temperature, but shown below.)
    Venus Earth Mars
    Ts 735.3 288.2 214 (215*)
    Ts (Leveson) 715.8 288.4 228
    Ts (Carson) 734.6 287.6 215.3
    *I use this value from my references; indicates the size of experimental error.

    Despite your claim otherwise, you actually show AGW cannot reconcile the greenhouse effect on Venus, Earth and Mars. Your AGW-based model gives results well outside experimental error, showing the model is wrong. You are therefore giving further evidence that AGW is wrong.

    My theory does match data – no fudge factors – but differ considerably from AGW; you prefer the term “standard greenhouse theory”.
    For each planet, the greenhouse effect is proportional to the total pressure (and not to any IR gas), and GE/P = 5 (where P is in bar). This puts Earth’s GE at about 5 C and constant, the remainder (currently 27.6 C, the same as Venus’) results from variable Earth’s internal heat.

  11. 161
    Peter Carson says:

    #157 Phil.
    1. “ whereas hurricanes (and cyclones worldwide) are quite adequately explained in conventional climate theory – which you seem to flatly refuse to look at.”

    OK. Where’s your reference, please?

    2. “I imagine that you are having enormous difficulties with surface temperature on Venus using the Peter Carson Greenhouse effect.”
    Nope! Your vivid imagination is incorrect. Check my answer to Leveson … or you may even like to look at my Chapter 2A, heaven forbid! I match exactly!

    3. I looked you up. You seem to have a deal of geological knowledge. Do you see any error in my Chapter 2? (I’ve passed it by Uni of Adelaide’s Geology Dept’s Dr Victor Gostin; he seems to like it.)

  12. 162
    nigelj says:

    P Carson @160 etc, your problem is you don’t understand the principles. I’m not a climate scientist, but even I can see the huge holes in what you say. A chemistry degree is not the same as atmospheric physics, and coming up with alternative climate theories requires specialist study.

    More importantly, you don’t learn. It’s already been pointed out to you that Mars has a very thin low density atmosphere, and BPL noted it has no water vapour. Your website, calculations and articles takes no account of things like this, among several others, so your conclusions are false. You put the wrong information in, so the wrong information inevitably comes out.

    Instead of admitting this, and quietly backing down from your position in a sensible way, (as we all have to sometimes) you become ever more dogmatic and repetitive. I assume you know the Peters Principle – because you are a classic example.

  13. 163
    Ray Ladbury says:

    Re: Peter Carson

    Wow, the Dunning-Kruger is strong in this one!

  14. 164
    Peter Carson says:

    #162 nigelj: “you become ever more dogmatic and repetitive.”
    Are you sure you don’t use Dennis N. Horne as an alias?

    I’m a Physical Chemist. Seems that’d useful in studying atmospheric GASES. Also for studying ocean pH (Chapter 5).

  15. 165

    1. “However, it is nearly impossible to fit Venus, Earth and Mars at the same time without unphysical results (negative Fc) for at least one planet.”

    BPL: You seem to think I was talking about the model in general. I was talking about the fit to convective fluxes using the mathematical model of McKay et al. Not the whole AGW theory, or even my whole model.

    2. “The Intergovernmental Panel on Climate Change (IPCC, 2007, p. 9) estimates ∆T2X= 2.0–4.5K with feedbacks included, with a best estimate ≈3 K.” and
    “Hansen and Sato (2007) have suggested that long-term climate sensitivity is, in fact, about 6 K.”

    BPL: Do you understand the difference between Charney sensitivity and long-term sensitivity? Your comments here indicate you do not.

    3. “For Mars to absorb a higher sunlight proportion than Earth despite 200 times less atmosphere mass seems counterintuitive, but of course Mars has extensive dust storms – and low-altitude dust heats lower layers of atmosphere and thus the surface.”

    BPL: Mars is hotter near the surface during dust storms. This has been confirmed by probes on the surface.

    4. “7. Results for the solar system
    Temperature figures from the model were Ts = 715.8, 288.4, and 228.0 K for Venus, Earth, and Mars. More detail is given in Table 2. Relative errors were about 2.7%, 0.1%, and 6.5% for Venus, Earth, and Mars, respectively.”

    BPL: Those deviations are not bad for a semigray model, which is all my paper was about. If I had used full-scale radiative-convective models I could have gotten much closer, but I wasn’t interested in getting closer, I was interested in getting a quick-and-dirty model I could use for the Gliese 581 planets, assuming they were Earthlike. The fact that you got closer figures with your model means essentially nothing with a sample size of three. I could fit all three planets perfectly with a quadratic to one parameter, but it would have no physical meaning. That’s where your theory, and your critique of AGW falls down–your complete lack of understanding of the relevant physics.

    I recommend studying a book on the subject, and working the problems. Either Houghton’s “The Physics of Atmospheres” or Petty’s “A First Course in Atmospheric Radiation” would be good. For more involved math, try Goody and Yung 1989.

  16. 166
    Mal Adapted says:

    nigelj:

    Ray Ladbury, I would say people post crazy alternative theories for all sorts of reasons. Sometimes its just delusional but well intended lateral thinking,

    Nigelj is possibly the most diplomatic of RC’s regular commenters (for which we all love him 8^D). I, OTOH, wouldn’t say ‘well intended’. Denial is a private psychological defense mechanism against uncomfortable truth. IOW, it’s fundamentally selfish behavior. AGW pseudo-skeptics who aren’t trained climate scientists (and even some who are) are, at best, in denial of their Dunning-Kruger affliction. Although we should all be uncomfortable about AGW, climate realists can have only so much sympathy for those who’ve let their narcissism fool them into denying it.

  17. 167
    Mal Adapted says:

    More diplomacy (no sarcasm intended) from nigelj:

    A chemistry degree is not the same as atmospheric physics, and coming up with alternative climate theories requires specialist study.

    While I’m skeptical (heh) one can make peer-reviewed contributions to Physical Chemistry without actually knowing anything about it, I’m quite sure that’s not true across the breadth of climate-related disciplines. IMHO this is why the stubborn AGW-deniers can’t get past their DK affliction: they can’t accept that genuine experts aren’t just ‘smart’, but have painstakingly acquired broad, specific knowledge of their subjects, individually and in aggregate. AGW-deniers like Peter Carson simply won’t put the time in to learn just how incompetent they are!

  18. 168
    Phil Scadden says:

    Carson, a simple google search will find numerous educational pages about the conditions required for cyclones and why they occur in some places not others but since this is hardly radical knowledge. Virtually any meteoroloical textbook will do. eg the AMS “Our changing climate”.

    You contend “that AGW cannot deal with Venus, Earth and Mars’ Greenhouse Effect.” But that is only because you have imaginary greenhouse effect. Real theory predicts temperature and lapse rate on all planets. You do understand that GHE changes lapse rate? Can you predict it? Can you predict the spectrum on radiation received on surface and emitted to space?

    In short you can weave wierd and wonderful theories by imagined connections of observations, but to be taken seriously you have to something that is coherent with all the observations. And it is pointless to attack a theory as wrong when you patently dont understand it. I’m done. There is no sign that you have read any of the resources people have pointed you to or are ever likely to.

  19. 169
    nigelj says:

    Mal Adapted @166, thanks, however the stuff that goes on in my head is not so diplomatic at times. I just try to keep a lid on that.

    I agree to the extent that that most alternative theories about climate change are due to denial, selfish behaviour, and dunning kruger. I think you can probably add in politics, but all this appears to go together anyway.

    However I also think some people are just natural contrarians, or like playing with theories. Obviously the climate community thinks about alternative theories, but its just they are so obviously weak, they don’t require endless investigation that goes on and on, like we get from the denialists.

    For me I dont like to jump to firm conclusions about peoples motives, because I can’t be totally sure of them in some cases. I do think most, maybe 90% of climate scepticism is barking mad and not well intended. But given the difficulty of being sure about people, I try to attack bad ideas on the ideas. Sadly this can be time consuming.

    And climate scientists have to waste this time with complete denialist fools on occasion. Time and money down the drain. But it can be quite informative for me reading this sort of back and forward debate.

  20. 170
    Al Bundy says:

    nigelj: A chemistry degree is not the same as atmospheric physics, and coming up with alternative climate theories requires specialist study.

    AB: No, it primarily depends on brilliance coupled with interest. Interest is widespread but brilliance is amazingly rare amongst doctorally degreed Homo (so called) Sapiens. You’re making the mistaken assumption that education = the ability to create. The truth is that a billion years of education is no match for functional neurons. (Though, I suppose that “specialist study” does fit in that description, so I take it back… you’re more or less right.) And, of course, PC has shown a complete lack of brilliance, so the words he purveys to increase comprehension are pure goop.

  21. 171
    Thomas says:

    164 Peter Carson, I had a read of your pH chapter, based on your recommendation.

    I note this comment by your good self – “There’s been concern – hysteria even – that this increase in oceans’ CO2 will create acidity to endanger life in the oceans.” and “Therefore, as opposed to the doomsayers, ie AGW followers, one should be concerned with the (realistic) pH scale rather than the amplifying [H+] when one is discussing ocean alkalinity changes.”

    Man, you truly are on a mission. While I am reminded of the Jesuit Missionaries in Sth America and St Stephen in the pacific islands, and what happened to them.

    I have a question. Do you also deny the science of Coral Bleaching as well? It’s causes and prognosis between now and 2050?
    eg https://www.nature.com/articles/nature21707

  22. 172
    nigelj says:

    Peter Carson @164

    “Are you sure you don’t use Dennis N. Horne as an alias?”

    I definitely don’t, although the name is vaguely familiar from a NZ climate website.

    Yes chemistry and gas laws are relevant. However when I look at published climate research, it’s often by an multi disciplinary group of people. For a reason.

  23. 173
    zebra says:

    Mal Adapted #167,

    “AGW-deniers like Peter Carson simply won’t put the time in to learn just how incompetent they are!”

    ??

    But, this person obviously “puts in the time” to make his argument.

    I think sometimes that people use D-K diagnosis as a way to hide their own “denial” about human psychology and human behavior. It describes a narrow effect; it doesn’t really explain much.

    It’s a scary world out there, Mal. Lions and tigers and bears are nothing compared to the vast spectrum of human personalites with their fingers on various kinds of triggers, and we don’t like to think about it. Some are relatively innocuous, because they interact in the virtual world, but they are still immune to “sweet reason”, contrary to our fondest hopes.

  24. 174
    Jim Eager says:

    Peter Carson wrote “I’m a Physical Chemist.

    So is Eli. In fact, Eli is a Professor of Physical Chemistry.

    Don’t forget to pass the popcorn.

  25. 175
    Mike says:

    CCHolley @133

    If you make engineering decisions based on the assumption that since there is uncertainty in your numbers therefore no problem, then you are a fool.

    Exactly nowhere did I state “therefore no problem” thus making that conditional aspect of your criticism thoroughly specious.

    There are consequences to making decisions based on incorrect assumptions, often bad ones. I assert that with AGW there is no such option to “design for the worst case” because doing that could conceivably cause more harm than if nothing was done at all. If you believe that there would be little difference in the global economic impact in having to mitigate for an ECS of say 4.0 versus 0.5 then perhaps you are a fool?

    … with the most likely number to be 3 degrees. The paleo record would tend to confirm this to be about right.

    I’m unaware of a paleo record confirming an ECS of 3 degrees. I’d like to see a best example of that to learn how it was done.

  26. 176
    Mike says:

    Eli Rabett @131

    Dear Mike, from an engineering perspective if the best you have is a range estimates, you design for the most damaging.

    That is not always possible. In this case “designing” for the worst case could cause more harm than doing nothing at all should it turn out that the least case was correct. Not that I want to get into the weeds with natural paleo warming rates but there exists a maximum natural warming rate at or below for which no one should have any objection.

    There is also another point, which Eli calls the luckwarmers lament. Time does not stop at 2050, 2100 or whatever, but soon enough even a low value of ECS gets the world into a mess of trouble, just a bit later.

    Per the above, if we warm slowly, what’s the “mess of trouble”? Life did quite nicely when earth was a lot warmer. (Wasn’t the Sahara once a big swamp ‘only’ 100KYA?) At least can you admit avoiding another plunge into an ice age would be a big plus? Does someone actually know what global temperature would be “best”?

  27. 177
    Eli Rabett says:

    Peter Carlson, here and there:

    “All molecules emit ENERGY*

    Yeah, and Eli has a buck and Bill Gates has a buck, so all bunnies and billionaires have bucks.

    Peter Carlson:

    “Therefore, it’s only the total density at any particular height that determines how much heat in the form of IR is released, eventually to space.”

    What determines the level at which radiation of a particular wavelength is emitted to space is the optical density at the emitting level, which means the density of greenhouse gases which absorb and emit at that wavelength (see 152 for details).

    The optical density has to be low enough that an emitted photon can make it to space without being reabsorbed.

    Line by line calculations nail this

    What determines the rate of emission is the temperature at that level.

    Oh yeah, Eli was a Chemical Physicist, now he is just a lagomorph

  28. 178
    CCHolley says:

    Peter Carson believes he has undone at least 150 years worth of science including quantum mechanics, thermodynamics, and our understanding of heat transfer and radiation. Probably plate tectonics too. Not to mention the role of CO2 in keeping the planet warm which has been fairly well understood for at least 100 years. This while stating: ….my contention that AGW cannot deal with Venus, Earth and Mars’ Greenhouse Effect. Of course there is no anthropogenic contribution to Venus and Mars so of course AGW does not deal with it. Greenhouse gas theory on the other hand, yes. AGW, nope. But hey, he apparently knows all. Go figure.

    Fragments of Science, Popular Science Monthly / Volume 56 / March 1900

    Carbonic Acid and Climate.—The great importance of the carbonic acid in the atmosphere as a factor in determining the climate of the earth has been confirmed by the researches of a considerable number of investigators. Its work appears to be that of an absorbent of the sun’s radiant heat, retaining it and preventing its passing by us and leaving us in the cold temperature of space……

    Popular Mechanics / March 1912
    Remarkable Weather of 1911—The effect of the Combustion of Coal on the Climate—What Scientists Predict for the Future…..The furnaces of the world are now burning about 2,000,000,000 tons of coal a year. When this is burned, uniting with oxygen, it adds about 7,000,000,000 tons of carbon dioxide to the atmosphere yearly. This tends to make the air a more effective blanket for the earth and to raise its temperature. This effect may be considerable in a few centuries….

  29. 179
    nigelj says:

    Al Bundy @170

    I agree coming up with new theories depends on brilliance coupled with interest and ability to create. In fact Einsteins brain apparently has a lot of structures associated with imagination.

    But I think you need to appreciate coming up with an alternative climate theory also requires pretty specialist knowledge and training. Creativity and a high IQ will not be enough, or its unlikely.

    It needs at least a science degree, and I would suggest atmospheric physics as being the most relevant. Or alternatively, if you have a chemistry degree for example at least get someone to check your work, someone critical not just someone who will agree with you just to be nice, or alternatively team up with a few people. I don’t have the training needed for creating a climate theory.

    I do respect people who try to come up with alternative ideas of course. We need people like that. But yes, P Carsons theory doesn’t have a sense of brilliance about it. And good grief, a physical chemist claims climate change is caused by volcanoes, when there’s no evidence that volcanic activity has changed. Seriously? That seems like a failure at the first hurdle.

    People also have a responsibility when highly educated (often by the tax payer)not to spread garbage theories that misleads politicians etc.

  30. 180
    zebra says:

    Mike #176,

    ““designing” for the worst case could cause more harm than doing nothing at all”

    ” if we warm slowly, what’s the “mess of trouble”?”

    Standard self-contradictory Denialist reasoning.

    An engineering decision requires both… (1)what’s the harm in reducing emissions, and (2)what’s the harm if we don’t?

    Over decades now, I’ve yet to hear any Denialist give an answer to (1). Would you like to give it a try?

    Explain how “aaaaaahhhh…we’re all going to freeze to death in the dark…” if we replace fossil fuels at the upper bound of what is realistically physically possible? What exactly is this dire downside we should be worried about?

  31. 181

    M 176: Does someone actually know what global temperature would be “best”?

    BPL: Our entire global agriculture and civilization grew up when Ts was 287 or 288 K for something like 10,000 years. Any substantial deviation from that would be a disaster. Whether that temperature is “best” in some metaphysical sense is irrelevant. It’s what we need.

  32. 182
    Jim Eager says:

    Right, I forgot that Eli is now emeritus. My bad.

    Ray pretty well nailed Peter Carson early on @ 75.

  33. 183

    Al Bundy said:

    “And, of course, PC has shown a complete lack of brilliance, so the words he purveys to increase comprehension are pure goop.”

    Worse yet is his apparent utter lack of curiosity. He shows no sign of wanting to learn anything. Very strange for someone who’s spent as much time on education as he claims to have done.

  34. 184
    Alastair McDonald says:

    I am surprised that Eli did not point out to Peter Carlson that he was plain wrong when he wrote: “All molecules emit ENERGY”.

    Not all types of molecules emit energy, for instance, the noble gases e.g. Argon, although one could argue that it is not a molecule but an atom.
    However, homogenous diatomic molecules, such as O2 and N2, are definitely molecules and their main isotopologues do not emit energy. Although there are only a few examples of these gases, they form nearly 100% of the Earth’s atmosphere.

  35. 185

    Mike, #176–

    …there exists a maximum natural warming rate at or below for which no one should have any objection.

    Double fail:

    !) “Natural” does not always mean “good for humans/biota”, hence the term “natural disaster.” See, for example, the PETM, also known as “the Great Dying.” Had humans been around back then, I’m sure we would have ‘objected’ quite strenuously.

    2) Multiple temperature reconstructions have found that for at least the last two millennia, the globe was cooling, not warming. So no, there is no ‘natural warming rate’ in any normative sense. Or, to put it another way, the current ‘natural change rate’ would almost certainly be one of cooling, not warming.

    Here’s a prominent one that came out recently:

    https://www.nature.com/articles/nature25464

    Per the above, if we warm slowly, what’s the “mess of trouble”? Life did quite nicely when earth was a lot warmer. (Wasn’t the Sahara once a big swamp ‘only’ 100KYA?) At least can you admit avoiding another plunge into an ice age would be a big plus? Does someone actually know what global temperature would be “best”?

    First, we–and by ‘we’ I mean biological entities in general, including but not limited to humans–are not infinitely adaptable. While it is quite true that the faster the change, the harder adaptation becomes, it is also true that some limits are pretty firm. For instance, the ‘wet bulb’ temperature is a pretty firm one:

    “A person who is physically active at a wet-bulb temperature of 80 degrees will have trouble maintaining a constant core temperature and risks overheating. A sedentary person who is naked and in the shade will run into the same problem at a wet-bulb temperature of 92 degrees. A wet-bulb temperature of 95 degrees is lethal after about six hours.”

    https://www.nytimes.com/2015/06/07/opinion/sunday/the-deadly-combination-of-heat-and-humidity.html

    That does, in principle, get us back to the rate of change issue, because there are in theory potential physiological ‘fixes’. The most obvious one would be for humans (and other warm-bloods) to evolve higher body temperatures. How long do you think that would take? Alternately, how expensive would it be to genetically modify very large segments of the human population? Your answers to those questions should take into account that the projected timeline for this effect to become dangerous for gradually increasing numbers of people is basically several decades. (Remembering, of course, that AGW-related heat waves had already killed in excess of 100,000 people by the end of the first decade of the present century–so we are not now at a ‘zero harm’ level.)

    Of course, this is only one relatively ‘hard limit.’ Another is the thermal cap on the productivity of cereal grains. It varies a bit by crop, but basically all of our important crops stop growing well at high temperatures (meaning, roughly, above 30 C). Efforts are already well underway to do the requisite genetic modification–mostly by conventional selective breeding–to try to extend that limit to keep pace with a warming climate. But there’s no guarantee of success, or, if successful, of an indefinitely continued success in the face of continued warming.

    And a pretty intractable area is biodiversity and wildlife. Wildlife faces numerous threats today, most resulting from human impacts. This was discussed at length in Elizabeth Kolbert’s Pulitzer-winning book “The Sixth Extinction,” which I summarized here:

    https://letterpile.com/books/Elizabeth-Kolberts-The-Sixth-Extinction-A-Summary-Review

    Climate change is prominently featured as one of these multiple stressors (as, for marine environments, is ocean acidification, which Ms. Kolbert calls climate change’s “equally evil twin.”) Most biologists believe that a sixth great biological extinction is now underway. It’s both criminal–in that the loss is irretrievable on any humanly meaningful timescale–and criminally stupid–in that while the benefits humans derive from a well-functioning biosphere are difficult to trace in detail, they are almost certainly far, far greater than what we *can* already trace.

    But the main reason that I want to bring up the “Sixth Extinction” is because it contains a very good argument responding to your question as to ‘who knows what the best temperature of the Earth is?’

    The question is, “Best for who?” The best temperature for dinosaurs was clearly considerably warmer. But for current biota, one biologist quoted observes that living creatures descend from lineages that have been surviving repeated glacial cycles during the 2+ million years comprising the Quaternary period of geological time. Since we are currently in one of the warm ‘interglacial’ episodes, that implies that, prior to Industrial warming, we were already at the warm end of the temperatures to which our biota have adapted.

    That should be a sobering observation.

  36. 186

    “At least can you admit avoiding another plunge into an ice age would be a big plus?”

    Sure–although ‘big’ may be misleading, I think ‘plus’ is fair. Guy Callendar made the same point in his 1938 paper on AGW:

    https://hubpages.com/education/Global-Warming-Science-And-The-Wars

    However, that ‘comfort’ is vaguely analogous to a 50-year old getting a heart transplant from a 20-year old: in order to receive the the possible longevity benefit of the youthful heart, the recipient must first survive decades of a suppressed immune system function (not to mention the health and financial costs of massive surgical trauma.)

    And that understates the differential; in the case of humanity, we have a potentially existential threat, starting essentially *now* and extending for tens of millennia, in exchange for putting off a much slower-acting threat tens of millennia (or more) distant. (And one we already survived, actually, albeit not as agriculturists–let alone technologists in the modern sense.)

  37. 187
    Hank Roberts says:

    Victor Gostin, Associate Professor (retired), University of Adelaide, Australia

    signed this letter: http://globalclimatechangeweek.com/open-letter/

    Some issues are of such ethical magnitude that being on the correct side of history becomes a signifier of moral character for generations to come. Global warming is such an issue….

  38. 188
    zebra says:

    Eli Rabett #179,

    I may well be wrong on this, but did you mean to say:

    “What determines the rate at which a particular wavelength escapes to space…”

    ?

    I get confused by the way people use “level” and “height” on this issue. I have always imagined it as a “band” rather than a two-dimensional surface– where radiation emitted by a molecule at the bottom of the band is captured, or not, by the molecules above it. The “height” would be the surface that defines the bottom of the band, correct?

  39. 189
    Mal Adapted says:

    zebra:

    I think sometimes that people use D-K diagnosis as a way to hide their own “denial” about human psychology and human behavior. It describes a narrow effect; it doesn’t really explain much.

    Uhh. You may be confused by my use of ‘diagnostic’; I intend it to denote “characteristic of a particular species, genus, or phenomenon”, namely the pattern of self-deception evident in Peter Carlson’s comments. For the psychological definition of ‘denial’, I’m relying on that unimpeachable source Wikipedia 8^D! I’m not a psychological professional, so I’m not attempting to explain the origin of Mr. Carson’s stubborn rejection of the overwhelming evidence for AGW, nor his clearly mistaken belief that he’s competent to contradict the consensus of working climate scientists. As I’ve said here and elsewhere, the descriptive terms ‘DK-afflicted’ and ‘AGW-denier’ may be applied without needing to explain why someone would persistently reassert unsupported nonsense with such unshakable confidence, nor why they’re so uncomfortable with a redundantly-verified fact.

    <a href="Kruger and Dunning 1999 described a similar pattern the authors observed in their test subjects in controlled experiments. They likened it to medical anosognosia, but didn’t try to trace its neuro-psychological foundations. Bear in mind they were awarded an Ig Nobel Prize for it, having gotten their names attached in the popular imagination to a phenomenon that, once recognized in oneself, is painfully obvious in others 8^}.

    FWIW, my own ‘ouch’ moment came in 2008, when I first encountered the phrase “Dunning-Kruger effect” on the Internutz. I immediately ceased commenting on blogs when I couldn’t identify genuine experts on the topic, and I’ve made no claim to be an expert about any scholarly discipline since. Like AGW, f’rinstance: all I know about it is what’s in AR5 (and Weart’s The Discovery of Global Warming, etc), yet it’s apparent to me that Mr. Carson knows even less! I think both ‘DK-afflicted’ and ‘AGW-denier’ fit him pretty well, but YMMV.

  40. 190
    CCHolley says:

    Mike @175

    Exactly nowhere did I state “therefore no problem” thus making that conditional aspect of your criticism thoroughly specious.

    No you didn’t, but you did state that selecting an average ECS for a basis of decision making is “fools gold from an engineering standpoint” which may well be true, but the premise is false—we do not use an average, we use a probabilistic range. Other than the “fools gold” statement, you did not make a point, but then what is your point if not to imply there is not enough information to make a decision? Claiming there may not be a problem; therefore, do nothing, is almost the same as claiming there is no problem.

    There are consequences to making decisions based on incorrect assumptions, often bad ones. I assert that with AGW there is no such option to “design for the worst case” because doing that could conceivably cause more harm than if nothing was done at all. If you believe that there would be little difference in the global economic impact in having to mitigate for an ECS of say 4.0 versus 0.5 then perhaps you are a fool?

    I am well aware of risk mitigation relative to design decisions as that was a large part of my responsibilities over much of my career. A rather successful career I might add. The resources or costs spent in mitigating a risk is dependent on how we view the odds of a negative event occurring, the strength of our assumptions and/or knowledge, and on how bad the consequences of a negative outcome will be. A relatively low risk outcome that will result in a catastrophe can demand significant investment in mitigation.

    As for AGW, of course the economic impact responding to an ECS of 4.0 versus 0.5 would be different. However, mostly in the time value of money because even a relatively low ECS would have dire consequences, it would just take a little bit longer, but not so much longer as to not wreck havoc for future generations. Sea levels are already rising and accelerating fast enough to have huge economic impacts. But your point is moot anyway because the low end possible ECS is physically constrained as I explained before. The likelihood of an ECS of 0.5 is so small as to not even be possible. Even the lowest ECS within the realm of probability is still too high.

    Per IPPC: Based on the combined evidence from observed climate change including the observed 20th century warming, climate models, feedback analysis and paleoclimate, ECS is likely in the range 1.5°C to 4.5°C with high confidence.

    I believe the low end of 1.5 has been since discredited. It was based on observational analysis which was found to contain errors. Most likely low end is probably back to 2.0 degrees per previous estimates.

    I’m unaware of a paleo record confirming an ECS of 3 degrees. I’d like to see a best example of that to learn how it was done.

    Paleo confirms 3 degrees most likely. Review IPPC report. Also see:
    http://science.sciencemag.org/content/334/6061/1360.full?rss=1

  41. 191
    CCHolley says:

    Mike @176

    Not that I want to get into the weeds with natural paleo warming rates but there exists a maximum natural warming rate at or below for which no one should have any objection.

    Not really, the paleo has never shown warming at the rate we are currently experiencing. Not even close. It is unprecedented. The PETM took thousands of years. You could argue the paleo isn’t refined enough for the current period, but there is nothing to suggest that the current warming will not continue at its current rate as long as we continue to emit. The rate of warming is already causing ecological issues. Species will not be able to adapt fast enough.

    Per the above, if we warm slowly, what’s the “mess of trouble”? Life did quite nicely when earth was a lot warmer. (Wasn’t the Sahara once a big swamp ‘only’ 100KYA?) At least can you admit avoiding another plunge into an ice age would be a big plus? Does someone actually know what global temperature would be “best”?

    Being that you are the one who is concerned with the consequences of making bad assumptions, you should consider that it might be you who is making bad assumptions.

    There is no possibility of a low climate sensitivity and slow warming. We are already warming too fast. We’ve already taken care of the next ice age so that is not a consideration. Yes, the planet has been warmer in the past, but not during civilization. For civilization the best planetary temperature is a stable temperature. Of course overall there is no *best* temperature, but if we continue at some point it will be too warm in the lower latitudes for any kind of existence. Not to mention that there is no fertile soil at higher latitudes where the climate will be temperate enough to grow cereal grains. And what about sea level rise? How much is acceptable to you? Last time the atmosphere was at 400 ppm of CO2 sea levels were somewhere in the neighborhood of 85 feet higher than today. Does that sound acceptable to you? With thermal inertia those kinds of sea level rises are already in the bank.

    I’ll repeat it again, yes there is uncertainty in ECS, but no uncertainty that it is high enough to be problematic. None. Your assumption is wrong. And finally, it is quite possible your economic cost of mitigation assumptions are wrong. REMI study on a revenue neutral carbon fee and dividend plan say it would actually be an economic stimulus.

    The risk is high, the consequences dire, and the cost to mitigate reasonable. Any competent engineer who has properly vetted all the relevant information would easily make the right call on this one.

  42. 192
    nigelj says:

    Mike @176

    “Per the above, if we warm slowly, what’s the “mess of trouble”? Life did quite nicely when earth was a lot warmer. ”

    We aren’t warming slowly by paleoclimate standards, and human life was not around in a much warmer world. How the dinosaurs did is not relevant to us, and anyway climate change was a factor that wiped them out.

    Remember also that homo sapiens has evolved during a stable interglacial, and our biology and institutions and entire economic system is based around this. I think some people don’t see how integrated all this is, and how adaptation is not just about individuals, its about systems.

    Changes in flood frequency don’t need to be huge to be hugely costly. We have trillions of dollars of infrastructure, all designed to building codes based on certain flood frequencies.

    “At least can you admit avoiding another plunge into an ice age would be a big plus?

    Plenty of evidence suggests we have already cancelled the next ice age. We don’t need to burn more fossil fuels to do this. As below.

    https://www.edf.org/blog/2016/02/11/human-emissions-just-cancelled-next-ice-age-heres-why-we-should-care

  43. 193
    Peter Carson says:

    Eni Bunny #177. You don’t bother to read properly, do you? I guess it saves thinking.
    Why do so many here use pseudonyms? I suppose it allows trolls to hide their idiocy – but does show their lack of courage.

    I’m confident with ALL my contentions as I confirm them by matching them quantitatively with real data. That is the opposite of AGW which tries to force data to its models – applying various “forcings”, ie fudge factors, to change the data.

    I deal explicitly with IR emission in Chapter 1A – which you apparently choose to not read. I give a critique of the presentations of two of RealSciences contributors, Schmidt and Pierrehumbert. They contend the dip in the emission IR spectra at CO2’s wavelengths is proof that more CO2 will block more emission, and therefore cause more warming. I guess this is what you are referring to with
    “Line by line calculations nail this”

    Embarrassing for them, and many others, that dip varies with the height at which the satellite measurement is taken – exactly! They simply hadn’t taken into account the geometry! However, when the necessary geometry is included, their spectra show that adding more CO2 will have no effect on its emission, and warming – the opposite of what they wanted to show! It works out exactly for Venus and Earth (and semi-quantitatively at least for Mars, but probably completely quantitatively – if I can work out NASA’s complicated cataloguing system to get the measuring height for TES).

  44. 194
    Peter Carson says:

    #187 Hank Roberts.
    I thank you for pointing me to the Open Letter that Gostin signed; it was dated 2015.
    I only published chapter2 05May16. Vic’s 07Sep16 email opened
    “Wow! You certainly put a great effort into your new Ch2. well done.”

    … despite being originally predisposed towards AGW. Some people are able to be able to be persuaded by evidence to change their opinions.

  45. 195
    Peter Carson says:

    Phil Scadden #168 & #157.
    I see you are unable to find references I requested to support your assertion

    “ whereas hurricanes (and cyclones worldwide) are quite adequately explained in conventional climate theory – which you seem to flatly refuse to look at.”

    As you know, I was referring in particular to the 2017 US hurricanes which were unexpectedly large in size – and which I have answered in chapter 4a. The generalised explanations are not capable of doing so; in fact, probably do not explain any – quantitatively. Show me otherwise if you can.

  46. 196
    Mal Adapted says:

    climatemusings:

    If I thought that all climate mitigation dollars were coming directly out of helping poor people, then, yes, I might have second thoughts about aggressive climate mitigation.

    Yep. Lukewarmers will consider AGW a problem only when it directly harms them or the few people they care about. They’ll delay internalizing their marginal climate-change costs as long as possible. The poorest of the world’s poor, who live always on the edge of survival, will fall over it as GMST rises.

    To be fair, there’s abundant precedent for privatizing benefits and socializing costs while shouting “Won’t someone please think of the poors?!”

  47. 197
    Mal Adapted says:

    Sorry, wrong blog!

  48. 198
    Dennis N Horne says:

    @Peter J Carson. I explained to you on your own website that, whether you call them greenhouse gases or not, CO2, CH4, N20 behave differently from N2 and O2: GHGs absorb outgoing long wave radiation and N2 and O2 don’t. This is the basis of the greenhouse effect; Earth is at +15C not -18C. This is accepted by every climate scientist on planet Earth, including the hand-waving Judith Curry and head-in-the-clouds Richard Lindzen.

    As you still argued the point with me, I suggested you try your luck on this site, not realising you had tried it before. And learned nothing then either.

    You are like a religious fanatic whose faith in mumbo-jumbo deepens with ever-diminishing evidence.

    And no, I am not nigelj; I don’t see any similarities in style. He is comparatively polite, if long-winded, and I am pithy and to the point. To wit: you must be an embarrassment to U of Adelaide. Why can’t you just claim to be Napoleon or the Queen of Sheba or something?

  49. 199
    alphagruis says:

    Ray Ladbury #117

    So, actually, climate diplomacy is on track because a future, unproven, massive technology will save us ?

    I’m confused now, since I have been told repeatedly by the other amusing RE zealots here that present technology is already capable to readily save us… Their guru M.J. even felt the need to very recently publish yet another paper that once more “demonstrates” it.

    So funny.

  50. 200
    nigelj says:

    P Carson

    “I deal explicitly with IR emission in Chapter 1A”.

    Your chapter 1A is complete nonsense. I can see its complete nonsense, and more qualified people than me can see it.

    There are too many dogmatic people on this website with God complexes and obsessions.