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The Wall Street Journal downplays global warming risks once again

Posted on 22 September 2014 by dana1981

As has become the norm for media outlets owned by Rupert Murdoch, just before a half million people participated in the People’s Climate March around the world, The Wall Street Journal published an opinion piece downplaying the risks and threats posed by human-caused global warming. The editorial was written by Steven Koonin, a respected computational physicist who claims to have engaged in “Detailed technical discussions during the past year with leading climate scientists,” but who is himself not a climate scientist.

Koonin did admit that the climate is changing and humans are largely responsible, and noted,

There is well-justified prudence in accelerating the development of low-emissions technologies and in cost-effective energy-efficiency measures.

This is a step in the right direction. Unfortunately, Koonin’s editorial focused almost exclusively on the remaining uncertainties in climate science. Ironically, he stated,

Any serious discussion of the changing climate must begin by acknowledging not only the scientific certainties but also the uncertainties, especially in projecting the future.

But Koonin himself got the certainties wrong. For example, we know that humans are the main cause of the current climate change, responsible for about 100% of the global warming since 1950. However, Koonin’s editorial claimed,

The impact today of human activity appears to be comparable to the intrinsic, natural variability of the climate system itself.

This is simply incorrect. As climate scientist Michael Mann told Climate Science Watch in their thorough response to Koonin’s piece,

The fact is that the actual peer-reviewed scientific research shows that (a) the rate of warming over the past century is unprecedented as far back as the 20,000 years paleoclimate scientists are able to extend the record and (b) that warming can ONLY be explained by human influences.

Indeed, it is the RATE of warming that presents such risk to human civilization and our environment.

Climate scientists Michael Oppenheimer and Kevin Trenberth also took issue with Koonin’s assertion about the impact of human activity, saying,

Warming is well beyond natural climate variability and projected rates of change are potentially faster than ecosystems, farmers and societies can adapt to without major disruptions. Many details remain to be settled, and weather and natural variability will always mask some effects, especially regionally. But economic analysis of these risks supports substantial action beyond “no regrets” strategies. To argue otherwise as Koonin does is to ignore decades of research results.

Koonin primarily focused on the uncertainty in the specific impacts of continued rapid global warming. However, he glossed over the fact that those uncertainties range from generally bad impacts to potentially catastrophic impacts. Even in a best case scenario, climate science research indicates that we anticipate experiencing widespread coral mortality, hundreds of millions of people at risk of increased water stress, more damage from droughts and heat waves and floods, up to 30% of global species at risk for extinction, and declined global food production, for example.

Those are the anticipated impacts if we limit global warming to not much above 2°C warming as compared to pre-industrial levels. Accomplishing that would require intensive efforts to reduce human greenhouse gas emissions, and if we fail, the consequence will be far worse.

The good news is that slowing global warming can be accomplished with minimal economic impact. In fact, economic research consistently shows that reducing greenhouse gas emissions, if done right, is far cheaper than paying for the damages caused by unabated climate change. For example, a revenue-neutral carbon tax could create jobs and grow the economy. Two recent studies by the New Climate Economy Project and the International Monetary Fund likewise found that reducing carbon pollution could grow the economy, as summarized by The Guardian.

As Koonin noted in his piece, risk management is key in determining how to respond to the threats posed by climate change. On the one hand, we have a threat to the entire global climate on which every species on Earth relies, which humans are in the process of destabilizing at a rate more rapid than many species can adapt.

On the other hand, we have concerns about the impacts of climate policy on the economy. However, numerous studies have found that if done right, those policies can grow the economy, and will certainly be cheaper than paying for the damages of unabated climate change.

While uncertainties remain about whether the impacts of climate change will be bad, catastrophic, or somewhere in between, that’s precisely the kind of scenario in which uncertainty is not our friend. When faced with a risk to something so important, humans are usually smart enough to take action to manage that risk. For example, we buy home insurance, we wear seat belts, and fewer people now smoke than in previous generations who were unaware of the associated risks.

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Comments 1 to 46:

  1. Did you know that the RCP 8.5 temperature projections neglect to include positive feedbacks from methane and CO2 releases from melting permafrost?

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  2. Under the RCP 8.5 most aggressive scenario, the spatial structure of variations in the carbon resources in the active layer is similar to the one obtained from the results of numerical modeling in experiment Cs–2 with the maxima in the southern regions of the cryolitic zone of Eurasia and North America (see Figs. 2c, 2b). According to this scenario, the resources of organic matter released as a result of thawing of longterm permafrost ground by the end of the 21st century exceed 100 Gt C.


    DOI: 10.1134/S1028334X14030234

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    Moderator Response:

    [RH] Hotlinked url.

  3. jja@2: does anyone know what 100Gt C translates into as temperature rise?  I'm just curious.

    As for the WSJ article, perhaps its time to call the bluff on what Koonin and others are doing: they are offering the public a false choice.  To use an analogy, suppose you need to get downtown.  Person A says take the road on the left.  Person B says Person A is wrong.  Now, the WSJ kicks in and says, "Let's be fair and balanced about this: is Person A right or is he wrong?"  That is neither fair nor balanced: its a false choice.  You still need to get downtown; the proper choice is the road on the left or another road.  But Person B is not offering you a path downtown: he's just casting Doubt.  

    Koonin needs to tell us what the climate will be like by 2100.  Failing that, he needs to get out of the way and let the experts on stage.  Because 2100 is coming whether we like it or not.  Koonin must know he represents the profound wishes of the most profitable corporate sector in the history of commerce.  The fossils industries physically model everything they work with: oil fields, drilling rigs, refineries, coal deposits, trouble in the Middle East.  To say they are simply incapable of developing a 'path downtown', i.e. an opinion of what future climate will look like if we keep using their product, is absurd on its face.  They most certainly have an opinion, and just as assiduously want that opinion kept under wraps.

    We still need to get downtown, and the false balance offered by rags like the WSJ aren't helping us one iota.  Indeed, their primary purpose is to prevent the proper choice from ever being confronted.  Koonin is either being paid to help them or is too egotistical to see how he's being used.

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  4. In his article Koonin states,

    "For example, human additions to carbon dioxide in the atmosphere by the middle of the 21st century are expected to directly shift the atmosphere's natural greenhouse effect by only 1% to 2%."

    Anyone know what he is referring to when he says one to two percent?

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  5. JoeT@4:  There are people on these comments way more qualified to answer you than me, but just looking at the temperature effect, if 0ppm CO2 to 280ppm raises temperature by 60F (the greenhouse effect), then going up to 560ppm (a doubling) will only bring it up another 5F, or about 8%.  I'm sure the way he's doing it is in Watts/sq in or something but who cares.  It's severely disingenous.  He's claiming that the basis for comparison of the effect of AGW is with a planet with no greenhouse effect (also known as a ball of ice).  Well, sure, compared to such a planet, the effect of AGW is in the noise.  And compared to the Sun, Earth is cool.  So what?  The Real point is: does that 5 F matter to us mere humans.  Koonin excepted, apparently, yes it does.

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  6. ubrew12 @ 3

    2.12 GT of Carbon is equal to 1ppmv of CO2  so 100GT of carbon from melting permafrost is equal to 47ppmv of CO2.

    This means that the most agressive mitigation strategy through 2050, in attempting to stabilize at 450ppmv will significantly overshoot. 

    the reality is that permafrost carbon moves approximately 55% into the atmosphere in the form of CO2. So even this analysis is severely understated.  It looks like even the most agressive mitigation strategy won't stabilize below 550ppm.  This means that we have a significant job ahead of us removing CO2 from the atmosphere in an attempt to restabilize at 400ppmv.

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  7. ubrew12 @12, jja is correct.  Carrying the point through, however, only 55% of the emmissions, or 26 ppmv, are retained in the atmosphere.  That corresponds to an additional 0.25 C warming on top of that from a 450 ppmv concentration (which seems inevitable from directly anthropogenic sources alone).  That 0.25 C is based on the ECS, and for a short term response may be half of that.

    A better way to look at it, however, is that it is estimated that we can emit a cumulative trillion tonnes of Carbon and still have a reasonable chance of avoiding dangerous climate change.  We have already emitted 580 billion tonnes, so 100 GtC is 24% of our remaining allowance.

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  8. JoeT @4, CO2 contributes only 1 or 2% to the downward IR radiation at the surface (back radiation).  It contributes around 20% to the reduction in outgoing IR radiation to space relative to the upward IR radiation from the surface.  Another 75% or so comes from water vapour and clouds, and constitutes the water vapour feedback which many deniers claim does not exist.  It is the reduction in upward which constitutes the greenhouse effect, and the reduction in upward radiation that controls the energy balance equation that determines long term temperature trends.  The back radiation is important for weather, but in principle its effects can be replaced by changes in the rate of convection.  (There is, of course, no convection to space so that is not true of the outgoing IR radiation.)

    So, at base Koonan's claim is based on a simple misunderstanding that shows he completely misunderstands the nature of the greenhouse effect, or that he is completely dishonest, or that he is simply parroting memes provided by others without understanding what the mean and what they are related to.  The science really is settled on this one, so there is no fourth option.

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  9. JoeT @4, I misread what Koonin wrote and withdraw my post @8, no because it is wrong, but because it is no relevant to his claim.  (There really are deniers who argue the position I rebut there, which contributed to my confusion.)

    The "natural" greenhouse effect is the difference between the upward IR radiation at the Earth's surface (390 W/m^2) and the upward IR radiation to space from the top of the atmosphere (240 W/m^2).  Of that 150 W/m^2 difference 27 W/m^2 is from CO2, a further 13.5 W/m^2 is from other will mixed greenhouse gases including methane and ozone.  The remaining 109.5 W/m^2 comes from water vapour (61.5 W/m^2) and clouds (46.5 W/m^2). 

    Those values are for circa 1980 conditions, and hence include a significant portion of anthropogenic forcing already.  Hence the scare quotes on "natural".

    Based on RCP scenarios, by mid century greenhouse radiative forcing from anthropogenic sources is expected to increase by about 1.5 W/m^2, which is about 1% of the "natural" total greenhouse effect.  However, to obtain that figure, you need to only consider the change relative to current values.  If you consider the total anthropogenic forcing since 1760, that figure approximately doubles, and if you consider the business as usual forcing by the end of the century, it tripples.  

    Further, Koonan is carefull to only consider the "direct" effect.  The effect of water vapour and clouds are actually feedbacks on temperature.  If you drop temperature, they will fall, whereas if you increase it they will rise.  The result is that increasing CO2 also increases the WV and cloud greenhouse forcing (but also decreases, ie, make more negative, the cloud albedo forcing).  The effect is so strong that for a doubling of CO2, a 3.7 W/m^2 direct change in the total greenhouse results in a further 16.3 W/m^2 increase in water vapour and cloud greenhouse effect in feedbacks.

    So, by mid century the direct increase may be only 1 or 2%, but the total increase as a result of that direct increase will be a 5 - 10% increase in the total greenhouse effect.

    So, Koonan is not incorrect per se, but his claim is framed to cultivate confusion - and he fails to provide the explanation that would dissipate that confusion.

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  10. Tom Curtis@9: Koonan is no fool.  He absolutely knows that vapor is a feedback, not a forcer, in these matters.  He knows it, he knows it conflicts with the doubt he's trying to cast, and so he's leaving it out.  He's leaving out 80% of the actual AGW effect of raised CO2 levels, because it would work against the lie he's selling his audience.  His statement "human additions to carbon dioxide... shift the atmosphere... only 1%" is a lie to anyone with a smattering of Scientific knowledge... but it is legally correct.  It's written by Koonin the lawyer, not Koonin the scientist.  Hopefully he was paid at least 30 pieces of silver for betraying his training.

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  11. You make the comment  that  Steven Koonin "claims to have engaged in “Detailed technical discussions during the past year with leading climate scientists,” but who is himself not a climate scientist."  Two comments on that.  First and least important, I can appreciate why you use  the word claims but it does, at least to me, rather imply that Koonin might not actually have met with these "leading climate  scientists".  The comment that Koonin is not a climate scientist suggests he is not qualified to comment om matters climatic.  If that really is what is suggested, one might ask why such import is placed on the utterings of Sir Nicholas Stern, Professor Ross Garnaut, Professor Tim Flannery none of whom are climate scientists.  And Tom Curtis I wonder if Steven Koonin really doesn't understand the physics of the interactions between CO2 and incoming and out going radiation.  It seems very unlikely.  

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  12. Ashton:

    Pedantically, detailed discussions need not mean "met" in the conventional sense, in an era of long comment threads and email.

    Substantially, "leading" climate scientists is a bit of weasel wording on Koonin's part. Although understandable given typical word limits (I assume the column was also published in the printed version of the Wall Street Journal) (*), the phrase could refer to climate scientists with loads of high-impact, well-cited papers published, or it could refer to S. Fred Singer, Richard Lindzen, and other contrarians with little to no recent publication and an extensive history of being wrong - or indeed, to any mish-mash of scientists Koonin personally felt were sufficiently notable to describe as "leading". This ambiguity does not resolve if we presume total sincerity on Koonin's part, since we have abundant evidence of contrarians genuinely treating contrarian scientists with extensive histories of being wrong as "leading" climate scientists.

    With respect to your reference to Stern et al, I should remind you that Baron Stern, an economist, is usually referred to speaking within his domain of expertise, economics, in which case he is an expert, as is Professor Garnaut. For his part, Professor Flannery would be within his domain of expertise when discussing climate impacts on mammals (especially mammals in Australasia). I don't recall seeing Skeptical Science, or indeed any other science-based online source, rely on any of them for climate information outside their domains of expertise, although one could readily - and legitimately - include interesting or insightful things they have to say that illuminates the science. At any rate I do not see any justification for your apparent claim of tu quoque.

    (*) For instance, I wouldn't want to spend substantial parts of an op-ed I wrote just naming scientists I spoke to.

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  13. All,

    it should also be noted here that the 100GT carbon estimate for RCP 8.5 is a middle range estimate with other studies showing an estimate as low as 25GT Carbon and as high as 500+ GT Carbon.  There is over 1,600 Billion tonnes of Carbon in northern hemisphere permafrost. 

    In addition there is another 270-360 GT of Carbon in the sub-arctic peat, in FINLAND.

    This indicates an additional threat as the peat is already starting to burn in siberia and in the yukon territory.  There is potentially more Carbon emissions potential from subarctic peat fires than there is from degrading permafrost.

    I also doubt that the 55% atmospheric fraction will hold through 2100.  The IPCC AR5 projects an increase to 70% for the RCP 8.5 by 2100.  I expect, as with most projections from the IPCC RCP 8.5 scenario, that this is severely understated.

    If the natural carbon sources above grow at significant rates, they wll overpass anthropogenic emissions by 2050 (assuming an agressive mitigation effort).

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  14. The IPCC should produce a forward to the summary for policymakers stating a collective Mea Culpa to future human generations and a return of the Nobel prize as punishment for their fatal type I error aviodance bias.

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  15. correction:

    this comprehensive database indicates that global northern hemisphere peat north of 45' latitude contains 436 GT of Carbon. So the estimate given above is too high (for just Finnish peat carbon).


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  16. jja, from David Archer at Real Climate:

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  17. "For example, a revenue-neutral carbon tax could create jobs and grow the economy. Two recent studies by the New Climate Economy Project and the International Monetary Fund likewise found that reducing carbon pollution could grow the economy, as summarized by The Guardian."

    That's delusional. Growing the economy and tackling climate change are incompatible, as Kevin Anderson has shown. More broadly, economic growh destroys the environment, as the late Albert Bartlett so expertly pointed out.

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  18. TonyW, you might want to check your facts before declaring people "delusional".

    Kevin Anderson and Albert Bartlett are out of date. The price of solar energy has been dropping by 50% every few years. When you consider the economic benefits of stopping global warming (and ocean acidification), ending wars over fossil fuels, improving human health by reducing pollution, eliminating the massive global subsidies to the fossil fuel industry, et cetera... solar is already cheaper than any other major power source. Ergo, simply converting to solar will cause economic growth... and that's not even considering the near certainty that the cost of solar will fall by 50% again in the next few years... and another 50% within a few years after that. The costs of wind power and battery storage are also plummeting. It has been obvious to me for a few years now that these changes would inevitably make fossil fuels no longer cost competitive. Most economic analysts have now reached the same conclusions. Only the 'delusional' and mis-informed still argue otherwise... and by 2020 it should be obvious even to them.

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  19. I only picked up yesterday from a Crikey column that News International's second largest stockholder is Saudi Prince Al- Waleed Bin Talal Al Saud, the Kingdom's wealthiest Prince. Saudi Arabia's official International position is not unalighned to the current News Corp editorial policy.

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  20. TonyW - British Columbia implemented a revenue-neutral carbon tax in 2008. A 5-year review found that the province had reduced carbon emissions by 17%, with no discernable difference in GDP growth from the rest of Canada. And as a result of the carbon tax they how have the lowest personal income taxes in the country. 

    Every economic change has winners and losers - the Montreal Protocol for CFC's and protecting the ozone layer is a good example. While some established CFC manufacturers lost out, the cost/benefit analyses of that phaseout range from 1:2 to 1:11 depending on assumptions, not even counting the effect of reducing GHGs or a number of economic benefits. This represented a significant boost to the world economy by removing numerous costs to fishing, agriculture, and health. 

    Every economic indication for revenue neutral carbon taxes is positive - and they represent perhaps the most organic and least bureaucratic method of correcting the current lack of accounting for the externalities in fossil fuels. 

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  21. As far as I can see Anderson's analysis is based on historical data for economies.  This is not a good guide to what will happen if you try a something completely different (eg a pigovian tax on carbon). As KR points out, you now have data from BC to back that position.

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  22. Tom Curtis@9:  You said "So, by mid century the direct increase may be only 1 or 2%, but the total increase as a result of that direct increase will be a 5 - 10% increase in the total greenhouse effect... So, Koonan is not incorrect per se, but his claim is framed to cultivate confusion"  And where might we find that confusion first expressed, and most loudly, for the viewing public?  Today on Faux News (2:39 of a 5min video).  

    Gee, that didn't take long...

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  23. CBDunkerson

    Albert Bartlett's lecture can never go out of date (other than the data used to illustrate points) because it's based on maths and physical realities. Growth destroys the environment, as we've seen, but growth can't continue indefinitely, even if we could figure out how to grow without destroying the environment. The price of solar energy is irrelevant to this, though I doubt the world could convert to solar, due to resource issues and emissions of solar panel production. If it could, the world would have to operate on a much lower EROEI, so growth would end anyway. Kevin Anderson's analysis hasn't been shown to be in error either. By 2020, it will be obvious that either nothing will be done about the problem or that doing something about it unacceptably harms economic growth.


    As I understand it British Columbia was already on a downward track with emissions, before introducing that tax, so it's unclear what the impact of the tax has been, or how it has affected emissions in surrounding regions. However, BC is not the world. I'd welcome a revenue neutral carbon tax but it isn't likely, on it's own, to reduce emissions by the 10% per year needed to have half a chance (not 100% chance) of not exceeding the very dangerous level of 2C, though we'd breeze through the dangerous level of 1C.

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  24. TonyW - BC is a significant example in that their introduction of a carbon tax and it's lack of effect on GDP growth indicates that it is indeed possible to grow the economy and address climate change. 

    I agree that it's difficult to extrapolate from a single region to all situations, but I feel that BC's tax demonstrates a very promising strategy. 

    Moreover, there is reason to believe that GDP growth and energy consumption are not inextricably linked - Huang et al 2008, for example, found that there was no relationship for low-income countries, a positive correlation for middle-income countries (growth leading energy use, not the other way around), and actually a negative correlation for high-income countries; GDP growth from conservation and energy efficiency. I wouldn't consider that the last word on the subject, but it's pretty clear that the growth/energy linkage isn't as strong as many right-wing pundits would claim. 

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  25. Tony W @23, Albert Bartlett's mathematics is correct, but he applies it to the wrong quantities.  At least, he applies it to the wrong quantities for projecting potential future growth, although not for busting some of the absurd things that have been said about sustainability of growth based on fossil fuel use.

    The reason I can say that is that fossil fuel use is not a primary good.  It is not something we do for the pleasure of doing it itself (unless your a Top Gear presenter).  Rather, it is something we do to obtain the means to do something else, ie, to cook food, to be warm in winter and cool in summer, to communicate with the world over the internet etc.  Energy use is itself not a primary good, but it is a at least one step up the chain.

    So, Bartlett's lesson needs to be applied to energy use, and energy consumption if you want to recognize the true limits on growth.

    To start doing, so the total energy production of the human race amounts to the equivalent of 0.028 W/m^2.  That level of energy generation is not considered a problem in terms of global warming.  It follows that if we replaced fossil fuel energy production by some form of nuclear energy production, we could  fully supply the world's current needs, and potentially double it without creating more than local problems with regard to waste heat.  Unlike the case with fossil fuels, that is production which is sustainable in the sense that the fuels can be sustained for thousands of years, or at least they can with breeder cycles.

    That may not be desirable from your point of view.  It is, IMO, far preferable to falling back to human and animal power as the only sustainers of our civilazation for the simple reason that doing so will not sustain our civilization, and will not leave the surpluss of resources that is required for growth of knowledge and the bettering of the human condition.

    More importantly, however, 0.028 W/m^2 is just 0.012% of total solar power incident on the Earth's surface (allowing for no change in albedo).  Taping solar energy allows us to not just replace fossil fuel energy but to meet the energy needs of the probably (not quite) doubling of the human population of the comming century, while lifting global energy use per capita by a factor of 10 to allow the third world to grow economically, and still use only 1% of the global surface for power at 25% efficiency (or 2% at 12.5% efficiency).

    Looking at total available energy resources, therefore, we are not even close to the limits on growth.

    That does not mean solar energy is a formula for unlimited growth.  It is clearly not, and probably allows for continuing growth for another century or two.  In a century or two, of course, it may be possible to sustain further growth by moving factories, and food production of world to make use of more sunlight.  (Simply directing further sunlight at Earth with mirrors creates the same waste heat problem as nuclear.)  At its limit, such a process finishes with the construction of a Dyson swarm (or something further up the technological chain to the limit of a Dyson sphere).   Such a process can expand our civilizations potential energy use (and equivalent food production capacity) by a factor of 100 or more over current solar input to the Earth.  We need not move other suns to the Solar system (as per Bartlett's thoughtless ridicule), but merely use more of the Sun's total energy output - a process with a limit of approximately 2 billion times the Sun's current energy output (or using only 1% for energy 80 billion times our current energy usage.

    I do not know whether or not that will be technically feasible or desirable.  That is a decision for a later generation.  What I do know is that growth need not, and should not stop now, nor until the rest of the world enjoys a reasonable approximation of current typical western standards of living.  And I know that the later is quite possible using solar power.

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  26. Tom Curtis@9: I am still puzzled by the "1 or 2%" in Koonin's editorial.  I have thought that the total greenhouse effect is about 35C and is not that what he means?  (Not that the average reader would know or think that.)  However, if you say it would really be 5 or 10%, 1.75 or 3.5C more by 2050 sounds, too high and he is talking about the change from now until then, as I read it.  0.35 or 0.7C more by 2050 would seem to be more in the ball park.  I am wondering whether these numbers are reasonable.

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  27. ChrisK @26, I worked out the figures using the total forcings.  To convert to temperature change by 2050, you need to multiply by 0.4-0.55 to convert to the Transient Climate Response.  Hence, 0.4-0.55 C based on the figures I used.  (Those figures were based on eyeballing a graph, and so are not exact.  They are merely close enough for reverse engineering Koonin's claim, I think.)  

    If the change in forcing has time to reach equilbrium, the effect will be closer to 0.75 C, but that ignores the fact that we are not currently at equilibrium, so that there is another approx 0.5 C already in the pipeline.  That then works out as about 3.8% of the current total greenhouse effect in temperature at equilibrium.  As that total greenhouse effect is an equilibrium figure, you should compare equilibrium temperature estimates.

    That figure, is lower than the equivalent figure calculated in terms of forcing because (a) it ignores the Earth System Response which is also incorporated in the total greenhouse effect figure; and (b) as the temperature rises there is a smaller rise in temperature for each W/m^2 additional forcing.  (It is near linear over the range of forcings expected in the near future, but not over the total greenhouse effect.)

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  28. Tom Curtis,

    Thanks very much for replying to my question regarding Koonin's statement. I'm still trying to understand it better. I finally came across an article with footnotes in which Koonin explains his reasoning on the CUSP website of which Koonin is the director . Here is the relevant passage:

    [1] AR5 WG1 Figure 2.11 shows the global radiative balance, with the total downward flux on the Earth’s surface estimated as 503 ± 7 W/m2
    (161 W/m2 solar + 342 W/m2 thermal). AR5 Figure SPM.4 shows the total anthropogenic direct perturbation of this balance to be some 2.3 ±
    1 W/ m2, less than 0.5% of the downward flux. If the atmospheric concentration of CO2 were to rise to 550 ppm with all other anthropogenic effects unchanged, this perturbation would rise to be 3.9 W/ m2.

    I'm hoping that you might comment further. Thanks again!

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  29. JoeT - Thank you, that explains much about Koonin's statements. 

    Koonin expressing anthropogenic forcings as "1 to 2%" of insolation is akin to graphing the 0.9C warming over the last 150-200 years as Kelvin degrees with a baseline of oK - which has been done by denialists multiple times, appallingly enough. See Denial Depot for a rather amusing explanation of how this is done. He might as well have characterized the height difference between basketball player Yao Ming and a lawn gnome using a percentage of the height of the Empire State building. 

    In doing so Koomin is rather deceptively minimizing the extent of the changes, which at this time have increased temperatures to or beyond the peak value at any time in the Holocene, at any time during human civilization (Marcott et al 2013) - with more unrealized warming to come. That's a more realistic scale, one that more clearly describes how these changes will affect us. 

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  30. JoeT @28, thankyou for the sleuthing.  Given the footnote it becomes sadly apparent that I was right the first time.  I need to reinstate my comment @8, which discusses this misunderstanding, and withdraw my comment @9 (which while technically accurate, does not discuss Koonin's opinion).

    So specifically:

    1)  Koonin misrepresents the greenhouse effect as simply a function of backradiation.  That interpretation of the greenhouse is false, and has been known to be false for well over three quarters of a century.  In scientific terms, it is like criticizing the planning of the apollo missions because they will not work based on Aristotelian physics.  It is flat earth society material.

    As I said @8, "at base Koonan's claim is based on a simple misunderstanding that shows he completely misunderstands the nature of the greenhouse effect, or that he is completely dishonest, or that he is simply parroting memes provided by others without understanding what the mean and what they are related to. The science really is settled on this one, so there is no fourth option."

    2)  Although Koonin mentions the solar radiation, he appears to be caclulating his percentage from the 390 W/m^2 of thermal radiation (back radiation).  If he wanted to calculate the actual difference in backradiation, however, he ought to include the increase from feedbacks (WV and clouds) as well.  The total effect is an increase of approximately 20 W/m^2 (at equilibrium), or approximately 5% of the total back radiation at the surface.

    3)  Koonin does not even calculate the direct effect of the increase in CO2 accurately.  He appears to add the difference in radiative forcing for the change in CO2 (approx from the current 400 to the future 550 ppmv) to the current total anthropogenic forcing.  By excluding any changes in anthropogenic forcing other than that from CO2 he understates the change in anthropogenic forcing by mid century.  However, he does not state that he is discussing the change in anthropogenic forcing, but in the contribution of CO2 to the greenhouse effect, which makes it peculiar that he should us total anthropogenic up to 2011.  This does not, however, make any difference to his 1-2% value.

    Further, Keenan uses the TOA radiative forcing, not the change in CO2 contribution to the back radiation.  The two are distinct values both because of the higher temperatures and because overlaps with H2O are more significant for back radiation.  Again, this may not make a difference to the 1-2% estimate (due to the overlaps) - but Koonan does not know that.  The values he uses are not relevant to the percentage he estimates (which is  in turn irrelevant to the strength of the greenhouse effect).

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  31. Now that I went over Koonin's references, I think Tom's #8 is appropriate — the one he withdrew -— with bits of #9 thrown in as well. Post #8 is correct because Koonin really is looking at the downward radiation as the greenhouse effect, not the difference between the upward surface radiation and that at the top of the atmosphere. That's the difference between 342 w/m2from IPCC figure 2.11 and (398 - 239) = 159 w/m2. Then from SPM.5 (summary for policymakers) he takes the total anthropogenic forcing since 1750 of 2.29 w/m2. Then he does a net trick — he divides the 2.3 by 503 to get 0.0046, which indeed is less than 0.5% !!! That is he adds the incorrect 342 to the incoming solar radiation of 161 w/m2. Otherwise that number should really be 2.3/159 = 1.5%.

    Then he says assume by 2050 CO2 rises to 550 ppm. Then the increase in the forcing is 5.35 ln(550/400) = 1.7 w/m2. Add that to 2.3 and you get 4.0 w/m2 (Koonin says 3.9). Now 4/503 = 0.8%, so to get the 1-2% that he says in the WSJ, he must have taken 4/342 = 1.2%.

    Nowhere does he talk about sensitivity however and actual temperature change.

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  32. Tom, I was working on my own post and didn't see yours until I submitted it. I'm glad to see we both have the same conclusion.

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  33. JoeT's comment @38 quotes Koonin, and provides a link to the source. As soon as I read JoeT's comment and followed it to the original, I realized that Koonin was making a rookie mistake. Tom and Joe have provided good discussion; I'd just like to point out the following, which agrres with Tom and Joe:

    • Koonin compares radiative changes due to CO2 increases with surface energy balances. This is wrong.
    • What happens at the surface is highly complex, involved convective as well as radiative energy exchanges.
    • The role that increasing CO2 plays in climate is best represented by the changes in the top-of-atmosphere radiative exchange.

    Koonin is not the first to make this mistake. For example, in 1979, Newell and Dopplick published a paper reporting a much lower CO2 sensitivity than other papers had been suggesting. In 1980, Watts published a comment, pointing out the errors (including the mistake of looking at surface energy balances). Knewell and Dopplick responded, acknowledging errors. At one point, they even say "These criticisms are accepted. The situation appears to be much more complicated that [sic] we realized two years ago." This is how science works: publish, review, accept errors and move on.

    Koonin is at leat 35 years behind the times in the mistakes that he is making. I wonder how long it will take for him to be scientific and learn from his mistakes? He can clearly be scientific on other topics, but on climate change he's a pseudo-skeptic or dismissive.

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  34. Thanks Bob for the additional comments. I have to admit that I went to the Watts reference first, but was reassured that it was a Robert from Tulane, not an Anthony from nowhere. The articles were actually very informative, so thanks for pointing them out. As a member of the American Physical Society myself, it concerns me greatly that Koonin is (or was?) the chair of the APS committee tasked with rewriting the orgranization's position on climate change. It's the reason I was particularly interested in understanding his article.

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  35. Bob Loblaw @33, Koonin is even more out of date than that.  Arrhenius appears to have calculated the greenhouse effect based on back radiation, and the idea of a saturated CO2 effect due to Angstrom (1901) can almost make sense on that basis.  Callander in the 1940s, however, showed the greenhouse effect to have not been saturated using more detailed data on absorption at different wavelengths.  However, the model of the greenhouse effect used might still be considered a back radiation model.  That changes with Manabe and Wetherald (1967) which explicitly incorporates convection into the model, and explicitly models radation balance at the TOA.  Therefore, by 1967 at the latest, Koonin's theory was falsified and out of date.   He is ignoring 46 years of science he finds inconvenient, including, as you point out, a direct refutation of his theory.   

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  36. Tom:

    I agree that doing it right has been around a lot longer than 1979, and misunderstandings also go back further. The reason I picked Newell and Dopplick as an example was two-fold:

    • I knew of the study (and the comment/reply), having been exposed to it (and why it was wrong) as part of my graduate studies in the mid-1980s (i.e.. 30 years ago);
    • it was an example of the sort of mis-understanding that Koonin is making - but an example that appears in the proper scientific literature, underwent peer review, was properly critiqued in the same journal ("hey, you made some mistakes"), and where it received a proper reaction from the original authors ("oops"). Journal-published comments on bad papers are so rare these days that it is useful to have examples where they exist.

    The second point is germain to the fact that Koonin:

    • is making his points in non-peer-reviewed slop-eds and opinion papers;
    • is making mistakes that were somewhat permissible in the scientific literature 35 years ago (J Applied Meteo is a generally excellent journal);
    • is making mistakes that he has no excuse (other than willful ignorance) for making in 2014.

    If Newell and Dopplick tried to publish a similar paper today, in a respectable journal (not something like E&E or one of the off-topic or vanity press labels the denial indistry is fond of), it would likely not get published at all. Knowledgable reviewers would notice the mistakes immediately.



    As I knew it was Robert Watts (respected scientist), having read the comment decades before Anthony's blog was a gleam in a denialist's eye, it didn't even occur to me that someone might wonder if it involved Anthony. Thanks for a good laugh!

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  37. Tom or Bob,

    I think it's important for physicists such as myself (I'm a plasma physicist), who are essentially ignorant of climate science (but I'm trying to learn!) understand clearly what Koonin is saying. One more question if I may, just to make sure I have it right. The shocking thing to me from Figure 2.11 of the IPCC report is how huge the back radiation is, 342 w/m2 compared to the solar absorbed at the surface, 161 w/m2.  So if I look at a rough energy balance, then there is 159 w/m2 difference between the radiation output at the surface and that at the TOA. Now to get to 342, I need to add 84 for evaporation, 20 for sensible heat and 79 for solar that is absorbed in the atmosphere. That comes to 342 exactly. So, just to be pedantic about all this, the mistake Koonin is making is that he is including evaporation, sensible heat and solar as contributions to the greenhouse effect, rather than just the 159 w/m2. Am I saying that correctly? TIA.

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  38. Koonin is doing exactly what he has been commissioned to do, influence the APS/AIP climate change statement. I urge those of you who are APS or AIP members to write (paper/snailmail is much better than email) to pointing out his underhanded elisions and demanding a strong statement on climate change. The op ed is directed toward that smallish fraction of physicists who yet engage in denial. As for the rest, he is at a disadvantage, they are scientifically literate, can calculate and look up citations ...

    Note though, there is actually mention of a revenue neutral tax on fossil carbon. That, coupled with the Goldman Sachs downgrade of Peabody Coal indicates to me that the oligarchs are looking for an exit.

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  39. JoeT @37, first, for ease of discussion, here is the IPCC Fig 2.11 (which is discussed in Chapter 2 of IPCC AR5 WG1:

    It is an update of previous images by Fasullo and Trenberth, inferior in not showing the size of the atmospheric window (40 W/m^2 in the latest Fasullo and Trenberth image), but superior in showing the 95% confidence interval in brackets.  Not including the data for the atmospheric window means the energy balance cannot be determined for the atmosphere, but only for the surface and the Top Of the Atmosphere (TOA).  The legend of the image informs us that:

    "Numbers state magnitudes of the individual energy fluxes in W m–2, adjusted within their uncertainty ranges to close the energy budgets. Numbers in parentheses attached to the energy fluxes cover the range of values in line with observational constraints."

    (My emphasis)

    The important thing about figure 2.11 is that it only shows the energy balances.  It in no way shows the change in radiative forcing, and is in no way intended to show the greenhouse effect.  You can determine what is called the "total greenhouse effect" from it, that being the difference between the upward IR radiation at the surface and the upward IR radiation at the TOA.  That total effect, however, includes the effect of feedbacks that effect IR radiation (including WV, lapse rate, and cloud thermal feedbacks) as well as the direct effect of the total concentration of Well Mixed Greenhouse Gases, stratospheric water vapour, and ozone.

    To properly understand Koonin's error, it is helpfull to look at Fig 8.1 (from Chapter 8 of the WG1 report):

    "Figure 8.1 | Cartoon comparing (a) instantaneous RF, (b) RF, which allows stratospheric temperature to adjust, (c) flux change when the surface temperature is fixed over the whole Earth (a method of calculating ERF), (d) the ERF calculated allowing atmospheric and land temperature to adjust while ocean conditions are fixed and (e) the equilibrium response to the climate forcing agent. The methodology for calculation of each type of forcing is also outlined. DTo represents the land temperature response, while DTs is the full surface temperature response. (Updated from Hansen et al., 2005.)"

    The important thing here is to understand what is meant by radiative forcing, which is illustrated in Fig 8.1b.  It is the change in net upward radiation at the tropopause following a change in atmospheric composition or incoming radiation etc, after allowing the stratosphere to adjust temperature.  With a doubling of CO2 (approximately the situation Koonin considers), that change is 3.7 W/m^2.  To determine the percentage of that effect, you need to compare it to the net radiative forcing of relative to the situation with no greenhouse effect.  

    The total greenhouse effect is given by the difference between surface and TOA upward IR radiation, or 159 W/m^2.  However, 75% of that is due to clouds and water vapour, ie, due to feedbacks, and are not a "forcing".  The reason for that is that a change in those values will simply revert to equilibrium values in a short time.  So, the change in greenhouse forcing due to doubling CO2 is 3.7/(0.25*159), or 9.3%.  If the response of temperature to changes in forcing were linear (which they are not), that would result in an increase of temperature of 3.55 K before feedbacks (9.3% of 33K).

    Alternatively, we can see that increase is 1.6% of the TOA energy budget, leading to an linear 'expected' increase of 4.08 K; or a 0.9% of the net solar plus total greenhouse effect, leading to an linear 'expected' increase of  2.59 K.  

    Importantly, these are all TOA comparisons.  Because the radiative forcing is a TOA value (technically top of stratosphere, but the numerical difference with TOA is sufficiently small that it can be neglected), it can only meaningfully be compared to TOA values.  Koonin tries to compare a TOA value with a surface value, he is comparing apples to oranges, and demonstrating his complete failure to understand even basic theory of the science he criticizes.

    If Koonin wanted to make legitimate comparisons, he should really be making comparisons of temperature response.  The expected temperature response of doubling CO2 ignoring feedbacks is only 1.2C (+/-0.12 C).  That is only 0.4% of Global Mean Surface Temperature (GMST), but 3% of the temperature range consistent with the existence of human civilization.  Annual average temperatures below 0 C or above 40 C don't really concern us, because they are inconsistent with human flourishing.  It is the percentage change within that range that matters.  With feedbacks, that doubling pushes the response up to 6-12% of that temperature range.  With a GMST we currently have a small part of the Earth below that range (the poles), and no part of the Earth above it but nearly a third of the Earth is within 25% of the upper limit.  One doubling could push sizable portions of the Earth to the limit or beyond; while two doublings may make as much as a third of the Earth unsuitable for human civilization.  These are the percentages that matter.

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    Moderator Response:

    [TD] The second figure in Tom's comment has gone missing (only the caption shows).  Will somebody please fix it?

  40. Joe:

    In addition to the material provided by Tom, take a look at Hansen et al (1981) "Climate Impact of Increasing Atmospheric Carbon Dioxide", Science 213, 957-966. A copy is available on this NASA page.

    Figure 4 in that paper provides a result from a 1-d radiative-convective model, showing the first initial (instantaneous) response to doubling CO2, the changes a few months later, and the final changes many years later.

    • In the instantaneous case, increasing CO2 does cause a change in back radiation at the surface (+1.1 W/m2), but that is not what leads to warming. The key element is the change at the top of the atmosphere: a decrease of 2.4 W/m2 (a reduction of 0.8 from the surface, and 1.6 from the atmosphere). There are also changes in the surface-->atmosphere convective fluxes. If there was no top-of-atmosphere (TOA) change, then we'd just see shifts within the system, not necessarily an overall warming.
    • After a few months, the atmosphere has had a chance to adjust, but the surface has not - the ocean heat capacity is the key here, At this point, the TOA imbalance is actually greater - a net change from 1xCO2 of -3.8 W/m2.
    • Only after many years is the imbalance removed, after the entire system has time to warm. The net changes for the atmosphere, surface, and TOA (whole system) have re-equilibrated at 0.

    Koonin's mistake is to look at initial changes at the top of the atmosphere, and compare them to magnitudes at the surface. It's not the magnitudes that matter: it's the changes, and how the system reacts to counteract those changes (re-equilibrate).

    I know squat about plasma physics, so I can't come up with an analogy there. Perhaps a chemistry example? You have a chemical system that is in equilibrium, but it's highly active - mega reactions in both directions, at matching rates. You toss in a catalyst that slightly alters the reaction rate in one direction only. What happens?

    • It's not the change in reaction rate versus the original reaction rate that matters.
    • concentrations will change until the two rates balance again.
    • the new concentrations can only be predicted if you know how the two rates respond to the changing concentrations. If the rates change slowly with concentration, you need a large change. If the rates change rapidly, equilibrium is reached more quickly.

    [But I"m not a chemist, either, so this may be a crummy analogy.]

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  41. I don't know how relevant this is and, although rhetorical, it is certainly not very scientific.

    However, I have read, with great interest, all the threads in relation to this article, particularly Tom Curtis who is always informative. With some of the threads here questioning the veracity of the 97% of scientists who agree that AGW is real, there is a line from the movie "Ronin" which might be relevant to those who wish to cast doubt. It is "When there is doubt there is no doubt". It seems to me that uncertainty is doubt. So does that mean that the 3% of scientists who are uncertain have doubt which means they have no doubt. But what does this mean about their doubt? Does this mean they have no doubt that increasing greenhouse gases from anthropogenic sources WILL warm the planet OR mean that they have no doubt that increasing greenhouse gases from anthropogenic sources WON'T warm the planet. Now the first proposition is believed by 97% of climate scientists and there is plenty of evidence to support their position. However, if those arguing uncertainty have no doubt about proposition two, i.e. increasing greenhouse gases from anthropogenic sources WON'T warm the planet, then they haven't proven their case, which most certainly, doesn't provide a sufficient reason to delay taking positive action to alleviate anthropogenic greenhouse gas emissions.

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    Moderator Response:

    [RH] Please watch it with the all caps.

  42. Readers of this comment thread will also want to check out:

    The Climate Deniers’ Newest Argument, an Op-ed by Jeffrey Kluger posted by Time magazine yesterday, Sep 29, 2014.

    Like Dana,  Kruger critiques Koonin’s recent piece in the Wall Street Journal:

    The lede of Kluger’s op-ed:

    "It’s a lot easier to attack environmental scientists when you make up something they didn’t say—and then criticize them for saying it"

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  43. First time post. Hope someone sees this and it not too late.

    As an engineer I'm able to follow a lot of the math but not the details. Living in east texas I’m among a lot of deniers. Even other engineers who I would think would understand some basic science. Anyway a friend of mine often sends me articles that criticize climate change science and I try to respond but often don’t understand the details as I said. When I responded to his email he sent me regarding Noonin’s article using one of the comments here, he sent me the following reply.

    He is dead on accurate Hank. Koonin said the HUMAN additions to atmospheric CO2 are expected to shift the greenhouse effect by only 1% to 2%. That is perfectly in agreement with the fact that the totality of CO2 in the atmosphere contributes 25% of the total greenhouse effect in the atmosphere. What he's saying is that the 25% is going to increase to be 26% to 27% by the middle of this century.

    Your science sources are blooming idiots.”

    I was hoping someone could help me with a reply because I don’t understand what that reply is talking about.

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  44. Hank, your correspondent seems to be taking the view of the greenhouse effect I discussed @9 above, rather than Coonin's actual view.  As such, the relevant figures are:

    Total greenhouse effect c.1980: 150 W/m^2

    CO2 contribution: 20% (30 W/m^2)

    (Figures from Schmidt et al 2010)

    CO2 concentration c 1980: 340 ppmv

    Projected CO2 concentration for mid century with BAU (RCP 8.5): 550 ppmv

    Relative forcing: 2.55 W/m^2

    Change in CO2 forcing:  8.5%

    Assuming that CO2 is responsible for 25% of the total greenhouse effect reduces that to 6.8%.  Assuming the forcing change is from 2013 reduces it to 5.6%, or 4.5% assuming the 25% figure.

    The only way to reduce it to the 1% figure is calculate it as a percentage of the total greenhouse effect, ignoring the anthropogenic increase over the last 33 years, and ignoring the increase in the total greenhouse effect from water vapour related feedbacks.  That is, it requires first fudging the figures, and then making an apples to oranges comparison.

    The scenario as described, by the way, deliberately excludes all other well mixed greenhouse gases from the equation; and is chosen to ignore the fact that we are not in temperature equilibrium, and that consequently temperature changes from past forcings (including prior to 1980) are still "in the pipeline".

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  45. Tom I think I understand what you are saying. I need to go over it in detail ASAP. Thanks for you help.

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  46. Judith Curry has an op-ed in the WSJ  down playing the problem of AGW.  It is paywalled so I could not see the date.  I am sure Dana will have a reply soon.

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