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Why Levitt and Dubner like geo-engineering and why they are wrong

Filed under: — gavin @ 18 October 2009

Many commentators have already pointed out dozens of misquotes, misrepresentations and mistakes in the ‘Global Cooling’ chapter of the new book SuperFreakonomics by Ste[ph|v]ens Levitt and Dubner (see Joe Romm (parts I, II, III, IV, Stoat, Deltoid, UCS and Paul Krugman for details. Michael Tobis has a good piece on the difference between adaptation and geo-engineering). Unfortunately, Amazon has now turned off the ‘search inside’ function for this book, but you can read the relevant chapter for yourself here (via Brad DeLong). However, instead of simply listing errors already found by others, I’ll focus on why this chapter was possibly written in the first place. (For some background on geo-engineering, read our previous pieces: Climate Change methadone? and Geo-engineering in vogue, Also the Atlantic Monthly “Re-Engineering the Earth” article had a lot of quotes from our own Raypierre).

Paul Krugman probably has the main issue right:

…it looks like is that Levitt and Dubner have fallen into the trap of counterintuitiveness. For a long time, there’s been an accepted way for commentators on politics and to some extent economics to distinguish themselves: by shocking the bourgeoisie, in ways that of course aren’t really dangerous.


Clever snark like this can get you a long way in career terms — but the trick is knowing when to stop. It’s one thing to do this on relatively inconsequential media or cultural issues. But if you’re going to get into issues that are both important and the subject of serious study, like the fate of the planet, you’d better be very careful not to stray over the line between being counter-intuitive and being just plain, unforgivably wrong.

Levitt was on NPR at the weekend discussing this chapter (though not defending himself against any of the criticisms leveled above). He made the following two points which I think go to the heart of his thinking on this issue: “Why would anyone be against a cheap fix?” and “No problem has ever been solved by changing human behaviour” (possibly not exact quotes, but close enough). He also alluded to the switch over from horse-driven transport to internal combustion engines a hundred years ago as an example of a ‘cheap technological fix’ to the horse manure problem. I deal with each of these points in turn.

Is geo-engineering cheap?

The geo-engineering option that is being talked about here is the addition of SO2 to the stratosphere where it oxidises to SO4 (sulphate) aerosols which, since they are reflective, reduce the amount of sunlight reaching the ground. The zeroth order demonstration of this possibility is shown by the response of the climate to the eruption of Mt. Pinatubo in 1991 which caused a maximum 0.5ºC cooling a year or so later. Under business-as-usual scenarios, the radiative forcing we can expect from increasing CO2 by the end of the century are on the order of 4 to 8 W/m2 – requiring the equivalent to one to two Pinatubo’s every year if this kind of geo-engineering was the only response. And of course, you couldn’t stop until CO2 levels came back down (hundreds, if not thousands of years later) without hugely disruptive and rapid temperature rises. As Deltoid neatly puts it: “What could possibly go wrong?”.

The answer is plenty. Alan Robock discussed some of the issues here the last time this came up (umm… weeks ago). The basic issues over and above the costs of delivering the SO2 to the stratosphere are that a) once started you can’t stop without much more serious consequences so you are setting up a multi-centennial commitment to continually increasing spending (of course, if you want to stop because of huge disruption that geo-engineering might be causing, then you are pretty much toast), b) there would be a huge need for increased monitoring from the ground and space, c) who would be responsible for any unanticipated or anticipated side effects and how much would that cost?, and d) who decides when, where and how much this is used. For point ‘d’, consider how difficult it is now to come up with an international agreement on reducing emissions and then ponder the additional issues involved if India or China are concerned that geo-engineering will cause a persistent failure of the monsoon? None of these issues are trivial or cheap to deal with, and yet few are being accounted for in most popular discussions of the issue (including the chapter we are discussing here).

Is geo-engineering a fix?

In a word, no. To be fair, if the planet was a single column with completely homogeneous properties from the surface to the top of the atmosphere and the only free variable was the surface temperature, it would be fine. Unfortunately, the real world (still) has an ozone layer, winds that depend on temperature gradients that cause European winters to warm after volcanic eruptions, rainfall that depends on the solar heating at the surface of the ocean and decreases dramatically after eruptions, clouds that depend on the presence of condensation nuclei, plants that have specific preferences for direct or diffuse light, and marine life that relies on the fact that the ocean doesn’t dissolve calcium carbonate near the surface.

The point is that a planet with increased CO2 and ever-increasing levels of sulphates in the stratosphere is not going to be the same as one without either. The problem is that we don’t know more than roughly what such a planet would be like. The issues I listed above are the ‘known unknowns’ – things we know that we don’t know (to quote a recent US defense secretary). These are issues that have been raised in existing (very preliminary) simulations. There would almost certainly be ‘unknown unknowns’ – things we don’t yet know that we don’t know. A great example of that was the creation of the Antarctic polar ozone hole as a function of the increased amount of CFCs which was not predicted by any model beforehand because the chemistry involved (heterogeneous reactions on the surface of polar stratospheric cloud particles) hadn’t been thought about. There will very likely be ‘unknown unknowns’ to come under a standard business as usual scenario as well – another reason to avoid that too.

There is one further contradiction in the idea that geo-engineering is a fix. In order to proceed with such an intervention one would clearly need to rely absolutely on climate model simulations and have enormous confidence that they were correct (otherwise the danger of over-compensation is very real even if you decided to start off small). As with early attempts to steer hurricanes, the moment the planet did something unexpected, it is very likely the whole thing would be called off. It is precisely because climate modellers understand that climate models do not provide precise predictions that they have argued for a reduction in the forces driving climate change. The existence of a near-perfect climate model is therefore a sine qua non for responsible geo-engineering, but should such a model exist, it would likely alleviate the need for geo-engineering in the first place since we would know exactly what to prepare for and how to prevent it.

Does reducing global warming imply changing human behaviour and is that possible?

This is a more subtle question and it is sensible to break it down into questions of human nature and human actions. Human nature – the desire to strive for a better life, our inability to think rationally when trying to impress the objects of our desire, our natural selfishness and occasionally altruism, etc – is very unlikely to change anytime soon. But none of those attributes require the emission of fossil fuel-derived CO2 into the atmosphere, just as they don’t require us to pollute waterways, have lead in gasoline, use ozone-depleting chemicals in spray cans and fridges or let dogs foul the sidewalk. Nonetheless, societies in the developed world (with the possible exception of Paris) have succeeded in greatly reducing those unfortunate actions and it’s instructive to see how that happened.

The first thing to note is that these issues have not been dealt with by forcing people to think about the consequences every time they make a decision. Lead in fuel was reduced because of taxation measures that aligned peoples preferences for cheaper fuel with the societal interest in reducing lead pollution. While some early adopters of unleaded-fuel cars might have done it for environmental reasons, the vast majority of people did it first because it was cheaper, and second, because after a while there was no longer an option. The human action of releasing lead into the atmosphere while driving was very clearly changed.

In the 1980s, there were campaigns to raise awareness of the ozone-depletion problem that encouraged people to switch from CFC-propelled spray cans to cans with other propellants or roll-ons etc. While this may have made some difference to CFC levels, production levels were cut to zero by government mandates embedded in the Montreal Protocols and subsequent amendments. No-one needs to think about their spray can destroying the ozone layer any more.

I could go on, but the fundamental issue is that people’s actions can and do change all the time as a function of multiple pressures. Some of these are economic, some are ethical, some are societal (think about our changing attitudes towards smoking, domestic violence and drunk driving). Blanket declarations that human behaviour can’t possibly change to fix a problem are therefore just nonsense.

To be a little more charitable, it is possible that what was meant was that you can’t expect humans to consciously modify their behaviour all the time based on a desire to limit carbon emissions. This is very likely to be true. However, I am unaware of anyone who has proposed such a plan. Instead, almost all existing mitigation ideas rely on aligning individual self-interest with societal goals to reduce emissions – usually by installing some kind of carbon price or through mandates (such as the CAFE standards).

To give a clear example of the difference, let’s tackle the problem of leaving lights on in rooms where there is no-one around. This is a clear waste of energy and would be economically beneficial to reduce regardless of the implications for carbon emissions. We can take a direct moralistic approach – strong exhortations to people to always turn the lights off when they leave a room – but this is annoying, possibly only temporary and has only marginal success (in my experience). Alternatively, we can install motion-detectors that turn the lights out if there is no-one around. The cost of these detectors is much lower than cost of the electricity saved and no-one has to consciously worry about the issue any more. No-brainer, right? (As as aside, working out why this isn’t done more would be a much better use of Levitt and Dubner’s talents). The point is changing outcomes doesn’t necessarily mean forcing people to think about the right thing all the time, and that cheap fixes for some problems do indeed exist.

To recap, there is no direct link between what humans actually want to do and the emissions of CO2 or any other pollutant. If given appropriate incentives, people will make decisions that are collectively ‘the right thing’, while they themselves are often unconscious of that fact. The role of the economist should be to find ways to make that alignment of individual and collective interest easier, not to erroneously declare it can’t possibly be done.

What is the real lesson from the horse-to-automobile transition?

Around 1900, horse-drawn transport was the dominant mode of public and private, personal and commercial traffic in most cities. As economic activity was growing, the side-effects of horses’ dominance became ever more pressing. People often mention the issue of horse manure – picking it up and disposing of it, it’s role in spreading disease, the “intolerable stench” – but as McShane and Tarr explain that the noise and the impact of dead horses in the street were just as troublesome. Add to that the need for so many stables downtown taking up valuable city space, the provisioning of hay etc. it was clear that the benefits of the horse’s strength for moving things around came at a great cost.

But in the space of about 20 years all this vanished, to be replaced with electrified trolleys and subways, and internal combustion engine-driven buses and trucks, and cars such as the Model-T Ford. Almost overnight (in societal terms), something that had been at the heart of economic activity had been been relegated to a minority leisure pursuit.

This demonstrates very clearly that assumptions that society must always function the same economic way are false, and that in fact we can change the way we do business and live pretty quickly. This is good news. Of course, this transition was brought about by technological innovations and the switch was decided based on very clear cost-benefit calculations – while cars were initially more expensive than horses, their maintenance costs were less and the side effects (as they were understood at the time) were much less burdensome. Since the city had to tax the productive citizens in order to clear up the consequences of their own economic activity, the costs were being paid by the same people who benefited.

Levitt took this example to imply that technological fixes are therefore the solution to global warming (and the fix he apparently favours is geo-engineering mentioned above), but this is a misreading of the lesson here in at least two ways. Firstly, the switch to cars was not based on a covering up of the manure problem – a fix like that might have involved raised sidewalks, across city perfuming and fly-spraying – but from finding equivalent ways to get the same desired outcome (transport of goods and people) while avoiding undesired side-effects. That is much more analogous to switching to renewable energy sources than implementing geo-engineering.

His second error is in not appreciating the nature of the cost-benefit calculations. Imagine for instance that all of the horse manure and dead carcasses could have been easily swept into the rivers and were only a problem for people significantly downstream who lived in a different state or country. Much of the costs, public health issues, etc. would now be borne by the citizens of the downstream area who would not be benefiting from the economic prosperity of the city. Would the switch to automobiles have been as fast? Of course not. The higher initial cost of cars would only have made sense if the same people who were shelling out for the car would be able to cash in on the benefits of the reduced side effects. This is of course the basic issue we have with CO2. The people benefiting from fossil fuel based energy are not those likely to suffer from the consequences of CO2 emissions.

The correct lesson is in fact the same as the one mentioned above: if costs and benefits can be properly aligned (the ‘internalising of the externalities’ in economist-speak), societies and individuals can and will make the ‘right’ decisions, and this can lead to radical changes in very short periods of time. Thus far from being an argument for geo-engineering, this example is an object lesson in how economics might shape future decisions and society.


To conclude, the reasons why Levitt and Dubner like geo-engineering so much are based on a misreading of the science, a misrepresentation of proposed solutions, and truly bizarre interpretations of how environmental problems have been dealt with in the past. These are, in the end, much worse errors than their careless misquotes and over-eagerness to shock highlighted by the other critiques. Geo-engineering is neither cheap, nor a fix, and the reasons why it is very likely to be a bad idea are ethical and legal, much more than its still-uncertain scientific merits.

406 Responses to “Why Levitt and Dubner like geo-engineering and why they are wrong”

  1. 1
    Mesa says:

    “There would almost certainly be ‘unknown unknowns’ – things we don’t yet know that we don’t know. A great example of that was the creation of the Antarctic polar ozone hole as a function of the increased amount of CFCs which was not predicted by any model beforehand because the chemistry involved (heterogeneous reactions on the surface of polar stratospheric cloud particles) hadn’t been thought about.”

    A good point. Given this, why doesn’t this apply to our current climate models as well? In other words, why are we confident that our current computer models used in the IPCC predictions have any forecasting validity at all, especially since they haven’t demonstrated any forecasting success at long time scales, and all have exactly the problem described here of ‘unknown unknowns’.

    [Response: I made the point about even non-geo-engineering projections missing the ‘unknown unknowns’ above. That is clearly something to be concerned about (though not something that should make you any happier about our current trajectory). But you are fundamentally wrong about the models not demonstrating forecasting success. Models run in the 1980s projected continued warming of the magnitude that was seen, they projected stratospheric cooling, the impact of the Mt Pinatubo eruption, the amplification of the warming in the Arctic, the increase in water vapour, the increase in ocean heat content etc. etc. These predictions were not perfect, but they were clearly more skillful than assuming no change or some regression to the 20th C mean. – gavin]

  2. 2
    Simon D says:

    Fine point about geo-engineering requiring faith in climate models, a faith that many of the public proponents of geo-enginerring solutions do not have.

    Your post points to the responsibility that scientists have to be careful in discussing incomplete ideas or proposals with the press. Somewhere in the initial translation of geo-engineering (at least by sulfate aerosols) from scientific community to the media, the fact that it would require continuous action (ongoing injection of sulfate aerosols) not a one-time fix was missed. An almost Swift-ian modest proposal somehow became a cheap fix to a complicated problem.

  3. 3

    Your review is an encouraging sign that we can no longer accept such hype, tripe and misinformation.

    In the forgiving times of the past, it was not so necessary to question such popular messages. Now it is vital. Thanks.

  4. 4
    Mesa says:

    I guess my point was that clearly we don’t have any evidence of models being accurate at 50-100 yr time scales (no fault of anyone, just haven’t had time to run the experiment)…also climate model results depend on sensitive counter-balancing effects of positive and negative feedbacks which are incredibly susceptible to the ‘unknown unknown’ problem. Longer time scales just make this problem worse.

  5. 5
    PaulW says:

    Sulfate engineering is in many ways analogous to some of the early suggestions for clearing smog from Los Angeles:

    LDs arguments false choice of mitigation vs “behavior change” is really amazingly naive.

  6. 6
    CM says:

    What have you got against Paris?

    [Response: I love Paris, but it hasn’t been the most effective city at dealing with its dog poop externality. – gavin]

  7. 7
  8. 8


    A beautiful piece of work here. Thank you.

    Freakonomics is on my short list of favorite non-fiction books but now I am wondering if Levitt was wrong about many things in his first book. Because I am far from expert on those issues, was I fooled like many will be fooled by Superfreaknonics’ treatment of climate science and geoengineering?

    Maybe, just maybe, the public will get the correct message because of the backlash to Levitt’s incorrect message?

  9. 9
    Radge Havers says:

    Well stated by Krugman, but I’d go further.

    In the first place, in order for snark to be truly clever, it has to be on target. Other than that, a lot of what’s wrong with discourse (on any topic) these days is that’s it’s dominated by gratuitous snark — just one grand vociferous expression of facetious arrogance from the political peanut gallery. You’d think it would have gotten old long ago. It’s an indication of lack of imagination in our culture that people never seem to tire of this clownishness, IMO.

  10. 10
    BJ_Chippindale says:

    I again point out that Cheap Access To Space (and building Mirrors there) does not have the same set of negatives as making still more changes to our Atmospheric Chemistry.

    I agree fully that it would not solve the problem of CO2 completely. The oceans would still be absorbing it, but it could keep us under the level at which tipping points take things out of our control.

    It could buy us some precious time even when the warming has become an undeniable fact and the deniers have become converts or simply been crucified by the general population.

    It could provide us with a source of power that is undeniably green 24×7.

    Understanding that there would be other potential issues with creating such a system and its control of weather, the ability to tune the albedo in response to the real results measurable on our real planet means less need for perfect modeling.

    The point I repeat is that this would be cheap and easy compared to getting everyone to agree to actual effective cuts at Copenhagen. It would permit us to recover the climate from far deeper into the AGW process than we can manage through changes to our own CO2 output. It would in effect, allow the climate itself to silence the bulk of the denialsphere and still let us have a chance of recovery.

    It plays to our strengths (which include aeronautical engineering) and avoids some of our weaknesses (the tendency of nations to act like spoiled children on a schoolyard).


  11. 11
    john Atkeison says:

    I read the excerpt from the book in the Sunday Parade magazine today. It is outrageous “don’t worry, somebody will fix it” drivel.

    “The people benefiting from fossil fuel based energy are not those likely to suffer from the consequences of CO2 emissions.”

    We will all suffer– that’s an implication of why we call it *global* warming. Here in New Orleans it was the poor working class who suffer the most. But in the upper middle class neighborhood of Lakeview, there were also rooftop rescues and there are still empty and partially destroyed houses.

    It is an important fact that those who have contributed the least to the problem are those hit hardest and first, especially in the global sense. (I am happy to report that our daily paper also carried the Maldives underwater story prominently as well.)

    Thanks for the discussion!

  12. 12
    RonalLarson says:

    The term “geoengineering” has only recently come to include a new approach called “Biochar” – the intentional manipulation of the carbon cycle. In one version of this approach, pyrolysis results in about half the carbon content becoming a charcoal which is called Biochar when placed into soil. The sequestration period is generally now conceded to be be millennia (larger in northern climes). In another version, (called hydrothermal carbonization – HTC), the conversion is almost entirely to a char-like solid. In both cases, hundreds (maybe thousands) of ongoing experimental test plots are proving what ancient Amazonians proved thousands of years ago – huge improvements in soil productivity. In the Amazon, the improvement (still continuing to this day) is about 300%, with a technology known as “Terra Preta”. The Japanese have practiced the same for centuries, with numerous scientific papers. In the first (termed “slow pyrolysis”) approach, roughly half the carbon is available as gases and/or liquids. Both approaches require no or minimal external thermal input to carry out the atmosphere-saving chemical conversion – that some term reverse photosynthesis.
    The Biochar community has largely steered clear of the Geoengineering community, for the reasons expressed by Gavin. But 6-7 weeks ago the Royal Society (RS) brought the possible inclusion to the fore ( Biochar proponents think that the RS scoring was less than half of what it should have been. If it is to be included by anyone as Geoengineering (and thankfully no-one involved so far has done so on this list), please look more closely at the benefits (many wedges of both carbon neutral AND carbon negativity being possible) than did the RS. I know of no anti-Biochar claim that can’t be readily refuted.
    Biochar proponents are almost unanimously agreeing with this list – that we need to be attacking the main climate disruptor: excess CO2. I’d love to hear of objections similar to Gavin’s that apply to this direct remediation approach, which will also add employment, rural economic development, nitrous oxide, and peak oil crises we face. Being the new kid on the block, the main things Biochar needs to take off are more publicity and being replaced in the draft UNFCCC document for Copenhagen. I’d love to hear objections on why Biochar is NOT the right solution – as well as whether it should be called Geoengineering.

  13. 13
    CM says:

    Sorry about the silly Paris question. This is a fine and timely essay. The memorable image of needing 1-2 Pinatubos a year, in perpetuity, is worth far more than a thousand words of technical discussion.

    I was also happy with the points made about human behavior. You may be right that noone has ever suggested as a plan to solve the climate problem that individuals consciously modify their behavior all the time. But it’s not hard to see where people might get that impression. How many books, feature articles etc. on global warming don’t culminate in a “10 things you can do to save the planet” box, exclusively targeting individual consumer behavior and appealing to conscience? They all too rarely start with: “1. Vote for people who say they’ll raise taxes on fossil fuels. 2. Join a campaign to get others to do the same.”

  14. 14
    Thomas says:

    Very well stated Gavin. I find myself on both sides of the geo-engineering issue. On the one hand, I think the time will soon arise, that because of our tardiness in solving the emissions problem, we will be forced into trying geo-engineering of some sort. If this is indeed the case, we don’t want to have created too much knee-jerk resistance to the idea. On the other hand, as you point out, high CO2 plus an amount of geo-engineering calculated to bring the global average temperature (or any other single degree of freedom metric you care to use), back to near where it would have been in the undisturbed system, is still a different planet than we started with. My contention, is that high GHG concentrations plus countervailing geo-engineering is likely to be less different than high GHG alone. But, clearly the movement to use the possibility of a geofix as an excuse to avoid or delay necessary changes does needs to be nipped in the bud.

    The other argument I see too infrequently, is that a transformation away from fossil fuels will be necessary anyway. So we are not fighting about whether we need to transition away from them, but rather about the timing of the transistion. And given that we are already seeing the beginnings of real problems due to the ending of cheap oil in sufficient quantities for BAU level demand, I contend that that inevitable transition is going to forced upon us one way or another a lot sooner than most realise.

  15. 15
    Alexandre says:

    Since economics were to some extent brought into discussion, I would suggest the RC fellows to make a future post about Elinor Ostrom, who won this year´s Nobel Prize in Economic Sciences.

    Her work has a lot to do with the many dilemmas we face mitigating AGW.

  16. 16
    David B. Benson says:

    RonalLarson (12) — Biochar as a soil amendment clearly works in the tropics and appears to be benificial in temperate zones. In neither case should too much be added into the root zones; radish starts won’t in 30% biochar, for example. In temperate zones about half the biochar re-eneters the active carbon cycle within decades; the othr approximately half persists for centuries to millennia, perhaps many of the latter.

    There are many web sites about biochar. Here is one:

    Below the root zones there might be no limit but nobody knows, AFAIK. In any case there is no econoimic incentive for the gardener or farmer to do so. If a plan of verifiable carbon credits for this could be devised and enforced, all the better. Make biochar and compress it (like coal), bury deep (like coal) and it will last for millions of years (like coal); artifical coal seams.

    It is probably the case that there is not enough excess primary production, world-wide, which if turned into buried biochar, would offset the approximately 7–9 billion tonnes of excess carbon added per year. One proposal is then to artificially increase primary production. Here is an achievable plan to do so:
    Irrigated afforestation of the Sahara and Australian Outback to end global warming
    (the pdf is open access, just click the internal link in the abstract)

    Is the application of biochar a form of geo-engineering? I would say yea, but then I say yes to the wide-spread adoption of artifical fertilizers as well.

  17. 17
    Mark says:

    “I guess my point was that clearly we don’t have any evidence of models being accurate at 50-100 yr time scales”

    We don’t have any evidence they won’t.

    Especially since over 50-100 years they will improve still further.

    But we DO have evidence that being good over 50-100 years is eminently plausible. 40 year old models which are cruder and have more unknowns unmodelled in them have been right for 40 years.

    Why the belief that the better ones we have no will mysteriously break then?

    It IS after all an unsubstantiated claim. And requires proof.

    Got proof?

  18. 18
    paulina says:

    Thank you.

  19. 19
    Schmert says:

    The World Health Organisation are estimating a 50,000 per annum death toll from the use of Sulphur Aerosols, so if the intention is to save the planet and consequently the human race, that certainly would be counter intuitive !

  20. 20
    Mark says:

    “I again point out that Cheap Access To Space (and building Mirrors there) does not have the same set of negatives as making still more changes to our Atmospheric Chemistry.”

    The building space mirrors though is expensive and unworkable. How big IS that half-degree wide burny thing in the daytime?

    Access to space is expensive. For the same value we could reengineer our cities to use 15% of the power it currently consumes.

    Access to space is not cheap. We do not have space elevators and fuel rockets are expensive. Especially in terms of CO2.

    You are technically right, your idea doesn’t have the same downsides. It does however have a whole slew of downsides peculiar to itself.

  21. 21
    Marion Delgado says:


    Yes. But both winners’ work does. We shouldn’t neglect Oliver Williamson, either.

  22. 22
    Schmert says:

    (as little as i care about being contraversial, in terms of Geo-engineering, i’ve never seen mention of more Oxygen! ozone (trioxygenate)the biosphere’s sun screen, and the depletion of which means more UV radiation, which cannot possibly be helping the polar melt rate? I was flicking thru a few papers a while ago on whatever i could find relating to trioxygenate and it appeared to be a reaction process of oxygen with UV radiation, so the actual reaction, is oxygen’s process of UV absorbtion, if so that would make the solution more oxygen, that would also force the CO2 down so the oceans can do there carbon sink thing, feed plankton etc, and no-one’s going to die as direct consequence of oxygen, so that’s most likely the problem !?)

  23. 23
    Marion Delgado says:

    Schmert 50,000 per year is not much of a death rate for a planet of almost 7 thousand millions. Just saying, that wouldn’t be the best argument against it.

  24. 24
    James Staples says:

    This is like watching a Drug Addict trying to ‘Rationalize’ his/her abuse; these Carbon Junkies, and there little “Surely we can get in at least one more ‘Hit'” before it all comes crashing down.
    Oddly enough, on a personal note, some people have been trying to hand ME that same kind of stuff – but then that’s what I get for being a Medicinal Cannabis Activist, as well as a Climate Activist!
    Since their all ‘Corporate Shills’ of one kind or another……..

  25. 25
    RichardC says:

    …”The existence of a near-perfect climate model is therefore a sine qua non for responsible geo-engineering, but should such a model exist, it would likely alleviate the need for geo-engineering in the first place since we would know exactly what to prepare for and how to prevent it.”…

    I disagree. With a near-perfect climate model we would be able to figure out exactly where, when, and how much of each substance to inject above and/or into the atmosphere/ocean. It wouldn’t provide a magical way to alleviate the need. We don’t need any climate model to know that we need to Stop Spouting CO2!

    A plan would have to be combined with an epic transition to nuclear and/or renewables

    The dump-quicklime-in-the-ocean geoengineering idea includes ocean acidification mitigation. They say it would take 2500GW of power. That’s gotta be a mistake. 2000 full-size nuclear plants going 24/7?

    Geoengineering testing would be of NASA’s scale. Assuming we have at least a decade (famous last words) before the arctic sea ice disappears, then that gives ten years of testing before a pressing need (tipping point) for geoengineering might arise. The tests would also greatly advance climate science and improve climate models. The Met Office just estimated 2060-2080, and we can possibly do something by then, but if it’s 2020 or before, then wouldn’t it be nice to have some tests done before we make such a decision?

  26. 26
    Gail says:

    Not to beat a dead horse, speaking of horses – but when it comes to known unknowns, here’s what we do know:

    1. Gasoline emissions ultimately result in ozone; ethanol emissions ultimately wind up as peroxyacetyl nitrates. Both can travel long distances from their source.

    2. Ozone and PANs are well known to be toxic to humans (cancer, emphysema, asthma) and vegetation.

    3. Vegetation is dying – in the California Sierras, in the midwest, and the Eastern Seaboard of the US. Reports are in from old-growth forest in Yosemite, about Sudden Aspen Decline in the Rockies, and documented at The bark beetle infestation is often blamed for decimating the vast swaths of the western pine populations, but research shows that ozone encourages insect depredation on trees, as well as lichen growth.

    What contribution is ethanol making to this widespread demise of trees and other plants? We don’t know, because the Environmental Prostitution Agency isn’t tracking ethanol emissions, or if they are, they’re not telling – in fact, they want to increase the proportion already mandated to be added to gasoline.

    That will make the corn growers happy – for a while. And it will enable some to pretend burning biofuels will liberate us from foreign oil – even though when the costs of oil-based pesticides and fertilizers, growing with diesel-fueled equipment, processing and transporting are figured in, it becomes clear ethanol is nothing but a green fraud.

    And what will it mean when our trees, the foundation of our terrestrial ecosystem, are gone? The same as when coral reefs are destroyed – mass extinctions for all the species dependent upon them.

    Unless we’re willing to say goodbye to shade, nuts, fruits, and wood, geoengineering is not a solution.

  27. 27
    Sili says:

    Alternatively, we can install motion-detectors that turn the lights out if there is no-one around. The cost of these detectors is much lower than cost of the electricity saved and no-one has to consciously worry about the issue any more. No-brainer, right?

    You obviously don’t have a cat.

    [Response: Fair point. Though in my defense I was more thinking about office situations than domestic ones.- gavin]

  28. 28
    Gareth says:

    One more reason, and the equal (at least) of any other, why geoengineering of any kind can not replace steep emissions cuts: ocean acidification.

    (PS: Buenos Aires is at least as bad as Paris, based on a visit a few years ago…)

  29. 29
    Schmert says:

    ‘Schmert 50,000 per year is not much of a death rate for a planet of almost 7 thousand millions. Just saying, that wouldn’t be the best argument against it.’

    that is conservative estimate, what they did mention is whether or not they are intending on re-spraying the SUV, and where they think they can hide if they taint my Starbuck’s Latte !

    so in real in terms, the death toll is probably best left at them getting run-over ?

  30. 30
    john Atkeison says:

    I’m starting to feel like deja vu all over again.

    There was something of a sea change in how the public viewed Global Warming around 2003-2004. The tide turned significantly in my experience on the street, and more people seemed to be taking us seriously.

    In the years since, more of this *deflection* has risen, but with the same effect as the denial: NO MEANINGFUL ACTION.

    In fact, now Business As Usual is now dressed up for the party and steps out with real attempts to deal with the problem– they are calling the combination “climate legislation.” But in no case are we presented with an opportunity to strike at the heart of the situation with anywhere near the speed, scale, or scope necessary.

    In this situation, I am skeptical of any fix other than rapid down-scaling of fossil fuel use in a populist style. Just Do It!

  31. 31
    pete best says:

    I personally would that that the energy aircraft carrier USA will turn itself around energy usage wise regardless of the political and economic will anytime soon. The same might apply to China, Europe and India for that matter and hence 30 billion tonnes of CO2 per annum is scheduled to grow by that period doubling time of 2 to 3% per annum or emissions doubling in 70/2 = 35 years or in 70/3=23 years which is alarming to say the least.

    In those short years to our doubling of CO2 emissions we would have released/emitted between 1 to 1.5 trillion additional tonnes of Co2 which in real terms 2 to 3 times the total emissions to date from 1750. If you take these emissions projections to the middle to the end of the century and assume that peak fossil fuels do not matter much and we continue to grow our energy usage then lets make it a nice round 2 trillion tonnes of additional CO2 and say its another 500 ppmv of CO2 added to our atmosphere. So the future is warmer and the rate of change is potenitally a little too fast for our planet and its inhabitants to handle.

    For the optimists we can do the following:

    Invest in CCS and clean up coal.
    Invest in renewable energy sources (CSP, Wind, Geothermal, wave etc)
    Mesh it all goetehr via a new supergrid (HVDC Cables etc)
    Make efficiency a priority (electrical goods, new thermal homes and buildings etc)
    Eliminate the ICE vehicle and replace then with the electric vehiclce future.
    Change our eating habits and reduce our meat usage
    stop decimating our forests and even restore them
    Change some of our hanits – consumption and materialism maybe

    for the pessemists:

    Its all over becuase the present infrastructure is just too expensive and pervasive to replace in any meaningful time frame and hence the only hope is to geoenginer our way out of this issue to some degree.

    I will go for the former one personally.

  32. 32
    mike roddy says:

    I’ve read the Superfreakonomics chapter, and it’s so terrible that the effect will end up being positive. Levitt and Dubner will find themselves being invited to address the Heartland Conference, appear on the Rush Limbaugh show, and sit down for dinner with people like Dan Blankenship and George Will. Talk about a living nightmare!

    Out of desperation, the authors will renounce and then rewrite that chapter for future editions, in a desperate attempt to restore their shattered reputations. This will be good for the advancement of climate change knowledge.

  33. 33
    JCH says:

    SInce my Great Grandfather became a rich man raising mules and draft horses (from 1875 until the 1920s), I would be remiss to point out that one choice is to return to using them. If people hate the smell, then why does just about evert city have horse transport in their quaint, inner-city neighborhoods. It stinks. So what? It’s apparently mood-makin’ romantic. Modern veterinary medicine makes it unlikely many horses would die while at work.

    A great deal of the fossil fuel used in agriculture and transportation could be eliminated by reverting to real horsepower. The jobs created would eliminate intensively fossil-fueled jobs, and they could not be shipped overseas. It would be very easy to construct oder-free, to their neighbors, stables.

    Horses and mules are a very efficient means of converting cellulose to energy, and the conversion is essentially GHG neutral. The jobs are low skill and for a lifetime, and we have plenty of F-through-C students to fill them.

    “You got to have smelt a lot of mule manure before you can sing like a hillbilly,” – Hank Williams

    And then there is sail power.

    We already know how to run a modern world in a largely carbon-free way. The fully globalized companies that would become ExxonMobil once shipped their products all over the world in sail-powered oil tankers, and delivered it to customers with horse-drawn tankers.

    To a cowboy, it makes a lot more sense that screwing up our only sky with some crazy-butted experiment just because you’ve gotten so far from your raisin’ that Old Bessie is a pejorative. Your Great Grandfathers would have taken you to the woodshed, or worse.

  34. 34
    mike roddy says:

    I can’t add to your excellent summary of geoengineering, Gavin, but know something about infrared motion detector lighting controls. Actually, I am a distributor of them, or, more often, hotel keycard systems that send a RF signal to the thermostat, indicating by the key’s placement in a slot whether a guest is in the room. This saves much more money than lighting controls, since hotel rooms use 85% of their energy on the HVAC system. Most hotels in the US- unlike those in Europe- drain away huge amounts of energy keeping the room heated or cooled at the perfect temperature when nobody is in there.

    Our products save 25-40% on room energy use, and with rebates, tax credits, and asset appreciation, it should be an easy sell to hotel GM’s. Except that it’s not. Most hotel rooms in the United States keep that wall heat pump humming all the time. This is in spite of the fact that the economics of the product are fantastic- payback is 1-2 years. This is not exactly a small issue, since there are millions of hotel rooms in the United States.

    The reason is human behavior from an unexpected source. Guests don’t mind either infrared or keycards, but hotel GM’s think they would object, so don’t buy our products. They are terrified of losing guests to a hotel down the street, since here it’s an unusual product (though standard in, say, Berlin, Rio, or Tokyo). Hotels want to project an image of abundance and luxury, which is an American behavior trait as much as anything.

    My business is out of Southern California and Washington state. The product is, but I can be reached at We’re not the only manufacturers, but total market share of keycard systems- which save more energy than infrared motion detectors- is less than 1%. I’m puzzled and a bit frustrated. Advice welcome.

  35. 35
    Peter Backes says:

    Surprised you didn’t point out the glaringly bad basic science knowledge Levitt displayed on NPR:

    (speaking about sulfer dioxide)

    “If you put it at the North Pole and the South Pole, is where you really want to put it to cool the Earth”

    Huh? Gee, and all these years I thought the sun was strongest at the equator…

    “it turns out you need about as much as would come out of a regular garden hose.”

    Hmmm, I know Pinatubo spewed out a lot more material than sulfer dioxide but I gotta believe it was a bit more sulfer dioxide than a garden hose’s worth…

    [Response: He’s quoting Nathan Myrhold who thinks that 100,000 tons of SO2 (a year?) in the polar region stratosphere is enough to cool the planet, and that he can deliver it there via a ‘garden hose’. I find this very hard to believe and have seen no studies that would support a significant forcing from such a small amount (for reference, Pinatubo – peak forcing around -3 to -4 W/m2, put something like 20 million tons of SO2 into the stratosphere – 200 times as much). – gavin]

  36. 36

    Sorry, off topic, but I hate really bad examples. Paris pre-automobile produced
    all its fruit and veg from within the city limits … thanks to the productivity
    boost which horse manure gives to any gardening. Horse manure was always a valuable

  37. 37

    Actually, I think Milano is worse than Paris on that one point.

    When awareness of the AGW problem comes into context of self interest of the individual, there will be more significant progress on mitigation and adaptation (the trickle up effect). Sooner the better of course, but there in lies the quandary.

    Chasing geo-engineering solutions that are not viable on multiple planes, will hinder or retard progress and ability to address effectively. All the little ducks need to be in a row to prevent sillyness and throwing money at bad ideas that are merely on the plate because of various interests that would benefit.

    In other words the benefits need to be aligned with the self interest of the human race, not merely those that are good at generating proposals and getting funding. Otherwise, we risk capacity to cope in a changing/evolving economic landscape.

    It’s very good to have articles like this one to keep perspective.

  38. 38
    Gail says:

    Actually, some of us equestrian types rather enjoy the smell of horse manure. At the very least, we respect it, and use it to enrich our gardens.

  39. 39
    Tony O'Brien says:

    How will the biosphere respond to a world without seasons? How will we respond where the heat of the day and cold of night are meaningless concepts? Do we really want Alaska and Florida to have the same climate?

    Does not more CO2 plus geoengineering equate to a world without differences? When the airlines were forced from the sky the days were hotter and the nights colder.

  40. 40
    david says:

    A while ago I read a blog post by levitt about an article in the nytimes on peak oil. I was similarly unimpressed with their reasoning. The NYtimes piece they were referring to was well written and referred to a range of viewpoints – they criticised it on the basis that the views reported contradicted each other, even though they were clearly attributed to different people. Like their attitude to the climate, their general take was “don’t worry, technological advances will fix it”.

    By the way sili, the cat probably considers himself to be “someone” (although whether or not he wants the lights on is open for debate).

  41. 41
    GlenFergus says:


    Why can’t I buy a compact fluorescent bulb with a motion detector built in? How much would it add to the cost?

  42. 42
    Gail says:

    Here is the definitive answer to crazy desperate plots to geoengineer.

    Now, just stop it! Shut up! Dead oceans = dead people, period.

  43. 43
    mdc says:

    [Response: He’s quoting Nathan Myrhold who thinks that 100,000 tons of SO2 (a year?) in the polar region stratosphere is enough to cool the planet, and that he can deliver it there via a ‘garden hose’. I find this very hard to believe and have seen no studies that would support a significant forcing from such a small amount (for reference, Pinatubo – peak forcing around -3 to -4 W/m2, put something like 20 million tons of SO2 into the stratosphere – 200 times as much). – gavin]

    So to be clear – we need, at worst case, 2 of these eruptions’ worth of SO2 per year, each of which is equivalent to 200 garden hoses running continuously? So we need 400 garden hoses? This is supposed to be crazy/impossible? Granted the ‘garden hose’ isn’t an SI unit, but then nor is the ‘volcanic eruption’, and both seem to be being used for the same purposes (to trivialise or exaggerate the amount of material needed respectively, without stating quantities).

    In the book it is claimed that the price tag for the SO2 solution is $250m. You seem to be saying this is 400 times too low. Ok, so the new price tage is $100bn. Let’s double this because projects like this always overrun. This is still less than 20% of the $1.2tn annual spending Stern proposes. I’m no expert on this, and your other points are persuasive, but we’re not talking peanuts here – we’re talking sums that, when subject to compound growth are the difference between your great great grandchildren living in (relative) poverty or not.

    So let’s not call Lavitt an idiot career-focuses demagogue just yet.

  44. 44
    Chris Colose says:

    I would still recommend Alan Robock’s “20 Reasons Geoengineering may be a bad idea”

  45. 45

    To paraphrase that same former Defense Secretary- as far as Levitt and Dubner are concerned- ‘You go with the planet you’ve got not the planet you think you want’.

  46. 46
    tokyo requiem says:

    On human behavior:

    Levitt just keeps on digging doesn’t he? I wonder if he is even vaguely familiar with the work in economics on the effects of institutions on human behavior. You know, the work that won Douglass North that prize from the Swedish Central Bank? Perhaps he should do a little (more) reading, and this time within his own discipline. Or indeed any of the texts on social contract theory that make the explicit point that institutions are built by us in order to shape our behavior.

  47. 47
    Jeffrey Davis says:

    I love the contradiction that the geo-engineering people are proposing fixing a problem that doesn’t exist. According to them.

    That can’t be emphasized too much.

  48. 48

    RichardC said

    The dump-quicklime-in-the-ocean geoengineering idea includes ocean acidification mitigation. They say it would take 2500GW of power. That’s gotta be a mistake. 2000 full-size nuclear plants going 24/7?

    At one time that URL led to a scheme where pulverized and oceanically dispersed lime — not quicklime! — would capture atmospheric CO2 by forming bicarbonate ion. Maybe the scheme has deteriorated. The energy cost of pulverization and dispersal is obviously many times less than that of pulverization, calcination, and dispersal, and including the calcination step only doubles, or slightly less than doubles, the sequestration potential of a tonne of limestone.

    In any event, this remediation method, already inadvertently demonstrated, also takes very little energy compared to limestone calcination, but gets the same four moles CO2 per mole of metal that quicklime would get.

    It would even allow coal-powered CCS: one coal-fired electricity plant build on Mg2SiO4-rich terrain, and dedicated to pulverizing and dispersing it, could take down the CO2 put up by eight such electricity plants.

    (How fire can be domesticated)

  49. 49
    Jim Eager says:

    Re mdc @44: you are overlooking the cost of addressing the other very serious harmful impact of higher atmospheric levels of CO2, namely ocean acidification and it’s impact on the marine food chain, which Levitt and Dubner ignore completely.

  50. 50
    Patrick 027 says:

    Excellent post!


    Re Schmert 22 – producing oxygen requires energy and it would not react with CO2 in the air. However, a net increase in oxygen would result from biochar. But it would be very very very very small compared to the oxygen content of the atmosphere.

    Re JCH 33 – “If people hate the smell, then why does just about evert city have horse transport in their quaint, inner-city neighborhoods. It stinks. So what? It’s apparently mood-makin’ romantic.”

    I think it’s a difference in amount/concentration. (The fewer the horses, the more people appreciate them.)

    “Modern veterinary medicine makes it unlikely many horses would die while at work.”

    That won’t stop animal abuse and neglect – though changing attitudes since that time might.

    PS yes, horses can convert cellulose to energy (right? – or maybe the bacteria in their guts use it (although those bacteria might then supply some service. I’ve even read that without bacteria in the human womb, development of the embryo?/fetus is adversely affected) – I don’t know); However, I’ve read that muscles are only 20 % efficient at converting calories to mechanical energy. Then consider how much more efficient a wheeled vehicle can be to a legged vehicle (unless we’re talking kangaroos??) – or maybe not (legs lift up, gain potential energy, swing forward, go down, maybe it’s more efficient than I thought), but at least a wheeled vehicle can have regenerative breaking. I suppose you could affix some devices onto a horse’s body that would collect and channel mechanical energy to reduce losses in stop-and-go traffic, if the horse can adapt to it…