The Big Knob

March 22nd, 2006

Posted by: Roger Pielke, Jr.

In 2000, we wrote a paper titled, “Turning the Big Knob: Energy Policy as Means to Reduce Weather Imapcts.” The metaphor implied that some viewed energy policies as a means for decision makers to tune the atmospheric concentrations of greenhouse gases in such a way to modulate the number or intensity of extreme events, and thereby also modulate the resulting societal impacts. Frequent readers of Prometheus will know that this subject has been the subject of many discussions on this site of late, and will know that we think that while there are good reasons for concern about climate change, and for reducing GHG emissions, the Big Knob strategy is a loser when it comes to disaster impacts.

Upon hearing from several critics of our work comments to the effect that no one really believes that GHGs can be used to intentionally modulate hurricanes or their impacts, I thought it worth showing the figure below. This was part of a major media campaign by a leading (and typically very thoughtful) environmental group last fall focused specifically on hurricanes (not GHG reductions generally). This image was taken from their WWW site at the time. See the Big Knob?


10 Responses to “The Big Knob”

  1. John Fleck Says:

    Which typically very thoughtful environmental group?

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  3. Chip Knappenberger Says:

    Nice, Roger!

    I am still chuckling aloud at this picture in light of the treatment your comments got over on RC.


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  5. Paul Dougherty Says:

    There are many of us who accept AGW but who are classified as deniers, skeptics, etc. because we do not buy the big knob approach that solves everything by turning down CO2. Some equally concerned scientists see nothing but that knob, get frustrated when someone (who?) doesn’t turn it down and so they bang their heads against the wall.

    But there are other approaches to this huge problem. For example in 2003 NASA reported that perhaps 25% of global warming was caused by carbon soot. A 2006 NASA paper states that 30% to 50% of Arctic warming may be due to ozone. Then today I read that Geo. Phy. Ltrs. has a paper saying that a natural cause, the sun, may have caused 25% to 35% of the 1980 to 2000 global warming.

    Neglect all of the other “more minor’ anthropogenic and natural forcings and the above still adds up to almost 100% for the Arctic. So where does carbon dioxide fit in Arctic warming?. Those conclusions make it look to me that if you eliminated all of the human CO2 you would not do a thing to help those Inuits and polar bears. Yet here is a specific region where alternative policy could have dramatic effects.

    Ozone and black carbon are pollutants. That word turns a few heads. They are less costly to control than CO2… a few more heads turn. Results could be seen far sooner than even the immediate elimination of anthro-CO2 would produce. More turning heads. You could then move beyond this and go after CO, CH4, NH3, etc. and get even bigger results. What would the markets be doing to fossil fuel consumption and alternative energy while all of this was going on? There is dramatic new activity on this front already but the effects on CO2 are further out.

    It would sure be nice if the blogosphere started looking at other forcings besides CO2. It would be even nicer if alternative policies were then developed and accepted with scientific support. In the meantime we can all call each other names and bang our heads against the wall. I believe that a different scientific perspective, (is it too late?) and an examination of alternative policies would save a lot of skull damage.

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  7. Andrew Dessler Says:


    I have a question for you: do those people advocating the “big knob” approach intentionally misrepresent the peer-reviewed consensus, or are they just misinformed? In other words, is there an “excess of objectivity” here, so that they’re argument is as valid as yours, or are they going against the scientific consensus?


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  9. Markk Says:

    I have just been discouraged by reading an article related to this topic, and reading this just made me have to respond.

    Did you know if you advocate spending money on direct effects of “hazards like floods, storms, and droughts” you are now “justifying further inaction” on greenhouse gases. It says so right in the Talk of the Town Section in the March 20th New Yorker. The article sets up that this line of thought, planning for direct effects, is just “business as usual” which will lead to an “practically a different planet” since the “underlying cause” is not dealt with. HELP!

    This is a horrible argument! It pits people who will actually have an impact on millions of lives – zoning boards, regulators, corporate strategists planning within regulations – as opponents of other people who could also affect millions of lives, those working to curtail our inefficient use of fossil fuels and reduce greenhouse gas emissions. These are not opposed groups, they are not using the same funding sources or even types of resources. The fact that the Wall Street Journal, National Review, -and- this New Yorker article are all trying to make them so opposed, means if this line of thought is a method for causing delay, the hook was certainly bitten, which certainly will lead to useless argument and waste of time just as those opposed to any action will applaud.

    The quote from the National Review about how we can help the poor more by combatting these problems (poverty, disease, natural hazards) than by reducing CO_2 is REVOLTING to me, acting as if the writers of that journal had a meaningful program to do these things, what a straw man. On the other hand, reducing greenhouse gasses is certainly not going to impact poverty, disease and natural hazards like floods, storms and drought to such an extent that we will not have to deal with them and their effects on the vastly greater populations of today and tomorrow, even if there were magically no further change in the global warming. Yeah the resources we use to deal with disaster are definitely going to cut into our Green house gas reduction strategy. Wait what resources are we as a nation allocating to one now that could be used for the other?

    Personally my view, the only meaningful way to get serious about greenhouse gas reductions in the U.S. is by federal action, via regulation, taxes and active development and deployment policies, and only the last would have large costs at the government level. These would certainly put a cost on the economy in terms of higher fossil fuel cost, this may be a net reduction in cost as was shown in the 80’s when the US economy became more energy efficient as a result of higher energy costs, of course monolithic fossil energy producers would find their influence eroded unless they had the foresight to invest in some of the solutions. The new technolgy developed, the efficiency gained in the general economy, the flexibility against disasters from diverse and more efficient energy use, and finally the reduced risk of human induced large scale dislocation from human greenhouse gas emmissions are to me compelling arguments for an active greenhouse gas emissions policy, and better planning to reduce disaster damage ought to be part of that policy, not set up as a straw man against it. These are reasons we ought to be addressing that global dial and to be better prepared and with good resources and policy tough against weather related disasters is part of that strategy not an alternative.

    Pardon for the rant, but this fake radio button, choose one, good zoning and disaster planning or Greenhouse Gas reduction dichotomy grinds me.

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  11. Roger Pielke Jr. Says:


    There is no “excess of objectivity” here. I am aware of no scientific studies that indicate that GHG reductions can be a meaningful tool of disaster mitigation. In light of this, there is I suppose a consensus by proxy as the IPCC has not seen fit to take on this issue in its assessments.

    Dan Sarewitz and I wrote of this in The New Republic last year:

    “Those who justify the need for greenhouse gas reductions by exploiting the mounting
    human and economic toll of natural disasters worldwide are either ill-informed or

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  13. Dano Says:

    Markk wrote:

    “…the only meaningful way to get serious about greenhouse gas reductions in the U.S. is by federal action, via … active development and deployment policies…”

    You’ll likely enjoy this book then:



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  15. Steve Hemphill Says:

    “Excess of Objectivity”?? Sounds like an alarmist’s argument, to be sure. I’m not sure how increasing subjectivity (the opposite of objectivity?) or “religion” helps find a realistic answer. It certainly finds an “enemy” – which would be anyone who, say, owns a car…

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  17. Roger Pielke, Jr. Says:

    Steve- Apologies for the insider jargon, here is the reference:

    It is worth a read.

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  19. Steve Hemphill Says:


    That was an interesting piece, and I have to agree there is certainly no “excess of objectivity” here, unless one were to consider anthropogenic CO2 emissions as only potentially “bad.” The fact is, CO2 may be the closest thing we have on Earth to manna, and we may just be rescuing buried biospheric resources by retrieving oil. There’s a lot of desert on Earth – to just assume increasing the food supply for plants is a bad thing based on simplified models is, I would agree, either “ill-informed or dishonest”.

    Seems a gem at the end of a page pointed out by, I think, Andrew himself fits well when thinking about balancing good vs. bad as opposed to balancing nothing vs. bad, and is of late becoming my mantra. However, I’m not sure he gets it…
    “Feedbacks between atmospheric chemistry, climate, and the biosphere were not developed to the stage that they could be included in the projected numbers here. Failure to include such coupling is likely to lead to systematic errors and may substantially alter the projected increases in the major greenhouse gases.”

    Reading between the lines, it may also substantially alter the biospheric response of increased CO2, warmth, precipitation, etc.

    The fact is we just don’t know, and the dice are weighted against it just being “bad” – so before we go pinching off what could be a boon to mankind
    (as warming always has been in the past as well) we should find out what the consequences are to decreasing CO2 in the atmosphere – especially in taking (literally) “pains” to do it…