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Imprecision of the Phrase “Global Warming”

Filed under: — gavin @ 31 December 2004

Guest Contribution by Michael Tobis, University of Chicago

Consider the possibility that the expression “global warming” has become a problematic one, and that it might be best to avoid it.

A big part of the public confusion about climate change comes from sloppy language. The naysayers prey on this confusion, very much as their peers prey on the phrase “evolutionary theory” to suggest that “evolution, well, it’s just a theory”.

Scientists use “global warming” precisely, to mean “a tendency for the globe to warm over a given period”. Thus, in the question of human impacts, we discuss what proportion of the observed “global warming” in recent years is anthropogenic, what the magnitude of the “global warming” due to anticipated radiative forcing scenarios will be in the future, and the nature of climate change expected for a given “global warming”. In each case, we usually mean by this phrase precisely and only an increase in the mean global temperature.

I imagine I’m not alone in finding myself in a quandary when someone asks if I “believe in” global warming. Imagine asking an economist whether they “believe in” inflation. Where does one begin?

This problem arises from confusion (to some extent deliberately engendered) in the public as to what the term means.

If someone asks me in my capacity as a climate scientist whether I “believe in “global warming”, they are not asking the question in a literal sense. They are asking “what am I to make of this confusing topic called “global warming”?

In the end they are usually asking some combination of questions like 1) whether greenhouse gases are accumulating? 2) whether the greenhouse effect is established science? 3) whether global warming has been observed? 4) whether future climate change is expected to be big enough to worry about? 5) whether cooling at a single location falsifies the “theory”? 6) whether to expect super-hurricanes? 7) whether the Gulf Stream will shut down instantly glaciating Scandinavia and Britain? 8 ) how you can model climate when you can’t predict weather? etc. Often they will bounce incoherently from one to another of these sorts of exasperatingly-missing-the-point sorts of question.

Once in a while someone will have more sophisticated questions like 1) what’s the magnitude of the anthropogenic forcing compared to natural forcings? 2) what’s the lag time in the system response? 3) what is the magnitude of the most disruptive plausible scenarios? 4) what’s the likelihood of the discontinuous shifts in system regime? etc., When I hear people asking the right questions it makes my day, but it’s pretty rare.

What people outside the field universally don’t mean by “global warming” though, is “a tendency for the global mean surface temperature to increase”!

I believe that this site has made some progress by proposing a working definition of the scientific consensus.

Usually, when asked whether one “believes in” global warming, the best answer is to state that there is a scientific consensus and a formal process for developing it, and what that consensus is. For a sophisticated audience, one can go on to explain why consensus should drive policy and should not drive science, and what steps can be taken to ensure that this happens.

Still, the wrong questions are being asked and they are asked under a vague rubric of “global warming”. By allowing the focus to dwell on something that firstly means something different to us than to the questioner, and secondly that the questioner fundamentally finds confusing, we start on the wrong foot in our efforts to clarify these matters effectively.

Therefore I suggest to my colleagues that we avoid the phrase in public communication. We should be talking about “climate”, “climate forcing” and “climate change”, and about the “scientific consensus” and the “policy implications”. It might be wise, given the present confusion, to go so far as to publicly use expressions like “increasing average surface temperature” when we mean “global warming” in the literal sense.

To the public and the press, I suggest three things. First, define your terms carefully when talking to a scientist and tolerate the scientist’s insistence on doing so. Second, try to stick to one subject at a time. Finally, among the questions you should be asking scientists is “what are the most important questions?”

POSTSCRIPT: One of the RealClimate editors, Gavin Schmidt, pointed out in response to this submission that Richard Lindzen has also been exasperated by the question “do you believe in global warming?”.

It’s disconcerting to note that Lindzen, in thinking about this odd verbiage, quotes only misinformation of the alarmist type, though misinformation of the indifference type is at least as common and far more influential. That said, and without defending some other peculiar aspects of Lindzen’s expressed position, some of the similarities between his points and my arguments here are interesting. Perhaps he would agree that the phrase “global warming” has become too loaded with confusion and political baggage to be used effectively by scientists in public communication.

Michael Tobis PhD
Geophysical Sciences
University of Chicago

73 Responses to “Imprecision of the Phrase “Global Warming””

  1. 1
    David Russell says:

    I disagree that “global warming” is a problematic expression. The issue is knowing the distinction between three concepts: Greenhouse Effect, Climate Change, and Global Warming. Many people do not understand the differences between these terms.

    Global warming Theory is specifically the theory that anthropogenic sources of CO2 and other greenhouse gases are causing the Earth’s global temperature to increase. When the average non-scientist uses the term “Global Warming”, that is what they mean.

    However, many non-scientists also get confused and think that the Greenhouse Effect is Global Warming or that any reference to Climate Change is referring to global warming.

    In fact the job of climate researchers is to establish whether or not temperature records indicate warming. Then it has to be established how much of any warming is due to natural Climate Change and how much (if any) can be attributed to the effects expected from anthropogenic sources according to Global Warming Theory.

  2. 2
    Wil Burns says:

    The reference to Lindzen in the last paragraph will be confusing for the more general reader. I’d briefly outline his theory and then refute it.

  3. 3

    First, I was told, define your terms. Here is a start.

    Global warming is a term that is generally and widely used both within and outside the scientific world, to identify the theory that carbon dioxide produced by human activity, is acting to increase the surface and low atmosphere temperature of the Earth.

    A rational person would add, Carbon Dioxide is of course one of the many imperfectly understood factors, such as methane, water vapour, dust and organic particulates operating through a variety of chemical, physical, hydrodynamic and processes which affect the global climate both locally and worldwide.

  4. 4
    tom says:

    Although global warming may, at times, lack precision because of the differences in the intent of the questioner and the perception of the answerer, I think there is a danger in the use of the term “climate change” as well. This is the preferred terminology of the Bush administration because it sounds so benign precisely because it is even more imprecise that “global warming”. Climate change is a given and doesn’t precisely deal with the anthropogenic issues either.

  5. 5
    Randolph Fritz says:

    When commenting on the matter, I will generally protest that I prefer the term global climate change and don’t fuss beyond that. For discussions with the public, rather than scientific debate, “global warming” has the meaning, roughly, of human-caused global climate change as described by the IPCC and there seems no reason to be pedantic about it.

  6. 6
    pat says:

    This arrogant scientist sneers at the language of public discourse characterizing it as unsophisticated. In fact the public understands the issue and he doesn’t. People ask you if you believe in global warming because they have rightly perceived that this is an issue of belief. There is a technical aspect to the global warming debate but least relevant part of the global warming debate involves the climate science.

    People believe in ideas and ideologies for a number of well understood reasons. These include:

    Ontological comfort. Belief in life after death, Gaia, and a paternalistic God are all powerful concepts. We see just such a belief pattern in global warming believers who find in rising temperature data confirmation of mankind’s sins against nature. Alas much believe in the falsity of global warming is also faith based. Rush Limbaugh says in effect that man can’t cause climate change because the world is only subject to God’s will. No other scientific issue has so much religious belief at stake.

    Power interests People defend the Republican or Democrat parties as a way to promote poliical interests. Global warming has been promoted consistently by those who seek political advantage. Al Gore wrote in effect that he should be made global environment czar with trans national authority. He and Clinton have both used the Kyoto Treaty as a partisan issue in Presidential politics. Naturally most Republicans now respond to the global warming issue refelexively as an simply an undisguised partisan ploy. No other scientific issue has so much political power at stake.

    Monetary interests People will of course react to issues that involve sums of money differently from issues in which money is not involved. When you consider that the Kyoto Protocol would redistribute tens of billions of dollars, you should not be surprised that beliefs are influenced. No other scientific issue has so much money at stake.

    All of these issues swamp the climate science issues in relevance. When we argue about abortion we don’t expect recent findings about fetal development to be as relevant as is the belief in Roman Catholicism. We know that economists study the effects of litigation but we don’t expect their most recent findings to much impact on the Democratic Party both for questions of power and money.

    For better or worse, global warming is a spirtual, political, economic issue. In this arena climate scientists are only one kind of voice and hardly the most relevant.

  7. 7
    Peter Walling says:

    I would suggest you be very careful about changing the terminology at this stage of the game. The skeptics will be dishonest as ever and say the terminology was changed because of weakness in the science. It will not be true but it will happen. I can here the local news, climate scientists have back peddled on the term “Global Warming”.

    It also worries me that this is being discussed so soon after Buenos Aires where the Bush administration tried to change “climate change” to “climate variability”.

    The problem isn’t the terminology, the problem is the multi-nationals like Exxon/Mobil that are throwing huge amounts of money around to confuse the issue.

  8. 8
    mike says:

    I agree with Mr. Fritz…global climate change is a more accurate reperesentation. We know that the climate will change but will it be warmer or cooler? Data is far too limited to arrive at a defintive answer as to what will happen in the next few thousand years. It is easy to see the dichotomy that exists between those that believe that the earth will warm and those that believe that the earth will cool. Only time will yield the answers. From my own meteorological studies, there are too many variables – questions arise as to what type of forcings may occur from anthropogenic and natural changes to the global climate. We can only make educated guesses as to what will happen in the future but in the end they are only guesses…

  9. 9
    TM Lutas says:

    I don’t think that anybody reasonable out there denies that altering atmospheric composition is possible given enough of the right gases. In that trivial sense we all believe in the greenhouse theory as a valid theory. You just have to look at Venus for a bit to settle that issue. The question really is whether the current facts on Earth right now are something to worry about and worth doing anything in a public policy sense.

    In a similar sense, one can intelligently talk to economists about life without practical inflation. In fact, there’s an entire community of “hard money” advocates who favor its elimination and study periods where there was no such thing as inflation as money was a near constant store of value. Generally they’re called gold bugs. Famous gold bugs include Congressman Jack Kemp. Whether we’re in a hard money regime or a currency debasing regime is a useful set of questions for economists as inflation is only “useful” if it is a surprise.

    To “believe” in global warming is, in general terms for the layman, to say that we’re in a period where the human effects are both potentially and actually large enough to be more than static, the actual effects are tilted towards warming, and the consequences of these effects are negative. In other words, there’s something going on, we’re warming the planet, and it’s going to get us in trouble.

    The truth is that we don’t know when or how the next crisis will hit, the next category 9 quake with tsunami, the next asteroid, the next major shift that will stress humanity to its breaking point. All we know for sure is that the more resources we have stored up, the wealthier we are, the greater our chances of being able to survive, adapt, and overcome it. With global warming prevention strategies all seeming to take huge bites out of global economic growth, a global warming death toll has to be balanced against improving the economies of the third world to prevent all those other causes of death that would have to be foregone in a global warming prevention regime.

    I find the term is generally useful in a public policy sense, though it can be twisted by demagogues on both sides of the argument. Shifting terms will not improve things without other changes. Just ask the negro/colored/black/ people of color/ african-american and now black again whether the changing labels did them any good.

  10. 10

    Regarding Randolph Fritz’s suggestion that avoiding the phrase “global warming” is pedantic, I (unsurprisingly) disagree.

    The main point of my contribution was to make communication more effective. I have seen this difference in the use of the phrase “global warming” cause remarkable miscommunications between scientists and nonscientists.

    Getting the public to stop using “global warming” as a phrase representing the entire vast conceptual muddle of climate science and climate policy that they are currently beset with is unfortunately not a realistic goal in the near term. What is realistic is to urge the scientific community to understand first that the important and precise concept that they refer to as “global warming” has no name in the public understanding, and second that when non-specialists use the phrase they generally are talking about a much broader subject, usually with a lot of ill-conceived notional and emotional baggage.

    One way for scientists to begin clearing the muddle is by noticing and if possible avoiding phrases that are dreadfully confused and emotionally charged in public usage.

    This may indeed have the appearance of pedantry or even evasiveness, but it’s nothing of the sort. It is exercised only in the interests of disentangling the muddle, which is, after all, what this site is for. Thus my plea to tolerate the scientist’s insistence on a clear definition of terms.

  11. 11
    Steve Bloom says:

    Way back when I took basic physics, I don’t recall the term “warm” being used other than informally to refer to an arbitrarily lesser amount of heat. Warmth just plain has entirely positive linguistic associations — think “warm and …” I suspect that for most people “cuddly” comes to mind, with “cozy” a close second. Was “global warming” coined by a scientist (maybe someone knows about this), but at a time when whoever that was thought that the effect was likely so subtle that “heating” just seemed like too strong of a term, and any conclusions as to possible outcomes (as implied by something like “disruption”) would have seemed like too big of a step?

    Since it’s probably too late to get rid of “global warming” absent a concerted long-term effort to do so, I suggest switching to a phrase like “climate disruption” that will have the effect of shifting public discourse in the right direction even while “global warming” remains in use. “Forcing” would actually be better than disruption in the technical sense, but has the problem of itself needing explanation. “Change” has the same positive association problem that warmth does, and as someone pointed out the Bush regime would love it if we went that way. People understand what disruption means (although it does have the drawback of having three syllables). “Human-driven climate disruption” would actually be better, and would perhaps be best for both scientists and activists to use even if the press will tend to knock it down to just plain “climate disruption” in many instances.

  12. 12

    Edward Taegue alleges that:

    Global warming is a term that is generally and widely used both within and outside the scientific world, to identify the theory that carbon dioxide produced by human activity, is acting to increase the surface and low atmosphere temperature of the Earth.

    This is incorrect. While this definition lies well within the spectrum of common usage, in scientific discourse the term global warming refers to a tendency for the mean surface tempreature of the planet to increase over a given period. As such, it is not limited to the contemporary situation nor to greenhouse gas forcings.

    He also states that:

    Carbon Dioxide is of course one of the many imperfectly understood factors, such as methane, water vapour, dust and organic particulates operating through a variety of chemical, physical, hydrodynamic and processes which affect the global climate both locally and worldwide.

    In this he makes an assertion that is uncontroversial. Its purpose appears to me to be polemical rather than discursive.

    The term “imperfectly understood”, while correct, slyly implies to the casual reader that existing knowledge is insufficient to draw any meaningful conclusions about whether “carbon dioxide produced by human activity, is acting to increase the surface and low atmosphere temperature of the Earth “. Of course, this does not follow.

  13. 13
    jean paul pinzuti says:

    lets keep it simple: how is it possible to argue AGAINST the fact that an ever increasing number of internal combustion engines and other carbon dioxide emitting devices increase the risk of ACCUMULATION in our atmosphere ??? and that such an ACCUMULATION is bound to have an effect on air pollution and climate ??
    this is especially true in developping countries megapoles: have the “nay sayers” ever visited: bombay, calcutta, cairo, jakarta, mexico city, shangai …???
    incomprehensible “jargon” is a time tested method by every “old guard” protecting their turf: be it in business, education, heath-care, law, politics etc… so forget the jargon and listen to time tested “common sense”…regards

  14. 14
    David Russell says:

    There is no “danger” in the use of “climate change” unless your goal is to confuse people into thinking that any climate change must be the result of anthropogenic sources. In order to understand what is happening now, it is absolutely necessary to look at what climate has done in the past … before the industrial revolution. And any discussion of climate evidence prior to the industrial revolution is “climate change” not “Global Warming”.

    In addition, you cannot simply say that once the industrial revolution begins we need only use the term “Global Warming”. To take such a position implies that the natural climate forcers can now be ignored. How much of any warming the last 100 years is natural climate change? There have been warming and cooling trends in the last 150 years. If it is credible to claim that CO2 is an important climate forcer, then it must be acknowledged that the 1940-1970 cooling trend had some other cause. Perhaps industrial pollutants contributed, but almost certainly natural forcers such as solar variations were behind the cooling. It is well established that sunspot cycle length correlates with the temperature anomaly during the last 140 years. As such, “climate change” in the last 150 years is still relevant.

    I have to disagree with Michael Tobis on the use of “global warming” in reference to any condition of rising planetary temperatures. “Global Warming Theory” posits that humans are causing an increase in average planetary temperatures through increasing greenhouse gas concentrations. Natural warming cycles fall under the category of “climate change”. The planet cools and falls into ice ages. Then it warms and pops back out. Such warmings and coolings are “climate change” and discourse should not be muddled by referring to such events as “global warming” or “global cooling”.

  15. 15

    I agree with Steve Bloom that “human-driven climate disruption” or “climate disruption” for short is a better name for the cluster of concepts that is currently called “global warming”. I’d appreciate such a shift in the press but don’t expect it. Realistically, the scientific community needs to understand the public’s overloading of the phrase “global warming”, and the public needs to understand the scientist’s aversion to using imprecise phrases.

    I think that William Connolley’s summary of the consensus position provides us with a very useful way to disentangle the confusion. Let me try to put names to the parts of it:

    • The detection hypothesis The earth is getting warmer (0.6 +/- 0.2 oC in the past century; 0.1 oC/decade over the last 30 years
    • The attribution hypothesis People are causing this
    • Global warming prediction hypothesis If GHG emissions continue, the warming will continue and indeed accelerate
    • Climate change cost/benefit hypothesis This will be a problem and we ought to do something about it.

    One way to define “global warming hypothesis” is the union of all four of the above, and another is the union of the first three. Teague and Russell assert confidently that the “global warming theory” (presumably ‘theory’ means ‘hypothesis’ here) is the union merely of the first two points only. By that definition, the “global warming theory” is demonstrably vastly more likely to be true than false.

  16. 16
    David Ball says:

    It’s interesting to read the comments here so far. They represent, to a certain extent, a microcosm of those one sees from the public. I happen to share Michael Tobis’ view, which will no doubt appall him ;-), that the term is imprecise, though perhaps for a slightly different reason. When we limit discussion to the term “global warming”, I’m not sure that the public understands the scope of the problem. So what if the temperature goes up by a degree globally? It’s the “so what” that IS the problem and it is the various so-whats that need to be described to the public. By creating an environment where the global temperature is increasing we are changing the weather and therefore the climate and it is those changes, possibly rapid changes, that are the concern. Climate doesn’t kill people. It doesn’t destroy their crops. Weather, or the lack of it, does and the public has to understand that through our GHG emissions we altering the weather on a global scale. Given that, I’m not sure that “global climate change” is even appropriate, because climate is not a static thing. It changes all the time and does not require a human component to do so. Perhaps what is needed is a two-fold statement, one highlighting the linkage between weather and climate, because I’m not sure that the distinction is clear to the public and secondly a statement about it being human-caused. Anthropogenic is the term of choice right now, but try using it in a group of non-scientists and you are likely to see a lot of confusion about what is being discussed.

  17. 17
    TM Lutas says:

    Re comment # 13, it is quite easy to argue that the balancing factors in the worldwide climate system that have ensured we have not slipped into a runaway greenhouse effect (see: atmosphere of Venus) are robust and are able to handle orders of magnitude higher human greenhouse gas contributions to the system before we have to worry. This doesn’t mean that the argument is right or wrong but the idea that such things are a prior decided without the messy necessity of research and gathering evidence proving such assertions is antithetical to science and belongs with the Michael Moore and Ann Coulter mindset.

    I count myself a skeptic that the case has been proven for global warming sufficient to engage in the human destruction that will ensue from pulling that much growth out of the global economic system. The cost of delaying or denying economic growth can often be hidden and very often it is. Only with a political collapse, such as 1989 E. Europe or a natural disaster such as today’s Indian Ocean basin that you end up undeniably staring the consequences in the face.

    Even granting the most optimistic of assertions of our state of knowledge of the climate end of things, the utilitarian balancing test that must be done for proper public policy is undoable without a very good understanding of the economic end of the equation. Where is the human misery minimum point? Is it in doing nothing, concentrating on mitigation of any effects as they crop up or in a major prevention campaign?

    The major disadvantage of a prevention campaign is that you have to decide early, decide big, and it seems to extract the largest price tag in increased human suffering elsewhere, concentrating that suffering most on the poorest among us. For most people, that creates a very steep evidentiary requirement that can’t be met by the style of hand waving evidenced in comment #13.

    Unfortunately, I don’t think that the optimists on the state of our climate knowledge are right. I think that there is quite a bit left to learn about how this planet works. I strongly suspect that there are enough holes left in our knowledge that the optimists are very much engaging in politics and not science when they make categorical statements.

  18. 18
    garaud says:

    A quand une traduction francaise de ce site qui m’intéresse beaucoup ?

    Réponse: Malheursement, nous avons ni le temps ni la competence de faire les traductions en temps reel. Si on trouvera des colleagues francophone qui veut nous joindre, on peut visiter la question de nouveau. On s’excuse! – gavin

  19. 19
    George Roman says:

    It seems that the terms ‘global warming’ and “climate change” are both easy targets for skeptics who want to emphasize the natural variability of climate, while downplaying the role of anthropogenic forcing. Perhaps scientists should insist on clearly communicating more precise scientific terms to the media and the public, such as ‘enhanced greenhouse effect’, ‘changes to atmospheric composition’, ‘climate disruption’, and ‘human climate forcing’. These terms are more precise, less controversial, and less politicized than either “global warming” or “climate change”.

  20. 20
    Bucky says:

    Global fever.
    People in temperate latitudes associate being warm with comfort. A warm day is a nice day, and in winter keeping warm is vital. Warmth in an emotional sense is a positive state – friendly, loving, open-hearted.
    It may be scientifically accurate in measurement terms, and it was probably necessary twenty years ago when I first heard it used, to get the concept itself into the public dialog – but as a descriptor for lay people it’s misleading, it isn’t accurate at all.
    Fever is.

  21. 21
    dave says:

    I do think it is important to find good terms and arguments for explaining climate change to people who know nothing about it.

    I asked a professional (psychologist) friend – is the term “global warming” loaded? She thought about it for a bit and said “yes”. She thought the term carried many hidden meanings, all of which basically boil down to “threatening to people”. It’s probably not a good term for this reason alone – it scares people and when people are frightened, they are not amenable to argument and rational thought, to say the least. In fact, people are then almost invariably prone to psychological defense (denial, rationalization, And this kind of defense is even more understandable when we consider all the benefits that an economy based on fossil fuels has conferred on people – at least up to now. And since a solution moving away from fossil fuels seems so insurmountable, people will be defensive anyway. Tough problem.

    I’ll submit the climate model term climate sensitivity. This leads to a further question – sensitivity to what? To which you can answer, sensitivity (or climate response) to a doubling (or more) of CO2 in the atmosphere. This leads to the question – why should more CO2 make a difference? To which you can answer, CO2 in the atmosphere absorbs and re-radiates infared heat radiation (thus acting like the glass in a greenhouse, just like the inside of your car on a hot day when the windows are all rolled-up). Etc.

    An aside Re: #7, I didn’t know about the Bush administration attempt to introduce the term “climate variability”. Now that’s scary.

  22. 22
    Pat Neuman says:

    I use “climate change” when talking about regions…
    … as in “climate change is in progress in the Upper Midwest….
    My paper on earlier snowmelt runoff and increasing dewpoints
    for river basins in the Upper Midwest and northern Great Plains
    shows that to be happening…
    my paper is at

    I use “rapid global warming” to indicate the global warming that
    is happening now is or will be too rapid for many species to adapt to.

    I think “global climate change” is ok to use. I don’t like it when
    some think “global warming” is just temperatures. Global warming and
    climate change must also identify “hydrologic change”. Hydrology is
    an essential ingredient of climate that must not be overlooked because
    water is essential for life and can also cause much destruction and
    death as we’ve just witnessed with the Tsunami.

    Pat N

  23. 23
    RD Alward says:

    In comments #9 & 17, TM Lutas alleges, without evidence, that addressing the potential consequences of elevated-global-average-surface-temperatures (for lack of a better term!!!) will lead to unacceptably negative economic consequences.

    I am unable to follow the argument. Given the uncertainty of the ecological consequences, not to mention the climate consequences, it seems quite far fetched to argue as if it is known that the economic consequences would necessarily be negative. Indeed, I would hazard the argument that addressing the human causes of increasing concentrations of radiatively active gases in the atmosphere would more likely contribute positively to the economy (at local, regional, national, and global scales).

    Afterall, who designs, builds, installs, and maintains more efficient devices? Answer: People with jobs, of course.

    Who designs, builds, installs, and maintains devices that generate energy from renewable resources? Answer: People with jobs, of course.

    Who transports, imports, exports, and sells these devices? Answer: People with jobs, of course.

    Thus, there is no reason to assume that reducing reliance upon technologies that add CO2 and other gases to our atmosphere will necessarily lead to economic disruption. Additionally, a concern about potential economic change in no way alters the scientific evidence pointing to a detectable anthropogenic role in future climate change.

    In other words, the tactic of dismissing the science regarding the magnitude of potential social and ecological (and even economic) consequences associated with a human-induced enhanced greenhouse effect (or other term suggested above!) by economic fear-mongering just doesn’t wash.

    [My apologies for this digression focusing primarily on economics, rather than science, however I felt it was important that TM Lutas’s claims receive at least a bit of comment.] Carry on with this wonderful service …

  24. 24
    Alec Melvin says:

    Richard Lindzen’s comments on global warming and carbon dioxide are very apposite. It is a matter of spectroscopic fact that the infra-red absorption bands for CO2 are currently saturated in the first 50 metres of the troposphere. If the Chinese expand their car population to 30 million and add considerably more CO2 to the atmosphere, there would be no additional contribution to global warming by CO2. Moreover, if the Kyoto enthusiasts succeed in reducing CO2 emissions by 60%, the Lambert-Beer law tells us that saturation will occur in the first 100 plus metres and global warming will not be reversed. It is clear that climate change if it does occur must be linked to changing water vapour distributions over the planetary atmosphere and we need to ditch the red herring of CO2 (apologies for the metaphor foul-up!) if we seriously wish to understand the behaviour of our climate.

  25. 25
    John Bolduc says:

    I don’t think that the debate over what term to apply to the general problem is all that important. If one were to find the “perfect” term to apply, I don’t think it would change the situation very much in terms of governments and people taking action. It seems, based on polling and daily experience, that there is a general acceptance among the public that climate change/global warming is happening already.

    I believe that the missing piece is that there is not a general sense that the problem is urgent. I think this is true even among many, if not most, declared environmentalists. Obviously the urgency of the problem is a point of great debate and the scientific thinking appears to range more signficantly. However, when I as a layperson look at the scenarios presented by the IPCC and others about when we have to start reducing GHGs to stablize atmospheric concentrations in the 450 to 500 ppm range, and thereby minimizing warming and the related consequences, it appears to me that we have to have started already to significantly replace fossil fuels with effiency and non-fossil sources of energy.

    Wouldn’t it make more sense to concentrate on educating decisionmakers and the public about the nature of the problem and solutions? There is some interesting work that suggests there is very poor understanding of the stocks and flows nature of GHGs and the timing issues involved. See John Sterman’s “Cloudy Skies: Assessing Public Understanding of Global Warming” article ( I’m not sure, even a little cynical, that this would make a difference. But one of the things we know for sure is that the concentration of GHG’s is increasing.

  26. 26
    kyan gadac says:

    Most of this thread is garbage! There is nothing imprecise about the term global warming. You either accept the basic sceince that increasing greenhouse gases such as CO2 is gong to warm the planet, or you don’t. If you don’t then you’re either an idiot or in the pay of someone whose an idiot. Sorry to blunt but I’m Australian.

    This whole topic is pandering to idiots – call a spade a spade and if they want to play pedantic little games because they don’t understand or don’t want to understand basic science and commonsense, then call it like it is – they’re idiots and nothing you can say will change that fact.

  27. 27
    Jeffrey Davis says:

    The language of the public debate should be, where possible, the language of the scientific literature. The loss of ambiguity would do much to defuse the flummery of so-called skeptics. Let the scientists sort it out and take the lead here. Journalists and others writing for public consumption should follow.

  28. 28
    Kevin T. Kilty says:

    I hesitate to join this discussion, but it has irritated me beyond all reason, so I must.

    Science involves skepticism. Certainly some skeptics are ignorant, but a large number are not, and if you cannot tolerate dissenting opinion without labelling the beholder of such an idiot, stooge, or fellow traveler of intelligent designists, then please drop the pretense of being a scientist and join a religious order or a political party. Even a plain spoken Aussie should accept this.

    Why berate the general public for their misunderstanding of this subject, and then propose to solve the problem by adding a thick layer of pedantic verbiage? This will not increase precision one iota. Besides, scientists should be cautious about berating everone else for ignorance when the scientists misapply statistics to this issue so badly themselves.

    The general public probably understand the whole issue better than we scientists think, and they have a good gut feeling for linkage of the issue to the economy, or at least to that portion of the economy that affects them directly. You will not lower concentrations of GHGs without economic dislocations that affect the majority of the general public. Stop trying to fool them with the idea that all this change will pay for itself.

    Next, I do not see what is so “missing-the-point” about the hierarchy of questions that exasperate Michael Tobis. They appear to parallel the hierarchy of concerns any reasonable lay person, or scientist for that matter, should express about a scientific issue. And by answering them Tobis would illuminate exactly what we know without any doubt, and what issues are highly uncertain. What is so missing-the-point about wondering if hurricanes will become stronger or more frequent? Any person who pays for insurance, pay taxes, or has assets in the subtropics should ask such a question. It is absolutely to the point; albeit a bit narrow of scope. The problem seems to me that scientists do not like to address such questions because they often have to say, “We don’t know,” and this makes science appear a bit irrelevant. However, acting in a smug and condescending manner toward the public does science no good either.

    Finally, while it is true that people who work on ideas, technologies, and products all contribute toward the economy, one has to worry about funding horrific boondoggles, and pursuing unhelpful ideas. Not all change pays for itself. The dotcom fiasco of the late 1990s should be a cautionary tale about good money chasing bad ideas involving technologies. It takes time to replace the investment capital lost in such “bubbles.” Our present quandary is that fossil fuels are marvel-sources of portable, flexible energy. It is going to be a long effort to find viable alternatives for all purposes.

  29. 29
    jim brogli says:

    Theory…A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.

    Whether you think the kinks have been worked out of evolutionary “theory” or not, it is, by definition, a theory. There are many prominent scientist(evolutionary biologist, physicists etc.) that point to many undetermined and unresolved issues in this theory as there are many undetermined and unresolved issues in global warming. Hopefully, as you endeavor in your science, you will not see your destination while your map is incomplete. Global warming and evolution are obviously very pertinent, but dogma applied to any theory, philosophy etc. only serves to repress an open exchange of ideas, which ultimately only serves to create discord. Scientists should be careful not to go the way of the journalist and become irrelevant in the eyes of the public, who truly need them to see the world as it is, not the way one would wish it to be.

  30. 30
    dave says:

    Re #24: I do not understand this post about an argument by Lindzen nor can I find a good reference on the internet that explains what is meant here.

    Could someone tell me what this is supposed to mean? Nobody responded to it and I don’t know what that means. Not worth discussing? or not? I assume this is unrelated to the Iris Hypothesis concerning clouds and water vapor feedback. So, what is this (gavin? eric?)

  31. 31
    Pat N says:

    I find it confusing that the NWS Climate Prediction Center issues
    “climate” outlooks which have nothing to do with the subject of
    climate change or global warming.

    The NOAA NWS strategic plans use “Climate variability and Change”,
    which I find tob be confusing, even misleading at times. This is a
    major federal agency with direct ties to local and national media,
    local and state agencies, other federal agencies, and businesses
    world wide. NOAA, NWS have the machinery to educate the public
    about global waming. Why isn’t this working like it should?

    [Comment #42 under “Will Full-Ignorance” seemed pertinent here, thus
    the relevant part is repeated above.]

    Pat N

  32. 32
    Ethan Vishniac says:

    I find comment #24 confusing. Increasing the optical depth of the atmosphere affects the
    temperature even if the optical is already greater than one, even if it is much greater than
    one. This is based on a static radiative model for the atmosphere (I’m an astrophysicist)
    so it’s bound to be simplistic, but I think it addresses comment #24. Lindzen must
    be misquoted here, or something. I understand he’s a controversial figure here, but I
    enjoyed taking Applied Math 1 from him many years ago and I can’t believe he’d say
    something so clearly wrong.

  33. 33
    Dave says:

    Where is George Lakoff when you need him to comment?

    I would argue that the ultimate goal of any climate change discussion is reducing greenhouse gas emissions. Inspiring people to action, influencing policy, and raising public awareness are far more important to that end than the precision of scientific terminology. While I would agree that it is essential to ground any discussion of climate change in sound science, it is equally, if not more important, to frame the debate in a manner which inspires people to care. So phrases like “climate forcing” and “anthropomorphic climate change”, while accurate, lack the emotional gusto to raise any eyebrows. In fact, many people from the general public won’t even understand these terms. In the case of people that don’t understand or aren’t interested in the discussion because of the terminology used, the scientific community will have failed in reducing greenhouse gas emissions, despite using precise language.

    I am not asking scientists to take on the role of journalists or advocates; this is a slippery slope. However, the language scientists use to frame the debate influences public opinion, by default, by its very “sex appeal” for lack of a better term. Therefore, scientists have a responsibility to choose terms carefully, not for the sake of scientific precision as Dr. Tobis argues, but for the sake of emotional impact. The purposeful avoidance of politically or emotionally charged terms, instead opting for neutered, scientifically precise terms, is just as slanted as the journalist, advocate or politician because of the way language defines a discussion.

    My vote is for climate disruption or climate crisis, neither of which confuse the scientific discussion. Climate crisis, in particular, stays true to the sense of urgency required to address this largely uncertain phenomenon.

  34. 34

    Mr. Kilty suggests that the general public is being berated for their misunderstanding of the issue. I do not think that is the case. There is general confusion, and the fault belongs jointly to the scientific community, the press, and those who deliberately obfuscate these matters. This site is an effort to improve the contribution by the scientific community to the discussion, largely by facing the disinformation rather than pretending it doesn’t exist.

    Mr. Kilty suggests that scientists misapply statistics badly. This seems to me surely a gross overgeneralization, but I don’t know specifically what he means by this.

    Mr. Kilty suggests that someone is trying to “fool the public” that the economic changes required by these issues will “pay for itself”. This is certainly off topic for this thread, and probably for the entire website. For what it’s worth, I don’t feel that the carbon constraints will “pay for themselves” in the absence of environmental impacts, but that has little to do with the purposes of my article, nor, as I understand it, of this site.

    Mr. Kilty suggests that the scientific community is loathe to admit uncertainty in any particular matter. There is a grain of truth to this, because the obfuscators take the slightest admission of uncertainty and elaborate it into a cloud of doubt over the entire sphere of interest. That said, my litany of questions was intended to indicate to the scientist, for whom “global warming” constitutes a number (typically expressed as degrees Kelvin per decade), the array of issues that are hiding in the phrase as commonly used. My point was simply to prevent a common source of misunderstanding between scientists and the public.

    I believe this site has already addressed many of these questions and will continue to try to address them one at a time. However, I feel that any question misses the point that does not address the enormous magnitude of global change that appears increasingly likely as vigorous policy action continues to be delayed by decades.

    Mr. Kelly’s concluding paragraph is something I mostly agree with, as I would venture most of the contributors here do. I would note, though, that in his response he refers to the “portability” of fossil fuels, which seems to refer to their use in vehicles. Many other comments here seem very focused on vehicular use of fossil fuels. In fact, vehicular use of fossil fuels constitute a rather small part of the emissions burden, and the bulk of the risk in the future comes from coal-burning power plants. These are not trivial to replace, but are prehaps easier to address than internal combustion engines.

  35. 35

    As others have pointed out, Alec Melvin’s confident assertion that he has found an elementary error in the proposition that increasing CO2 can cause increasing surface temperatures, despite the generally held opinion in the geophysical sciences, is incorrect.

    Among the many ways to disprove Melvin’s idea, perhaps the clearest is to refer to the surface temperature of Venus, which if here were correct, would be inexplicable.

    Melvin’s idea should not be attributed to Lindzen, who never said anything of the sort.

  36. 36
    dave says:

    Can we get back to the science, please? Let’s not get lost in semantics and the meaning of the term “global warming”. The Earth’s climate is warming. What do the climate models say? The natural forcings show a slight cooling. Therefore, the correct answer to “how much of this warming is due to human influences” is, as noted in another post, more than 100% of it.

    I (comment #30) and then another poster (#32) responded to a very confusing comment regarding some Lindzen theory about saturation of pC02 in the lower troposphere:

    It is a matter of spectroscopic fact that the infra-red absorption bands for CO2 are currently saturated in the first 50 metres of the troposphere. If the Chinese expand their car population to 30 million and add considerably more CO2 to the atmosphere, there would be no additional contribution to global warming by CO2.

    Nobody has responded. Why are we arguing about these terms? I say this as a former theoretical linguist who taught undergraduate level courses in advanced logics, semantics and formal language theory (many years ago). Now, people are mentioning George Lakoff in their posts. This could not be more irrelevant to climate science. C’mon, let’s get away from this.

    I would much rather hear about advances in climate modeling, our understanding of the carbon cycle and the possibilities involving abrupt climate change, not to mention a number of other subjects of interest.

    And by the way, Michael Tobis, I got a B.A. University of Chicago, 1975 – just to establish some common ground here.

    Let’s get real.

  37. 37
    Pat N says:

    Michael Tobis wrote: (#34)
    > Mr. Kilty suggests that the general public is being berated
    > for their misunderstanding of the issue. I do not think that
    > is the case. There is general confusion, and the fault belongs
    > jointly to the scientific community, the press, and those who
    > deliberately obfuscate these matters.

    I think people have a responsibility to learn what’s going on.
    They need to know where to go to for advice about regional climate
    change and global climate change / global warming. I think NOAA’s
    National Weather Service(NWS), with their many local offices and
    direct ties to media and local govs, need to start educating the
    public on climate change. The local NWS meteorologists and
    hydrologists could be having face to face discussions with
    highschools, with the public at local libraries and with local
    government employees at city, county and state offices. I think
    doing that would be a great public service. Why isn’t it being done?
    … two reasons … 1) NOAA Administrators and NWS directors have
    not allowed their staffs to talk with the public about global warming.
    The Administrators and directors are saying that global warming is
    too political or too controversial to allow their staffs to discuss
    it with the media or public. Those employees that choose to speak
    out about global warming happening risk loosing there jobs. 2) The
    majority of meteolorologists in the U.S. have been and still are
    SKEPTICS on global warming. Many don’t understand that global
    warming is happening and they haven’t taken the time to investigate
    nd see that it is.

    Another group that could help are the State climatologists. Most
    are members of the American Association of State Climatologists(AASC).
    State climatologists have a primary background in meteorology and
    archiving of meteorological data for the periods of record (most
    from 1890-current), but their knowledge of paleoclimates and the
    disciplines involved in climate other than weather atmosphere is
    limited. For example… they know little about hydrology, arctic sea
    ice, vegetation and transpiration processes, etc. Yet, because their
    title includes climate, the public perceives these “climatalogists”
    and meteorologists as good sources for information climate
    change/global warming, but they are truly lacking in that, in general.
    However, they convey the skeptic views on global warming to the media,
    local governments and other… usually off the record on an informal
    basis. Tax payer funded meteorologists and mislabled climatologists
    should not be telling the public that there is no global warming
    problem… but in fact many of them have been doing that for many
    years already. When will that stop?

    Some of this is at another post (see thread titled:
    “Will-full Ignorance”,… beginning with “Dano” …

    Pat N

  38. 38
    dave says:

    OK, I just saw your comment #35 re: the Melvin post #24. As you said, Lindzen never said anything like this. Which partially explains why I could not find any information about it on the web and eases my frustration about why there was no response to it. However, with respect to your response

    >>As others have pointed out…

    In all cases like this, a web link to further information would be helpful.

    Also, there is no end to delusional, unsubstantiated, psychologically or politically motivated arguments against the on-going reality of climate change (warming). Thanks for that post.

    Have a good one.

  39. 39
    TM Lutas says:

    I won’t bore you all with too much economics but the idea expressed in comment #23 that adding government regulation to force less CO2 and other greenhouse gas emissions deserves at least one example to demonstrate the capital destroying effect of such initiatives. It may surprise some here to find out that when a US company is through with its machines, they don’t automatically go to the scrap yard for recycling. Very often, a machine, an entire production line, even an entire factory can be sold for far more than its scrap value to someone else, often in the third world, who will happily continue to use the equipment for many years more.

    Such sales are anticipated from the moment of purchase. Obviously, a factory whose equipment is too polluting to continue operations profitably must be closed down and replaced but the old equipment can no longer be sold. That’s destruction of capital, just one example, and there will be many, many more in a real global warming control regime.

    Comment #26 is of interest. I’m pretty sure that it’s accepted science that the climate is a complex combination of factors some of which tend to warm and others cool the planet. The end resulting climate is a balance of the factors with all sorts of feedback loops that ensure that when the solar cycle or other extra-planetary events cause a hiccup, the whole system doesn’t spin out of control, searing (or freezing) life away. Global warming is not, contrary to kayan gadac’s assertion, whether there are factors like CO2 that warm the planet. Obviously they do that, otherwise we’d freeze. Rather global warming is an assertion that the cooling factors are unable to adjust to human contribution to the warming factors, something that I think is much less certain because you’re talking about the interaction of several systems. Furthermore, it’s not clear to me whether the solution is to stop contributing to warming or, instead, to increase our contribution to global cooling.

    Comment #33 is, frankly, dangerous to true science. While I would be the last person on the planet to say that there is no place for advocacy, it’s poisonous to assert (and to permit the assertion without challenge as well) that all discussion must be advocacy. The ultimate goal of science is to discover the truth about the universe around us, to the extent that it can be discerned using the scientific method. If the “ultimate goal of climate change discussion” is advocacy, climate change discussion simply isn’t science and you should all turn your grants back in if they were obtained with the expectation that science should result.

    I think that global climate change is, or at least can be, valid science. Assertions that it ultimately is advocacy in every case should be offensive to any scientist no matter what your position is on the question of global climate change. Defend science as science! The facts will be discovered and solutions will be found but you lose your influence if you lose your objectivity. Don’t let it happen.

  40. 40
    FxsI says:


    I think that William Connolley’s summary of the consensus position provides us with a very useful way to disentangle the confusion. Let me try to put names to the parts of it:

    1. The detection hypothesis: The earth is getting warmer (0.6 +/- 0.2 oC in the past century; 0.1 °C/decade over the last 30 years.

    2. The attribution hypothesis: People are causing this
    Global warming.

    3. Prediction hypothesis: If GHG emissions continue, the warming will continue and indeed accelerate.

    4: Climate change cost/benefit hypothesis: This will be a problem and we ought to do something about it.

    One way to define “global warming hypothesis” is the union of all four of the above, and another is the union of the first three.


  41. 41
    Dlwer says:

    A quick side note on TM Lutas comment’s and those interested in the economics of climate change:

    There is quite a bit of economic research being done on climate change, efficient emission path’s etc. For a start look a Nordhaus’ RICE and DICE models, but there is plenty more in the various journals.

    Obviously this is NOT the topic of this blog, but I thought it might be good to point out that research on the economics of climate change is happening as well for those interested.

  42. 42
    kyan gadac says:

    Still a lot of idiots – look, the problem is not the scientists and not the general public. We can see global warming happening with our eyes, we can see satellite pictures of vast brown clouds of pollution over the Asian sub-continent, we can see rainfall dropping in temperate Australia and be wondering where the water for the cities is going to come from in 5 years time. We can see animals abandoning habitat and changing migration patterns across the world, we can see glacies and snow lines retreating and we can see, if we’re bothered, the hard statistics of the actuaries.

    No the problem is the coroner’s problem – is this negligence, wilful or is it just stupidity. Are these people lying or are just incapable of understanding what everybody else can understand. I’d say to these so-called skeptics stand up and be counted tell us who’se paying you to be such idiots.

  43. 43
    Bruce Marshall says:

    Re Comment 34, ” In fact, vehicular use of fossil fuels constitute a rather small part of the emissions burden, and the bulk of the risk in the future comes from coal-burning power plants.”–whatever the future, here are some numbers for the recent past:

    in 2002 31% of GHG from fossil fuel combustion came from the transportation sector [=petroleum], 40% from electrical generation, 17% from industry, according to the Executive Summary, U.S. GHG Emissions and Sinks, 1990-2002, Table ES-4.

    in 2002 43% of GHG from fossil fuel combustion came from petroleum {31% from petroleum used for transportation}, 36% from coal, 21% from natural gas, according to the same source, Table 3-3.

    I developed the percentages I give from numbers given in the above source.

  44. 44
    Dave says:

    TM Lutas, I just wanted to respond to your comments about my post, #33.

    I believe that I misrepresented myself in saying that all climate science discussions should aim at reducing greenhouse gas emissions. What I really meant is that all sound scientific discourse about climate change has concluded that humans should curb greenhouse gas emissions or face the consequences of a rapidly changing climate. I think there is a subtle but discernable difference.

    However, I stand by my assertion that the language used to frame the discussion of climate change affects the way the subject is understood and acted upon.

    Normally, I wouldn’t even respond to a discussion of terminology as it relates to scientific discourse among peers however, Dr. Tobis clearly stated that scientists should mind the terminology the use when addressing the general public and media, which requires a different responsibility. The terminology used to describe climate change to the general public will affect how the subject is understood or its perceived relevance. I’m not saying scientists should be advocates, but I am saying that they are, by default, framing the discussion through the language that they use. Precise scientific terminology (what I percieve to be stale) will elicit an and emotional response whether that was the scientist’s intention or not, albeit a response that is perhaps muted or disinterested, unlike the response to a term like “global warming.”

    Perhaps it is only the scientist’s job to be precise, and true to the science. But in this purist scenario, it wouldn’t really be the scientist’s job to frame the debate in the media and to the public. In reality however, scientists do coin the terminology and frame the debate, and with that comes a responsibility.

  45. 45

    In response to Dave’s # 38, by “others pointing out” the problem with Melvin’s postings, I simply meant himself and Mr Vishniac on this list. I had never heard this allegation before and don’t expect to run across it again.

    Melvin hasn’t got much of a footprint on Google, but the citation index shows someone by that name as an expert on natural gas production and combustion. I didn’t see anything on radiative transfer. As a guess as to where his error arises, perhaps reradiation is not important in the processes he studies. It’s critical in establishing radiative equilibrium in an atmospheric column.

  46. 46
    Kevin T. Kilty says:

    Back to comment #34 for a moment. The contribution of vehicles to the accumulation of CO2 in the atmosphere is not a negligible concern. Something like 40% or more of the emmissions are from transportation sourses. Now if you think that CO2 concentration can be stabilized by ignoring this, and the Earth could find a way to just absorb that 40% contribution, then fine–get rid of all other uses of fossil fuels, but keep gasoline, diesel, JP-4, etc for transportation. However, I doubt this is possible, so to prevent the abandonment of fossil fuels causing a huge dislocation in transportation, which will produce a huge disloaction in both commerce and manufacturing, then we must find a viable alternative PORTABLE, and flexible source of energy. The pertinent question is perhaps: how much more CO2 can the atmosphere handle while we find this alternative? What are the risks? What are the likely consequences? Please correct me if I am wrong, but you, Mr. Tobias, appear to be irritated by the public and skeptics asking such questions in awkward fashion.

    Finally, to explain my cryptic remark on statistics, there is a preponderance of use of statistics that depend on Gaussian probability (models employing Gaussian processes) whereas the climate, and weather, and economy and interactions of all such are strictly non-Gaussian, non-stationary. Treating climate uncertainty in this manner will lead to exactly the result of Long Term Capital Management treating risk calculations in the derivatives markets as Gaussian processes.

  47. 47

    The line that needs to be drawn between scientific neutrality and social responsibility per the discussion between Dave and TM Lutas is an important and non-trivial question.

    I don’t think that scientists ought to be policy advocates in general, but when the public and political perception of the state of knowledge is willfully and consistently misrepresented by paid propagandists, the usual scientific style of expression gets lost in the shuffle. What’s intended as an error bar gets passed through “uncertainty” and “imperfect knowledge” to alleged “ignorance”. At some point, we need to stand up for our work and say, “no, we really do know what we are talking about, and here is what we know.”

    I suggest that the scientific community has a moral responsibility to make sure that the public and the policy sector understands the state of knowledge in a situation of such importance well enough to take appropriate action. Such understanding doesn’t exist at present, at least not everywhere.

    For us to say what we say in the expected formal, equivocal scientific way, is tempting but apparently inadequate. This is what we have been doing, and we see that the extent of public understanding of the science is, if anything, in retreat (especially in the English-speaking countries, for some reason). While we qualify and equivocate in the formally correct manner, those with narrowly affected economic interests who seek to undermine public understanding are in no way constrained to argue fairly.

    Staying cool and neutral and above the fray is the natural tendency of most scientists, and as Lutas points out, is not just culturally expected but demanded. I disagree with Lutas in his suggestion that we be extremely rigorous in this regard, as long as so much confusion is arrayed around us.

    We shouldn’t say things that are wrong, and as much as is reasonable we should stay out of policy debates in our professional capacity. That said, it is not in the interests of the field or the public that we be underestimated or misunderstood. In the present circumstances, we need to advocate for our results, not just state them. The line between advocating for the science and advocating against policies that seem thoroughly out of touch with the science is not always clear, and that’s where the difficulty arises. Erring on the side of neutrality may be taken to excess, to the detriment of the field and the world alike.

  48. 48

    Mr. Kilty’s questions, far from being irritating, are in my opinion salient and well-posed. I haven’t the time to do them justice right now even within my own limited capacity. I’m also uncertain whether they are in scope for this site, which is intended to be primarily about physical climatology and not about policy.

    Mr. Kilty also alludes to the question of how we can stabilize CO2 concentrations. I think this particular point is an excellent topic for an essay on this site.

    I maintain that both the near-term and long-term picture are dominated by coal. The petroleum situation is likely to take care of itself soon enough. There really isn’t enough known or anticipated petroleum available to do the sorts of damage we are most worried about. The total fossil fuel reserves are dominated by coal (unless you count clathrates, which is another topic we ought to take up) and it is those reserves that can easily quintuple the carbon load of the climate system. I believe that the focus on vehicles and thence on petroleum is misplaced.

    see e.g.

    According to a report on David Appell’s blog last month, quoting the Christian Science Monitor, the US along with China and India are bringing up hundreds of new coal-fired power plants. This is infrastructure that will be with us for far longer than our vehicle stock. Let me abandon scientific neutrality long enough to say that this is a very very very bad idea, much worse than big cars and bad train service.

    see (cached) under the heading “Future GHG emissions”.

    Also, I don’t think Kilty has told us enough about who has misused a Gaussian approximation and where to motivate a discussion. Perhaps he’ll try harder.

  49. 49
    Dano says:

    That’s an excellent post (47), Michael, and close to how I feel.

    Keep up the good work, sir.


  50. 50
    Ned Ford says:

    So many directions, so few of me to follow them. The original topic, the “precision” of the term “Global Warming” probably deserves discussion in light of the fact that the entire scientific topic defies precision in so many ways it is hard for even like-minded people to agree substantially. I’ll pick on an aspect of this that is previously undiscussed here: ocean chemistry. The problem we are concerned with is the result of certain human activities which involve many pollutants, but primarily fossil fuels. NOx and SO2 affect climate certainly, both through their positive and negative forcing roles, and through the changes in precipitation that were identified in the last two years. So the Greenhouse Effect is one part of this.

    But major impacts from this group of pollutants are not limited to warming. SO2 and NOx are generally regarded as respiratory health threats and their climate role is considered secondary, but most of the other greenhouse gasses cause other impacts as well (the ozone hole). The one I am most concerned about is ocean chemistry. If you go to and download the Abstract Book (look on the left panel) you will find enough background to confirm that this is a matter of serious concern, perhaps as much so as the high end of the warming estimates currently being taken seriously. To sum it up to a group of people who haven’t previously mentioned it, rising C in the ocean acidifies the water, and over the next century may change the pH of the ocean sufficiently to drastically change survival rates for the most common plankton and corals. Which in turn raises questions about the viabilities of the fisheries and even the ocean’s role in refreshing oxygen. Not permanently, but perhaps strongly during the millenium of carbon emissions.

    Thus the problem caused by emissions of fossil fuels is not accurately considered by the term “Global Warming”. It is adequately reflected in “Climate Change”, and I’m warming to “Climate Disruption”. Because I make some effort to accomodate imprecision, I’m quite happy to see a variety of terms tossed into the ring, so we can see which one is left standing.

    I’m reminded that linguists feel that a complete conversation consists of four statements, the initial comment, an acknowledgement that reflects the comment from the listener, an affirmation (or correction) by the original speaker, and an acknowledgement of the third statement by the listener. This is reflected in debate format, and our legal system, but not in blogging. I’m not sure how it could be, given so many speakers and listeners, but I’m thinking about it. Do societies conform to the same rules of communication that individuals do?

    Comments on other threads embodied in this one:

    I want to note that people who make assumptions about the impossibility of controlling CO2 emissions without economic harm are ignoring the fact that there is a massive untapped potential for efficiency improvements. The world has decreased per capita emissions since some time around 1980, and this is largely due to the ongoing application of these efficient technologies. Yet the technologies continue to improve faster than we are implementing or adopting them. This site would do well to have a detailed discussion of the economics of CO2 reduction. There is plenty of evidence that the no-losers’ strategy to controlling CO2 is of primary importance in preserving and improving economic growth in the near future in the absence of any concern about climate. Many many many examples, but DOE’s Clean Energy Future report (on google) for example finds that an aggressive CO2 control strategy (not very aggressive by my standards) costs 18% less than doing nothing, over 20 years. California saves about $14 billion per year (50% of total electric spending) as a result of almost 25 years of spending about 1% ($200 – $300 million) per year on efficiency.

    Gilbert Plass demonstrated in the 1950’s that the saturation of CO2 in the lower troposphere did not preclude a warming impact from increasing CO2. I’m still looking for the actual study in which he describes this demonstrtion, but Spencer Weart’s book “The Discovery of Global Warming” and his website make it clear that this was a critical event in the evolution of current science. (Weart is a historian for the American Institute of Physics).

    I would like to agree that petroleum is limited, and by the same token, natural gas is too, but the economics of oil shale and other synfuels is such that it is entirely feasible to release an enormous fossil reservoir of these substances as vehicle fuels if we are not lucky enough or deliberate enough to move toward efficiency and renewable resources. Synfuels were already on the market at oil prices of $20/barrel, and today’s prices make it a sure thing that more will be coming, if all that is relied on is market prices.

    Australians are rude, which is why Continental Shift placed Australia so far away from the rest of us. But in light of the imprecision of this subject, Australians have a purpose. I’m also still not sure what it is, but I remain open to their contributions.