RSS feed for comments on this post.

  1. You say that the scientists did not deliberately mislead the journalists. Well, they did. Out of a couple of thousand runs, the average was 3degC with only one or two results at 11degC. To only mention ‘up to 11 degC rise’ is deliberately misleading. Any true sicentist knows that the 11 degC does not represent anything meaningful. This was deliberate headline grabbing. Now, if it is acknowledged that dramatic statments are required to get your science into the news, this may well be valid. But at the same time, the scientists must be honest about what this is, and not, as Myles Allen does, is to come up with some pitiful ‘politician-style’ defence of the indefensible.

    [Response: No. The whole point of the study was to examine the range of sensitivities you would get. The mean was set in the initial set up and could not be described as a result – the result was the range and since the range ended up being skewed to the high end it made sense to describe that. However, the context in the release was not sufficient to make that clear. -gavin]

    Comment by PHEaston — 21 Apr 2006 @ 4:57 PM

  2. National Geographic News reports that this week’s issue of Nature will publish a study from a team led by Gabriele Hegerl of Duke University which finds climate sensitivity of 1.5º to 6.2ºC, with a higher end somewhat higher than the standard range of 1.5 – 4.5ºC.

    The title of the National Geographic News article is “Climate Less Sensitive to Greenhouse Gases Than Predicted, Study Says” (emphasis added).

    Since the study apparently found a high end of sensitivity which is greater than the standard high end (6.2ºC vs. 4.5ºC), how come the title tells us that it shows the climate is “less sensitive than predicted”?

    Because the title is comparing Hegerl’s results not with the standard range, but with the subject of your post, namely “recent research suggesting that the climate may be susceptible to extreme increases in temperature”, noting that “Several studies have found that the temperature change may be higher than 16.2ºF (9ºC). One estimate put it at 19.8ºF (11ºC).”

    The NGN article itself gives a good explanation of climate sensitivity and the various studies and estimates of it, and does quote Michael Schlesinger of the University of Illinois saying that Hegerl’s result “means climate sensitivity is larger than we thought for 30 years, so the problem is worse than we thought. This doesn’t give us any solace.”

    But the title certainly seems to misleadingly suggest that Hegerl’s result indicates the problem is not as bad as we thought.

    [Response: This only makes sense in the context of the Stainforth et al results (and a few others). The ‘we’ in the last sentence is a bit ambiguous because nobody actually thinks 11 C is likely (or even plausible). What the ‘in context’ translation would be is that ‘the results rule out some of the high end stuff previously reported in the media‘. Schlesinger’s response in the article is not quite valid either – there are other constraints that mean even Hegerl’s top limit is too high (as linked to above). – gavin]

    Comment by Doug Percival — 21 Apr 2006 @ 5:01 PM

  3. OK, I’m admittedly totally biased, but with all the misinformation out there from so-called “climate scientists” (i.e. anyone with an opinion on global warming, plus their grandmother), carping on the +11C sensitivity on the CPDN press release is a bit much.

    The proof is in the pudding — and for the few examples on the show that can be scientifically disproven (whether in the peer-review stage or later publications), then it seems that science is doing its’ thing. There are far worse things being done by “scientists” with an agenda, already biased opinions that leapfrog onto anything they see as backing up their psychoses or appeasing their right-wing think-tank supporters. Not to mention just plain old schadenfreude & jealousy & ambition. Please refer to “beams & motes in eyes” etc.

    (as a disclaimer, although I work on the project and am named on the Stainforth et al paper; I was not employed nor around at the time of the press release in question (not that they would have cared for my opinion anyway, as I’m a computer geek and not a climate scientist ;-)

    Comment by Carl Christensen — 21 Apr 2006 @ 5:16 PM

  4. PS — it was not “one or two results at 11degC” (it was a low probability, yes, but not “one or two results out of 2000 results). jeez everyone is just dying to chop our “fat tail” off by any means necessary! ;-)


    Comment by Carl Christensen — 21 Apr 2006 @ 5:19 PM

  5. As one that used to be a firm believer in Global Warming and Kytoto, I decided to nonetheless to do my own research in the matter.

    I read the contents of the IPCC report (not the conclusions) and I was impressed with all the actual information that is in there. Everyone for or against the theory of GW should read it. It is imformative. I have also lurked around the usual GW discussion web sites that either favour or oppose the theory. I have stayed away from NGO and oil companies web sites.

    However, I must say that I have a lot more doubts about Global Warming that I used to. I, too, was under the impression that there was proof that 1) Global Warming was a fact and 2) It was induced by human behaviour. My information in the matter had been provided by general TV and newspaper articles.

    For me, what I don’t like to hear in the media are the following:

    1) CO2 is a “pollutant”.

    [Response: Many other pollutants are also present naturally in the atmosphere, at low concentrations. A pollutant is any constituent whose concentration we increase to the point where it can cause harm. In this regard, anthropogenic CO2 is clearly a pollutant. –raypierre]

    2) Greenhouse effect is a “bad thing”.

    [Response: The natural greenhouse effect is a good thing, since the Earth would be frozen over without it. The anthropogenic increase of the greenhouse effect has many demonstrated adverse consequences, but the main reason for not blithely assuming it will be benign is that the human species has done pretty well in the climate we’ve evolved in over the past two million years, and the amplified greenhouse effect really takes us into unknown territory so far as impacts go. –raypierre]

    I think that the debate about it being an unproven theory is quite justified and needed.

    My doubts are the following:

    1) Even though CO2 concentrations in the atmosphere has gone up by 30% over the last 200 years or so (compared to being stable for 400 000), I have a hard time to comprehend how an increase from 0.028% to 0.038% of CO2 by volume can have any effect on the thermal mass of the atmosphere considering that water vapor by volume is 50x greater and has higher thermal coefficients. Is this physically possible? Why aren’t we seing atmospheric H2O time plots as well?

    [Response: See the various posts on RealClimate regarding water vapor,particularly Gavin’s post on water vapor feedback and my post on “A Busy Week for Water Vapor.” Water vapor amplifies the effect of CO2. It is difficult to monitor, but there is now satellite evidence that water vapor in the atmosphere really is increasing with temperature, in a way that yields positive feedback. The CO2 doesn’t alter climate by affecting thermal mass; it affects climate by retarding the efficiency of infrared radiation, and it has important IR absorption bands in places where water is ineffective. –raypierre]

    2) There seems to be some valid correlations between the Sun’s activity and temperature variations over the last few hundred years.

    [Response: Most of the more spectacular looking correlations are bogus, a result of manipulating data, as has been reported in EOS, and various places on RealClimate. IPCC does take into account solar variations in a physically-based way, and they don’t account for the 20th century temperature rise. –raypierre]

    3) The temperature variation of the 20th century is non-linear while CO2 increase seems to be.

    [Response: You really need to read the IPCC report more carefully. There are other climate influences beside CO2, notably anthropogenic and volcanic aerosols, as well as some solar fluctuation. It’s these that account for the irreguarities in the temperature increase. –raypierre]

    4) The evidence about the medieval warming period and little ice age are convincing and supported by different methods.

    [Response: How is the little ice age an argument against CO2 sensitivity? The medieval warm was not a global event, was probably not synchronous even in the Northern Hemisphere, and was probably not as warm as we are now — and certainly was not as warm as we’ll be in 2100 if CO2 continues to increase. You’ll have to make it more clear just what you mean by this objection. –raypierre]

    5) There is a possibility that higher CO2 concentrations is a result of warming rather than the cause.

    [Response:No, there is no possibility of this. There are a vast number of lines of evidence that the industrial age CO2 increase is a result of human-caused emissions. There is absolutely no doubt of this. It is a point that is so certain that even most of the skeptics agree that the rise in CO2 is caused by humans. –raypierre]

    My conclusion: Man made GW is an unproven theory. It hasn’t been proven or disproven either.

    [Response: See my post “Happy Birthday Charles Darwin” In science no theory is ever definitively proven, but GW is proven to a far higher degree than most other theories on which governments routinely make very consequential decisions. –raypierre]

    We should continue to reduce Fossil Fuel emissions for other reasons than GW.

    [Response: Yes, there are multiple reasons for reducing emissions. However, nobody would go to the bother of sequestering Co2 from coal fired power plants if it weren’t for concern about GW. Things like building energy efficiency and better fuel economy are another story, and can be justified with or without concern about GW. –raypierre]

    1) Reduce the other really nasty air pollutants.

    2) Preserve the energy resources for future generations

    Not that it really matters but I graduated in Electrical Engineering at Queen’s University in Canada.

    Comment by SC — 21 Apr 2006 @ 5:27 PM

  6. Amen, Gavin. Scientists whose work reaches the public need to think hard about that dynamics of that transaction, as you obviously have. It’s great when they combine their natural deep awareness of the actual implications of their work with an acquired deep awareness of the ways in which those implications could be misunderstood, misreported, or distorted.

    It is not at all to disagree with you, then, that I’d add something: no solution is perfect, and if certain scientists get too much of a veto over wordsmiths, there can be costs to the quality and value of communications. I’m thinking, just for one example, of a time when some of us were asked to craft one single sentence for use by the governor at the state capital in a public ceremony, and the principal scientist involved insisted that the sentence needed to include the word _stochastic_. Sheesh. Another problem can be certain scientists’ unwillngness — or maybe it’s just inability — to recognize that an ounce of benign semi-inaccuracy can sometimes save a pound of droning, confusing, communication-quality-undermining, though precisely accurate, irrelevancy. But those kinds of risks are better to take than the kind you’ve focused on, because (in my view, anyway) you’re right: not all publicity is good.

    Comment by Steven T. Corneliussen — 21 Apr 2006 @ 5:27 PM

  7. Gavin, some points. As far as what journalists read, it depends on the journalist and the audience. I think it’s fair to say that most journalists get their news from the press release. But a surprising number ask to see the study. For instance, I’ve gotten a number of requests for copies of a study for which I wrote the news story.

    See here:

    Here’s the typical pattern which I can tell you is replicated by most people I know who work at ES&T, Science, Nature, Reuter’s Health, JAMA, and other organizations.

    1. Get paper. Read two sections–the introduction and the conclusion.
    2. Send out paper and explain to researcher that it’s embargoed, not to be passed around.
    3. Interview primary author, and a couple others for comments.

    This is for a quick and easy “new research finds” type of story. Others can be more complicated.

    [Response: Paul, I didn’t mean to imply that conscientious science journalists didn’t exist, they certainly do. But unfortunately they’re not the only people covering this beat. – gavin]

    Comment by Paul — 21 Apr 2006 @ 5:41 PM

  8. Since you bring it up, I agree that the “Annan and Hargreaves ignored” point was probably a little stretched – but note that they only said “ignored”, not “deliberately ignored”, and the original rejection was indeed on the grounds that an editor (explicitly on consideration of it’s media-friendliness, not the scientific content) judged that it was not sufficiently interesting to merit coverage. Of course, the program also cut its timing fine cos the paper rates an oblique mention in Science this week alongside Hegerl et al :-)

    I think we all agree it’s a fine line to tread between presenting the research in an engaging and interesting manner, and being tempted into exaggeration. I thought the programme addressed this issue in a pretty reasonable manner.

    [Response: In doing interviews on the Hegerl paper, I also suggested that the journalists contact you and refer to the A+H paper. That’s another way that journalists can find context. PS. I made an error in suggesting there wasn’t a press release on your paper – sorry about that! – gavin]

    Comment by James Annan — 21 Apr 2006 @ 5:43 PM

  9. Thanks for these great words of caution. A press release I was involved with last year is at least one other example confirming some of what you say. I had led a GRL paper showing unprecedented NOx enhancements and O3 reductions in the upper stratosphere during the Arctic late winter/spring of 2004, an indirect result of energetic particles [Randall et al., Stratospheric effects of energetic particle precipitation in 2003-2004, GRL 32, L05802, doi:10.1029/2004GL022003]. In another post on this site, Markus Rex referred to this paper, noting that the press it received had the unfortunate effect of causing confusion (comment by Markus Rex on 24 March 2005, in response to a post on 10 March 2005 “Will spring 2005 be a bad one for Arctic ozone?”). I agree that it did.

    The results presented in the GRL paper are a remarkable example of how our atmosphere responds to a unique set of natural events, so they are certainly of general scientific interest. I wrote the first version of the press release, and at least was savvy enough to add a paragraph (that was intended for the press officer, not for release) that this had the potential to be confused with the ozone “hole”, so we needed to make sure that the final version was entirely clear on this matter. We went to great lengths to include all the necessary qualifiers (e.g., this was in the upper, not lower, stratosphere) within the space limitations.

    Yet some of the media reports still ended up implying that solar effects might be responsible for an Arctic ozone hole, and that therefore anthropogenic effects might not have caused the Antarctic ozone hole. I discussed this problem in a university critical thinking class that I taught this semester, and one of my students made a very good observation: The title, although accurate in one sense, was misleading.

    The press release was entitled, “Huge 2004 stratospheric ozone loss tied to solar storms, Arctic winds”. To my narrow way of thinking, this of course *was* a huge (as poorly quantified as that is) stratospheric ozone loss â?? because I was focused on 40 km. But in terms of the column it was only about 3 Dobson units, so looking back on it, it was understandable that the release led to some confusion. On the other hand, had we inserted â??upperâ?? before stratospheric, Iâ??m quite certain that some confusion would still have ensued. I should add here that the confusion was not universal, by the way, and some media reports with widespread audiences got it right. In any event, one lesson learned here was precisely as you stated; that the title of a press release sets the tone for what the reporters will infer from the text, with a fine line between being misleading and still capable of capturing attention.

    The latter brings up an interesting point, however. When should a journal article be publicized? Only if it appears in journals such as Science or Nature? What if it appears in less general but timely journals such as GRL? Or maybe only if it is obviously relevant to policy? In other words, to what extent is it the scientistâ??s responsibility, and to what extent is it the mediaâ??s responsibility, to try to educate the public on issues that are of general scientific interest? As you note, drama sells to the media. Few scientists I know do work that is dramatic, so somehow we need to understand how to most effectively capture the publicâ??s attention so that the wealth of information that scientists are producing is not buried in the scientific literature.

    Comment by Cora Randall — 21 Apr 2006 @ 5:59 PM

  10. Gavin, I’m frankly horrified at your comment that “most journalists will only read the press release, and possibly only the first couple of paragraphs of the press release. Very, very few will read the whole paper.” You and the other RC people deal with a lot of reporters. Is this really your experience – that they’re not reading the papers y’all write?

    [Response: John, Not at all. The journalists I deal with in general are extremely conscientious and really make an effort to understand what the papers are about and canvas a wide range of opinion before writing the story. However, not all journalists that cover science are actually science journalists, and for a big story it’s often the news desk that gets the job. I don’t think it’s their fault, but news journalists don’t have the background or contacts that you or Paul or Andy have. I apologise if it seemed that I was criticising good science reporting – that was not at all my intention. – gavin]

    Comment by John Fleck — 21 Apr 2006 @ 6:02 PM

  11. I too feel that the publicity given to the possibility of 11K sensitivity was unfortunate and that a more strenuous effort should have been made to avoid it. The possibility of there existing a plausible model with such a high sensitivity is of such overarching importance, I would have liked to have seen one such model chosen, and to have available all of the standard runs being provided for the IPCC Fourth Assessment by the major modeling centers, in the same format used by those models, so that the climate community could judge for itself the plausibility of this model’s climate simulation. Even without the ice age test, which ideally all models will eventually use, I find it hard to believe that one could not rule out such a high sensitivity model in a host of ways.

    An additional interesting question is whether the huge ensemble of models used in this study is actually more valuable than the 20 or so models generates by the best efforts of the world’s modeling centers for the IPCC. Arguably, the 20 “best shot” models could be providing a more meaningful selection of interesting points in the “space of all possible climate models” than those obtained by exploring so exhaustively the neighborhood of one particular model in this space. I think this is an open question.

    Comment by Isaac Held — 21 Apr 2006 @ 6:45 PM

  12. Re #6. John, I’m afraid if you were a sensitivity projection you’d be 11C. :) My suspicion is that most science reporters will vary considerably the amount of background work they do based on the importance of the story and their deadline situation. In the context of daily newspapers or broadcast media in particular, I would bet that not reading the paper itself is very common as long as the press release appears thorough and not sensationalist in tone and/or a credible science reporter (Andy Revkin e.g.) has already done a story.

    Comment by Steve Bloom — 21 Apr 2006 @ 6:56 PM

  13. Re #7 – If you go through the paper in the link above, you would find that the value (not “more valuable”) in the thousands of runs is in exploring the parameter space, and finding out that high-sensitivity models aren’t just a “one-off” that you can happily throw out when you do an ensemble of 5 to 50 or whatever. We are hoping to explore this more fully in our coupled model experiment. Although we had a recent snafu with our sulphate forcing file which you may have seen reported (now THAT is publicity which is not good ;-)

    I still think that the blogosphere is getting a bit alarmist about alarmism. Let’s face it, the worst thing from the CPDN press release was that the London Metro (the free paper on the Underground) made it seem like we said the earth would be 11C hotter by 2100. Anybody glancing at the paper could see that’s absurd.

    Yet while pointing out the motes in our eyes, the beams in the eyes of the Cato Institute, George Will, Ebell, Lindzen, and every other non-scientist posing as a “climate expert” often gets ignored. Not that we should stoop to their levels, but at least we have the science and terabytes of model data behind what is at worst a little hyperbole on a press release. So have another chablis after you’re done patting yourselves on the back that you have yet another 3K sensitivity model to report, and you chopped off all the outliers so as not to offend Fred Singer even more! ;-)

    Alarmism? In a world that has “Saddam can bomb us in 45 minutes” and “Saddam was behind 9/11” as typical fare from the media establishment? It is to laugh….

    Comment by Carl Christensen — 21 Apr 2006 @ 7:12 PM

  14. Am I missing something?I am a self taught individual regarding global warming. I’ve read most all the press releases in ENN and ENS and the regular newspapers regarding global warming. I also read about all the scientific studies that hit the news, and read Scientific American ,and some other publications. I am in no way a full expert, but I believe that by looking at sites like Real Climate and Pew Center for Climate Change that I’m well informed. Why should we shield the public from the bad news? I’ve read that temperature changes may be even much greater that those talked about above.Some environmental groups say we c’ant paint too bleak a picture becauses people and governmnents will just give up. I say that if they d’ont realize the full potential of the catastrophe they will never come close to the 80% reductions in co2 emmision we need now. Coddling the public is not the answer. They need to know the worst case scenarios, and that the worst case potential has gotten much worse over the past two years, given the magnitude of efects which we are seeing now, predicted for the year 2100.
    Mark J.Fiore

    [Response: This isn’t a matter of shileding the public from bad news, its a question of fairly presenting the results in an accurate way, and not over-emphasising extremes – William]

    Comment by Mark J. Fiore — 21 Apr 2006 @ 7:15 PM

  15. In my journalism training I was given a number of press releases from which I had to craft a story by contacting the people in the release. I had to read them by default just to be able to continue. However headline writers are likely to just trumpet some aspect that may not have been portrayed as the most significant thing in the study. Moreover, they will actually edit out context just to save space.

    I think this deliberate campaign by people like Milloy is very damaging since these are the readers that decided the last two elections. Anything that plays into those hands is not a good thing. Overblown claims of temperature rises are just what they wait for.

    Comment by Mark A. York — 21 Apr 2006 @ 7:42 PM

  16. I read the paper in Nature. One of the possible causes of the extreme results is clear: parameters were chosen to represent upper and lower limits of elements of the model, which the authors themselves describe as, “the perturbed values chosen, which were relatively arbitrary.” They go on to state, “In our case even the physical interpretation of many of these parameters in ambiguous.”

    That’s probably why, as the authors state, “Six of these model versions show a significant cooling tendency in the doubled-CO2 phase.” Those (admittedly very few) simulations were omitted from the analysis, but as far as I can see, no simulations were omitted because they seemed unrealistically high.

    In my opinion, the science is sound (given the limitations) and the paper is both frank and honest. I think it makes the point validly that climate sensitivity (response to doubling CO2) above 5 deg.C is at least possible, albeit quite unlikely; a conclusion borne out by many other arguments and simulations. My best guess is that the actual probability of extreme sensitivity is well below the result of their simulations (~ 10%), but above previous belief, which seems almost to rule it out completely.

    On the one hand, even if the probability of sensitivity > 5 deg.C is very low — say, < 0.001 -- the consequences of that much temperature change is high enough that probability x consequence can still be non-negligible. So, we as scientists should be very concerned. On the other hand, the probability is low enough that public statements based on this possibility will open us up to more ridicule than trust; we're giving ammunition to contrarians when we publicize extremely unlikely outcomes. Thanks for providing the link to the article from Nature. Any chance you can link to, or post, the press release?

    Comment by Grant — 21 Apr 2006 @ 8:11 PM

  17. re 9. … Am I missing something? …

    Are you?

    Those who just give up are missing something.

    Emitting fewer GHG emissions now will result in a volume of accumulated GHGs at a given point in the future that will be less than it would have been had we not emitted fewer GHG emissions. Thus, at that point in the future, a lessor volume of accumulated GHGs in the atmosphere would mean a global climate that is not as warm as the global climate would have been had we not emitted fewer GHG emissions now. Therefore, it’s best to emit fewer GHG emissions now, for the sake of those who are living at that point in the future … the young people now, their children and maybe us. What matters most to me is the climate which young people and their children will have to deal with as they grow older. It is our moral obligation to emit fewer GHG emissions. How much fewer? … as much as we can.

    Comment by pat neuman — 21 Apr 2006 @ 9:02 PM

  18. Anyone,

    Is the press release (link below) an example of how-not-to-write-a-press-release? What’s good or not so good about it?

    Senior Scientist: Rapid Global Warming is Happening Now
    10/30/2003 8:28:00 AM

    Comment by pat neuman — 21 Apr 2006 @ 9:38 PM

  19. I am sympathetic to Carl Christenson. We must keep a sense of proportion. The press release announcing the results was not an entirely admirable example of publicity, but it’s not a scandal either. We are holding our field to a very high standard, and that’s as it should be, but the transgression here pales to the point of disappearance compared to what has been routinely perpetrated by the likes of Milloy, Crichton, Lindzen, Bill Gray and the like. Any mistake has been amply rectified, it is possible for people to read the original paper for the full (and entirely defensible) story, and we won’t be going around crowing that models show there will definitely be an 11C warming in 2100 — a contrast with, say, Milloy, who is still saying that Jaworowski trumps 1000 peer reviewed papers on Pleistocene CO2. The most unfortunate thing is that the somewhat clumsy press-release obscured the true message, which is that physics alone does not rule out high sensitivities, even if you impose the requirement that the model match the present annual mean climate. One can temper that with studies of paleoclimate sensitivity, but the ensemble results still should be borne in mind, since doubling CO2 takes us into a climate that has no real precendent in the part of the climate record which has been used for exploring model sensitivity, and in many regards may not have any real precedent in the entire history of the planet (in terms of initial condition and rapidity of GHG increase). There’s no doubt that the result is an important contribution.

    Comment by raypierre — 21 Apr 2006 @ 10:26 PM

  20. Re: #18

    I’m interested in the opinions of others on this, and I’ll offer mine. I think it’s a good example of how NOT to write a press release. The press release has very little to do with the study to which it refers (which I also read). Instead, it seems to be a forum for the paper’s author to express his concern about global warming, and his certainty about its cause (anthropogenic). Although I share his opinions, his *paper* is only relevant to evidence of warming in one small geographic location and has nothing to do with the likely cause of warming.

    In fact, having read the paper, the “press release” doesn’t seem to be a press release at all. At least the press release about the Nature paper (Stainforth et al.) is about the results of that paper!

    Comment by Grant — 21 Apr 2006 @ 11:16 PM

  21. Regarding comment #5. I would like to see SC respond to raypierre’s comments. SC has fallen prey to misconceptions right out of the standard, knee-jerk skeptic playbook, either because he didn’t read the IPCC report carefully (or in an open-minded enough way) or because he hasn’t kept up with the literature (e.g., Damon and Laut, 2004). The ball’s in your court, SC. Are you convinced by RayPierre’s comments or not. If the latter, why not?

    [Response: Well, nobody should be convinced by my comments alone. They are only pointers to further reading (like Damon and Laut, or the various references in the RealClimate posts I mentioned). It’s only after reading the background material that they should be convinced. –raypierre]

    Comment by Rob Negrini — 22 Apr 2006 @ 12:22 AM

  22. A press release for the paper by Annan and Hargreaves WAS issued on 1 March, here:
    Yes, it is in Japanese. And its English version
    appeared online actually a week later. Perhaps the delay was not intended. The administrators of our institution usually try to make equivalent PR materials in two languages. But it seems that their primary preoccupation is that our institution must be visible to Japanese taxpayers.
    (Aside: I am not another K. Masuda whose name appears as the contact point of the press release.)

    [Response: My mistake. Apologies all round. – gavin]

    Comment by Kooiti Masuda — 22 Apr 2006 @ 4:00 AM

  23. Well I find it sort of amusing (and a little tragic) that climate scientists (at least the blogger ones) are patting themselves on the back over their high standards of a press release that will just focus on the mundane “we also show a 3K sensitivity as most likely.”

    And then act “ever so ‘umble” that they aren’t investigating the extremes, so as not to seem too “mad” or “liberal” or “wild.” So then they work on constraining things to chop off the extremes, as if the skeptics will even allow them a 3K increase.

    So what we have in the climate change area (and what I find fascinating for cynical reasons) is that everyone and their grandmother, whether they be lawyers, anthropologists, economists, semi-retired mineral engineers, poets, old academic codgers, weigh in on this scientific issue often with more aplomb and fanfare than the actual scientists (earth obs through modellers) themselves. So the great mass of scientists is far behind in the battle for minds even before they get started. But they’ll send out a conservatively-stated press release, by god!

    Let’s get a grip — a little hyperbole in a press release is to be expected — the critical moment is whether the science is backed up. I’m starting to whiff a bit of jealousy behind the sanctimony over “alarmism in the media.”

    [Response: Indeed, let’s get a grip. None of the scientists here or who have commented on the matter are short of media exposure, so I don’t think there are any ‘whiffs’. Scientists are indeed conservative (small c), and they need to be – but that doesn’t mean that they systematically underestimate effects – it means they try and assess the most likely outcome plus how unlikely it is – on both ends. No-one is expecting perfection here, just a wider appreciation of what ‘best practice’ could be. As I’ve said before, I’ve been very supportive of the project and I think some great science is being done. This ‘issue’ is indeed a bit of a distraction, but there are lessons that are worth learning. -gavin]

    Comment by Carl Christensen — 22 Apr 2006 @ 5:20 AM

  24. #23: Re to Carl Christensen: Well said Gavin. But I would like to say scientists are being “responsible” when trying to assess the most likely outcome and by quantifying the uncertainty involved in that, not “conservative.”

    Comment by ocean — 22 Apr 2006 @ 8:16 AM

  25. Re #5 I would like to take up one point where I felt Ray had not given the full story, perhaps because it is political. SC writes:

    — For me, what I don’t like to hear in the media are the following:
    — 1) CO2 is a “pollutant”.

    and he writes:

    — We should …
    — 1) Reduce the other really nasty air pollutants.

    Scientists are well aware that CO2 is not a pollutant. The OED definition of pollutant is something that is foul and filthy. In fact, carbon dioxide is natural and neccessary for life. Without CO2 there would be no vegetation. Without vegetation there would be no food for animals or mankind. Without CO2 we would starve to death. OTOH, with too much CO2 the global temeprature would rise to such an extent that all plants would die, much as happened at the PT mass extinction, and we would be exterminated too. With just a little less CO2 we might enter a new ice age, or with just a little more CO2 we might enter a greenhosue world, similar to that at the time of the dinosaurs.

    But I am sure Ray is very familar with all of that. What he might not be aware of is that it was GWB who introduced the idea of greenhouse gases being a pollutant. GWB was interviewed by Science prior to the 2000 election [Science 13 October 2000 Vol. 290. no. 5490, pp. 262 – 269], and when asked about greenhouse gases claimed that he had a good record of dealing with pollutants!

    Science: What is your view of the scientific evidence that attributes global warming to human activity? Should the United States take steps in this decade to reduce its emission of greenhouse gases? If so, do you favor annual targets or another mechanism?

    GORE: There can no longer be serious doubts that human economic activity is affecting the global environment. While uncertainties remain, …

    BUSH: As governor, I’ve taken steps to reduce harmful, ozone-forming pollution. In 1999, I signed two landmark clean air bills that will reduce industrial air emissions an estimated 250,000 tons annually–the equivalent of removing 5.5 million cars from Texas roads and highways. One of those new laws mandates that by 2003 older power plants must reduce their emissions of nitrogen oxide (by 50%) and sulfur dioxide (by 25%). This law …

    In other words, what Bush has done is try to minimise the dangers from CO2 by lumping them in with the air pollutants SO2 and NO2. If, as a result, it means that educated people like yourself think that scientists do not know the difference between a pollutant and a greenhouse gas, then so much the better for his oil industry :-(

    [Response: There’s a lot of truth in what you say, and certainly even if I want to call CO2 a pollutant, I will freely acknowledge that the way it does harm is very different from the way NOx or tropospheric ozone or mercury do harm. I would argue, though, that the OED notion of pollutant is behind the times. The question of “what’s a pollutant” is a little like the question of “what’s a weed.” –raypierre]

    Comment by Alastair McDonald — 22 Apr 2006 @ 8:47 AM

  26. This comment is closely related to, but is not directly on, the present thread’s topic. That is, it’s off-topic in that no amount of fair-minded, journalism-aware wisdom by press-release-writing scientists can change what the Wall Street Journal is doing — and is doing again this morning. But I hope RC will let this comment fly anyway. Today’s WSJ editorial “Breathe Easier: The world is getting cleaner, Al Gore notwithstanding” is available freely on the open part of the WSJ’s site, In my view the editorial illustrates yet again why this overall discussion about climate scientists’ communication with the rest of society is important. Some highlights:

    * The editorial repeats an old charge by asserting that “the global-cooling crisis has become the global-warming crisis without missing a beat.” It shows no sign of awareness that that charge has been rebutted, or of any response to the rebuttal.

    * The editorial continues the WSJ’s disregard of the difference in significance between odd weather events and climate change overall, which is the basis for a running gag that the WSJ’s James Taranto uses in his Best of the Web e-mail column — usually, but not always, by targeting an instance when Al Gore gave a global warming speech on a really, really cold day. Taranto plays that juxtaposition as a funny irony, which in turn fits with his unserious sarcasm about the whole topic. But this time the WSJ adds a twist: it specifically cites the climate-weather difference, but then broad-brush-accuses all opponents of having used the weather event Katrina to generalize about climate — which is a true charge, but not about RC and other serious climate scientists.

    * The editorial also charges that “full-scale demonization of anyone who questions the global warming orthodoxy is now under way. MIT’s Richard Lindzen recently described in these pages how this intimidation is stifling scientific debate.” But the editorial shows no sign of response to the belief of many that the WSJ owes it to the world to give some responsible climate scientist a chance to rebut not just Lindzen, but the WSJ’s overall editorial stance on climate change.

    * Near the end, the editorial expresses contempt about the climate consensus, in part by putting the word consensus into what James Taranto himself calls “scare quotes.” Then it ends by quoting Winston Churchill in a way that’s meant to group the furthest-out global-warming alarmist with the likes of RC and other responsible scientists: “A fanatic is one who can’t change his mind and won’t change the subject.”

    Comment by Steven T. Corneliussen — 22 Apr 2006 @ 9:16 AM

  27. re 20. I’m interested in the opinions of others on this, and I’ll offer mine. …


    I’m interested to learn what you think the purpose (or purposes) of my 30 Oct 2003 press release were at that time. The press release was to represent my views only … not the views of NOAA NWS. I used my own money ($500.) to have it issued. The person who helped me issue it inserted a couple statements on his own.

    Comment by pat neuman — 22 Apr 2006 @ 9:22 AM

  28. Dear Gavin,

    We were naturally concerned when David Frame and I were interviewed for this programme at any suggestion we were “sexing up” the results of Stainforth et al (2005), so we asked Fiona Fox of the Royal Institution Science Media Centre, who convened the January 2005 press conference announcing those results, to follow up. None of those involved in the Battle for Influence programme were present at the press conference or covered the story at the time. Fiona kindly wrote to a number of journalists who were at the press conference asking them for their reaction to the “sexing up” accusation, stating:


    My own clear memory of this briefing is that the scientists were very clear that the results showed a range of warming between 2 degrees and 11 degrees and that each time they were asked about the impact of 11 degrees they reminded journalists that this was the worst case scenario and it could just as easily be at the lower end. Obviously we all knew (the press officers that is) that you would report 11 degrees and the fact that this was twice the level suggested by previous studies was clearly a significant news story. However I believe that the scientists themselves were very measured and did not emphasise the 11 degrees.

    Fiona Fox , Director
    Science Media Centre
    The Royal Institution

    The responses Fiona received were as follows:
    Hi Fiona,

    My memory tallies with yours. They presented the range, they described the concept of the ensemble, they emphasised (in response to a very perceptive question from some star BBC journalist) the role of clouds in the uncertainty, they mentioned 6 main reasons for uncertainty.

    If anyone went for the exaggeration it was the journalists – we all mentioned 11 degrees I’m sure but as far as I recall, PA and Metro presented it virtually as a fait accompli.

    Richard Black, BBC
    Thanks Fiona, my memory is as yours. Let me know what feedback you get and I’ll write you something properly tomorrow.

    Ruth Francis, Nature
    Hi Fiona,

    As I recall, the researchers, and Myles Allen in particular, emphasised the fact that the bottom end of the range (ie the 2 in 2-11 degrees C) corresponded to previous predictions of 2-5 degrees C. I seem to remember that they said this gave strength to the prediction that there would be a warming of *at least* 2 degrees C, but that there was a greater degree of uncertainty at the top-end. This last point was definitely underlined. To back that up, refer to Myles’ quote in my article:
    Hope this helps.
    Catherine Brahic
    Senior correspondent
    Science and Development Network (SciDev.Net)
    I’d agree with Catherine’s interpretation – as far as I recall, they were all quite careful to stress the greater temperature change the greater the degree of uncertainty. I’ll try and dig up the bulletins report.

    Sarah Mukherjee, BBC
    Hi Fiona – my memory is that the scientists took pains to point out that it was a range and quite a broad range at that. I also remember Myles in a rather vivid phrase saying that we had to remember that we could still take actions to avert the worst warming and that we shouldn’t assume “that our children will stand by and watch as the seas boil around them”, showing that the worst case wasn’t necessarily the most likely outcome.

    Fiona Harvey
    Environment Correspondent
    Financial Times

    As far as the press release, drafted and issued by the Natural Environment Research Council, was concerned, NERC assured us that recipients (including all those quoted above) would have received it attached to the paper and would have known that it was intended simply to draw attention to some interesting results in the paper, not to provide a comprehensive summary. We understand this point was not made clear to the scientists who were asked to comment on the press release, who naturally commented on the fact that it left a great deal unsaid.

    We told the Battle for Influence team about all this, but they refused to discuss revising their programme. Given that they refused to “spoil the story with facts” by interviewing any of their own journalists who reported on the original story, and went to some lengths to conceal what their programme was actually about when they first approached us for an interview, it seems they had already made up their minds at the outset and there was very little we could do about it.

    We think these responses speak for themselves, and that their allegation that we sexed up the results of Stainforth et al for the benefit of the media is simply false.


    Myles Allen

    [Response: Myles, thanks a lot for forwarding the comments – that’s very interesting. I might need to provide a context for the ‘sexing up’ comment for those of our readers who aren’t big BBC radio listeners though… – gavin]

    [Response:My personal reflection is that one big problem is that there is a culture difference between the science community and the media community (or perhaps the rest of Earth’s population?). A scientist may explain the problem in a very precise and dilligent way (which it sounds like what happened in this case at the press conference from the accounts above…), yet still the media cover may sometimes be framed in an incorrect way, for the various reasons provided above in this thread. I therefore think that this dicussion is very useful, and one important aspect of this is what Gavin calls for: how should we best solve this problem? How to bridge the two communities? Could we improve the situation by better press releases or having science-media conferences (e.g. Should scientists get more media training? The American Geophysical Union ought to be commended for its efforts to liase between media and scientists, and provide media training/experience for younger scolars. Or is the best answer to provide the community with a better background knowledge of natural sciences (thus making it easier to put things in context), and focus on improving science teaching in schools? One problem may be that some journalists do not have sufficient scientific knowledge, so should one reward journalists who go to the trouble of learning more about sciences (get some kind of credits, salary increases)? The Royal Meteorological Society (Am. Met. Soc. too, I believe) has a chartered status for meteorologists, perhaps journalists who report on science should have a kind of charter too, and that some journalists/editors should be more specialists? Then, there are the cases where text has deliberately been twisted to give a different meaning (to inflate the story, in debates, or in WSJ), and I think in those cases, blogs like RC come in really handy. Climate scientists who see their work being misreported could perhaps respond, by contacting the editor of the paper, issuing a second release, contact a widely read blog, etc. Perhaps there should also be some new routines recommended for journalists – like a check list (such as checking the publication history of the scientists, checking with other scientists, reading the whole paper, etc) for ensuring good reporting. Too many exaggerated/false claims will erode the credibility of science (just like for the WMD-reports). -rasmus]

    Comment by myles allen — 22 Apr 2006 @ 9:23 AM

  29. Re #2: Although the headline might have been poor, I didn’t think the National Geographic story on the Hegerl paper was too bad. Contrast it with this story in the Washington Times if you want an example of really bad reporting: [Although you got to love a line like “The Duke estimates show the chances that the planet’s temperature will rise even by 11 degrees is only 5 percent…” for the humor value. As if a rise of 11 F (which, as I understand it from Hansen is likely at least as much as occurred between the last ice age and now) is something to be considered rather trivial!]

    I do agree that an important reason why one has to be careful about writing a press release (besides the general principle of trying to insure the most accurate story gets told) is this way in which it comes back to bite you. I.e., we are now reaping the effect of several stories (and there are more than 6 now) on the Hegerl study that are emphasizing how the warming won’t be as bad as thought. If the possibility of an 11C sensitivity hadn’t ended up being oversold in the media in the first place, this would probably not have happened. [Some headlines are better though…for example the Washington Post headline is “Climate Change Will Be Significant but Not Extreme, Study Predicts”.]

    Comment by Joel Shore — 22 Apr 2006 @ 9:23 AM

  30. Re: #27

    I gave an opinion of the press release, considering it to be a report about the research to which it refers. Reading the press release, it seems that the purpose is to emphasize the seriousness of the AGW problem, and the need for the public and policymakers to treat the issue with more importance.

    As a summary of the research, I’ll stand by my earlier opinion (in #20). As a statement of the seriousness of the problem, I’d say it’s pretty good.

    BTW, I found your research fascinating. So, I tracked down your email address and sent you an email this morning.

    Comment by Grant — 22 Apr 2006 @ 9:38 AM

  31. Just a thought …

    As scientists, we constantly emphasize that we know the *science* behind AGW better than journalists. That’s OUR field! Maybe we should recognize that journalists know how to write a press release better than we do. That’s THEIR field!

    So, maybe the best way to write a press release is to collaborate with a journalist. They’ll know right away which claims are vulnerable to accusations of “alarmism,” they’ll understand which bits journalists are likely to latch on to, and they’ll certainly know when a PR needs a little more “sex appeal.” By collaborating, we can avoid both bad science and bad journalism getting into the public record.

    Comment by Grant — 22 Apr 2006 @ 9:52 AM

  32. SC said,

    Not that it really matters but I graduated in Electrical Engineering at Queen’s University in Canada.

    Not that it really matters, but I received a Master’s degree in Electrical Engineering from the University of California, San Diego. The degree requirements at my alma mater, curiously enough, did not include any climatology coursework.

    So color me unimpressed with your climatology credentials (which are certainly no better than mine).

    (So what is it about my fellow engineers, anyway? So many of my colleagues seem to think that an engineering degree endows them with special expertise in unrelated subjects like climatology or evolutionary biology?)

    [Response: For the record, I think any reasonably educated person, whether with a technical degree or not, should be able to understand and critically evaluate the basic arguments involved in predictions of global warming. We routinely have English majors and poets in our introductory global warming class that do very well. Some people say that because Crichton is only a medical doctor,he has no credentials to criticize the experts, for example. I’ve never bought that. I’d say instead that because Crichton has some scientific training, he really has no excuse for passing off bogus arguments as science. We are in a democracy, and for that reason I wouldn’t want people to just “trust the experts.” There are some things that non-experts will probably never understand, but the basic contours of the argument should be readily accessible to just about everybody –raypierre]

    Comment by caerbannog — 22 Apr 2006 @ 10:03 AM

  33. Re. #21

    “SC has fallen prey to misconceptions right out of the standard, knee-jerk skeptic playbook, either because he didn’t read the IPCC report carefully”

    First I would like to thank raypierre for taking a considerable amount of time in answering my post.

    You mention that I have fallen prey – that is you opinion. I did not “study” the IPCC report nor do I spend time to carefully study and verify scientific papers. What I have seen from the IPCC report is that the conclusion doesn’t really match the contents. It says that climate is impossible to predict , but it offers climate projections in the conclusion! It doesn’t even take into consideration that the temperature may actually decrease! Everything is on the positive side.

    Personally, I think that you can predict as the climate as much as you can predict the stock market. Taking 100 years of data of the earth is like taking 10 minutes of the stock market data and making predictions on where it’s going in the next week.

    I have noticed that the “misconceptions” you refer to are either re-inforced by those who oppose and are completely dismissed by those who favor the theory. You should consider myself as someone who is tyring to educate himself – not necessarily understand everything. A devil’s advocate I suppose.

    Living in Canada (Quebec – Excuse my french) I have to deal with the misconceptions that Americans are the worse polluters on the planet even though that Canada has increased their CO2 (and therefore all other pollutants) at twice the rate of the US. We are one of the worst energy consumers in the world by capita. People talk about the bad Americans without really looking at their own actions. Environmental laws in the US ae lot more severe and punishable than in Canada.

    BUT, if we are to implement an expensive binding agreement (Kyoto), it has to be based on strong facts. I don’t buy the argument that we should err on the safe side if we are wrong. It’s the same argument for going to War with Iraq based on WMDs. The argument now is that getting rid of Sadamm was not a bad thing – of course not but it was not worth the monetary cost but most of all the human cost. Back to GW, of course if we reduce pollution it won’t be a bad thing anyways – but the cost of being wrong will be quite high. Kyoto will probably stall the conversion of Coal firing plants to to Natural Gas since it doesn’t reduce CO2 production much anyways. But it does reduce all the other crap. In Quebec , we favour Hydro Electric. It is sold to the population as the cleanest energy on earth. But it’s not when you consider the ecological dammage it does. Kyoto will favor Hydro Electricity which is much more expensive and permanently dammages the environment (water and land). Of course no one sees the dammages in the far north.

    The bottom line to all this:

    There seems to be very little unbiased scientific eveidence available. The papers themselves are probably unbiased.

    Raypierre (he probably knows 1000 times about the subject than most) pretty much dismissed 100% of the sun being a major factor. I’m sure the astro-physycists will not be happy with the pro-GW view and will re-double their efforts to prove otherwise. Are astro-physicists more dishonest than cilmate researchers?

    The reason I was mentioning the Medieval Warm Period and the Little Ice Age (if they even existed) as important to me was that we have seen some wild fluctuations in the earth’s temperature in those periods while the CO2 atmospheric concentrations was a “constant”.

    My problem was that even though I had previous doubts in the GW theory, it had been settled by scientists with proof. That’t why I supported Kyoto. My research (limited to about 25 hours but much more than 98% of the population) in the matter proves otherwise. To me, both sides have valuable arguments.

    I really don’t think we should dismiss any arguments. The character assasinations of honest scientists should stop. I think that both sides is guilty of this. Should we give more weight to a study financed by Greenpeace or Sierra than one financed by Shell or Exxon? Shoud we dismiss both studies as being biased?

    Raypierre has not convinced me but he has taken me more towards the neutral ground.

    [Response: I’ll be happy if I merely convinced you to do more reading. As for astrophysicists and solar forcing, I want to clarify my statement a bit. I only dismiss solar forcing as a major factor in the 20th/21st century climate signal. Based on physical modelling taking into account measured and astrophysically plausible variations in solar spectral luminosity, and on consistent physical models of the response of he climate system to solar forcing, you can’t explain away the 20th/21st net warming trend with solar effects. I don’t think there are any astrophysicists that would disagree with the estimates being used for luminosity variations, not even Baliunas. It is the purely empirical claims of close association between solar activity and climate (generally coming from Fries-Christenson and Svensmark) that should be discarded, primarily for the reasons documented in Damon and Laut’s paper. As for the broader view of Holocene climate change, the Medieval Warm is a rather diffuse event and so ill-defined that it isn’t very easy to use it as a test of anything. However, something very clear and real was happening during the Little Ice Age, which demands explanation. The only viable mechanisms on the table for that have to do with solar forcing, but it has so far proved very difficult to get a sufficient cooling out of any astrophysically plausible luminosity change. Understanding the LIA is difficult because we are lacking most of the direct observations needed to answer the major questions. For the 20th and 21st century we have many more direct observations of the Sun, the clouds, and so forth, and are on much firmer ground with regard to saying what the Sun is or isn’t doing to climate. –raypierre]

    Comment by SC — 22 Apr 2006 @ 10:19 AM

  34. Re. #32

    I have never claimed to be an expert, but I’m trying to learn enough on my own rather than rely on journalists ,TV commentators and politicians. This blog was originally about media inflation.

    In Engineering, you get courses in combustion, Geology, physics , heat transfer ,liquid mechanics etc. What I was really trying to say is that in general, Engineers have a “prove it” mentality which is not always a good thing. Just ask my wife. I do agree that Engineers tend to move beyond their area of expertise.

    But I never came here as a climate expert. I believe I came here with some questions and a few doubts.

    [Response: That will always be welcome here ! I only wish I had the time to respond more fully, and in more detail. –raypierre]

    Comment by SC — 22 Apr 2006 @ 10:55 AM

  35. I agree that although scientists in general are rarely climatologists, we do have a better perspective on the scientific evidence. Most of us know basic physics, and we’re well versed in the scientific method and the criteria for study.

    Also, climatologists don’t live in a vacuum! They need, e.g., mathematicians. That’s how I’ve become convinced of the AGW hypothesis; I don’t know much about atmospheric chemistry, but you have to get up pretty early in the morning to fool me with *numbers.* I first took the AGW issue seriously when I discovered that Soon & Baliunas had published a paper disputing the paleoclimate record. Dr. Baliunas’ reputation was sufficient to cause me to *doubt* global warming! So, I investigated carefully, and I can tell you for sure, that paper is faulty on so many levels, it’d be funny if it weren’t such fuel for contrarians. And you don’t have to be a climatologist to know that.

    I’ve noticed this consistently: papers denying global warming *often* have fundamental errors in data analysis. Papers supporting the AGW hypothesis consistently adhere to high standards of mathematical analysis. Numbers don’t lie — people do.

    Comment by Grant — 22 Apr 2006 @ 11:32 AM

  36. An aspect that hasn’t been addressed here (as far as I can tell) is the role of Nature in all of this. It would be interesting to compare the first draft (or abstract) submitted to Nature with what ended up getting published. Prof. Myers – how about it?

    Even if few changes were made, reading the abstract suggests that the thing that made it “Nature worthy” was the 11 degree finding. I’m certainly not suggesting that it shouldn’t have been published, nor am I suggesting that the 11 degree finding is being hyped out of context – after all the title was “Uncertainity….” which should have led to some pause by journalists.

    However, all that having being said, what Nature and Science decide to publish or not publish seems a bit idiosyncratic and somewhat geared to it’s potential publicity or “splash” value. For example, they have their own press releases, embargoes and the like all of which add to a certain “breathless awaiting” of each issue. I think Chris Christensen is on the money when he says “a little hyperbole in a press release is to be expected — the critical moment is whether the science is backed up.”

    Getting published in Nature or Science demands more than just cutting edge science – some hype is demanded by the journals themselves. In fact, without it the editors will ding the manuscript without even sending it to review. So you more or less have to come up with something edgy to start with.

    After reading the paper I really think the authors did an excellent job of presenting a fair account and of keeping the hype to a bare minimum.

    Comment by Bob King — 22 Apr 2006 @ 11:33 AM

  37. RE #31 At last a post that I can agree with!

    Newspaper depend on their sales. If the paper does not sell it won’t get published. In order to sell it must be ENTERTAINING. That is why they report the unusal. They don’t report “dog bites man.” They report “man bites dog.” And that is why they don’t report that “climate sensitivity is probably in the middle of previous predictions” and do report “Climate sensitivity may be twice scientists’ previous estimate.” Which story would you read? Don’t shoot the messenger. The journalist can only get published what his editor will accept, and that is what his readers find interesting. The sooner scientists realise this the better.

    If you think that there is a danger from global warming, then the press releases must emphasis the dangers, otherwise the public will not get to hear the real facts. But it is worse. It seems that Gavin does not wants the public to hear the facts. he wants to censor what the public should read. If the model says that an 11C sensitivity may be possible, he does not want the public to be told. He seems to believe that James Annan’s 3C is the correct value. No other figures may be published.

    But the 3C is just his opinion based on the fact that most models come up with that value. That is no guarantee that it is correct. In fact, since there is such a large range of results from the models it is almost certain that it is wrong! But let’s assume that it is the most likely rise.

    If my house caught fire, how much of it would be destroyed? Perhaps the chimney will catch fire and I will have to pay a sweep to clean it out. Perhaps a chip pan will catch fire and I will need new kitchen units. Perhaps the electric blanket on our bed will ignite and all the upstair bedrooms will be destroyed, or perhaps teh house be burnt to the ground. The most likely case is that it will not be totally destroyed. So should I only insure it for half its value? Of course not. I want to know the total value of the house so I can insure against that. And I want to know what is the maximum climate sensitivity so I can bring in global policies to prevent that happening. I, as a member of the public, need to know that there is a possibility of an 11C rise. I don’t want scientist hiding that information from me because I might be alarmed.

    Pat Neuman showed us his press release. It is in fact inaccurate. He describes what is happening as rapid climate change. That is wrong. The last instance of rapid climate change was 10,000 year ago at the end of the Younger Dryas, when the temperature in Greenland leapt by 20C within three years [Richard Alley, The Two Mile Time Machine] That is rapid climate change, and that is fact not a climate model.

    It is really about time that climate modellers who are posting on this blog came down from their ivory towers and had a look at the real world. Read Pat Neuman’s press release and see what the physical world is like. Read Mark Serreze when in 2002 he was asking if we had reached a tipping point See,

    Meanwhile forest fires have raged from California to Alaska, and from Portugal to Greece. Last month they were raging in Victoria Australia. In Africa Mount Kenya and Kilimanjaro are losing thair ice caps

    In the radio program, on which this thread is based and you can hear by clicking on the button on the right of the web page, Dr Tim Lenton says “We don’t literally have to start reducing emissions tomorrow” That was totally misleading, far worse than saying that an 11C rise might happen sometime in the future.

    The problem is that the models are wrong, and Lenton is basing his ideas on the models rather than the facts. The models can’t reproduce the rapid climate change at the end of the Younger Drys, nor can the models reproduce the lapse rate in the tropics measured by radiosondes and MSUs. The data has been massaged to make them fit the models, but then the new figure are completely incompatible with the effects of aerosols which it is purported are causing global dimming. Aerosols are the only way global dimming can be made to match the models. The modellers should not be allowed to have it both ways. If the middle troposphere is warming it is either as predicted by the models or because of aerosols not both. Every time the models fail to match reality, it is reality that is changed to fit the modesl.

    I have already explained here that the models are using classical thermodynamics to calculate the effects of radiation, rather than quantum mechanics. What more can I say that in order to save the planet from the scientists?

    [Response: Alastair, please, no more about Kirchoff’s law and how all the radiation models are wrong. We’ve been through all that before. –raypierre]

    Comment by Alastair McDonald — 22 Apr 2006 @ 11:34 AM

  38. Regarding #24, the remark by Ocean on scientists being more “responsible” when emphasizing the most probable outcomes:

    I would say that it would actually be irresponsible for scientists to only emphasize the most probable outcomes and fail to explore the more extreme possibilities. One must take care to label the extreme possibilities as such, but these extremes are very relevant to policy decisions. Even assuming we are assigning probabilities correctly (very dubious in itself), the usual use of probabilities of outcomes in things like cost-benefit analysis assumes an aggregation of harms across many, many similar decisions, in some of which cases things turn out very badly, but in others of which things come out not so badly. In the case of global warming, all our eggs are in one basket, as it were, so the chance that something really, really bad happens needs to be weighed very seriously. The study is very significant in that it forces modellers to think more broadly about what their parameterizations can do.

    Comment by raypierre — 22 Apr 2006 @ 11:45 AM

  39. #37: Thanks Raypierre. I agree with you that the extreme cases should also be explored by scientists and that it would be irresponsible to do otherwise. . I simply offered “responsible” as an alternative to “conservative.” I don’t see scientists as conservative because that defeats the purpose of looking for truth.

    Comment by ocean — 22 Apr 2006 @ 12:09 PM

  40. If you want to comment on the WSJ editorial it’s open.

    Comment by Mark A. York — 22 Apr 2006 @ 12:47 PM

  41. To Rasmus’ comment in #26, scientists ARE getting intensive media training, unfortunately they are the Michaels and Baliunii of the world.

    On a more serious note, the problem for journalists (if they know what they are doing) in reporting a range of results for climate sensitivity is that the low end is ho-hum, but the higher end is more interesting. BUT THEY ARE RIGHT! The high end is where the threat is and the correct approach is to weigh probability by threat.

    For example, even though the threat of asteroid impact is low, the threat is so large that it has to be taken seriously.

    Let us look at a similar problem that has been much featured on this site, cyclone intensification. Assume for the sake of argument that there is an even divide on whether this is happening due to AGW. One approach is the “more study is needed”. That is traditionally the approach of scientists. Policy makers have two choices, “ignore the threat and in 50% of the cases we are right, and in 100% of the cases we are retired from office”, or “this is a serious issue, and because the large losses associated with what would happen if this were correct, start taking action now”. In the second case, would it be responsible, or irresponsible for policymakers and journalists to emphasize the extreme in their reports?

    Which brings us back to climate sensitivity. (Note: even the sensitivities in the two new probabalistic estimates are strongly skewed to the high side). What is interesting to most people who read newspapers is not the narrowing of the range (still pretty much Arrheniuslike) of probability for climate sensitivity, but the distribution and the associated risks for themselves. They denialists make use of this by emphasizing and exaggerating monetary costs of action. The traditional response has been that there are many no/low cost responses, but this is a losing position, because what the public does is to weigh high cost vs. low cost, average them together and gets medium to serious expenses…. This, of course, ignors the costs associated with doing nothing, but they are in the future, and what has the future ever done for us.

    How should this range be weighed by those, including the public, for the purposes of action or inaction? I would submit that it would not be unreasonable to use a sharply increasing exponential weighing and I further submit that this would restore a needed reality to the debate.

    Comment by Eli Rabett — 22 Apr 2006 @ 1:21 PM

  42. While I can appreciate the wish for scientists work to be portrayed faithfully, I ask what is so wrong with hyping up climate change predictions. Yes the high end estimates may not be the most likely to come to fruition, but they are the most likely to get people to start acting. We can all sit around arguing over whether global temperatures will rise 2 or 11° by 2100, but lets not wait til then, doing nothing, to find out who’s right. If, by allowing the press to report that a change of 11° is likely within many people who are alive todays’ lifetimes, people become more aware of the issues and the dangers of AGW and start to take action, start to insist that Bush listens to those urging him to join Kyoto, what harm does that do?

    Comment by Jinni King — 22 Apr 2006 @ 2:11 PM

  43. Re #28 (Rasmus),

    There are definite cultural differences between the disciplines of science and journalism. Some of the problems that occur when information is exchanged between simply cannot be avoided.

    Here’s a couple
    1. Scientists enjoy nuance (on the other hand statements) Journalists need clarity (boil it down into one sentence)
    2. Science is conservative and moves cautiously. Journalism needs quick results and eye catching headlines.

    I think that every science journalist should have training in science. I know that some journalists will read this and get angry, but I think it’s important to understand how scientists think.

    I also believe that scientists should get media training. If not, they will make mistakes and inevitably come away thinking, “Well, why did she write that?”

    Much of this has been hashed over in exquisite detail by Deborah Nelkin, a researcher at NYU who passed away a couple of years ago. I would really recommend her book “Selling Science: How the Press Covers Science and Technology.” Link:

    Comment by Paul — 22 Apr 2006 @ 2:15 PM

  44. I think the 11-degree variant is of such dimension that the media consumer recognizes it is significant; to a reader the reaction is almost visceral; the body realizes 11 degrees would alter the conditions in which we live.

    If the Stainforth study is replicated one decade from now based on ten more years of data, we might find a need to augment that 11-degree distance.

    It is noteworthy that good science continually attempts to restrain exaggeration.

    Yet, while the Stainforth article offers much for further examination, the BBC linked material has value in a different realm. As a former livestock raiser, and forest replanter, I observed one BBC graphic captioned ‘Drought or flood’ is a perfect illustration of the error of oversimplification, as I thought immediately of alternatives to that binary, such as soil compaction, trampling, decreased vigor offering susceptibility to fungal infection, as the tree is denuded and there is livestock nearby. Science is complicated; it makes it worthwhile to pay well for bright people to write the press releases. Beyond fact, there is politics, and other contexts abound; indeed, as the author alludes, Gallileo per force needed to have considerable pluck, as his disgrace lasted a long time.

    Comment by JohnLopresti — 22 Apr 2006 @ 2:43 PM

  45. Re #37. I would go farther and say that the plausibility of the high sensitivity end is the single most important scientific issue facing us at this point. The potential for surprises presumably rises dramatically as a function of sensitivity. is a nice way of generating candidate high sensitivity models for more detailed analysis. How the distribution of sensitivities that they generate should be publicized is a separate question.

    Comment by Isaac Held — 22 Apr 2006 @ 2:55 PM

  46. Re. #41

    “I ask what is so wrong with hyping up climate change predictions”

    For the same reason that it would be wrong to downplay it or ignore it if it exists. The truth is the truth whatever it is and people deserve to know it. You mention Bush for Kyoto but you believe that the exact same tactics be used to sell Kyoto that he himself used for the case for War and WMDs.

    Don’t you find it a little strange that the United Nations believes that there is 100% chance that the temperature will increase in the next century? To me, it would have been more credible to say that the range will be -1.0 to 5.

    Let me ask you something. If the earth starts unexpectedly to cool down in the next dozen years that wipes out all the previous gains, should our response be to start pumping more CO2 in the atmosphere to limit it?

    The green house effect was well known in the 70s. Did any scientists say “don’t worry about the global dimming alarmists, the CO2 we are pumping will take care of the problem”?

    the reduction of fossil fuel consumption should be sold to the public for the real reasons. Whatever they may be. If it happens that CO2 causes no harm – then let it be. I agree that it this would not be a good situation – since the guilt factor in people would drop.

    I am no fan of GW Bush but I tend to agree with him on Kyoto. Why close plants in the US and move them to China and India (who don’t have to reduce their emissions). The net benefit to the Earth will be 0. Not only that, Kyoto will increase the long distance transportation of hazardous chemicals (on the oceans) as these will get produced more and more in countries who don’t have to reduce their emissions. The demand however will not geographically change.

    Simply moving production of goods to countries much further than where the demand is only acts to increase the need to transport them a longer distance – which in turn also burns more fossil fuels.

    Comment by SC — 22 Apr 2006 @ 3:12 PM

  47. I got the lead online comment albeit with a copyediting issue. The others are of the same sort Ray noticed before for the mostpart.

    Comment by Mark A. York — 22 Apr 2006 @ 3:13 PM

  48. Re#44: I wouldn’t say it is the “single most important scientific issue..” In fact I don’t think the lay person would consider AGW “more imporatnt” than say, Alzeimers, AIDS or cancer research. The potential for surprises increases as a function of sensitivity, but even “not so alarming” trends in warming can have long standing negative effects on reefal communities, continental aridity, etc. While I think worst case scenarios are well worth analyzing, I don’t think it is the one thing we should focus on. Because this quickly begins to sound like a Hollywood horrorr flick to the casual reader. But maybe I read your post incorrectly.

    Comment by ocean — 22 Apr 2006 @ 3:33 PM

  49. Re #45: Sorry, I meant the single most important issue in global warming research. (I am used to just corresponding with by climate modeling colleagues.) The potential for surprises is already much greater at the high end of the canonical range as opposed to the low end. The ramifications of even higher values is truly frightening to most of us, so evaluating claims that the probability of such values is non-trivial needs to be at the top of our list of priorities.

    Comment by Isaac Held — 22 Apr 2006 @ 4:32 PM

  50. Our alarm over alarmism is all well and good. Neither scientists nor journalists communicate perfectly, and all should work to improve. But no matter how well they do, skeptics will always be able to cast doubts and aspersions.

    And then the skeptics’ simple conclusion goes unchallenged: that it is not worth spending trillions of dollars to decarbonize the world economy. This conclusion is often only implied, other times mentioned offhandedly, as if it is inherently obvious.

    IMHO we must not let that huge conclusion go unchallenged. Not ever. (For one thing, it’s alarmist!) I know that is not RC’s charter to discuss energy technology, economics, or policy, but we can at least point to those who do it well, and arm ourselves with the main points. If you can excuse a shameless plug, Amory Lovins, a physicist, has been doing just that for us all since about 1973, and has data and analysis at the Rocky Mountain Institute website, .

    How much money would we save by decarbonizing? How energy efficient can we become, how fast, and how profitably? What is the best array of renewables? How many other problems would we solve by decarbonizing? How healthy, wealthy, safe, and secure do we want to be?

    Skeptics who advocate free markets should at least agree to end all fossil fuel subsidies. But they are rarely mentioned, even in the WSJ cited in #26.

    You are absolutely right that we shouldn’t be alarmist. But couldn’t we be “solutionist”?

    Comment by Mark Shapiro — 22 Apr 2006 @ 4:45 PM

  51. Thank you Isaac Held. That was very helpful to me. I am an earth scientist and a climate scientist to be :)

    Comment by ocean — 22 Apr 2006 @ 4:52 PM

  52. AGW less important than Alzeimers to average person? I don’t think so and I sure hope not. I think people who realize there is no real debate about its reality consider AGW one of if not the single most important global challenge.

    Eli: thanks for your comment about the relevance of high end sensitivity, be it less likely than low end or not. You are totally correct that severe, low risk danger is deserving of greater coverage than less severe but more likely danger. Who among us would gamble everything we have, including health and children, with a 5% chance of losing it all?

    JohnLopresti, #43, I mostly agree that sensationalism will more likely mobilize, but there is in fact a very considerable down side. If you succeed in mobilising people with a prediction of 11C warming, great. But what will happen when new research gives great certainty to only 4C warming? It just happened: I wrote “only 4C warming” as if it is not so bad.

    The real challenge that science faces here, is getting across the message that 3C is hugely problematic! The new critical message has to be about the possible ramifications of “only” 3oC warming. Reef death, more intense storms, droughts, extinctions, the public needs to learn that there is a lot more going to go on than warmer weather. Emphasize that we are now matching the warmest climate seen in the glacial record. 3C warming puts us in a climate not seen in millions of years. These are simple, factual statements that will resonate with the public.

    The other advantage of focusing here, is that this is the next point of attack for the septics. “What warming?” is in its death throes, in the next one or two years Bob Carter’s “it stopped in 98” crap will be back firing. The focus these days is “5C is a ridiculous exaggeration”, that argument should be dropped and we should focus on what 3C warming really involves, heading them off at the pass.

    Comment by Coby — 22 Apr 2006 @ 5:01 PM

  53. The fact that Myles’ results were misrepresented in the press only happened, and in one sense only matters, because there are two fairly polarised ‘camps’ regarding global warming.

    That there should be two camps at all is on the face of it extraordinary. Are there two camps regarding Hubble revelations, WHO strategies to eliminate polio, or new hip replacement prostheses? There is discussion, but no polarisation or war of words.

    Of course it’s not extraordinary at all because the emissions reduction debate is is many ways a metaphor for the debate on world poverty. The solutions for both problems that can at present be envisaged engender deep, if often unmentioned, fears. For if ‘they’ are to have more, we must have less, and if the supply of resources is more limited than previously thought, our share is smaller still. Hard to come to terms with if you have to reconcile winning the popular vote and your personal ethics.

    I am a moderator on one of the Oxford Climate Prediction forums, where we are also slowly learning to be more circumspect in some of what we say than previously seemed necessary.

    Comment by Maureen Vilar — 22 Apr 2006 @ 7:03 PM

  54. In 37. Alastair McDonald wrote: Pat Neuman showed us his press release. … He describes what is happening as rapid climate change. That is wrong.


    I said Rapid Global Warming is Happening Now (10/30/2003)

    Ancient Climate Studies Suggest Earth On Fast Track To Global Warming
    by Staff Writers Santa Cruz CA (SPX) Feb 16, 2006

    Human activities are releasing greenhouse gases more than 30 times
    faster than the rate of emissions that triggered a period of extreme
    global warming in the Earth’s past, according to an expert on
    ancient climates.

    “The emissions that caused this past episode of global warming
    probably lasted 10,000 years. By burning fossil fuels, we are likely
    to emit the same amount over the next three centuries,” said James
    Zachos, professor of Earth sciences at the University of California,
    Santa Cruz.

    Comment by pat neuman — 22 Apr 2006 @ 7:13 PM

  55. To ocean (what a nice handle:) IMHO you are drawing a false set of analogies. There is a major difference between AGW climate associated risks and risks of Alzheimers, AIDs, etc. The latter are personal risks, the former is global. Bird flu, if it ever jumps into direct human to human spreading is more of a global risk because of the rapid mechanism by which flus propagate.

    I absolutely believe Hegerl et al and Annan and Hargreaves. I also believe that the data they analyzed are not complete and do not include the “unpleasant surprises” that may await us. The further the climate system is pushed into terra incognita, the less trust one can put into these probabilistic analyses and climate models.

    As I said in a previous life: Worry

    Comment by Eli Rabett — 22 Apr 2006 @ 7:15 PM

  56. There is a big gap between what scientists know & what the public makes of it (assuming the public even tune into the science news).

    Scientist: “11°C? If that’s for real, we’d all be double dead within x number of years, given current rates of xyxy.”

    Public: “11°F [<=C]? Well, it usually varies more than that within a 24 hour period. What’s the big deal?”

    Another problem (correct me if I’m wrong) is sensitivity is sort of like a rate, and is only one consideration in the total picture, certainly not the total picture. My thinking is, “unsafe at almost any sensitivity.”

    It’s like we’re all in this train which increases its speed a certain amount per amount of coal added, but we don’t know exactly how much; we only have a range. It says nothing about people rushing to stoke the engine with more and more coal, or how much actual coal is added (thus the actual range of speeds to expect), or the possibility of a precipice with bridge out up ahead (runaway GW), how dangerous that might be at various speeds, entailing greater or less number of deaths, or how far or close that precipice is, which we don’t know either (except we have some fossil evidence of train wrecks in which 90% of life died, so we know it could be bad). We also understand that even if we slam on the breaks (totally stop emitting GHGs), we’re going to slide forward for some time — maybe even over that precipice.

    But then people would think, “I’m going to bail from this train,” so maybe SPACESHIP is a better metaphor, & we’ve got engine problems & may be self-destructing, like Apollo 13 — “Spaceship Earth.” And Tom Hanks would really like to solve this problem in a cool-headed way, except naysayers & denialists are harping in his ears, “We’re not 100% sure we’re going to self-destruct until we actually do so. It’s just not a big problem yet.” And the people in the back cabin don’t even know there’s a problem, because they don’t even tune into science news.

    I hope all this sounds alarmist enough to get people to reduce their GHGs. I mean, what will it take? Nothing seems alarmist enough. Nothing seems to resonate with the general public. I guess science is just too boring — even an 11°C sensitivity. A big public yawn.

    Comment by Lynn Vincentnathan — 22 Apr 2006 @ 7:27 PM

  57. Wow, I started something :) I am plenty worried about global warming. I am on the same page with you guys. I wasn’t trying to minimize the importance and panic-worthiness of AGW. But if you ever had to care for someone with cancer, AIDS or Alzeimers, you might want to fund medical research over environmenetal research. We have to be healthy and alive to resolve environmental issues. However, it is also a fact that most of these diseases are caused by human induced environmnetal issues. Don’t get me wrong. I am a publishing, grant getting ocean scientist [hence the handle] and have strong feelings about AGW. I am all for AGW research from the most mundane scenario to the most extremist one. It is extremely important for humanity and our palnet. No argument there. And as I said I am plenty worried.. But, on a personal level, if I get Alzeimers, how can I continue my research? How can you ? :)

    Comment by ocean — 22 Apr 2006 @ 8:07 PM

  58. I’m sorry. I have to ask what does IMHO stand for?

    Comment by ocean — 22 Apr 2006 @ 8:11 PM

  59. Given your public concerns with Stainforth 2005 such as:

    we were quite critical of their basic conclusion – that climate sensitivities significantly higher than the standard range (1.5 – 4.5ºC) were plausible

    would you mind saying when those opinions will be appearing in the Correspondence section of Nature or if you have submitted letters to Nature detailing those concerns? Thanks

    [Response: David, I neither have time nor the interest in writing official replies to every paper I may have some issue with and to do so without having some new analysis would most likely be a waste of time. This topic is already well populated with papers that are tackling the issue more constructively and I’m happy to sit back and see how it unfolds. – gavin]

    Comment by David Stockwell — 22 Apr 2006 @ 8:25 PM

  60. Ocean,

    IMHO: While it sounds like a medical plan that doesn’t actually cover illnesses, it means “In my humble opinion.”

    Comment by Mark A. York — 22 Apr 2006 @ 9:35 PM

  61. re:60. Once again, this gets back to the understanding, or in this case the apparant lack there of, of the scientific method. It is sad to see so many skeptics who reflect a lack of that basic, fundamental understanding. Science is about hypotheses and theories, gathering evidence and data, conducting experiments or models to test those hypotheses and theories, generating new hypotheses from those tests, subjecting those results to peer-review, and others repeating those experiments. Global warming research follows the scientific method. If scientists followed (A) and were “deliberately misleading” the public, it would not follow the scientific method at all. The process would show that through peer-review and the inability to repeat the experiments. As for (B), if they are wrong, again the peer-review process and inability to independently repeat the experiments would show it. Since the scientific method works, neither A or B apply.

    It is noteworthy that relatively few of the skeptics arguments appear in peer-reviewed journals simply because their “results” can not be repeated. Nor have they proposed (or tested) valid theories which can explain past or recent trends.

    Comment by Dan — 22 Apr 2006 @ 9:54 PM

  62. It seems to me that many readers of RC, especially readers of the present and recent threads, will be interested in the Andrew Revkin piece that’s just been posted by the New York Times at the top of tomorrow’s Sunday “Week in Review” section ( It’s called “Meltdown: Yelling ‘Fire’ on a Hot Planet” and there are links to a graphic sidebar and a video sidebar. In part Revkin responds specifically to the Lindzen WSJ piece. I hope I find out through RC discussion what climate scientists think of Revkin’s article overall. Is it, for example, too balanced in the sense of crediting foolishness in a phoney balance with fact — i.e., in the sense of that science-journalism “balance” dynamic that RC has criticized? I believe I recall that Revkin has drawn high marks at RC in the past.

    Comment by Steven T. Corneliussen — 22 Apr 2006 @ 10:37 PM

  63. In my humble opinion, (IMHO) a rather good list of these abbreviations in an unlikely place

    Comment by Eli Rabett — 22 Apr 2006 @ 10:51 PM

  64. Thanks Eli. I am new to blogs and posting messages..

    Comment by ocean — 22 Apr 2006 @ 10:52 PM

  65. #60, In the struggle to successfully predict the future, those who project will only look back and see if their calculations were correct, in the process of making projections only time can confirm a particular theory,. There should be no restrictions on theories and announcements through various medias, the future is very unforgiving in this domain, exactitude is the goal, perfecting projections is hard work. The lay person need not be confused, the direction of our world climate is nothing but warming, the big question remains: at what rate this warming? To have some confidence in the work of climate scientists, look back, say to the 80’s, research those who predicted todays climate accurately, and see what they have to say about the next 20 years.

    Comment by wayne davidson — 22 Apr 2006 @ 11:28 PM

  66. Re #60

    can see no other reasonable interpretation of these statements than that the scientists believe their experiments show we’re in much more trouble over global warming than previously thought

    Skeptick, you have gone wrong already, this is not the correct paraphrase at all.

    The scientist believe, and said quite clearly, “their experiments show tha it is possible we’re in much more trouble over global warming than previously thought”

    These qualifiers are important, but unfortunatley they are the first thing to get chopped when stuffing things into sound bites. But that is not evidence of any wrong doing on the part of researchers. It’s not even evidence of anything worse than irresponsibility and/or sensationalizing on the part of the journaists either (ie not evidence of conspiracy)

    [Response: Note: I deleted the original comment 60. Skeptick is evidently just another of Graeme Bird’s numerous pseudonyms, or at least a post by somebody doing a good imitation. These are just trolls, and attempts to disrupt the dialog. Don’t take the bait, and expect the few such things that slip through to disappear once one of us notices. –raypierre]

    Comment by Coby — 23 Apr 2006 @ 12:31 AM

  67. Re #43: “It is noteworthy that good science continually attempts to restrain exaggeration”

    This is a very astute observation indeed. I would add that good scientists do not publish results until they understood all caveats, especially instabilities in their models. For example, the Stainforth et al. article states in “data quality” section:

    “Finally, runs that show a drift in Tg greater than 0.02 Kyr21 in the last eight years of the control are judged to be unstable and are also removed from this analysis.”

    Also, from the same source:
    “Most models still maintain a temperature of between 13 and 14 °C, however some get colder – these are not stable and the heat flux calculated in phase 1 was not correct to keep the model in balance.”

    These statements pretty much nullify results of the whole article IMO – it looks like the data were filtered in favor of desireable result – GW.

    Similar situation is with the Annan and Hargreaves article. They base their analysis on an assumption that all objects in their ensemble are independent. This assumption was not quantified in the article, they assumed this as obvious. Unfortunately, all their objects are based (in one or another way) on linear concepts and perturbations near an alleged global equillibrium, while even superficial inspection of paleoclimate data (like ice cores) makes it quite clear that the climate-bearing system is continuously on the move, it oscillates back and forth like an relaxation generator, and therefore is never in static equillibrium. As result, multiplying outputs from predominantly wrong models does not create any more overall confidence.

    – aap

    Comment by Alexi Tekhasski — 23 Apr 2006 @ 1:30 AM

  68. Re #67: “I would add that good scientists do not publish results until they understood all caveats, especially instabilities in their models.” Anyone with a Science or Nature sub could tell you that this isn’t true. Science would have awfully hard time making progress using such an approach. Even relativity and evolution still have unresolved caveats, and no string theory paper would ever have seen print.

    “Unfortunately, all their objects are based (in one or another way) on linear concepts and perturbations near an alleged global equillibrium, while even superficial inspection of paleoclimate data (like ice cores) makes it quite clear that the climate-bearing system is continuously on the move, it oscillates back and forth like an relaxation generator, and therefore is never in static equillibrium. As result, multiplying outputs from predominantly wrong models does not create any more overall confidence.” This is utter nonsense. If you have a dislike for the conclusions of climate scientists, just say so. Resorting to multi-syllabic gobbledygook just wastes bandwidth.

    Comment by Steve Bloom — 23 Apr 2006 @ 2:36 AM

  69. Re #69 “This is utter nonsense … multi-syllabic gobbledygook…”

    I am truly sorry that I was not up to your educational level when trying to express myself in such a confined space as webblog. If you could be a bit more polite and ask me which part of the above paragraph you do not understand, maybe I would find some time to educate you (but now it is very unlikely) :-(

    Re: “Even relativity and evolution still have unresolved caveats, and no string theory paper would ever have seen print.”

    Anyone with practical experience in personally contributing to advances in Physics or Mathematics would immediately realise that the above statement lacks so much of truth that in common language is called “utter BS”. You failed to realize one important thing: in a good science a researcher clearly states his assumptions upfront, and does not state conclusions without proper reference to underlying assumptions. As far as I see, this discipline is severely lacking in the field under discussion.


    [Response: Then you obviously haven’t been reading the scientific literature, or are less than honest about what you have seen there. In fact, the paper in Nature is a model of clear statement of assumptions, procedures and objects, within the space constraints of a Nature piece. As far as I can see, you are simply making unfounded assertions in the hopes somebody will be fooled. It’s bizarre — more than bizarre — that a person who has defended Zbigniew Jaworowski’s gobbledegook alchemical claims about ice core CO2 , as you have in posts elsewhere, would think he had any credibility in criticizing climate science. As for the phrase “multisyllabic gobbledegook,” yes, that’s perfectly descriptive what you wrote at the end of your post. Wish I had thought of that phrase myself, but I was sure one of our readers would find an appropriate response. –raypierre]

    Comment by Alexi Tekhasski — 23 Apr 2006 @ 3:18 AM

  70. Re #59: David, you seem eminently well-qualified to submit such a letter yourself, having just had a paleoclimate review article published in a leading Australian geological journal: ; see page 14. I see that on page 15 there is an interesting related commentary by the esteemed editor of the journal. Anyway, please let us know how Nature responds.

    Comment by Steve Bloom — 23 Apr 2006 @ 3:56 AM


    Stuff like this.

    In the USA the political right are so against action to combat climate change because it appears to somehow appear to be communist in nature, anti freedom and individual restrictive and hence against the seemingly free market economy that the USA has embraced since the end of the 2nd world war culminating in such neurotic/paranoid behaviour as being labelled a left wing conspiracy.

    I also imgaine that these right wingers (neo cons I believe they are known as) are also very religious in nature (or appear to be) and they carry a lot of power in the USA and hence considering the evolution vs creationism debate that is raging over there at the moment getting action on climate change seems to be almost impossible in the current or by a future republican administration.

    I also imagine that this is the reason why there has been such a lot of debunking of climate science since the problem has become mainstream with the fossil fuel industry being represented at every turn in the fight for cuts in greenhouse gases that as yet we have none !!!!

    The USA seems to be a country with a heady mix of “totally at odds” poltical agendas and views. Republicans really are right wingers who appear to believe in some very odd things but carry great power. Not sure about the democrats but I guess they must be the liberals/left wingers that might do something about GG emissions and hence appear to be feared by the right.

    Comment by John Hughes — 23 Apr 2006 @ 6:22 AM

  72. re: 70. No! A good scientist makes hypotheses, not assumptions. He/she then proceeds to test those hypotheses.

    Comment by Dan — 23 Apr 2006 @ 8:43 AM

  73. Mark A. York: I did at first think IMHO was some medical term :) Thanks for the clarification…

    Comment by ocean — 23 Apr 2006 @ 9:24 AM

  74. While I agree with Dan, there are assumptions that go into any model. Even plate tectonics had to assume the Earth is not expanding when it was first developing as a theory. Now I think we know for a fact that the Earth is not expanding and that strengthens plate tectonics as a theory. [For the skeptics out there: It is still a theory, though sea floor spreading is a fact, because the exact machanisms driving plate motion need to be better understood]. I think good scientists explain their assumptions clearly and re-consider their assumptions when drawing conclusions. And their assumptions are hypotheses themselves which are/should be tested. And if the assumptions turn out to be true, then the theory/model based on those assumptions gains more strength/credibility.

    Comment by ocean — 23 Apr 2006 @ 9:40 AM

  75. I’m wondering if there isn’t some not very good assumptions to some of the models. But don’t know one way or the other.

    Comment by Lee — 23 Apr 2006 @ 9:58 AM

  76. Re # 62, Revkin in the NY Times:

    Revkin says “If the bad stuff doesn’t happen for 100 years or so, it’s hard to persuade governments or voters to take action.” But “bad stuff” is already happening, and it’s only going to get worse. Scientists are reluctant to claim “proof” of a connection of individual catastrophes to human causes, and yet the evidence of a connection is plausible and compelling, if not absolutely proven. Isn’t that enough to justify alarm?

    A plague of mountain pine beetles has suddenly devastated an area roughly the size of Great Britain in British Columbia. British Columbia hasn’t been this warm in 8,000 years, and the winters are no longer cold enough to keep the beetles in check. About half the living pine forest is already gone, and most of the rest is expected to be infested and die within 10 years. How much proof of a connection between CO2 and pine bark beetles do we need before we become legitimately alarmed, rather than have concerns dismissed as needlessly “alarmist”?

    In the waters around the U.S. Virgin Islands, as much as 40 percent of coral died in some reefs last year, and the coral that survived probably isn’t healthy enough to survive another hot summer, according to a U.S. Geological Survey biologist. Scientists can’t prove that global warming is the cause, because that would take decades of data and research. But the evidence of a connection between warming ocean waters and greenhouse gas increases is compelling and consistent with theory and observations. Certainly future ocean warming from increasing levels of greenhouse gases is reasonable to expect. Isn’t that reason enough to be legitimately alarmed?

    “We’re definitely seeing species going extinct because of climate change,” says Camille Parmesan, a conservation biologist at University of Texas. Lindzen would apparently dismiss her, and the hundreds of scientists whose work she bases her assessment on, as irresponsible “alarmists”. “This is bad news, not good news,” she says, …. It covers every geographic range, every taxonomic group. Zooplankton. Phytoplankton. Birds, frogs, butterflies. Mammals. Fruit flies. It’s overwhelming.” Isn’t it reasonable to be alarmed?

    It is irresponsible to dismiss this widespread concern as merely alarmist. It’s perfectly reasonable to be alarmed at plausible threats posed by unprecedented changes in the atmosphere and biology of the earth wrought by human activity, even in the absence of absolute proof of a connection between individual storms, extinctions, and economic catastrophes, and rising levels of CO2.

    Climate scientist Jerry Mahlman, a senior researcher at the National Center for Atmospheric research, says that each and every person in the world would have to reduce his and her per capita consumption of fossil fuels by 75 percent to keep additional future temperature increases to no more than 1 degree. “That’s a horrific number if you think about everything that you do…” he says. “We get all of this dirt-cheap fossil fuel. We burn it all up, we screw up the planet with greenhouse gases, warm up the planet, warm up the ocean, and therefore have many manifestations that are negative.”

    No wonder the skeptics would rather believe that greenhouse gases are nothing to fear. The solution to the problem requires an unthinkable sacrifice, and a change to our material culture that even a science fiction writer would have a hard time imagining. I think it is perfectly sane and reasonable to be alarmed.

    [Response: But one shouldn’t despair. If one can’t keep the warming to 1 degree, it’s still worthwhile to keep it to 2 degrees. If one can’t keep it to 2 degrees, it’s still worthwhile to work to keep it below 3 degrees. And remember, energy is far from the dominant component of the economy, and phasing in a 50 or 75% reduction in carbon emissions doesn’t mean a 50 to 75% reduction in energy usage — still less a 50 to 75% reduction in productive use of energy, given likely efficiency gains. People should have a lot more faith in the ingenuity of engineers and business enterprises, once given the right market signals. –raypierre]

    Comment by Michael Seward — 23 Apr 2006 @ 10:37 AM

  77. Are any of you aware of a secret meeting between Bush and Michael Crichton??

    The quote below is from this week’s New Yorker Talk Of The Town.

    “A book that the President did eventually read and endorse is a pulp science-fiction novel: “State of Fear”, by Michael Crichton. Bush was so excited by the story, which pictures global warming as a hoax perpetrated by power-mad environmentalists, that he invited the author to the Oval Office. In “Rebel-in-Chief: Inside the Bold and Controversial Presidency of George W. Bush”, Fred Barnes, the Fox News commentator, reveals that the President and Crichton “talked for an hour and were in near-total agreement”. The visit, Barnes adds, “was not made public for fear of outraging environmentalists all the more”. ”

    I thought this would be of general interest to posters and moderators on this site, so apologies if this is off-topic.

    To me it puts in rather depressing perspective the notion of how best to inform policymakers on the state of the science, as our president prefers ignorance, self-delusion and science-fiction.

    Not that it is likely to succeed, but I think some of the very distinguished scientists here should request equal time from the prez.

    Comment by Dan Allan — 23 Apr 2006 @ 10:50 AM

  78. Re #74: “While I agree with Dan…”

    I am sorry, while I applaud to the logic of the rest of your post, I can’t resist from mentioning one little discrepancy. You logically arrived to the statement that “their assumptions are hypotheses themselves which are/should be tested”. Aside the fact that the terms “assumption” and “hypothesis” are synonyms in first place
    you seem to disagree with yourself, since “Dan” markedly disagree with this parallel. So, what do you agree with Dan upon? ;-)

    Comment by Alexi Tekhasski — 23 Apr 2006 @ 10:50 AM

  79. Assumptions are not hypotheses. A hypothesis is an educated and testable potential solution to a scientific problem. Not all assumptions are testable.

    Comment by ocean — 23 Apr 2006 @ 10:57 AM

  80. Oops, used an html directive above… [fixed – gavin]

    I think what’s more disturbing than “alarmist” journalism, are the responses to it. The headlines, blurbs, ads for the programs that backtrack from the “alarmist” piece (and most people only have time for these, not the full story) then become: “GW not as dangerous as reported,” “Dangerous GW not likely.” Even “11 degrees of warming not likely” is problematic.

    First of all the public don’t understand what 11 degrees of warming means or entails, or 3 degrees, or 2. They experience more than an 11 degrees warming in a 24-hour period. We really depend on scientists, not headlines, to give us some idea about it. I think Mark Lynas is writing a book, SIX DEGREES, about what each additional degree entails in terms of effects and harms. That should help.

    Second, climate sensitivity is only one part in the whole picture. (Correct me if I’m wrong.) It says nothing about how much GHGs we’re pumping into the atmosphere, or the response of nature to the warming that causes either greater warming (reduced albedo effect) or more GHG releases from melting permafrost, etc. And once we’re on that positive feedback track for good, it’s just a matter of time (which climate sensitivity can help us understand, but only in part) before it gets really really bad. In my thinking climate sensitivity is “unsafe at nearly any level” (if we don’t reduce our GHGs).

    However, the debate swirling around sensitivity comes across as the whole enchilada.

    It seems to me there is no way we can be too alarming on this issue. I just don’t see people around me concerned enough even to, say, invest in a few CF bulbs & save money. I’ve told people that Green Mountain Energy provides wind power here for about 1 cent more per KWH & wind/hydro for the same price as fossil fuel electricity, but no one cares to switch. So, even if you tell people the world will end in 15 years if you don’t switch to CF bulbs & buy clean electricity, they just aren’t going to do it. Maybe they’re thinking, the problem is a long way off, surely scientists will solve it by then, so let’s get back to Saturday night planning.

    GW reporting is “under-alarmist” at any level of alarm you can conger up.

    Comment by Lynn Vincentnathan — 23 Apr 2006 @ 11:41 AM

  81. Climate scientists are surely suggesting that society does something regarding their conclusions from their research rather than just telling us their findings ?

    Comment by pete best — 23 Apr 2006 @ 11:50 AM

  82. Perhaps Alex hasn’t heard the slang definition of “assume?” Assuming anything makes “an ass of you and me.”

    Comment by Mark A. York — 23 Apr 2006 @ 11:56 AM

  83. re: 79. Precisely what I was going to say, ocean, thanks. Many assumptions are made without any testing at all. In science, hypotheses are tested.

    Comment by Dan — 23 Apr 2006 @ 12:12 PM

  84. #81: Can you elaborate please. I am not sure I understand what you mean.

    Comment by ocean — 23 Apr 2006 @ 12:17 PM

  85. Re 52 & 80: This is linked to my main gripe with the BBC programme. Early on they ask a load of people (kids? I yuned it at this point) what they thought the temperature rise so was and a lot said 2-3C, but the journalist pointed out to them that its 0.7C. There was no other context put to this figure.

    later on he kept referring to the sensitivity (or as I think he put it, “expected warming”) being “only” 3C. Though he repeatedly said that all the scientists in the programme thought that GW was a (big) problem, he never actually pointed out how bad 3C could be.

    I bet many people came away from that programme thinking it we can expect “only a 3C rise which probably won’t be all bad”.

    Also, ref the ideas about probability of an event multiplied by the seriousness of it, there is a measure for this isn’t there? I can’t remember the term, but do recall Martin Rees discussing it in his book “Our Final Century?”.

    Comment by Adam — 23 Apr 2006 @ 12:20 PM

  86. Just a silly note: every time someone uses “GW” to refer to global warming, it makes me think of “GW” as George W. (Bush, that is). So I’ve gotten in the habit of using “AGW” (I’ll be bold enough to include the “anthropogenic” part).

    Either way, “GW” is one of the world’s biggest problems today.

    Comment by Grant — 23 Apr 2006 @ 12:45 PM

  87. Grant: Do you mean George W or Global Warming is one of the world’s biggest problems right now? :) I’m sorry, it was too funny to pass up.

    Comment by ocean — 23 Apr 2006 @ 12:49 PM

  88. Re #79 and #83, “Many assumptions are made without any testing at all. In science, hypotheses are tested”

    You two are losing focus. I haven’t said anything about testability or other fine distinctions between assumptions and hypotheses. In #69 (formerly #70) I simply noted that a good science states assumptions it uses in a particular work. So, again, which part of this statement do you both disagree with?

    Granted, some assumptions propagate through paradigms of a particular science “by assumption”, usually and largely because the printed space is quite limited. This is true more than ever for climate science, where assumptions are piled upon assumptions and more assumptions and non-proven conjectures. I think the trouble in this field is that many younger folks simply forgot how shakey their whole foundation is, and take old doctrines at their face (numerical) value, which was canonized through years and years of repetitions by popular science articles. I see the problem when rare author (if any) mentions the chain of assumptions (and associated error bounds) when some result about climate is stated in his/her article. Obviously, regular folks and press have not enough intellectual abilities to discern and dig out all that chain, and make a really informed judgement on the importance of the result. I see that as a fault of climate scientists who forgot to make those clarifications, especially if the work contains sensational claims.

    Comment by Alexi Tekhasski — 23 Apr 2006 @ 1:18 PM

  89. Ok Alexi.. Can you be specific at least about the few assumptions that these GW models are shakily grounded on? I am asking this genuinely. I really would like to know because I am new to climate science. But for the record, testability is not a fine point no one but trained individuals should care about. It is the core of the scientific method. It also applies to legal matters. Would you rather be tried on untestable assumption or verifiable facts? Or at least testable hypotheses?

    Comment by ocean — 23 Apr 2006 @ 1:27 PM

  90. Re raypierre response to my remark #69:

    Yep, I see, “less than honest about”, “simply making unfounded assertions”, “had any credibility in criticizing climate science” … Nice lineup of solid scientific arguments. Why not to drop this BS and stop embarassing yourself?

    Let’s take the paper. You state that the paper “is a model of clear statement of assumptions, procedures and objects”. I sort of disagree, quite a few assumptions are not spelled out. For example, the paper states that their model usues “the usual horizontal grid of 3.758 longitude 2.58 latitude and 19 layers in the vertical.” For an unsophisticated reader it sounds like a great deal, while we all (all?) know that subgrid models do not resolve actual weather patterns, therefore some parametrisation has to be involved, with all necessary assumptions/simplifications, implicit or explicit adjustment of fluxes, etc. As result, the assessed value of model’s predictive power must be considered mostly as a matter of computational curiousity, with some resemblance to historical data being by design and as a result of subjective trajectory discrimination. I certainly do not mean that this kind of statement should be included in the paper itself, but when it comes down to unscrupulous interpretation of the paper results in press, some reputable (and honest) scientist must stand up and spell it for unsuspecting public.

    Regarding the “gobbledegook alchemical claims” of Dr. Jaworoswki, maybe you can clear my confusion and present quantitative analysis of changes in gas composition that occur during 2-3 millenia of air occlusion time, pressurised stage for 400,000 years, and drillng and sample extraction phases? With error bounds for each step please.

    Also, could you be more specific on which part of my post do you consider as “multisyllabic gobbledegook”, other than declaring this monosyllabically?


    P.S. When you delete some posts from the pipeline, could you please reallign reference numbers as well. Or maybe it would be easier just to delete the content as, say, “unrelated garbage deleted for clarity and space saving”, but leave the number intact?

    Comment by Alexi Tekhasski — 23 Apr 2006 @ 2:02 PM

  91. #68 Steve, your absolutely correct, we especially have to publish findings without necessarily understanding everything.

    [Response: Yes, consider the progression in climate science. Based on work of Herschel, Fourier concluded that the effect of atmospheres on infrared had a warming effect. He published that even though he had no understanding of what gases in the atmosphere trapped infrared, or even how infrared emission depended on temperature (save that it went up with temperature). This stimulated Tyndall to start doing spectroscopy. Meanwhile Stefan and Boltzmann discovered the sigma-T**4 law, and then Arrhenius put it together into the first predictions of warming. Arrhenius himself didn’t understand how the oceans affected CO2, and for that reason could not quantitatively estimate how much CO2 would rise. That was left to Revelle and Suess, a half century later. Publishing incomplete theories with major gaps is part and parcel of the dialog that allows science to progress. –raypierre]

    Comment by wayne davidson — 23 Apr 2006 @ 2:22 PM

  92. Raypierre,

    Your response to Wayne Davidson [I think post 92] is very interesting. Is there a book you can recommend for the history of climate science or let’s say global warming science? I love to give my students many examples of the scientific method in action. I would much appreciate any reading suggestions you have.

    Comment by ocean — 23 Apr 2006 @ 2:56 PM

  93. Possibly this one:

    I’ve yet to get into it but the chronolgy looks valuable.

    Comment by Mark A. York — 23 Apr 2006 @ 3:11 PM

  94. re 62. [I hope I find out through RC discussion what climate scientists think of Revkin’s article overall.]

    Yelling ‘Fire’ on a Hot Planet, New York Times,
    April 23, 2006 by ANDREW C. REVKIN

    Excerpts: … The latest estimates, including a study published last week in the journal Nature, foresee a probable warming of somewhere around 5 degrees should the concentration of carbon dioxide reach twice the 280-parts-per-million figure …

    A Gallup survey last month shows that people are still not worried
    about climate change. When participants were asked to rank 10
    environmental problems, global warming was near the bottom,…

    … according to “Americans and Climate Change,” a new book by the Yale School of Forestry and Environmental Studies. … “Urgency is especially prone to being discounted as unreasoned alarmism or even passion.”

    Earlier, in comment 52, Coby wrote: … The real challenge that science faces here, is getting across the message that 3C is hugely problematic! …

    I agree. Lindzen and company belittled the last 100 years of global temperature increase of around 1 degree as being inconsequential. However, even just 1 degree warming was huge in high latitude areas where polar amplification is occurring (early Jan 2006 post at RC).

    What may be helpful is a scale similar to those used for hurricanes, tornadoes and earthquakes. Projected changes as a result of 1, 2, 3 … 5 degrees C global warming per 100 years might help people get a feel for what’s coming.

    Comment by pat neuman — 23 Apr 2006 @ 3:18 PM

  95. I hope readers will re-read JohnLoPresti’s comments and think about his list of consequences. There might be none of the cinematic disasters associated with AGW and huge numbers of people could suffer terribly. Agriculture depends upon regularity and predictability. The optimum conditions for agriculture are that the growing season match what you anticipated when you planted. If it’s wetter, warmer, cooler, drier, windier than what you anticipated that will have an effect on what you harvest. Warmer weather might expand the range on pests or disease. Warmer weather might kill off a beneficial species in your area. Who knows? Agriculture thrives on reliability, and more energy in our atmosphere means more variable weather. A threat needn’t be dramatic or picturesque to be real. Consistently sub-optimum harvests when we depend upon greater and greater bounty is as real a threat as a bullet.

    Comment by Jeffrey Davis — 23 Apr 2006 @ 4:28 PM

  96. re:89. You continue to lump (multiple) assumptions and science together. For the second or third time, science is built upon hypotheses. Read any peer-reviewed scientific journal and its paper to see what we mean. It is the scientific method.

    Comment by Dan — 23 Apr 2006 @ 5:58 PM

  97. Re #34 (comment)

    Raypierre, may I disagree with your downplaying of the role of the sun on climate in the 20th century? Based on a study of Stott ea. (2003), The Hadcm3 model probably underestimates the influence of solar variations on climate with a factor 2. And the “best estimate” was that solar was responsible for 40-60% of the warming in the first halve of the 20th century, but still for 16-36% of the second halve, depending on the solar reconstruction that was used and within the constraints of the model. Not directly a small effect.

    [Response: I already corrected your misreading of the Stott et al study once, and I’m not going to do it again. I have also edited out your repetition of the discussion of the supposed sun-cloud correlation in Johanssen et al. which is also well-trodden material not worth repeating. Let’s not go round and round the same circles. It wastes everybody’s time–raypierre]

    Btw, I had consecutive a few models running in background on my computer, until a hard disk crash, just before I heard about the “11 degrees C” news in the media. At that moment I felt quite disappointed by the hype about the more extreme results of the experiment. The explanation by Myles Allen make me think to work again with the project. Will see if I do that or play with a model where I can do runs with my own parameterizations and efficacies (like 3 times solar!), after the climate models course I will follow in Oxford…

    Comment by Ferdinand Engelbeen — 23 Apr 2006 @ 6:44 PM

  98. Thanks Mark. That’s a cool website!

    Comment by ocean — 23 Apr 2006 @ 7:07 PM

  99. RE #61: I understand scientific method perfectly well, being a scientist myself. I have read the paper in question, and because of the serious methodological problems with it (but nevertheless it got into Nature – go figure), it is considerably less alarming than the press release issued by the researchers themselves.

    So how can you draw any other conclusion than the one I made? If I am so off the mark, what was the point of the press release?

    To raypierre: I have never heard of this “Graeme Bird” character. Instead of deleting posts that are contrary to your point of view, why don’t you address the issues raised?

    [Response: Anybody reading the comments can see that I do not delete posts just on the grounds that I disagree with them. I have been attempting to keep out posts that appear to be trolls designed to derail a reasoned discussion without adding anything substantive. We’ve had a certain amount of trouble from a few repetitive posters in that category and your userid and the nature of your post led me to think (evidently erroneously) that you were one of them. Moderation is done in haste, and mistakes do get made. If serious issues are raised, rather than just flat assertions, they do get addressed. So please do tell us just what these serious methodological flaws are supposed to be. –raypierre]

    Comment by Skeptick — 23 Apr 2006 @ 7:16 PM

  100. Re. #93 (as things stand at present :) )


    I’m sure Raypierre and others may have other suggestions, but I personally found “The Discovery of Global Warming”, by Spencer Weart, a thoroughly good read when I first got interested in the subject. It details the history of Climate Science, but it doesn’t restrict itself to pure science – it also looks at how the public has responded to reports in the press, how the Government has reacted, and includes models of climate change.
    Best of all, Spencer Weart has produced an on-line version of it at The American Institute of Physics.

    So your students wouldn’t have to pay for a hard copy (unless they really want to, of course!).

    Comment by Stewart Argo — 23 Apr 2006 @ 7:52 PM

  101. Thanks Stewart Argo!!

    Comment by ocean — 23 Apr 2006 @ 7:55 PM

  102. Re. 99:

    I see Mark beat me to it. :)
    Still a good read, though.

    Comment by Stewart Argo — 23 Apr 2006 @ 7:56 PM

  103. Re: Raypierre’s response to comment #32—

    As nice as your statement sounds (about any relatively educated layperson being able to understand and critically evaluate the basic arguments regarding AGW), I do have my doubts about this. I think that some people have taken the notion of “democracy” a little too far. Sure, everybody has a right to their own opinion, but I think that a democracy does not mean that you should not at least put more respect in the opinions of experts…After all, everyone can’t be an expert on everything. And, quite frankly, especially before RealClimate came along, I think the denialists were generally “winning” on the web as they had arguments that often were more convincing to the average person.

    For example, I think the “paper” accompanying the Oregon Petition is quite convincing if you don’t have the sufficient knowledge and background to see through it. And, the biggest problem I saw was that many climate scientists seemed to believe that things like the IPCC report and the NAS report could somehow counter the messages being put out by things like the Oregon petition. Unfortunately, I don’t think it works to just tell people the correct science…You also have to explicitly explain to them why the incorrect arguments propagated by the denialists are incorrect. Again, I applaud RC for finally filling this void. [Another way to look at this is to note that a dry report, like what the IPCC and NAS put out, that critically evaluates the science will lose almost everytime in a “debate” against something put out by the denialists with the expressed intent of convincing people of a certain point of view by cherry-picking the evidence and so forth.]

    When I talk to people about climate change (and the one time that I gave a talk on climate change at a physics colloquium), I always like to emphasize the fact that I am a PhD physicist who has spent considerable time reading up on the issue, including many of the actual papers in the peer-reviewed journals, but even with that background I still am not arrogant enough to believe that this qualifies me to have a truly independent opinion on the subject. (And, thus, I explain, what I will present to them is basically what the consensus opinion is in the field as I, as an outsider, understand it.)

    So, to sum up, I think democracy works best when those involved do have enough humility to put at least some trust in experts. Of course, as much as possible, I think it is good for these people to educate themselves on the subject…but they should do so with great humility…i.e., with the idea that they are still going to be at a considerable disadvantage in understanding to those who are trained and working in the field. Or, as I like to tell people, even if I read up quite a bit on flying airplanes, I would still not be silly enough to believe when I step on a 747 that I have just as good an opinion about how to fly the plane as the pilot does.

    Comment by Joel Shore — 23 Apr 2006 @ 8:25 PM

  104. Wow, I applaud your post Joel Shore. I have posted several messages earlier about how the general public is under-educated in science [and often this is not their fault]. If people were offered a better education in science [any science] in high school, I think they would be able to respect expert opinion more. This is like anyone watching a ballet performance thinking they are qualified to judge the skill of the dancers. Each person may form an opinion of how enjoyable the performance was, but only a professional ballet dancer is qualified to judge the merits of the performance. To think otherwise is simply ignorant arrogance.

    Comment by ocean — 23 Apr 2006 @ 8:34 PM

  105. RE #100[Response by raypierre]:

    As the OP originally stated:

    …we were quite critical of their basic conclusion – that climate sensitivities significantly higher than the standard range (1.5 – 4.5ºC) were plausible – because there is significant other data, predominantly from paleo-climate, that pretty much rule those high numbers out…

    However, this points not so much to “methodological” problems with the paper (a poor choice of words on my part), but to an outstanding issue with GCM models in general. I think what are doing is in fact exactly what needs to be done to understand the extent to which GCM models are too heavily parameterized to generate reliable predictions.

    The correct interpretation of their results is not that climate sensistivities are significantly higher than “the standard range”, but that under plausible parameter variations, the models exhibit implausible sensistivities. That points to fundamental problems with the model, not necessarily fundamental problems with the climate.

    I am a skeptic precisely because a lot of what passes for climate science is in fact “climate model science”, and the models are nowhere near well-enough understood yet to equate the two.

    Comment by Skeptick — 23 Apr 2006 @ 8:34 PM

  106. Alexi,

    On the subject of disclosing and defending assumptions, you should make it more explicit that underlying all of your arguments about climate behaviour and prediction is the assumption that climate is chaotic, I have even seen you defend the statement that climate is chaotic on all timescales.

    I may have asked you this before, but woud like to know on what evidence do you base this assumption? While the climate may be chaotic on some timescales (ie millions of years at one end and very short timescales where it interfaces with weather) it seems to me that all evidence thus far indicates that climate is broadly deterministic in its response to forcings, at least on any timescale that concerns policy decisions.

    Why are you so convinced it is chaotic and fundamentally unpredictable?

    Comment by Coby — 23 Apr 2006 @ 9:57 PM

  107. I remember that before the ozone depletion science was proved, that the science (models and understanding) underestimated the CFC and HFC damage potential to the ozone layer. Science can indeed lean to the conservative side.

    I hope the GW science is not also being too conservative. There’e lots we still don’t understand about GW positive feedbacks…such as when glaciers suddenly started collapsing when a critical part of it disappeared, or of all the mechanisms for polar ice melt which accelerated polar ice melt beyond many predictions.

    Comment by Richard Ordway — 23 Apr 2006 @ 11:56 PM

  108. RE #112: I don’t understand. What does fuzzy logic have to do with it?

    If a model is over-parameterized with respect to the available data, you can’t be confident of its out-of-data predictions. That’s basic statistics – it’s called overfitting.

    One way to (empirically) determine whether a model is over-parameterized is to vary its parameters within reasonable physical boundaries, and look at whether the predictions continue to be reasonable. That’s pretty much what the folks did, only instead of interpreting their results as casting doubt on the models’ predictive capabilites, they interpreted their results as cause for greater alarm about global warming.

    Comment by Skeptick — 24 Apr 2006 @ 12:49 AM

  109. Re #108: Coby, “on what evidence do you base this assumption [climate being chaotic]”? and “it seems to me that all evidence thus far indicates that climate is broadly deterministic in its response to forcings”.

    I am not sure which evidence do you have in mind. For example, this very relevant framework (and the subject of this thread BTW) obviously deviates from your line of evidence:

    It is useful to try to approach the problem from the opposite end. Every motion that involves more than three molecules is chaotic, and only a few extremely purified problems can be approximately treated as non-chaotic for certain narrow practical uses. Given obviously irregular character of all historical data regarding climate, it is a tough sell to start with an assumption that everything is in a global equilibrium, and only spontaneous external events like eruptions or large meteors are the cause of that variability.

    People here are trying to artificially separate short-term “internal variability” (weather and maybe some seasonal trends) from effects of “external forcing”. The problem here is that the “forcings” are in fact some other inherent variables of the very same climate-bearing system, but there is no clear separation of time scales that allow for any sort of coherent theories like “averaging of fast motion” that results in Landau-Ginzburg-type equations for “slow envelopes”. This is the same ugly face of the general problem of turbulence – continuous spectrum of scales, so any artificial limit on the length of averages will always miss something, and the simplfied equations cannot form a closed solvable set (someone here was confused about importance and relevance of this problem).

    However, no matter how paradoxical it may sound, there is no contradiction between globally-chaotic behavior of climate variables, and “broadly deterministic response” to “forcing”. While the underlying climate variables are obviously fluctuating chaotically within their own ranges and time scales, it is true that at almost any given time the system would react almost deterministically to perturbations, it is a well known fact that geodesic flow on any dynamical system is simple when current state is far from a degenerate point, one can define and calculate Lyapunov exponents along the flow etc. The problem is that the values of Lyapunov exponents usually vary along the attractor (so the direction of “response” may change), but you don’t know where you actually are on the global cycle of nature. Without knowing the bigger picture (i.e having right global model of glaciations-deglaciations), the “local’ responses may be misleading, especially for practical purposes.

    For example, if you examine the ice core data, say from Vostok station
    you may find many episodes with “bizzare” behavior. For example, for a whole period of 3000 years, between 234ky BC and 231ky BC, CO2 was generally rising while temperatures were dropping steadily. For another thousand years from 224ky BC to 223ky, the trend was opposite – T was on the rize, while CO2 was going down. From 215ky to 212, for another 3000 years, again the CO2 was up while T was going down. I am sure one can find many more episodes of this sort. The irony is that that were outputs from the same system, that’s why I question completeness of most current models.

    It is interesting that Gavin has stated on one of your blog thread,

    “Let me state my essential point more clearly – in NO model of the atmosphere that passes basic screening for a reasonable climate and is in equilibirum with the atmospheric composition and sea surface temperature will the sensitivity to 2xCO2 be negative.”

    So, it looks like the observaions I mentioned above prove that something is wrong in the process of model construction, some basic assumption. I wonder, which one?

    (I’m afraid the above might look as another “multisyllabic gobbledegook” for some, so I will stop right here;-)

    [Response: Almost all of these issues have already been thrashed out in the article Chaos and Climate In short, there is no real evidence that climate is chaotic in the usual sense. One cannot infer chaos by just an irregular or “bizarre” appearance of a time series. It is not, in principle, impossible for coupled ocean-atmosphere climate to be chaotic, but all evidence so far points to the likelihood that the strength of the response to GHG radiative forcing changes overwhelms the effect of any chaos there may be in the system. The observations you mention do not by any means prove something is wrong in the process of model construction. You have taken Gavin’s statement out of context, and have completely failed to appreciate that other climate factors need to be taken into account in interpreting the Pleistocene record. Orbital parameters are changing, as is atmospheric dust, and glaciers have a dynamics of their own which can lead to short-term decorrelations of temperature and CO2 over periods of a few thousand years. The CO2 radiative forcing changes over the time periods you cite are far smaller than what would be caused by a doubling of CO2. –raypierre]

    Comment by Alexi Tekhasski — 24 Apr 2006 @ 12:57 AM

  110. Getting back to the issue of “How not to write a press release” readers may well be interested in’s take on that particular press release In difference to the “alarmist” 11 degrees C interpretation they are suggesting that the model is flawed. Its worth getting past their tabloid like headline “Climate change: a model cock-up” to where they do try to address the issues regarding climate modelling.

    Comment by JAC — 24 Apr 2006 @ 1:20 AM

  111. Re response to #115 by raypierre:

    I see some continuing misunderstanding of the subject, or what I tried to say. But first, nothing so far has been “thrashed” or “debunked” in that article, starting form completely false statement (and non-sequitur argument) like:

    “Chaos is defined with respect to infinitesimal perturbations and infinite integration times, but our uncertainties in the current atmospheric state are far too large to be treated as infinitesimal”

    Or this false construction:
    “Although ultimately chaos will kill a weather forecast, this does not necessarily prevent long-term prediction of the climate. By climate, we mean the statistics of weather, averaged over suitable time and perhaps space scales”
    As I said, since the original attractor is chaotic, there is no “suitable” time nor space scales, just remember the problem of turbulence.

    Or this misappropriate statement:
    “We cannot hope to accurately predict the temperature in Swindon at 9am on the 23rd July 2050, but we can be highly confident that the average temperature in the UK in that year will be substantially higher in July than in January.”
    Dare to predict whether the 2050 summer season will be dry or rainy in that area, to plan accordingly for agricultural activities?

    Or this example of illogic:
    “Imagine a pot of boiling water. A weather forecast is like the attempt to predict where the next bubble is going to rise (physically this is an initial value problem). A climate statement would be that the average temperature of the boiling water is 100ºC at normal pressure”
    What if your pot has a lid that has certain weight and might melt down over the time? How accurate now is your statement?

    About examples of Lorenz attractor. Why do you assume such a limited case of one? Why don’t you consider that you might have a dozen of Lorenz-type attractors, all operating on a certain spectrum of time and space scales, and intertwined to different degrees via their coefficients and “forcing” terms? Say, some internal variable (like ice mass) would modulate the “r” parameter of your main Lorenz attractor on a time scale of 100 years? Dare to predict your 30-years average now?

    And what the heck is this, “the directly policy-relevant portion is on the multi-decadal and centennial time scale”? Are you doing a science here, or trying to fit it to the purpose of politics? Why don’t you simply say, hell with all this multisyllabic gobbledegook about chaotic-non-chaotic, we need to act now no matter what the freaking science might be questioning?

    In short, the article
    completely failed its purpose.

    About “forcings”. As I said, all your forcings (and glaciers and dusts) are in fact another variables of the same coupled climate system, and their scales are not separable so you can’t consider them as independent variables. Yet you say that I failed to appreciate other climate factors. How do you “appreciate” these factors yourself when building your current models? How do you know that we are not near that “short term de-correlation” period of some-1000 years long? And which one of the two “de-correlations”? How do you know that the amplitudes of “CO2 radiative forcing changes” were “far smaller” 200,000 years ago while all data are effectively smoothened over 3000-5000 years by specifics of gas occlusion process?

    [Response: You’ll find that as a technique of getting answers (assuming that’s the goal), keeping to one topic at a time is more useful. In this post you confuse a number of issues to nobody’s benefit. To take just one – the relevance of the boiling water example. The question you ask is what is the dependence of the boiling temperature as a function of pressure – this is a climate question that can be addressed very simply without considering the details of the turbulent flow. What we are talking about in climate is are small changes in the attractor as a function of different forcings, and we have gone over this before. Simply switching venues and starting over is no way to have a conversation. – gavin]

    Comment by Alexi Tekhasski — 24 Apr 2006 @ 3:37 AM

  112. i find your article and the responses you received very interesting. the real problem here (well the one that you stated) is media coming in the way of science and forming a statement that the masses rely on as the “truth”. every one who has seen scientific briefs know that there is some area within the study that is left unexplored (if everything were explored nothing would be a mystery). just look at that micheal crichton book, i heard that NBC called him up to have him explain his “theory”. what theory? the guy is a fictional writer, for crying out loud…

    Comment by reden — 24 Apr 2006 @ 4:20 AM

  113. Apologies all round for some of the confusion in this thread with regard to who is posting. I would like to make this crystal clear. Any comment that is posted where someone pretends to be one of the other posters, will be deleted immediately and the poster permanently blocked.

    Comment by Gavin — 24 Apr 2006 @ 9:17 AM

  114. The busy lay reader generally just wants to know where current scientific thinking is regarding the question: “how hot might the earth get and what is the chance of this occurring?”

    If I have it right, the discussion in this thread is about climate sensitivity to CO2 levels and the predicted temperature increases mostly being disputed here do not include any consideration of the possibility of increasing temperature causing increased release of CO2 or methane from natural carbon sinks.

    If this is the case, all this discussion about climate sensitivity, while centrally important from the point of view of getting the science right for modelling, is not the immediate key real world question the lay reader wants answered.

    The way I read the discussion here (sorry I have not read the original papers being discussed) is that the new work which showed a lower range of temperatures (Hegerl study noted in #2) shows a 5 percent chance of the temperature going over 11 degrees F. That probability needs to be increased by whatever probability estimates climate science can provide of temperatures up to 11 degrees initiating reversals of natural carbon sinks and racking up CO2 equivalent levels further. That then gives a better estimate of the actual real world estimated probability of temperatures going over 11 degrees F. This figure is of more relevance to risk management than raw climate sensitivity estimates (essential though they are for doing the calculations).

    Are there estimated probabilities for the initiation of carbon sink reversals for temperatures up to 11 degrees F and how would you best factor them into the probability estimate for going over 11 degrees F.

    Comment by Paul Duignan — 24 Apr 2006 @ 10:15 AM

  115. Re: #111

    I agree with one of the ideas that you’ve expressed in previous posts, namely, that we can’t be certain that model parameters or model behavior correctly reflect the actual dynamics, so we have to take model simulation results with a grain of salt. But, your recent posts suggest that you don’t just want to put a grain of salt on it, you want to bury it in a mountain of NaCl.

    You remind me of Churchill’s definition of a fanatic: someone who can’t change his mind, and won’t change the subject.

    Some of your objections are utter nonsense. Like this one:

    Or this misappropriate statement:
    “We cannot hope to accurately predict the temperature in Swindon at 9am on the 23rd July 2050, but we can be highly confident that the average temperature in the UK in that year will be substantially higher in July than in January.”
    Dare to predict whether the 2050 summer season will be dry or rainy in that area, to plan accordingly for agricultural activities?

    Nobody pretended to be able to predict whether summer 2050 will be dry or rainy. The claim was high confidence that summer in the UK will be hotter than winter. You said nothing about that. And the example makes an excellent point, that even chaotic systems can show predictability, especially when they’re subject to forcing or constrained by conservation laws. You said nothing about that, either.

    Or this example of illogic:
    “Imagine a pot of boiling water. A weather forecast is like the attempt to predict where the next bubble is going to rise (physically this is an initial value problem). A climate statement would be that the average temperature of the boiling water is 100ºC at normal pressure”
    What if your pot has a lid that has certain weight and might melt down over the time? How accurate now is your statement?

    This is ridiculous (by which I mean, worthy of ridicule). I might as well say, “What if your pot is made of green cheese? How accurate now is your statement?”

    What’s next? Will you invoke the Heisenberg uncertainty priciple to claim that no computer simulation will ever truly reflect actual climate dynamics?

    Comment by Grant — 24 Apr 2006 @ 10:44 AM

  116. Re #114 – what you speak of is known as positive feedback and yes I would imagine that most climate models are models of CO2 sensitivity due to CO2 levels rising due to human output and known natural means only and not by additional events such as the permaforst melting, or rain forests drying out of which both would potentially add large amounts of additional CO2 into the atmosphere.

    Maybe real climate can clear this one up for us all. Do climate models predict anything other than human CO2 release ?

    [Response: Some climate models include full carbon cycle models – these predict CO2 in the atmosphere as a function of human emissions, and feedbacks in the carbon system (uptake by plants, ocean, releases from soils etc.). These generally show a postive feedback on CO2 levels in a warming climate, though the magnitude of the effect is rather uncertain. However, when we talk about climate sensitivity or about the models in the IPCC AR4 comparison, these have CO2 levels and their future trajectory prescribed according to different sceanrios. – gavin]

    Comment by pete best — 24 Apr 2006 @ 11:29 AM

  117. Here’s a good press release (from the food/safety area)

    Comment by Hank Roberts — 24 Apr 2006 @ 12:09 PM

  118. #re 116

    And those alternatives from the IPCC show us that the worse case scanario is around 11 F of warming?

    Comment by pete best — 24 Apr 2006 @ 12:19 PM

  119. I have a question that may be considered irrelevant, and I apologize in advance if it is. Just ignore it please in that case. A couple of my students made a “greenhouse” in the form of a glass box. We saw a significant temp increase when we left it under the sun for a few hours. Then overnight, we put some dry ice in the box and sealed it with masking tape on all edges. Left it over night so the dry ice would sublimate and the gases in the box would reach room temp. The next day, we put it under the sun for the same amount of time as the day before. But we didn’t get any more temp increase in the box than the day before. So what did I do wrong with the experiment? I mean shouldn’t the CO2 in the box have “trapped” more heat? I thought this would be a relatively cheap and easy way to demonstrate the greenhouse effect to a bunch of freshmen, but clearly I am wrong. Please help with any suggestions.. Thanks in advance.

    [Response: It’s not exactly on the topic of this thread, but there ought to be some place where people can ask such questions. It’s perfectly reasonable. The answer is that the greenhouse effect needs more than just absorption by CO2. It also relies on the radiating temperature being different from the surface temperature, which generally requires a temperature decrease with height. You get that in the atmosphere from compressibility effects, but you don’t get that in your box. For some introductory material on how the greenhouse effect really works, take a look at my post A busy week for water vapor, or at Chapter 3 of my ever-evolving Climate Book. Dave Archer’s global warming book, linked through his web site at U. of Chicago, has a more elementary explanation of the same things. Actually, as a model of the greenhouse effect, the box experiment has a lot wrong with it. It’s actually dominated by the effect of the lid on turbulent heat transfer out of the box, not on the infrared blocking properties of the glass. Many people blame Fourier for the faults of this experiment, but it isn’t generally recognized that the experiment was actually designed by Horace de Saussure, who used it as a means of measuring the intensity of solar radiation on mountains. Fourier used it only as a loose analogy for the principle of energy balance, and stated clearly in his treatise that he knew the shortcomings of the experiment as a model of the greenhouse effect. Some of the historical perspective concerning Fourier’s work can be found in my Fourier essay on my web site ( , then follow links to publications), my annotated translation of Fourier’s treatise, and in William Connolloys excellent online translation cited in the latter. Probably at some point I’ll do a post on Fourier and the box experiment, but right now more pressing duties call –raypierre]

    Comment by ocean — 24 Apr 2006 @ 1:19 PM

  120. What grade level and school system are you teaching in?
    I have friends and inlaws teaching first and fifth (US) elementary grades who have teaching material available.
    You’ll need to understand some basics, where do you get help as a teacher? Do you mind my asking your credential?

    Comment by Hank Roberts — 24 Apr 2006 @ 1:34 PM

  121. Ok I think I can answer this. Even according to the conventional (wrong) story about how greenhouses work, this would not have been successful. According to that story visible light passes the glass some gets converted to longer wave length light and thus when it trys to exit the greenhouse through the class bounces off. More CO2 and less oxygen or nitrogen would have no easily affect in this scenario. (You need a lot of co2, the amount in an atmosphere to have a similar affect.)

    However, when it comes to greenhouses, this explaination of the greenhouse affect is wrong anyway. Many greenhouses are made of plastic which let the long wave lengths in the light spectrum through in any case. What happens in a greenhouse is unlike the larger atmosphere you have traped the air. Hot air rises and is replaced by colder air outside of a greenhouse. Inside a greenhouse, hot air can rise only so far; so the cold layer of air on the bottom can get heated too. Also I suspect that there is less air movement (convection) within a greenhouse than outside, so air in a greenhouse is an insulatior (albeit a poor one). That is what produces the greenhouse affect in greenhouses. The greenhouse affect does work in the atmosphere beacause thousand of meters worth of greenhouse gases do reflect the really long waves back.

    OK that is amateur’s attempt to explain. The real scientists can correct anything I have wrong.

    Comment by Gar Lipow — 24 Apr 2006 @ 1:40 PM

  122. Regarding land resposes to co2 emissions This study on maximum limits of land storage for atmosperic co2 claims that at best the land biosphere will remove about 30% the co2 emissions over 50 years.

    To illustrate the uncertainty, the same authors claim, “..40% of total anthropogenic emissions have remained in the atmosphere. The remaining 60% was absorbed by the oceans and the land biosphere”

    Computing the land bioshpere equilibrium point is a hard problem. The greatest uncertainty is in how we react to the opening up of greater northern hemispherical land mass to longer seasons, the rate at which we abandon older cropland for more intensive agriculture, and the manner in which we introduce plant species, especially in forestry.

    Comment by Matt — 24 Apr 2006 @ 1:56 PM

  123. Re #115:
    Yes, you have mis-interpreted my prior statements about model parameters as being only inaccurate. Now you get it correct: I claim that the linear response models (“sensitivity studies”) are fundamentally insufficient for the purpose of prediction and “policy making”. As an example, when a direct long-term simulation of weather (sort of) is conducted (as in ClimatePerdiction.Net framework, see #67 above), the model shows all sort of behaviors, including measurable number of scenaria when adding CO2 results in _cooling_, which contradicts “more CO2 == always more T” for time horizons longer than 5-10 years. Another historical records of 1000-years-long “de-correlations” are given in #109. Modelling the sensitivity to a parameter is grossly insuffucient when you failed to consider the self-contained dynamics of the parameter itself. You want to measure sensitivity? Fine, but don’t claim a doom please.

    About the 2050 summer in Swindon. The original claim was absurd, there is no new information in the statement that summer will be hotter than winter. This is a trivial statement that holds no predictive power. The whole topic is and always was about climate prediction, and specifically for practical purposes and “policy making”. I just tried to demostrate that the climate (even as it is defined) is no more predictable than weather when it comes down to practical purposes. However, I have to make my statement more adequate, it should say: “Dare to predict whether the 2040-2060 summer seasons in the area will be more dry or more rainy than today?”

    About the pot with boiling water. You miss the whole point. It does not matter what the pot is made off, green cheese or chicken poop, but it does fundamentally matter if the lid is included in the model or not. Since our real system does have a sort of lid (which builds or releases excess of “pressure”, flipping quasi-randomly), the statement that “average boiling temperature is 100C, and we perfectly know how it depends on pressure” does not have any predictive power since you deliberately excluded ways/models to predict what the actual pressure might be. Therefore the original example about how easy the climate can be predicted is plain incorrect and grossly misleading for “policy makers”, which is not a laughing matter at all.

    What is next? I will try to exclude “multisyllabic gobbledegooks” as “uncertainty priciple”, “differentiable manifolds” and “Anosov diffeomorphisms”, and use simple understandable terms like “green cheese”, “pot lid”, and “crackpot”, if you prefer :-)

    [Response:What is next is that I’m not going to bother responding to any more of your posts, because you have shown yourself incapable of or unwilling to learn from what you have read. I’m not impressed by your name-dropping either. Plenty of us here know all about differentiable manifolds and diffeomorphisms, and are not particularly impressed that you know how to spell these words. –raypierre]

    Comment by Alexi Tekhasski — 24 Apr 2006 @ 2:50 PM

  124. Re #119: Alexi, I previously posted, on a previous thread I think, regarding my view that we are all ‘gentlehommes’ until proven otherwise. Your first three paragraphs were mostly ok, making good points. Your last paragraph strikes me as an attempt to be insulting, and beyond my understanding of ‘gentlehommes’. Moderate it or I’ll call for a vote.

    In the meantime, if you can do a bit better job to sticking to one point at a time, avoiding anything that can possibly be considered insulting, I want to read what you have to say. Sometimes it is actually valuable. Thank you.

    Comment by David B. Benson — 24 Apr 2006 @ 2:58 PM

  125. Yes, I would also appreciate dropping the hostile back and forth among posters and, instead discussing and criticizing ideas. Eleanor Roosevelt said: simple minds talk about people, average minds talk about events, great minds talk about ideas. I am trying to learn about global warming science and value everyone’s opinion, but the hostile static has got to go.

    Comment by ocean — 24 Apr 2006 @ 3:02 PM

  126. I should also clarify the specifics of our experiment [Thanks Gar Lipow for your response and maybe specifics would be more helpful]. Our glass box is 2 feet by one foot by one foot. We used about 1.5 pounds of dry ice. And Gar, you are right we should have used plastic and maybe that would be a good change to make for next time. But we weren’t trying to make a greenhouse. We were trying to see the potency of CO2 as a greenhouse gas in trapping heat. Just some details, and I really appreciate any input I can get. Thanks again.

    Comment by ocean — 24 Apr 2006 @ 3:10 PM

  127. “but the hostile static has got to go.” that’s great. But what about the relentless censorship. Could you put your attitude toward ending that also?

    [Response:At the risk of again derailing the topic, you are wrong about this. If people make serious points in constructive ways, it gets through and is responded to. Meaningless attempts at point scoring, repetition of already discussed items, personalisation of scientific topics, trolling for effects etc. do not. It really is quite simple. – gavin]

    Comment by Dan — 24 Apr 2006 @ 3:17 PM

  128. Ocean, do you have access to public school teaching materials? I know first and fifth grade teachers who have materials for this sort of study.

    Seems to me you need some very basic physics first. Heat transmission is not the same as heat storage. When you fill an aquarium with CO2 you make it transmit less of a certain range of infrared wavelengths. If you can get an infrared camera, or infrared film and filter, suited to taking a picture at those wavelengths, you can demonstrate how an aquarium full of ordinary air transmits infrared light vs. the same aquarium full of carbon dioxide.

    But that’s going to require understanding the wave theory of light, atomic/molecular absorbtion and so on.

    You seem to be thinking that CO2 somehow “traps” or “holds onto” heat as though a tank full could be used to store it, and that an aquarium full of CO2 sitting in the sunlight is going to store up more heat than an aquarium full of air? That’s “specific heat” — explained here:

    I can’t comment on whether the specific heat has anything to do with the ability to block infrared wavelengths transmitted in the atmosphere. Anyone?

    One aside that might be helpful — the amount of CO2 in the atmosphere is in parts per million. Seems like not much. I found this analogy somewhere: ordinary window glass is something around 91 percent transparent, passes that much visible light. A thin sheet looked through seems clear. The same sheet looked through along a long dimension, ‘edge on’, will look very greenish.

    Comment by Hank Roberts — 24 Apr 2006 @ 3:40 PM

  129. Re #120:
    David, I am curious where have you been when I was accused of dazzling the thread with “multisyllabic gobbledegook” (#68), and the accusation was even supported by the host, raypierre(#69)? I was depicted as “less than honest about”, “simply making unfounded assertions”, “had any credibility in criticizing climate science”. I am just trying to maintain the same friendly level of conversation. Please be consistent.

    Comment by Alexi Tekhasski — 24 Apr 2006 @ 3:46 PM

  130. Re: 122. CO2 in a box that size will not give you a great difference from air. A 2X1X1 box filled 100% with CO2 will not give you significantly more heat than a box that size filled with air. Remember global warming is caused by layers of CO2 25 km’s high – though only a fraction of a percent CO2. To equal that thickness of CO2 you would need pure CO2 33 feet thick. In another words you would need a box 33 feet high. And even that would not do it because much of the greenhouse effect comes from feedbacks. As the atmosphere warms it can hold more water; that additional water vapor provides more of the warming than is directl caused by CO2. In short to get the affect equivalent to the current affect of CO2 you have to fill a 33 foot high box with CO2 and have the floor cover mostly pans of water . Even so this omits gases other than CO2 which are responsible for about half of human cause global warming. Still if current human contributions have created almost a degree of warming to date, that box might create about half a degree of warming compared to a second box filled with air, floor covered with the same pans of water. Of course there are probably other factors that might make the difference less. Given that small difference you would have to have two boxes at the same time, not the same box at diffent times, cause normal variations in temperature from day to day would swamp your results. And you would have to have awfully sensitive thermometers to capture difference of half a degree or less. Also you would have to be careful about placement. I could think of a few other things that could lose these small differences in noise.

    Comment by Gar Lipow — 24 Apr 2006 @ 4:00 PM

  131. I’m not sure about the experiment except to say that in the greenhouses I built in Maine, I installed heat-activated vents on each gable end otherwise the plants would fry depending on sun intensity. Maine’s very cloudy and humid anyway, cold too, but as an aside they are tapping maple trees in February these days.

    Comment by Mark A. York — 24 Apr 2006 @ 4:06 PM

  132. Hi all, and thanks for all the responses I just received all of the sudden :) As far as credentials go, I have a PhD in geology. I am a professor at a university. But I just wanted some simple “heat trapping” experiment to give my students first hand experience. But as I said earlier, I am not a climate scientist and have much to learn [as you can see]. But maybe infrared camera is a way to go? I hadn’t thought about that. Hank, my e-mail is [please don’t laugh] If you have any teaching material they could e-mail me, I would be much appreciative.

    Comment by ocean — 24 Apr 2006 @ 4:15 PM

  133. Thanks Pete and Gavin for your response in #116 that the estimates for future temperature change being discussed in the climate sensitivity studies (discussed in this thread) do not generally take into account the effect of increased temperature on initiating further natural carbon release. I think that the vast majority of lay readers who read the headlines and the text of stories on climate sensitivity do not know this and they simply presume that the scientists concerned are talking about their absolute best estimates of the possible temperature increases which may be faced. Do you think that in the same way that the Solanki et al paper on solar sunspot reconstructions had a specific statement that their results did not contradict ideas of strong greenhouse warming in recent decades, this (the fact that climate sensitivity projections are not best estimates of possible future actual temperature increases) should be clearly noted in media releases put out by scientists when reporting climate sensitivity studies?

    [Response: Yes. That would definitely be useful. – gavin]

    Secondly it seems really important to me for the wider discussion (beyond just the topic of this thread) that some estimate of the “uncertain” potentiating effect of predicted temperature increases be provided and integrated with the climate sensitivity predictions so that we can have a statement that actually attempts to predict possible real world temperature increases. Presumably such temperature predictions are the ones that should form the basis for policy decisions.

    [Response: Indeed. And in fact they do. Climate sensitivity is something that we (as scientists) get excited about because it is a relatively well-posed question (none of that messy economic analysis or human behaviour include). But the projections that end up having ‘policy relevance’ are only loosely dependent on climate sensitivity. They are more directly related to what is called the transient climate response (which takes into account the ocean lags) and the greenhouse gas and aerosol scenarios. These scenarios are the element that needs to include more of the geo-bio-chemical feedbacks that affect CO2, CH4 and aerosols. That is not yet common practice, but it is starting to be done. -gavin]

    Comment by Paul Duignan — 24 Apr 2006 @ 4:28 PM

  134. I’m slightly surprised no-one has mentioned Piani et al. Constraints on climate change from a multi-thousand member ensemble of simulations also from the group. It is in my opinion a more significant paper as it manages to get a PDF out of the results (the Stainforth et al. paper does not attach a probability to any of the outcomes, 11 degrees could not be ruled out, but the [very low] probability attached to such high temperatures could not be estimated).

    The Piani et al. paper gives “the 5th and 95th percentiles are 2.2 K and 6.8 K respectively.” while the “best estimate of climate sensitivity is 3.3 K”. If it is correct it shows three things:

    1. There is almost no chance of a very low climate sensitivity which would enable us to emit CO2 to the limits of available fossil fuels without harmful effects being predominent.

    2. 2 K warming is almost inevitable. Even drastic cuts in CO2 emissions are unlikely to be enough, and there is no sign of even modest cuts happening for the next few years.

    3. There is a significant probability of extremely harmful temperature rises, even the most drastic cuts do not reduce this probability to miniscule levels.

    As interesting as how the media latched on to the 11 K climate sensitivity in Stainforth et al. is their total lack of interest in a much more robust (but equally frightening) result.

    Comment by Mike Atkinson — 24 Apr 2006 @ 4:29 PM

  135. I’ll defer to experts at this point.

    Comment by Hank Roberts — 24 Apr 2006 @ 4:33 PM

  136. Gar Lipow and others,

    I have a question based on your response to my experiment. Please bear with me, my question may sound stupid, but it is a real question to see if I understand what you are saying correctly :) So the percentage of CO2 in the box is not as important as having layers of CO2? Like one wool jacket won’t keep you as warm in winter as layers of flannel or cotton. Is that the right analogy? Because the atmospheric CO2 concentration is like 0.03% and let’s say we have 50% CO2 in my box. But gas pressure would be higher if not the same as atmopsheric pressure in my box. So more CO2 and more pressure, shouldn’t that enhance warming? Like both Mars and Venus have over 96% CO2 in their atmospheres but Mars barely has any atmopsheric pressure, and Venus’ atmophere has 90 times Earth’s atm pressure. So Venus has the runaway greenhouse effect, right? [Disregarding all the other positive and negative feedback mechanisms involved.]

    Comment by ocean — 24 Apr 2006 @ 4:39 PM

  137. “aerosol scenarios”…

    Let’s see…many models show that aerosols could have been artificially keeping the world’s average surface temperature cooler by about 3-5 degrees C from 1900-2000 – (sulfate aerosols certainly have some certifiable cooling effects cancelling out the warming effects of CO2).

    So now get rid of most of the world’s sulfate aerosols in the next 50 years because it’s currently killing people, plants and destroying ecosystems (acid rain, pollution).

    …and all by itself…woops…a possible isolated, independent temperature rise of 3-5 degrees C average world surface temperatures by 2100, not even including any other positive forcings, because the forcing is already there waiting for the cancelling aerosol cooling effect to be removed…

    That is a possible scenario that would certainly push the actual realized temperature increase to the higher end of the “most likely” projected temperature range in a hurry.

    Comment by Richard Ordway — 24 Apr 2006 @ 5:31 PM

  138. 136. No. Basically what we are saying is that normal greenhouse is based on having less thermal mass to heat than the atmosphere as whole due to seperation from that atmosphere, and to a lesser extent on insulation due to the air not moving as much. For a greenhouse a foot or two high, filling it 100% with carbon dioxide won’t make much of difference. Between a two foot high greenhouse filled with atmosphere and a two foot high greenhouse filled with carbon dioxide there would be less than a thirtyieth of a degree difference – provided you had water at the bottom of the greenhouse to provide vapor feedback.

    Multiple layers would make a difference but for still a third reason, having nothing to do with either the greenhouse effect or how human made greenhouse work. Air has insulating value, but because it moves a lot this is overcome by convention. Trap the air in smaller values; it moves less, and some of the insulation value overcomes convection. That is why multi-paned windows have more insulating value than single paned one. (Though there are other things you can do to give windows insulation that give better results for the money.) For that matter, this is how some foams work – trapping air in tiny cells so there is no convection to overcome. (In practice most foams use gases other than the atmosphere; but there a few ‘green’ foams that do in fact use normal air, and they work pretty well.)

    Bottom line, I can’t imagine offhand how you can demonstrate the atmospheric greenhouse affect in a greenhouse two feet high. I’m not saying it can’t be done; I just can’t think of it. Greenhouses work fine but they work on different principles than the atmosphere does.

    Since obviously I was not clear, try this explaination from the Alaska Science Forum.

    The effect from greenhouse gases is a different matter.

    Comment by Gar Lipow — 24 Apr 2006 @ 5:32 PM

  139. Re #119 and posts following (the greenhouse box experiment): I think there was a post here at RealClimate that explained that the forcing effect due to CO2 (or other greenhouse gases) is pretty subtle…even if you ignore feedbacks and all that. As I recall, it turns out that the reason why CO2 produces warming is that it effectively causes the energy emitted back out into space from the earth to be emitted from a higher average height in the atmosphere where the temperature T is colder (since the temperature generally drops with altitude through the troposphere). Since the energy emitted goes like T^4 power, the earth thus emits less energy back into space, which is why it has to warm (until it reaches a temperature when the earth is again emitting as much energy back out into space as it receives from the sun and so is back in equilibrium).

    Clearly, a little box is not going to have a measurable “lapse rate” of temperature from top to bottom like the atmosphere has and thus this effect will not be observed.

    Hopefully, the RC folks will correct me if this is garbled or wrong…but I think this might be the most fundamental problem with your experiment.

    [Response: You are exactly right. The greenhouse effect needs TWO ingredients: a lapse rate which makes temperature aloft colder than temperature at the ground, and infrared opacity of the greenhouse gas, which allows the infrared radiation to escape only from the higher altitude (colder) parts of the atmosphere. –raypierre]

    Comment by Joel Shore — 24 Apr 2006 @ 5:32 PM

  140. Comment 139 was an answer to Ocean.

    Comment by Gar Lipow — 24 Apr 2006 @ 5:33 PM

  141. Thanks Gar Lipow :)

    Comment by ocean — 24 Apr 2006 @ 5:34 PM

  142. Thanks Joel Shore and to all. This has been quite educational for me. And I appreciate it being called “the greenhouse box experiment.” It sounds so sophisticated. I just wish there was a simple demo I could do with my students to illustrate the “greenhouse effect” other than using glass or plastic as analogies…

    [Response: I mentioned some suggestions for additional reading as a comment to your original query up above. There really isn’t any feasible laboratory analogue making use of CO2, but it would be possible to do a reasonable “glass box” analogue which used the infrared absorbing properties of glass — the trick is, you’d have to do the experiment entirely in a vacuum, with the glass box evacuated, but also under a bell jar so that the glass surface couldn’t lose heat from its top by turbulent convection. Interestingly, Fourier says that the experiment ‘would work’ (he uses the subjunctive in the original) in a vacuum, but it sounds like it hadn’t actually been done at the time, and I’m not aware that it’s been done since either. Now, the usual glass box experiment done in air is not entirely pointless either. The essence of the greenhouse effect is that the atmosphere inhibits energy loss (to space) so that for a given rate of solar energy input, the temperature of the surface has to be greater in order to allow the necessary amount of heat to be lost per unit time. Putting a glass layer over a box has a similar effect, except that it inhibits turbulent heat loss rather than infrared heat loss. This is the sense in which Fourier used the analogue in his original paper. One can also illustrate the principal of energy balance with a bucket having a hole in the bottom, put under a running faucet. The input water flow == solar input. The output flow through the hole == infrared loss. The level of water in the bucket == temperature. It’s a very close analogy, also used by Fourier. Apropos of that, Spencer Weart’s book is good, but the only thing I hold against him is that he didn’t seem to understand what Fourier actually did; I don’t think he even read Fourier’s paper. –raypierre]

    Comment by ocean — 24 Apr 2006 @ 5:39 PM

  143. Re #67. Alexi Tekhasski said about the Stainforth article

    ‘I would add that good scientists do not publish results until they understood all caveats, especially instabilities in their models. For example, the Stainforth et al. article states in “data quality” section:

    “Finally, runs that show a drift in Tg greater than 0.02 Kyr21 in the last eight years of the control are judged to be unstable and are also removed from this analysis.”

    Also, from the same source:
    “Most models still maintain a temperature of between 13 and 14 °C, however some get colder – these are not stable and the heat flux calculated in phase 1 was not correct to keep the model in balance.”

    These statements pretty much nullify results of the whole article IMO – it looks like the data were filtered in favor of desireable result – GW.’

    I should point out that in the ClimatePrediction models used, the first two of their three phases were hindcast, control phases using pre-industrial CO2 levels. These phases were included in order to test the stability of each model’s particular set of parameters before increasing CO2 in phase 3. A small number of models showed a slight drop in temperatures, particularly in phase 2. Of course these models had to be excluded from the final study – they did not represent pre-industrial climate accurately! I do not think many (perhaps even any) sets of parameters produced a temperature rise during these control phases. If any had done so, they would have had to be eliminated from the study for the same reason.

    The ensemble of models included in the study therefore consisted of those shown to reliably represent pre-industrial climate. Had this not been the case, criticism regarding the reliability of the ensemble used to show what may happen in the future would indeed have been justified.

    Comment by Maureen Vilar — 24 Apr 2006 @ 4:45 PM

  144. Thanks very much Gavin for response on #133. Regarding #138 do any of the climate scientists (apologies Richard if you also are a climate scientist) want to comment on Richard’s suggested figure of an independent 3-5 degree C rise by 2100 just from a reduction in aerosols.

    Comment by Paul Duignan — 24 Apr 2006 @ 5:51 PM

  145. usually a publication date is announced in a press release, usually the press also receives an embargoed copy upon request so the newspapers can write about the paper that has appeared in the journal


    Comment by Hans Erren — 24 Apr 2006 @ 6:00 PM

  146. Re: 138

    The human generated aerosols that have been selectively eliminated — CFCs — don’t have climate sensitivities anywhere near the order of 3-5C.

    Comment by Jeffrey Davis — 24 Apr 2006 @ 6:50 PM

  147. Re. 138

    “The human generated aerosols that have been selectively eliminated — CFCs”

    Could you please be a little more specific? Do you mean simulations isolating sulfate and nitrate aerosols or do you mean simulations isolating CFCs (Chlorofluorocarbons), a relatively unimportant greenhouse gas-due to its relatively extremely low concentrations in the atmosphere?).

    Comment by Richard Ordway — 24 Apr 2006 @ 8:38 PM

  148. Thank you so much Raypierre for your response to my box experiment[#119]. I would appreciate it if in the future you would have a thread about basic stuff like that. I am a scientist but not a climate scientist; and climate science has LOTS of independent factors and counter-intuitive principles in it. So I, for one, have a steep learning curve here. But maybe this would be helpful for other readers as well? Anyway, thanks again, that was very helpful! And I will happily check out the lit you suggest.

    Comment by ocean — 24 Apr 2006 @ 8:42 PM

  149. Teacher Ocean,

    I’m a former science teacher and thin-films engineer. One problem you will have with your design is convection. Your greenhouse [assuming glass] is like a fat, dual-pained window. Gasses conduct heat between two plates of glass at a rate proportional to the speed of the gas, and less efficiently with greater distance between the plates [the effect also varies in different pressure regimes, it is very efficient at low vaccuum, because gas molecules can travel from plate to plate without being intercepted. At higher vaccuum regimes it becomes less efficient with fewer molecules impinging.]. As Temp is proportional to K.E. = 1/2mv^2, heavier gasses travel slower at the same temp as lighter gasses. Hydrogen cools the best because it’s the fastest [2 g/mol], Air slower [~29 g/mol], Argon slower [40 g/mol], CO2 slower [44 g/mol], and various noble gasses like Radon slower still. As a result, you may have noticed that dual-pained windows filled with Argon are typicaaly thinner than those filled with Air.
    So, if you have two identical glass greenhouses with thermally isolated mercury thermometers at equilibrium in the sunlight [One with Air at Press=P, and the 2nd w/ CO2 at Press=P], and you close the blinds – you will see the thermometer in the CO2 greenhouse retain its temperature longer – not because of any ‘global warming’ type effect, but simply because Air conducts heat to the walls of the greenhouse better than Air does. By the way, 1.5 lbs of dry ice that you used should make about 15 cubic feet of CO2 gas at STP, a lot more than you need in your class.

    I believe the ‘greenhouse effect’ normally associated with CO2 is more of a diffusion problem, rather than a heat sink problem. [i.e. – like a blanket, not a hot water bottle.] It’s not that CO2 ‘holds’ heat like a bank. The CO2 emits any heat absorbed virtually instantaneously – but some portion of the emitted thermal energy goes the ‘wrong’ direction. IR heat energy is absorbed and reemitted numerous times, Since the biggest greehouse gas, by far, is water, why not do your demonstration comparing the transmission of IR heat through liquid water and Air. Compare an empty and a water filled glass container. A thermometer on the other side of the water should take longer to warm up than one on the other side of an empty container, because the heat is having trouble finding its way through the water. [Of course, this experiment is faulty b/c the thermal mass of the water is acting like a hot water bottle…] Conceptually, however, you can show your students the diffusion effect associated with CO2 and H2O, that the heat will eventually work its way out of the water into its surroundings [like heat trapped in a hot rock], and that climate science is a complex endeavor because the CO2 signal is not the sole factor out there.

    Comment by jim edwards — 24 Apr 2006 @ 9:30 PM

  150. Teacher Ocean,

    I’m a former science teacher and thin-films engineer. One problem you will have with your design is convection. Your greenhouse [assuming glass] is like a fat, dual-pained window. Gasses conduct heat between two plates of glass at a rate proportional to the speed of the gas, and less efficiently with greater distance between the plates [the effect also varies in different pressure regimes, it is very efficient at low vaccuum, because gas molecules can travel from plate to plate without being intercepted. At higher vaccuum regimes it becomes less efficient with fewer molecules impinging.]. As Temp is proportional to K.E. = 1/2mv^2, heavier gasses travel slower at the same temp as lighter gasses. Hydrogen cools the best because it’s the fastest [2 g/mol], Air slower [~29 g/mol], Argon slower [40 g/mol], CO2 slower [44 g/mol], and various noble gasses like Radon slower still. As a result, you may have noticed that dual-pained windows filled with Argon are typically thinner than those filled with Air.

    So, if you have two identical glass greenhouses with thermally isolated mercury thermometers at equilibrium in the sunlight [One with Air at Press=P, and the 2nd w/ CO2 at Press=P], and you close the blinds – you will see the thermometer in the CO2 greenhouse retain its temperature longer – not because of any ‘global warming’ type effect, but simply because Air conducts heat to the walls of the greenhouse better than CO2 does. By the way, 1.5 lbs of dry ice that you used should make about 15 cubic feet of CO2 gas at STP, a lot more than you need in your class.

    I believe the ‘greenhouse effect’ normally associated with CO2 is more of a diffusion problem, rather than a heat sink problem. [i.e. – like a blanket, not a hot water bottle.] It’s not that CO2 ‘holds’ heat like a bank. The CO2 emits any heat absorbed virtually instantaneously – but some portion of the emitted thermal energy goes the ‘wrong’ direction. Some small portion of the IR heat energy is absorbed and reemitted numerous times by GHG, and the heat ‘loses its way’ – effectively running around in circles in the atmosphere [‘trapping’ it].

    Since the biggest greenhouse gas, by far, is water, why not do your demonstration comparing the transmission of IR heat through liquid water and Air. Compare an empty and a water filled glass container. A thermometer on the other side of the water should take longer to warm up than one on the other side of an empty container, because the heat is having trouble finding its way through the water. [Of course, this experiment is faulty b/c the thermal mass of the water is acting like a hot water bottle…] Conceptually, however, you can show your students the diffusion effect associated with CO2 and H2O, that the heat will eventually work its way out of the water into its surroundings [like heat trapped in a hot rock], and that climate science is a complex endeavor because the CO2 signal is not the sole factor out there [although one of the only man-made ones – others: water, aerosols, sun, et al]

    [Response: As an addendum to that, though it isn’t possible to make an infrared greenhouse effect analogue easily in the laboratory, it is easy to illustrate the infrared opacity of various materials. For $50 or so, you can get a broadband infrared sensor which you can attach to a volt-ohmeter, whose output will be proporional to the infrared flux. Point it at a candle. It will register high. Put a pane of glass in the refrigerator for a while, then interpose that between the candle and the sensor. It will register low, since the glass is opaque to infrared, and by Kirchoff’s law, also emits like a black-body — at its cold temperature, rather than the hotter temperature of the candle flame. Go out on a hot day. Point the sensor at the asphalt parking lot. Registers high. Point the sensor at the sky, not toward the sun. You’ll see some sign of infrared, which is the downward infrared from the atmosphere into the ground. Now, the best thing would be to be able to take your class into space and point your $50 sensor at the Earth from the Space Station, so you could see that the radiation going out is like a blackbody at 255K instead of the actual surface temperature of the Earth. For that matter, in space, there would be plenty of vacuum to do the glass box experiment properly! –raypierre]

    Comment by jim edwards — 24 Apr 2006 @ 9:36 PM

  151. Re: Jim Edwards: What can I say, that was an awesome explanation and suggestion. THANK YOU. I know I sound like my teenage students. Their language rubs off on me, though I still can’t figure out what “I know, right..” means. But I digress. Your post is exceptionally helpful to me. I will try it out with my summer students :).

    Comment by ocean — 24 Apr 2006 @ 9:50 PM

  152. Wow, thanks to Raypierre again for additional comments. I think Hank Roberts had suggested an infrared camera earlier in this thread. I shall print out this thread and try all this stuff this summer [except the voyage out to space _not that I don’t want to :)] and keep you guys posted on the progress.. Though, if the moderators would let me, I would like to change my handle to “teacher ocean.” Thanks Jim Edwards for the suggestion :)

    Comment by teacher ocean — 24 Apr 2006 @ 10:35 PM

  153. A little OT but,
    I have a question, I hear some folks talking about using greener energy to reduce C02, lifestyle changes etc.etc. What energy would that be? Hydro fundamentally changes land usage, and has a potential to release more methane. Wind, while great, would not do migratory flocks of birds that well. And on top of that if we went to wind power in wholesale fashion, has anyone modeled (If it is even possible) the effects of that much energy extraction from the atmosphere? Tidal Power is not that great for the ocean life in the vicinity of the generator. Nuclear Power while viable has a very nasty logistics tail and health hazard with waste products. Geothermal is a possibility but is not readily available everywhere on the planet. (And again what would happen to earth with that much energy extraction.) Solar again is a possiblity but the issues of placement, land use, effieciency of the cells and energy storage (For a rainy day!) are dealt with properly. (Lead acid batteries aint gonna do it.) I repeat what is viable? All methods have pros and cons? How would lifestyle changes be affected? Drive a hybrid? Don’t make me laugh, those cars (At least in their current iteration) cost more oil energy units than they will ever save! Run on ethanol/biodiesel? Those emit CO2. (They do reduce dependence on oil. Well at least ethanol does.) Ride a bus or train? What if there is no train to ride. (Where I live this is true, out in the boonies.) Stop airtravel as it is very expensive energy expenditure? Stop using computers? Well obviously none of us here are doing that and computers are one of the most polluting things to have! What can we realisticly do as a population to reduce energy expenditure? I am an electrical engineer by education and training, and as such I am used to asking and providing practical answers to life’s problems. I work in digital and telecommuncations, specificlly Internet backbone architecture, so I help make forums like this possible. (I know that networks are definitly not “green”!) Thus, my quandry is not so much about GW and how we may or may not be accelerating it. I am asking how we can practicly go about doing something about it? I also happen to agree with GWB about kyoto, why should we have to limit our economy to try to limit C02 when some of the most polluting countries don’t have to. The net affect on the earth is zero and it doesn’t care if the C02 or pollution is Chinese, European, Indian, or American. Also what is the fundamental difference to sign up to Kyoto and not meet your targets? What difference have you made? None. Maybe this has been addressed but I have not found it? In any case I am asking “What practical thing can we do about it without enormous sacrifice that no country’s population will be willing to accept?”


    [Response: OK readers, you know the answers to most of these questions. Please have a go at helping James out. There’s really no need for him to despair. I’ll contribute my two bits to the effort: (1) You are misinformed about biodiesel. The CO2 released by burning biomass came from the atmosphere, and so is a net wash. There is an issue about how much energy it takes to raise and process the crops. For ethanol there is in deed a big question here, but the DOE study on biodiesel claims that you get 3.5 units of biodiesel energy out for each unit of fossil fuel energy you put in; with better technology and crops, it can ge better. Some Cornell researchers dispute this number, but it’s not at all clear they are right. (2) I do agree about the massive environmental impact of hydropower. Having see what some big dams have done to Swedish Lappland, for example, I feel like trading some of those hydropower projects for nuclear energy might have been a net plus for the environment. –raypierre]

    Comment by James — 25 Apr 2006 @ 1:17 AM

  154. Re #153, A recent report tells us that Ethanol from corn/sugar cane is good but not good enough, however Ethanol from biomass is a very good idea and could provide >20% of the USA’s liquid fuel.

    It all sounds very promising but bear in mind that it can only mitigate Gasoline/Petrol nd not replace it. Still it is carbon neutral.

    Comment by pete best — 25 Apr 2006 @ 9:22 AM

  155. I think the type of alternative energy source would depend on the country and its natural resources. Like in countries that get A LOT of sunshine like Egypt, Israel, Saudi Arabia solar energy could be the best. They have all this expansive desert “wasteland” no one can live on, so solar cells wouldn’t be too “ugly” and one can make huge panels.

    This may sound flippant, but I don’t mean to be. I am asking a genuine question out of ignorance: how are computers one of the most polluting things we have?

    Ok one more country/culture specific thing: in general, Americans use fossil fuels too much compared to most Europeans. It is culturally acceptable, expected even, to share rides and/or ride trains and bicycles in Europe. And most European cities have very organized and expansive public transportation systems.

    Also nuclear power becomes a serious environmental issue only in case of accidents or blatant disregard for waste removal procedures. Of the ones you listed I would say it is the cleanest alternative energy source.

    I’m not a big dam or windmill fan either.

    Comment by teacher ocean — 25 Apr 2006 @ 9:36 AM

  156. Ray pierre, thank you for that bit about bio diesel. A had not seen the latest energy studies for it. The last I had read, you did not get out as much as you put in, and in any case we would still have fossil fuels as the prime energy source. (At least for now.)

    Ethanol, as good as it may be is not a substitue for oil in uses such as for aviation, and marine applications. It would also not be a good prime mover to generate electric power. I agree it is a start, but it only delays the inevitable. The only issue I see with ethanol is that it depends somewhat on crop growth, and fossil fuels are used heavily to make modern fertilizer.

    Comment by James — 25 Apr 2006 @ 9:46 AM

  157. Re: #153

    > I also happen to agree with GWB about kyoto, why should we
    > have to limit our economy to try to limit C02 when some of
    > the most polluting countries don’t have to. The net affect
    > on the earth is zero …

    I disagree that the net effect is zero. As to *why* we should do it … I completely disagree with the whole “why should we do the right thing when others are getting away with doing the wrong thing” idea. Helping the planet so that our children and grandchildren have a better life is a *moral* imperative. Irresponsibility on the part of others is *no excuse* for ducking our responsibility. This whole attitude, I believe, gives real insight into the moral bankruptcy of the Bush administration.

    And, we (by which I mean, the U.S.) are the largest source of CO2 emissions in the world. If we took the lead, setting an example for outstanding moral behavior rather than setting an example of outstanding selfishness, there’d be more pressure on nations like China and India to step up to the plate and do the right thing.

    Comment by Grant — 25 Apr 2006 @ 9:55 AM

  158. Ocean,

    Pound for Pound/ ounce for ounce, silicon chip fabrication is one of the most expensive processes we have of manufacturing anything. You put more manpower, energy, and materials within the silicon manufactering process than any other process. They do not draw much power by size once they are fabricated but the hard part is making them.

    You are incorrect about nuclear power. Once the spent fuel is removed it is active for long long time. Storage is the main issue with spent fuel, and it is the biggest issue that faces nuclear power today. Theft of that material for weapons manufacture, or the seepage of it into your groundwater would not make your day! Lastly nuclear plants are radioactive for long time as well once they are decommissioned.

    On the country culture thing, Europe’s numbers on C02 production are also a half as much as ours is due to the fact that more of their energy generation is based upon nuclear power.

    You are correct we could erect a lot of solar panels in saudi or desert lands, but how would you transport it to the people who need it? Power lines from the Sahara to Europe? How would you store it for long periods of time? Solar works well for small applications, it is very difficult to scale up the operation however.

    Comment by James — 25 Apr 2006 @ 9:57 AM

  159. The real news on the biodiesel front is algae production. The downside of algae biodiesel seems to be NOx emissions, but engineers think this problem is solved with catalytic converters. Otherwise, biodiesel is cleaner than petrodiesel.

    Water is not an issue as algae really doesn’t care too much how brackish the water is. But, algae does need water, lots of it.

    Algea is 30 times more solar efficient than seed crops, and this efficiency is further advanced with genetically engineered algae.

    Algae is very sensitive to rich co2 fertilization, unlike other crops which are limited by other nutrients. Flue gases make ideal environments for algae.

    Algae may have been an important source in the formation of oil deposits. Algae is very rich in oils compared to plant cellulose. Plant cellulose consists of chained sugar carbohydrates and is difficult to breakdown.

    I think Ray is right about biodiesel. Given the current research, oil prices, and state of the art, biodiesel is just about with us. A little google searching and readers might find the topic fascinating.

    Comment by Matt — 25 Apr 2006 @ 12:18 PM

  160. The geothermal flux through Earth’s surface is about 38 TW and it is largely untapped energy except in a few localities where extraction is economical enough to make its use competitive with other forms of energy.
    The amount of thermal energy stored in the upper 10 km of Earth’s crust is huge and extraction of that energy using enhanced geothermal systems (EGS) technology would have no effect on Earth’s thermal field. The heat below the zone from which the energy would be extracted would resupply the energy in a few hundred to a few thousand years after extraction ceased.

    Have a look at for relevant information.


    Comment by Will Gosnold — 25 Apr 2006 @ 12:49 PM

  161. Ethanol is not really “carbon neutral” (#154). Those benefits are overstated. The carbon emitted by burning ethanol still piles up in the atmosphere, and remains there for decades. It doesn’t get used up by “new” plants immediately. Plants would have probably been growing in those areas before it was decided to use the plants for fuel instead.

    We’d be much better off reducing all forms of fuel burning. The transportation industry, in particular, needs to do a major shift away from burning fuels for locomotion and in the direction of using electricity from solar and wind energy instead.

    But because a shift to electricity (or fuel cells technology) is not going to happen overnight, the government needs to get busy in establishing programs that will bring about massive energy conservation now, to reduce the annual amount of GHG emissions.

    Higher fuel prices are already starting to serve this same purpose, but people would much rather have positive incentives than negative one.

    What I have been advocating for is that the federal government establish programs that provides positive financial incentives for using less energy – by driving less, flying less and conserving energy in the home. People are much more likely to accept the idea if they see that they can earn more annual income by reducing their driving and flying and energy use in the home. More details about this concept can be read downloaded from the following web site:

    Comment by Mike Neuman — 25 Apr 2006 @ 1:11 PM

  162. James, as an electrical engineer — come up with a simple device that will prevent devices from consuming parasitic, wasted power from lots of warm transformers always plugged in!!

    A little box that was a true electronic OFF, for example, that would sit at the wall plug. When the television, media center, etc. has cooled off, nobody’s moved for twenty minutes, and nothing’s being consumed but the 15 watts of power designed to save the homeowner two seconds’ warmup wait when he arrives home eight hours from now — shut off the electricity.

    When the homeowner comes in, and touches the ‘on’ switch, your new box detects that and allows power through again.

    Yes, for some primitive devices the @*$%& clock goes 00:00:00 but I think the total electricity saved from avoiding “always on” needless power is calculated to be astonishingly large.

    Comment by Hank Roberts — 25 Apr 2006 @ 1:49 PM

  163. Grant,
    I believe that we as in the US will soon be eclipsed by China as the number one C02 producer. And how often has the Chinese government really cared what anyone outside of China thinks? When was the last time the Chinese bowed to external pressure? Have you been to China and seen how smoggy it is?
    Your problem is you are confusing morality with reality. Whether or not it is morally right to join Kyoto(Table that for now.) what affect will it have on the world ecology. If it does nothing/very little why do it? If their is a tangible benefit then great. Or for a better analogy, if you did not get paid would you go to work? Upholding morals can be great but you can’t forget the real world when you do so. Also do not overlook your own lifestyle when condeming others. As an American how would you have moral grounds to be condeming America even though you are a part of the problem? (You are an American after all.) What are you doing to fix it? What am I?
    My point is morals can be good but the actions must also have meaning and must also be worthwhile/feasible. Have you ever tried to eat a moral?

    Comment by James — 25 Apr 2006 @ 1:52 PM

  164. Hank that is wishful thinking!
    How would my new box detect you pressing the on button if it did not in turn use power? Telepathy or body language?
    What you are talking about is standby power wastage, and it is very significant loss. But you can’t have it both ways, technology helps you (ie having a remote control)but it requires energy. No energy equals no technology or technological assistance. If you are worried about standby power buy a power strip with an on/off rocker switch, or throw the breaker to your house main when you leave! Nothing needs to be invented, existing technology just needs to be used, and as individuals this would probably be the easiest thing we could do!(I would invent your “box” but some “switch” guy thought of it first!)



    Comment by James — 25 Apr 2006 @ 2:11 PM

  165. Re 153 – Raypierre’s comments:

    I am interested to hear some positive thoughts about biodiesel. I have spent some time recently reading about biofuels, for a biofuel discussion paper I wrote for an organisation I am involved in (see – attached under ‘Activists Portal – Biofuel Paper’). There is no doubt some potential for vastly more efficient biofuels, which are not yet commercially available. The information I could find on US bioethanol is not encouraging – according to a recent University of Berkley study (see here Source: ), US bioethanol has 13% less greenhouse gas emissions than diesel or petrol, because of the energy intensive refining process, the energy input to farming, and fertilizer production and use. There would be no positive balance at all unless all bioethanol by-products were counted as feed-stock replacement, and nobody knows if that is happening, let alone 100%. The European biodiesel balance is slightly better, it seems, although a lot of the studies ignore N20 amd CO2 emissions from soil as fertilizer is applied. The most concerning issue, however, is that tropical biofuels have an inherent competitive advantage over those grown in Europe and most of the US. This is because you can get far more energy from crops grown in the tropics, on the same size of land, and for the same inputs (biodiesel from algae would be different, but is only at the R&D stage). Indonesia and Malaysia have already condemned millions of hectares of rainforest to destruction in order to produce biofuel from palm oil for Europe and other markets. Brazil is about to export biodiesel made from soya – and soya is the largest single cause for Amazon destruction at present. The CO2 emissions from further Amazon destruction and more rainforest and peat swamp destruction in south-east Asia could be absolutely massive – satellites have linked palm oil plantation owners to 75% of the massive annual peat fires on Borneo, which emit vast quantities of CO2. And IPCC data suggest that N2O releases are far higher where nitrogen-fertilizer is applied to tropical soil compared to temperate soil – yet I am not aware of any full assessment of all emissions, including from soils, for any of the rapidly expanding tropical biofuel crops.

    I am very worried indeed about biofuels, unless we had mandatory certification based on good studies of life-cycle greenhouse gas assessments.!

    Comment by Almuth Ernsting — 25 Apr 2006 @ 2:43 PM

  166. I unplug my trailer when I leave town or the state, but that won’t work on a more temporary basis. Not if you want your phone to work while you’re out. Kyoto continues to be a straw man because of China, Australia and the US. Until these top three sign on it’s moot.

    Comment by Mark A. York — 25 Apr 2006 @ 3:24 PM

  167. James — no need to reply to this, you asked for ideas. What I suggest isn’t trivial nor impossible, though, just FYI a quick Google gave this magnitude:
    “At least 11 % of the electricity consumed in German households and offices is used by temporarily unused equipment running in stand-by mode.”

    I’ve seen similar figures for the USA. Many devices now exist that run at 10% power all the time and don’t even have a true electrical “off” switch to kill that “feature.”

    I know it’s possible to detect human presence with little rechargeable-battery devices (motion, infrared, sound, capacitance). Combined sensors are becoming cheap. Low power devices can switch high power circuits. So what I suggest isn’t impossible, in fact it’s done all the time, albeit not to save energy. Could it be?

    Just a thought. In our house we went and bought metal-box power strips to shut off anything built to stay “always on” — no big deal. But many people don’t do that.

    Comment by Hank Roberts — 25 Apr 2006 @ 3:40 PM

  168. Comments on Andy Revkin’s latest piece (ref. #62, #76, #94).

    Global warming’s PR problem
    By Andrew C. Revkin The New York Times

    SUNDAY, APRIL 23, 2006


    Global warming has the feel of breaking news these days.

    Polar bears are drowning; an American city is underwater; ice sheets are crumblingâ?¦..

    Between the poles of real-time catastrophe and nonevent lies the prevailing scientific view: Without big changes in emissions rates, global warming from the buildup of greenhouse gases is likely to lead to substantial, and largely irreversible, transformations of climate, ecosystems and coastlines later this century.

    … few scientists agree with the idea that the recent spate of potent hurricanes, European heat waves, African drought and other weather extremes are, in essence, our fault. There is more than enough natural variability in nature to mask a direct connection, they say….

    While scientists say they lack firm evidence connecting recent weather to the human influence on climate, campaigners still push the notion….

    This is a misleading article by Revkin, who seems to be arguing that global warming deserves only the “feel” of being a breaking news story today, and no more. His article contributes to the erroneous conclusion that global warming is still some far off problem, a problem that won’t happen until much later in the century. He buys into the global warming skeptics’ ridicules conclusions that all the weather-related devastation of late (Hurricanes Katrina, Rita and record number of more stronger storms in 2005), Europe’s deadly heat wave of 2003, Africa’s drought, record high global land and sea temperatures, polar ice and mountain glaciers melting …) is no more than natural variability.

    Incidentally, Revkin’s conclusions are in direct conflict with what Greg Holland, a division director at the National Center for Atmospheric Research in Boulder, Colorado, said at yesterday’s American Meteorological Society’s 27th Conference on Hurricanes and Tropical Meteorology in Monterey, California on Monday (April 24): that the wind and warmer water conditions that fuel storms that form in the Caribbean are “increasingly due to greenhouse gases. There seems to be no other conclusion you can logically draw.”

    Holland said that the tropical storm anomalies in the 1940s and 1950s can be explained by natural variability, but that the increasingly higher CO2 levels in the atmosphere began to change the regular patterns of hurricane development in the Caribbean in the 1970s, and that by the early 1990s, the changes in the atmospheric began affecting the storm numbers and intensities.

    “What we’re seeing right now in global climate temperature is a signature of climate change,” said Holland. “The large bulk of the scientific community say what we are seeing now is linked directly to greenhouse gases.”

    Revkin only adds to the misinformation by reporting on the conclusions of federal agency researchers (those who remain in their jobs) who support the administration’s position on global warming.

    I was not surprised by Revkin’s acceptance of the remaining (still employed) Bush administration’s scientist’s opinion, that there is insufficient basis to ascertain if global warming is the reason we are seeming more of these increasingly costly and life-threatening hazards of nature, or if maybe it’s just normal climate variation in the system.

    The reason I say that is that Revkin apparently didn’t find reason enough to report on the Bush administration’s firing of my brother, after I had sent him the documentation that accompanied NOAA’s removal of my brother from the National Weather Service for his 2003 press release documenting the effects of early snowmelt and spring flooding on Midwest flood prone areas, unquestionably due to anthropogenic global warming.
    See here

    [Response: I think you are mischaracterising Revkin’s views. There is a difference between being able to assign a formal attribution for changes in weather statistics as a function of cliamte change, and saying that every bit of unusual weather is caused by climate change. The former is a difficult thing to do, the latter a very easy thing to say. – gavin]

    Comment by Mike Neuman — 25 Apr 2006 @ 4:08 PM

  169. Re #153:

    (1) What is your source for claiming that hybrids cost more energy than they save? The energy needed to run a car is much larger than the energy needed to produce one and it is not even clear that a hybrid will require much more energy to produce (yes, it has an electric motor and some nickel-metal hydride batteries but it has a smaller energy too). So, I doubt your claim is true.

    (2) I don’t understand the logic of saying, “I don’t see what technology will save us, so therefore the only solution is to let everyone continue to use the atmosphere as a free sewer for greenhouse gases.” I am a big believer in the idea that if you start making people pay the costs of the greenhouse gases they pump into the atmosphere, the market will develop the technologies to minimize (or sequester) those emissions. That, to my mind, is probably the more important purpose of something like Kyoto (imperfect though it may be), rather than the achieving specific emissions targets in the 2008-2112 time period.

    Comment by Joel Shore — 25 Apr 2006 @ 4:37 PM

  170. Re biodiesel: biodiesel sounds promising but there appear to be a couple of problems. There are two crops that are being investigated for really large scale production, soy beans and palm oil. On the surface, soy looks like an ideal candidate since it is a legume and thus should not require chemically fixed nitrogen. Unfortunately, most of the soybeans now grown are “roundup ready” and the high levels of roundup sprayed on the crop greatly diminishes the amount of bacterial nitrogen fixation. Another crop being studied is palm oil. Vast tracts of forests in Indonesia are being burned to make way for plam oil plantations. This is not very kind to local environments.

    The best biofuel is still ethanol from corn but it has to be part of an integrated production facility which should include the following steps: cattle feed lot, feed all waste (distiller’s dried solids) to the cattle, convert the cattle waste to methane to supply part of the energy source for the distillation, burn the dry crop waste to provide the remainder of the energy, irrigate the crops with the effluent from the methane digestor. An integrated plant should be economical from both an energy and fiscal point of view.

    Comment by Ian Forrester — 25 Apr 2006 @ 4:47 PM

  171. Re #170: Locally the chosen crop for biodiesel is going to be canola, that is, rapeseed. The state gvnmt is going to help with $$ to build a processing plant. The local farmers, of course, helped to provide political support for this for two reasons: (1) They really need another cash crop as the current ones have rather depressed prices. (2) Diesel fuel is a big part of their production costs.

    Comment by David B. Benson — 25 Apr 2006 @ 4:59 PM

  172. If you want a short perspective on renewables, I have a post up on the MaxSpeak blog, run by an economist acquaintence of mine.

    Comment by Gar Lipow — 25 Apr 2006 @ 5:02 PM

  173. Regarding #153
    Compare a toyota prius to a toyota corolla.
    The prius is twice as complex to make. As such it requires more energy units to design, fabricate jigs for parts, and manufacture and test. Once deployed the car gets 52MPG best case, against 38MPG best case for the corolla. (However the corrola gets closer to best case than the prius as the prius depends on “city” driving to get close to 52. And I have several friends who have them and they hardly get over 42MPG.) Every so many thousands of miles the car needs a new battery pack, it is more work to maintain, etc.etc. Each of those activities over the life of the car costs energy. (Man hours are energy too, after all you have to pay, clothe, feed, and transport the technician who fixes it.) I never said that a hybrid is less of an impact than an SUV, but between similar car types the first iterations of hybrids are a net wash as far as energy expenditure over the life of the vehicles. No source, just common sense.
    Regarding the second bit of your post. If you are such a big believer in paying the cost, what are you doing to use less energy? I am not saying let’s have fun and party, what I am saying is that a blue sky solution to hour energy needs will not work.(Obviously) Our energy production has to be based upon sources that are scalable, (No cottage industry power schemes) and simply workable. I have already expressed doubts in wind,hydro,tidal and solar, they all have undesirable qualities. I hate hearing people say we must do this or that to reduce C02, but they don’t list a feasible alternative to it, what is the point? Some folks even have to the gall to get on everyone else’s case about GW when they are not doing anything about it themselves. Sure you may drive a hybrid, but what about that house where you keep the AC set at 70 degrees in high summer. How are you helping again?
    Someone in here said that given the right market signals the engineers and scientests will respond. (Raypierre I believe.) As one of those engineers I am telling you, we (As in the entire world.) have built our entire society upon fossil fuel based energy. Here and there we have found small niche solutions, but nothing that scales up as required. (Only Nuclear, but nuclear has a long logistics tail due to the life of spent fuel and the issues with creating that fuel in the first place.) Somebody here mentioned hydrogen, and fuel cell based approaches for cars. Not yet good enough I am afraid. The energy storage density in these solutions is much less than fossil fuels and with what energy source do you manufacture the H2?
    I say we should reduce emissions in an economically feasible way now, just becuase it makes sense. Any other way and the world’s population will not accept the sacrifice that drastic measures will require. (I don’t know if I would, would you?) Just like we should not try to pollute the same water we drink from, it just makes sense.

    Comment by James — 25 Apr 2006 @ 5:36 PM

  174. Re 167.

    Again you are attempting to fix the problem of standby power loss with a device that consumes power! Sure it is less power, maybe even an order of magnitude (that is being VERY generous.), but it does not eliminate the problem by any means. Even if it is a little battery it still takes power. I build devices like this for a living, and yes smaller currents/voltages can switch larger ones, but even in the off position silicon switches consume power, when they switch they consume power,when they are one they consume power, (Silicon leakage ring a bell?) the control circuity consumes power. If you use eletromechanicl switches they consume even more power to switch as you have to energize an electromagnet to do so. All you are doing is taking the remote-control circuitry out of the TV and placing it on a power strip! Not very novel idea there. I agree that standby power wastes a lot of energy, so throw the breaker to your house when you leave.

    Comment by James — 25 Apr 2006 @ 5:43 PM

  175. The discussion in #168 is very interesting. Gavin, you might like to have a careful think as to whether you actually want to say Revkin’s view is right. I think that the way you summarised the situation in your comment on #168 is absolutely correct. But the quote from Revkin given in #168 says something very different and illustrates a common error in reasoning which often appears in discussions of climate change and weather events.

    Looking at the Revkin quote, first we should note that he is attributing this view to scientists rather than himself so it is important that scientists be clear whether or not they support what Revkin is saying. Revkin says:

    … few scientists agree with the idea that the recent spate of potent hurricanes, European heat waves, African drought and other weather extremes are, in essence, our fault. There is more than enough natural variability in nature to mask a direct connection, they say…

    Revkin is confusing 1) actual causality in the physical world (whether weather events are “essentially our fault”) and 2) our ability to attribute whether or not individual weather events are our fault. These are two different concepts. Revkin has assumed that because it is difficult to prove causality (concept 2) this establishes that there is no causality in the real world (concept 1) and that extreme weather events are not our fault. This is a simple mistake in reasoning. The inability to prove whether something has occurred in reality does not establish that it has not occurred.

    Looking at it in this way we are left with a statement along the lines that “Few scientists agree with the idea that individual [extreme weather events] can be absolutely proved as being caused by us. Climate science says that extreme weather events are likely to increase because of climate change. Extreme weather events are increasing.”

    Or if you really want to be blunt about it. “There is general evidence to suggest that climate change will cause more extreme weather events and few scientists agree with the idea that it can be proved that individual [extreme weather events] are not being caused by us.”

    Comment by Paul Duignan — 25 Apr 2006 @ 5:47 PM

  176. Re 176.

    I don’t quite buy what you are saying. I agree with Gavin here.
    It is quite easy to claim anything. If GW is/was causing more hurricanes, then why the lull of hurrincanes in the 70’s and 80’s?
    I can claim the GW is causing more hurricanes. I can also claim that I won the Nobel Prize, but until I show you the prize have I won it?

    Comment by James — 25 Apr 2006 @ 5:59 PM

  177. James (comment #177) I agree with you that I would be making a very academic point if no climate scientists were suggesting a general connection between hurricanes (and other extreme weather events and climate change). But they are (for instance see todayâ��s story on CNN outlining Greg Holland’s argument that there is a connection: So to my mind this issue does not fall into the category of it being an arbitrary claim about causality without any basis or in your words it being a case where it is “quite easy to claim anything”.

    If climate change does in fact cause an increase in hurricanes then in the early stages of this manifesting we would see exactly what we may be seeing now – a true causal connection being “masked” (in Revkin’s words) by normal variability. Today on CNN Greg Holland is claiming to have “unmasked” it. The fact that it has not been unmasked to your or my satisfaction prior to now says nothing about whether or not the causality is already operating. Often in high risk situations you don’t have time to wait until the causality is fully unmasked. Where you identify a trend (even though still within the limits of natural variability) in the direction of suspected causality, it is entirely rational to take precautionary steps on the basis of an assumed causality and then review your position when the situation clarifies. Otherwise you doom yourself to having left it too late to act simply on the basis that there is natural variability in an outcome you are interested in. All I am arguing for in my comment (#176) is that the actual logical position about causality and proof of causality be stated accurately (I don’t think that Revkin did this, while I do think that Gavin did) so that stakeholders can make their own decisions about what action they think they should take now to manage the potential risk.

    Regarding the Nobel Prize, I’d actually accept that you had won it the moment I saw it reported on CNN rather than having to actually get you to show it to me. But the difference between the Nobel Prize and hurricanes is that it is a one off event and not subject to natural variation in the same way as hurricanes are. A better analogy would be if prior to winning the Nobel Prize you had between 1 to 3 job offers a month. Some social scientists present an argument that there is reason to believe that winning the Nobel Prize is likely to influence the likelihood of universities making job offers to you (although they say that in the case of any one particular job offer they will not be able to absolutely prove this). So far in the three weeks since winning the prize you have had 3 job offers. Would you insist that there’s absolutely no reason to believe that that at least some of the three universities offering you jobs in the last month have been influenced by the fact of your wining the Nobel Prize?

    Comment by Paul Duignan — 25 Apr 2006 @ 7:02 PM

  178. James said, in part: You are incorrect about nuclear power. Once the spent fuel is removed it is active for long long time. Storage is the main issue with spent fuel, and it is the biggest issue that faces nuclear power today. Theft of that material for weapons manufacture, or the seepage of it into your groundwater would not make your day! Lastly nuclear plants are radioactive for long time as well once they are decommissioned.

    and it seems that the United States’ representative democracy is no more capable at arriving at a sensible compromise solution for the siting of nuclear waste than it is when siting offshore wind farms. see here for some details. indeed, the biggest obstacle to nuclear power is not at all technology or means of storing nuclear waste, it’s that no politician wants to support siting a storing facility in their state, no matter where it is. in short, we’ve lost any sense of a commons. (additional reference here)

    Comment by Jan Theodore Galkowski — 25 Apr 2006 @ 7:54 PM

  179. James point about hybrids is extremely hand wavy. And no James, it is not obvious that the energy cost of the Prius is greater than that of the Corrola. Got anything numeric on that or it just a WAGNER? )Wild assed guess, no explanation necessary(

    Comment by Eli Rabett — 25 Apr 2006 @ 8:25 PM

  180. According to Kerry Emanuel of MIT while overall cycone activity hasn’t increased, (includes the Pacific) North Atlantic Hurricane activity has and because of heating of the water via global warming.

    Sounds right to me.

    Comment by Mark A. York — 25 Apr 2006 @ 8:26 PM

  181. Regarding Mark’s comment (#181) presumably referring to mine and James’ (#176-178) I was just being sloppy in my wording when I said “an increase in hurricanes”. I mistakenly implied that someone is claiming that hurricanes are increasing in frequency. Whereas as I understand it, some climate scientists like Kerry Emanuel are arguing that they are increasing in intensity but not frequency.

    Comment by Paul Duignan — 25 Apr 2006 @ 10:01 PM

  182. Re #174: I agree with Eli. Waving your hands and saying “it’s common sense” does not an argument make with respect to hybrids. Some of your facts are also questionable. First off, the Prius has only a little less interior room than a Camry, so it should probably be compared to something in between a Corolla and Camry. Second, the battery packs are expected to last about 150,000 miles or more…which will be the life of the car for many people. Thirdly, it is not that hard to get around 50-53 mpg in the Prius when the climate isn’t too cold; the cold Rochester winters (and short times of most commutes around here) do lower the mileage a fair bit, although my lifetime mileage after 2 years is ~46-47 mpg. [And, by the way, in practice I find that the Prius highway mileage is just about as good as the city mileage if you keep your highway speeds around 60 or so. Once you start getting up around 70-75, it begins to drop off more significantly.] Fourth, the Prius does not need much, if any, more maintenance than any other car; Sure, there are some extra things like an electric motor but so far those have proven quite reliable. And, wear-and-tear on the engine and on the brakes are reduced somewhat.

    I agree with you that it is necessary to think about all one’s actions with regard to energy…and, yes, it is silly to keep the A/C set at 70degrees. (I don’t even have A/C in my apartment.)

    As for your arguments about how we have built our society on fossil fuel based energy: Well, that is the whole point. When you don’t send the market the right signals (i.e., by allowing the costs of fossil fuel energy to be externalized) then you don’t magically get the other technologies that could compete with it if those costs were internalized but can’t when they’re not. [And, you also get a lot of waste of energy…One of the biggest sources of energy is what Amory Lovins calls negawatts…i.e., energy saved due to efficiency improvements.]

    Comment by Joel Shore — 25 Apr 2006 @ 10:01 PM

  183. Toyato has announced a hybrid for 2008 that will get 113 mpg, using lithium batteries. It will be introduced to the European market in 2008.

    I drive a VW diesel bettle, rarely going over 60 mph, and it gets 55 mpg. A diesel hybrid with lithium batteries would totally kick ass.

    Comment by Mark Zimmerman — 25 Apr 2006 @ 11:27 PM

  184. Re: #163

    I believe that we as in the US will soon be eclipsed by China as the number one C02 producer. And how often has the Chinese government really cared what anyone outside of China thinks? When was the last time the Chinese bowed to external pressure? Have you been to China and seen how smoggy it is?

    I still maintain that what China chooses to do or not do, is irrelevant to the proposition that securing a better world for future generations is a moral imperative. I’m assuming that you agree; correct me if I’m wrong.

    And, even if we assume that China’s only motivation is greed and self-interest, they don’t operate in a vacuum. They depend for their prosperity on foreign markets, and do respond to pressure when they see it as in their economic interest.

    Whether or not it is morally right to join Kyoto(Table that for now.) what affect will it have on the world ecology. If it does nothing/very little why do it?

    I strongly disagree that reducing CO2 emissions by the U.S. and other willing nations will have no impact. Study of the SRES scenarios indicates that future temperature change and sea-level rise will be less, the less CO2 we put into the atmosphere now, even within the limits of practical possibility. And, it’s basic physics: more CO2 means more warming. We’ve already witnessed impact due to the warming of about 1 deg.C since pre-industrial times; every bit of further warming exacerbates the problem. And since impacts are likely to depend on temperature in a nonlinear way, the difference between 3 deg. and 4 deg. warming could make a huge difference in quality of life.

    Also do not overlook your own lifestyle when condeming others. As an American how would you have moral grounds to be condeming America even though you are a part of the problem?

    First of all, this is an ad hominem attack. Second, criticizing one’s country when it’s on the wrong moral path is one of the highest acts of patriotism.

    [Response: China and India do not overwhelm the first world emissions, so what the developed world does definitely has an impact. Further, people shouldn’t dump on China so much — they have made modest efforts with som success at reducing GHG emissions, and have explicitly put it in their five year plan to do more. That’s more than the US has done. Right now the CO2 per unit GDP is so much higher in China than the US that they can grow their economy significantly without increasing emissions, just by approaching US (let alone European) CURRENT levels of efficiency. Tech transfer will help that, as will new technology developed in the West in response to Kyoto and things like it. The one legitimate concern in all this is the possibility that energy intensive industry would simply move from Europe to China in response to Kyoto. There’s no clear evidence that this will really happen — China is more interested in the higher profit margin stuff — but a better treaty, like the next one coming up, ought to deal with the issue. –raypierre]

    Comment by Grant — 26 Apr 2006 @ 12:22 AM

  185. The interesting thing to me is that this story (the Vadon and Cox BBC show with the adversarial title “Battle for Influence”) began as two successive programmes stripped away the context we tried to build around the Stainforth results. First, there was a documentary, hosted by Ian Stewart, in which I was asked about our results and the coverage (specifically the godawful Metro article). In the interview he mentioned the 11 degrees bit and we chatted for a while about how that was a very long term figure (such a climate sensitivity would require a very long time to come into equilibrium) and how we gave no odds at all of that being the case. As Raypierre said, the point was that physics alone didn’t rule out high S. I thought Ian did a pretty good job, but was a bit worried that the press release was being treated as though it were a standalone document, when that isn’t how the press coverage over Stainforth et al worked (we had a big press conference and spent a lot of time on phones over the ensuing days).

    After that show aired, Vadon & Cox interviewed me (though they gave me a false idea of what they wanted to talk about, and refused to release the tape of that interview to us). They banged on about the Stainforth et al press release, and were completely uninterested in hearing anything about how hard we tried to give context to the results. They then read/emailed the press release (or bits of it, in some cases) to scientists, who objected. This removed the press release even further from the wider context. The fact that a year and a bit after the press release Myles and Fiona Fox can get quite a few journalists who were present to say that they remember that we did provide a context for the results suggests to me that we were actually pretty successful in avoiding alarmism. Only two journalists actually wrote alarmist articles, and one of these (at least) had a long conversation with Sylvia Knight in which Sylvia told her (the Metro journo) exactly what was wrong with the story. The journalist went ahead with the article anyway. [I believe, though am not sure, that something similar happened with the AP guy.]

    Basically, we tried to talk to anyone who wanted to write an article about that paper. We had limited input into the press release, which is necessarily short, and tried as hard as we could to provide additional context beyond both the paper and the press release so that people wouldn’t make the kind of mistakes that Metro made. Vadon & Cox, on the other hand, went to great lengths to concentrate exculsively on one or two sentences in the press release. This stripping away of context is a fairly common piece of journalistic dodginess, but it was particularly irritating given that the team (esp Myles and Dave Stainforth) had actually tried really hard to embed the results in a reasonable sort of context.

    It’s true that we could have done things better/differently (chief among them would be not to have done the Vadon/Cox interview). And as I said to Ian Stewart, along the way we’ve probably learned a thing or two about writing press releases. But it’s kind of alarming how an 18 month old press release can take on its own mutant life, reanimated by BBC hacks whose entire body of relevant scientific information has been gleaned from the blogosphere (including the not uncontentious, which they approvingly cited).

    In one sense, this is actually quite a positive development: instead of squaring off Myles or Gavin against (say) Fred Singer, journos of the adversarial sort are trying to square Myles off against Gavin (say). These arguments are about the tails of a distribution – say 10% (max) of the distribution for S – we pretty much all agree about the first 90% of it. Though this ought to be a welcome development, it does worry me a bit that these sorts of programmes (and web discussions!) might serve to exaggerate the level of disagreement (or the perception of the level of disagreement) among the scientific community. Learning how to deal with that, as well as dealing with the media and general public, might be a whole new challenge.


    [Response: Dave, Thanks for your thoughts. For the benefits of any readers who have made it down this far, I should stress that the degree of disagreement between Myles and I on the substance of this issue is extremely small. -gavin]

    Comment by Dave Frame — 26 Apr 2006 @ 2:08 AM

  186. With respect to 181, if global warming increases sea surface temperatures which contribute to an intensification of tropical cyclones, then storms with winds below hurricane intensity will more frequently attain hurricane status (~100 kph winds). Thus the frequency of hurricanes will increase. The frequency of tropical cyclones may not.

    [Response: The issue is whether this would be a detectable effect. Changes near the tail are large for a small shift in the mean. Changes near the middle of the distribution are much smaller. -gavin]

    Comment by Eli Rabett — 26 Apr 2006 @ 2:11 AM

  187. We can argue among ourselves regarding amelioration or adaptation or as to whether one alternative is more efficient than the other till we are blue in our collective faces. The real issue is population. Until we address this one, we are rearranging the deck chairs.

    Comment by JAC — 26 Apr 2006 @ 4:15 AM

  188. “Global Heating”? In a letter in today’s New York Times responding to the Revkin article, a New York advertising executive advises switching from the phrase _global warming_ to the phrase _global heating_. He says that GW doesn’t sound threatening enough, and that GH is “no less accurate, but sounds more distressing and might help focus attention.” If scientists were to decide to buy this idea, they would be joining the category of people who look for sound bites — a category that many in science have good reason to abhor. Nevertheless, if scientists were to judge that a suggestion like that one has merit for more clearly conveying physical reality to the rest of society, I’d hope they’d switch to the suggested phrase despite their natural, and in some ways admirable, distaste for the way the extra-scientific marketplace of ideas actually works. The truth is more important than scientists’ self-image.

    Comment by Steven T. Corneliussen — 26 Apr 2006 @ 6:12 AM

  189. All this talk about saving energy, cutting CO2 emissions, etc. has made me curious.

    I drive a 1995 Ford Contour and it has 65,000 (original) miles on it. I commute 3 miles each way to work (our sidewalk system stinks and I’m afraid to walk or bike, I do not have bus service so, drive I must). But that’s not the curious part (I hope).

    I was wondering what others out there use to commute and the distances that are required. Does anyone telecommute? How many of you are hybrid drivers? Dedicated bicyclists?

    Do any of you use alternative power sources in your homes (solar, geothermal heating, wind power)?

    Comment by lisa brooks — 26 Apr 2006 @ 6:36 AM

  190. Re #154 and windmill damage to birds. I am an environmentalist, I want wildlife to be protected. But, and I say this with all due consideration, SCREW the birds! We can come up with some kind of cage or something around the blades to protect the birds. But the windmills killing birds does far less damage to the environment than a comparably sized (in terms of power output) coal or nuclear power plant. Yes, all methods of generating energy have bad side effects. But they don’t have EQUALLY BAD side effects. I’d rather have the windmills, dead birds and all. Doing without power generation is not in the cards for any sane modern society.

    Comment by Barton Paul Levenson — 26 Apr 2006 @ 9:36 AM

  191. Re: #189

    Senator Barbara Boxer (California) has suggested replacing the moniker “global warming” with “climate crisis.” General Wesley Clark has worked hard to emphasize that global warming isn’t just an environmental issue, it’s a national security issue. Both strategies are designed to emphasize that the problem is far more threatening than the phrase “global warming” alone implies.

    Re: #190

    I telecommute. It saves a *lot* of energy and a lot of time — and I prefer working near my own kitchen! I lived in Boston for 15 years, and took public transportation everywhere.

    Of course (as James has pointed out) that option isn’t available to everyone. I think this underscores the value of government investing heavily in improving public transportation.

    Comment by Grant — 26 Apr 2006 @ 10:20 AM

  192. Pat – re 94 –

    I would observe that science has thus far failed to inform society effectively of the catastrophic climatic destabilization that its conduct is making more likely.

    That failure is not for want of endeavour or funding, but rather to my mind is a matter of method and of language.

    In terms of method, the negative hypothesis of a BAU doubling of CO2 had to be the starting point, but once this was proven (if not by IPCC 1, then to the extent of last year’s joint statement by the world’s 11 leading National Science Academies) there was surely a need to provide projections based on a positive hypothesis of cogent action being instigated, as the means of defining for society just what those cogent actions consist of.

    The policy framework of the requisite Treaty of the Atmospheric Commons is known as Contraction & Convergence, (C&C) and has been widely endorsed over the last 16 years. (See ).

    No other coherent proposal of the requisite framework has arisen and survived diplomatic ‘peer-review’ in that period.

    What is now required is a projection founded on the hypothesis that C&C is adopted as the efficient & equitable basis of negotiations for a treaty to succeed Kyoto.

    To stay within 2oC of GW, the dates of Contraction (of global GHG outputs to cease adding to airborne concentrations)
    and of Convergence (to international per capita parity of emissions rights) become the twin variables sought.

    In providing such a projection, science would be facilitating the necessary action to forestall the threat it observes.
    Given that the duty of science is not merely of warning, but of triggering an effective response, the provision of this projection can be seen as the neccesary role of concerned scientists.

    With regard to language, informing people and governments of probabilities of single digit global temperature rise has plainly failed to communicate the threat we face. (As was predictable decades ago).

    Again, it has to be observed that science has thus far failed in its aspiration to serve society effectively in this context.

    Correcting this failure is, to my mind, about quantifying the climate impacts’ damages in a scale which plainly does not relate geometrically to average global surface air temperature.

    For global damages to be projected sensibly in that scale, it may be that the UN’s “purchasing power parity” filter should be applied to reflect the local values of threatened infrastructure, livelihoods & lives.

    Given that neither of these two critical issues of method and language have yet been visibly addressed by scientists, I’m forced to ask whether science is, in effect, content with its Business As Usual failures, or whether these options will now be addessed ?



    Comment by Lewis Cleverdon — 26 Apr 2006 @ 10:33 AM

  193. James is indeed engaging in handwaving when he says, “The prius is twice as complex to make. As such it requires more energy units to design, fabricate jigs for parts, and manufacture and test.”

    The Prius I was a from the ground-up design effort, but the Prius II was not. Toyota’s goal was to reuse as many parts as possible from another sedan (not the Corolla, sorry, I don’t remember which). This greatly cut the design, tooling, and production costs.

    Regarding birds and wind turbines, modern turbine designs and the use of pre-siting surveys and mortality monitoring while wind farms are being operated has drastically cut the problem.

    Altamont’s the site of the famous “raptor blender” windfarm example. This area’s used by raptors in their daily routine, as they fly from roosting and nesting territories to feeding territories, etc. The original turbines were built on derrick-like structures, which provide perches for perch-hunters like red-tailed hawks. Not good.

    The latest turbines installed in the area kill far, far fewer raptors, and the older, more deadly turbines are being entirely replaced (if they’ve not done so already).

    Trends have been towards larger wind turbines, and modern ones are mounted on tubular columns rather than derrick-like towers, and these both turn out to apparently reduce lethality, as well.

    Monitoring can tell us when lethal striked are most likely. Depending on placement, this might be during migration, or might be during the nesting season. Operating hours can be modified to take such things into account.

    Comment by Don Baccus — 26 Apr 2006 @ 11:33 AM

  194. There is finally some public transportation available where I live, so I use that when I can. But it isn’t just what we as individuals can do, it is what the government can do. If public transportation were more available, most people would take it. If government money were invested into developing alternative energy resources rather than fighting wars for oil in countries where the US doesn’t belong, we would have fewer emmissions to the atmosphere.

    About wind power. I have a lot of affection for birds. I also have a lot of affection for deer but they are the most common road kill from vehicles powered by fossil fuels :). I agree with grant that perhaps we could build fences around windmills and cause less damage to birds. But burning fossil fuels causes birds and other wildlife more damage in the long run.

    Comment by teacher ocean — 26 Apr 2006 @ 11:44 AM

  195. With regard to the discussions of how to reduce CO2 emissions, would it good for RC (or similar) to invite a series of posts from experts in the relevant fields (both pro and con say for each technology or approache)?

    Maybe some discussion from people who have a broader knowledge across the fields of energy – people who have researched this stuff. I know some post in the comments but a set of proper postings or a whole blog dedicated to the subject may help?

    I realise other blogs cover these issues, but as RC is dedicated to the science, I thought one with a similar ideal of focus would be good.

    It might be a good way to help keep moving the discussions on and address what are now becoming, what seems to me, to be the new set of objections (for want of a better term) to AGW – that of “there’s nothing we can do about it”.

    [Response: We focus on the climate science. We tend to avoid policy, or how-to-reduce CO2 type stuff – William]

    Comment by Adam — 26 Apr 2006 @ 11:45 AM

  196. Re #168, Mike, I follow this approach. All weird weather since, say 1990, I attribute to GW, unless the scientists can prove at .05 p significance level that it is not due to GW. So, for me, even Hurricane Andrew in 1992 was a sign of GW. This wouldn’t stand in a court case (and whom would one sue? All of us?), but that’s the way I think about it, and that’s the way policy people should think.

    When in 1990 (well before AGW reached sci certainty), I heard that more intense & frequent storms may be expected with GW (as well as many other problems), so I started reduce my GHGs then, with the idea of reducing those future harms.

    So now scientists have found (surprising even for me) that GW has been increasing hurricane intensity for decades. So the policy idea is to greatly reduce GHGs so as to reduce future hurricane intensity (& use savings from those reductions to storm-proof buildings). Also it’s the last umph of the hurricane that I considered increased by GW — that umph that breaks levees and flattens houses.

    Comment by Lynn Vincentnathan — 26 Apr 2006 @ 11:53 AM

  197. RE solutions, I’m hoping either for a plug-in hybrid or an electric car. EVs are a lot more simple than I.C.E. cars, & cheaper to run & maintain & fix & can run on alt energy. I think they’d be much cheaper to manufacture if done at same level of mass production. Now they have lithium ion batteries that give an EV a 300 miles range, and recharge 80% in 15 minutes (they’re expensive now, but could come down). And who wouldn’t want a snack break after driving 5-6 hours?

    Only problem is car companies are crushing EVs with a vengeance, I think bec the companies are tied into oil. See

    Comment by Lynn Vincentnathan — 26 Apr 2006 @ 12:05 PM

  198. RE: 182,

    Emanuel is saying in frequency too but only in North America.

    Comment by Mark A. York — 26 Apr 2006 @ 12:11 PM

  199. Re: 162

    My understanding of the power leakage issue is that it is mostly a wash in climates where indoor heating is used on a regular basis. The waste heat reduces your heating bill. OTOH, I can see that it is a big problem in Texas…

    Comment by Richard Wesley — 26 Apr 2006 @ 12:42 PM

  200. To add to what Don Baccus said in #194: Also, as the press release from Toyota on the second-generation Prius explains: “Besides achieving targets in the use and disposal stage, emissions of CO2 and other atmospheric pollutants have been reduced over the entire life cycle of the new Prius, including in the development stage.” (See )

    Comment by Joel Shore — 26 Apr 2006 @ 1:27 PM

  201. greetings from an admiring lurker; thanks for the information. My questions, the answers to which I may have missed in this string, are how can one relate the forcing at 2XCO2 to an expected atmospheric temperature rise in a way that a citizen can understand; and is the forcing as stated as a degree C to be compared with the forcing at 280 ppm (pre industrial) NOT with today’s measured temperature or rise above average? To put this another way, the forcing degrees measure something else than the reported increase in atmospheric temperature since pre-industrial times (which I believe from Hansen and others is .8 deg C), but what is the relationship stated for laymen? While I am at it, what is the beginning point in time for the .8 rise? Thanks. I think the IPCC did a disservice to themselves and us with the infamous range of temperatures for 2100, and it looks this time as if they are focusing on the 2x forcing plus more, but without a date attached.

    Many thanks to all.

    Gary Braasch

    [Response:Not quite sure what the question is. I think the best answer may be the “climate sensitivity”, which is the degree of warming expected (at equilibrium) when CO2 is doubled. The best answer to that is “about 3 oC” with a 95% confidence interval of about +/- 1.5 oC around that- William]

    Comment by Gary Braasch — 26 Apr 2006 @ 2:19 PM

  202. Response to Remark #137, where Maureen Vilar stated: “A small number of models showed a slight drop in temperatures, particularly in phase 2. Of course these models had to be excluded from the final study – they did not represent pre-industrial climate accurately!â??

    According to the Stainforth et al. article, they used a grand ensemble of 2017 unique simulations. Out of 2017 runs, 869 simulations were ruled out as â??unstableâ??, which is 43% of all runs. The 1148 remaining (allegedly stable) runs represented 414 different models. That leaves that each model was judged by only 3 initial conditions. Few remarks and questions are in order:

    1. What is the criterion for correct representation of pre-industrial climate? How valid is the assumption that if the CO2-induced radiative forcing is artificially kept constant, the climate would not slide into an ice-ball anyway?

    [Response: The GCMs are written to start off stable, with no change in forcing. A GCM that wandered off into an ice age of its own wouldn’t be representative of the current, or recent past, climate, and would be no use – William]

    2. Actual initial conditions for the problem consist of temperature field, pressure field, moisture field, high cloud field, etc etc. Formally speaking, every such field has infinite dimensionality. For the computerized model, each field has at least the dimensionality of the grid in use, times the range of amplitudes at each grid node. This amounts to quite substantial number of variants of initial conditions. One would think that the set of 3 initial conditions per model does not represent the spectrum of all possible initial conditions very well.

    [Response:The atmospheric initial conditions don’t matter a lot – the system loses memory of these quickly (we all know that weather isn’t predictable, yes?). The oceanic initial conditions matter rather more (but these are actually slab models, no?, so they don’t have a deep ocean) but are supposed to represent the pre-ind conditions. There is no intent in the project to explore sensitivity to initial conditions – William]

    3. The deviations into cooler side were explained by complex interaction between heat flux, moisture buildup, etc in some spots of the globe, so the cool spot members were excluded. However, those cases were taken from the fundamentally-same model topology. What kind of analysis was done to identify if some inversed condition would occur, so some hot spots would emerge instead of cold spots, especially given quite limited coverage in initial conditions?

    [Response:Less sure about this. One of the criticisms of the study has indeed been that many of the high-sensitivity models may well have been unrealistic; the criteria for checking were weak – William]

    4. If only 3 initial conditions were tried to judge stability or instability of each model member, how one can conclude that the remaining thousands of variants would lead to same results (given the fact in #3), so that a seemingly stable model is in fact unstable and must be excluded as well?

    I think it is enough to conclude that predictions of the paper have little grounds for any practical certainty.

    [Response:Given that the study produces a large range, you’re pushing at an open door – thats exactly what they are saying (that a high sensitivity may well be possible). Others (James Annan for example) would say that observational constraints mean that sensitivities about 4.5 oC are very unlikely – William]

    Comment by Alexi Tekhasski — 26 Apr 2006 @ 2:36 PM

  203. You guys did read everything I said about the prius. I did say in it’s FIRST iteration. The sencond set of cars is much more promising to me. (80/100MPG instead of 52MPG). And if you want to call it handwaving, then whatever, think of this, when the first hybrids came out (aka the prius) in 2003/2004 the MSRP for the prius was 22K versus a 13K corrolla. So you have to pay 9K more for a car that gets you 14 more MPG. Now I don’t know about you but even with today’s gas prices it is a little difficult to overcome that expense delta between the two. If you drive 200 miles a week, which takes 4 gallons of gas at $3. 52Weeks times 4 gallons times 3 dollars = $624 savings a year. It would require you to drive the car 10 years to get 2/3 of that savings back. If you double the mileage to 104MPG you still only save $1200!(What if you financed the car, then what?) How on earth do you think this is a feasible alternative? Whether or not the car costs more energy than it saves, (We have our differences in opinion, and quite frankly none of us are qualified to really argue about it one way or the other! Thus, if I am handwaving so are you unless you happen to work for toyota!) it simply is not a feasible option for 95% of the population that works hard for a living. When such options get similar in pricing you will see a higher uptake in interest from the everyday joe’s out there. Face it, until alternative energy cars can compete with similar classes of regular cars in price the mainstream public will not be very eager to buy them. (Either that or gas has to go up to 10 dollars a gallon.)

    Comment by James — 26 Apr 2006 @ 2:46 PM

  204. re: 204. The link to in post 201 regarding the new Prius and CO2 emissions in the development stage is not “hand-waving”.

    Comment by Dan — 26 Apr 2006 @ 2:56 PM

  205. 187 redux. Sorry Gavin, unless I am very much mistaken there are a lot of tropical cyclones that never make to hurricane status, pushing a reasonable percentage of them over the limit would make an observable difference.

    [Response: You are correct. But detectability is a function of the signal to noise ratio – a small shift in the mean of a distribution can give a detectable signal at the tail but not a significant signal near the middle. – gavin]

    Comment by Eli Rabett — 26 Apr 2006 @ 3:09 PM

  206. Some folks have responded to my questions about alternative energy and I would like to engage in a little rebuttal.
    I am only trying to raise the issues of practicality to some folks heads as they are not technically grounded. (It is like me telling the climatologist how to model wind, as such don’t tell an eletrical engineer how to generate power!)
    Alternative forms to me are still not ready for prime time usage. (I can be corrected but please only someone who has actually worked in the power industry please!)
    Wind Power. Great but the power density per square foot of ground used is abysmal at best. On top of that you say screw the birds! Sorry we have ceased a lot of activities due to wildlife destruction. I am not a bird lover by any means but it is still an issue. Second, wind power is not readily available everywhere you would want it and it is unpredictable so it is not a constant or dependable source. Third, say it is possible to provide all of our power needs from wind power. What would we do to the world ecology? How would the earth’s ecology react to the extraction of that much power? What if the cure is worse than the disease? (I do not know this,I am only thinking out load here. However it is a reasonable line of thought, as we still don’t “know” enough about GW even though it is happening right now. How would we know the affects of something we have not tried yet?)

    Hydro is not green at all. (Contrary to popular belief!) It requirese massive land-use change and environmental damage. It also tends to make the stored water’s release Methane and CO2 due to the extra biomass destroyed by the dam’s head of water.

    Nuclear to me is the best alternative we have. It is here, it is mature, and it has great power density. And it requires the least effort on our part to make it happen as no new technology has to be invented. (Even with all of the negatives it has with spent fuel storage and lifetime.)

    Solar is also getting to be a good alternative, however unpredictability, power density, and also power storage and transportaion are problems here. (Still to me it is the best of the “renewable” sources.) I have also heard several people say put those things in the desert. Sure no problem, ever heard of sand storms and what they do to optical surfaces? Further not every country has a desert so are you going to run power lines from the Sahara to Europe? Lastly what will the affects be to Earth’s climate with the addition of hundreds of thousands to millions of hectares worth of Solar panels are installed?
    All I am doing is trying to convey as sense of reality here. Saying that we can depend on emergent sources of energy now and in the near future is like jumping on thin ice looking for a fish.

    Geothermal. A great source, however the issue with it is its availability. It is simply not an option for large areas of the earth as the geothermal heat is too deep within the crust at those locations. Also again what happens to earth when we extract vast amounts of power from it on an every increasing basis?

    Comment by James — 26 Apr 2006 @ 3:15 PM

  207. Re 205,

    To me it is handwaving, that is marketing slide and has no more “proof” than my statements. If toyota would illustrate those claims, then I am all ears. Until then it is handwaving.


    Comment by James — 26 Apr 2006 @ 3:27 PM

  208. re 193.

    Lewis, I don’t know how to reply to the many important points which you brought up. I’ll just say, … awhile ago, I read discussions from early 20th century Weather Bureau climatological data summaries. There seemed to be an openness to share information for the good of all, great attention to detail, little regard for self pride and no heavy desire to make money regardless of that’s just business. Climatological data was free to anyone.

    Comment by pat neuman — 26 Apr 2006 @ 3:40 PM

  209. Re William’s Responses to 196 & 202:

    196) Yes I initially thought that (especially after Ray’s responses about how to cut emissions) it might be of use for a sub-section, but also thought of possibly a “spin-off” site and now think that maybe better for a separate one. However it was worth suggesting here as I’m sure there are quialified people who read this site. A sort of “RealSolutions” as someone suggested on another thread.

    202) I think (and I apologise if I have this wrong) that Gary’s asking for a translation of what the climate sensitivity means in “real terms” as in actual temperatures by specific dates. The problem with that of course is that the answer is “It depends…” (though some of the variables are referred to in his question).

    Comment by Adam — 26 Apr 2006 @ 4:02 PM

  210. Thanks for the reply, William, at 202:

    “…. I think the best answer may be the “climate sensitivity”, which is the degree of warming expected (at equilibrium) when CO2 is doubled. The best answer to that is “about 3 oC” with a 95% confidence interval of about +/- 1.5 oC around that…”

    Yes,that is the currently accepted figure for doubling CO2 equivalent — does that number refer to warming from now til then (I don’t think so) or from pre-industrial or above the 20th Century average? Can it be compared with the measured warming up until now (above the average) of .8 C? Can one say “expected atmospheric mean temperature when we reach doubled CO2 is about 3 degrees higher than __________.”? I am trying to find a way to talk about this that folks can understand, so it needs to be accurate and have a comparison or starting point. Thanks.

    Comment by Gary Braasch — 26 Apr 2006 @ 5:42 PM

  211. I can’t help but be impressed by how consistently the “godawful Metro” meme has been pushed by members of the cpdn team.

    In fact, the programme makers focussed exclusively on broadsheet coverage, quoting from (I believe) the Independent and Telegraph. This is the headline and first two sentences from Roger Highfield at the Telegraph:

    Screen saver weather trial predicts 10°C rise in British temperatures
    By Roger Highfield, Science Editor
    (Filed: 27/01/2005)

    Increased levels of greenhouse gases will have a much greater impact on climate change than previously thought and will lead to a “dramatically different” future, according to the largest ever climate change experiment.

    If the predicted levels of greenhouse gases predictions are reached, the ice caps are likely to have melted and Britain will be an average 10°C warmer.

    The Indy’s headline was “Global warming is twice as bad as previously thought”

    For readers from the outside of the UK, I think it’s fair to say that these papers are about as good as it gets, in terms of quality reporting.

    By all mean criticise the programme if you want, but criticise them for something they said, not something they didn’t say – especially as your criticism is mostly making claims of missed or misleading context!


    Comment by James Annan — 26 Apr 2006 @ 6:22 PM

  212. I am making just another attempt to find a layman’s explanation about what climate sensitivity numbers can mean about future world temperatures. In the initial post, Gavin wrote that the articles “…confused the notion of an equilibirum sensitivity with an actual prediction for 2100…” Did you actually propose a correct way to explain what it means, Gavin? In my last post (211) I posited a phrase “expected atmospheric mean temperature when we reach doubled CO2 is about 3 degrees higher than __________.” in order to find out if this is a correct way to say it and to fill in the blank with a comparison. As I mentioned before, journalists and the public are going to jump at the highest number of any range of sensitivity so it would be good to be able to give it the correct interpretation.

    A follow on question (a tad impolite) is, if the sensitivity number is not a guide to possible future temperatures, and therefor policy planning (like a threshhold of dangerous interference per UNFCCC),what is it good for?

    Respectfully (really)


    Comment by Gary Braasch — 26 Apr 2006 @ 10:15 PM

  213. Gary,

    The problems with associating sensitivity with a temperature in 2100 are twofold: first, at the time we reach CO2 doubling, the temperature will lag behind the equilibrium value due to thermal inertia, especially in the ocean (thought experiment – doubling CO2 today will not cause an instant 3C jump in temperatures, any more than turning your oven on heats it instantly to 450F), and secondly, the CO2 level we are at in 2100 depends on what we do between now and then anyway, and it may more than double, or not.

    Nevertheless, climate sensitivity is part of the puzzle, and it particularly matters if you are interested in stabilisation scenarios, since it indicates what a particular equilibrium CO2 level will mean for equilibrium climate. There is a good RC post on this here.

    Comment by James Annan — 26 Apr 2006 @ 10:55 PM

  214. Re #204 (james): You continue to slant your calculations against hybrids. It is simply not correct to compare the MSRP for a Prius and some base model Toyota Corolla. If you were to do that, why not ask why people pay much more for a Lexus than a Toyota Corolla (both non-hybrid models). You are comparing a car with much different features.

    When Consumer Reports did their comparison, they compared to the Corolla LE and got a price differential of $5700 (and this was even after taking into account the market reality that you could buy the Corolla for below the MSRP but would pay the MSRP for the Prius). On the Prius messageboard that I sometimes go to, people were arguing that this comparison was still unfair as the Corolla LE still is not equivalent in room or features to a Prius…But, it is at least a little bit more in the ballpark than your estimate!

    Of course, whether the Prius pays for itself in the current market uncorrected for externalities is a different question than whether it would pay for itself once you accounted for the price of gas if it included all the environmental costs and much of the cost of the Iraq War (which, even if not directly about oil, is really pretty much about oil in the sense that it is what makes that whole region of important strategic interest to us).

    Comment by Joel Shore — 26 Apr 2006 @ 11:03 PM

  215. Gary,

    On a larger level, it is common in science to break up a big problem into smaller problems. This is particularly important if this helps isolate very different aspects of the question. The whole problem of how much warming will occur convolves lots of questions involving how the climate reacts to greenhouse gases, the carbon cycle, and our future path as societies in terms of our energy use (and other emissions). It is useful to break these apart by asking a question specifically regarding the climate system: What is the climate’s sensitivity to a given change in CO2?

    One can then separately address the issue of what levels of CO2 we are likely to actually reach, a question that involves understanding the possible future course of society (complicated by the fact that our future course will be influenced by our understanding of this and other environmental problems!) and, to a lesser effect, some issues involving the carbon cycle such as how the ocean’s uptake of CO2 will evolve over time and to what extent melting in the polar regions will release additional CO2 (and methane) as they warm.

    Unfortunately, the general public and the media often don’t understand this division and end up muddling things together…thinking of the climate sensitivity number as predicting the actual warming. Fortunately, since a doubling of CO2 from pre-industrial levels by 2100 is at least in the ballpark of expectations, the error they introduce by doing this isn’t too huge. However, it is important to keep in mind that we might easily more than double it if we really don’t make much effort to cut back (I think the current estimated reserves of fossil fuels would increase CO2 by a factor of like 5 or 10, which would mean a warming of roughly 2-3 times the climate sensitivity for doubling CO2 [because of the logarithmic dependence of the resulting warming to CO2 levels])…and CO2 levels may be able to fall short of doubling if we really make a very strong effort to reduce emissions.

    Comment by Joel Shore — 26 Apr 2006 @ 11:20 PM

  216. Re: #213

    Gary, I think you’re looking for a simple layman’s explanation. I’ll try, but I’m not a climate scientist, so if I get it wrong, moderators please correct me.

    “Sensitivity” means the total equilibrium rise in temperature due to doubling CO2. That means that if we raise CO2 to double *pre-industrial* levels, then the expected equilibrium temperature increase will be about 3 deg.C above *pre-industrial* temperature. Doubling it again (4x pre-industrial) will raise another 3 deg.C, doubling yet again (8x pre-industrial) yet another 3 deg. C. That’s assuming that sensitivity is 3 deg.C.

    It’s quite correct that there’s a lot of thermal inertia in the system, so we won’t see all that increase right away. But, it’ll be *in store* for us. Anyone care to estimate the lag time for global temperature response? Also, we don’t know that the sensitivity is 3 deg.C; that’s kinda what the whole thread is about!

    Comment by Grant — 27 Apr 2006 @ 1:34 AM

  217. I have spent some time this morning reading this blog and the comments associated with it. I have to admit i only got to #57. But what seems the most pressing to me, are the effects, of even a 2C rise in global temperatures. Wouldn’t that bring about massive famine all around the equator and raise the ocean levels sufficiently to inundate many cities? It would probably have an extreme drying effect on many ecosystems thereby changing them significantly. It would surly dry out the already unthawed tundra in Siberia and Alaska, which would add a very significant methane load to the environment. And would likely dry forests to the extent that fires would be widespread and also release massive amounts of green house gases. It would probably make our whether more erratic and thereby make agriculture much more difficult. We are seeing a pretty substation effects by just a 1-11/2 degree of warming. If you want to alarm the puplic into action wouldn’t that be the place to start.

    Comment by david Iles — 27 Apr 2006 @ 9:44 AM

  218. Thanks for the explanations about 2xCO2 sensitivity. It is not a simple thing to explain, but the oven idea is good as is the general idea that by pointing out this relationship, you are encouraging people to consider if continuing to add CO2 and other GHGs is prudent or not. Since the post that James Annan referred to (31 Jan 2006 Can 2°C warming be avoided?) uses a cat in the oven analogy, and the real temperature at 2xCO2 will depend on whether people change their behavior in ways we really can’t predict from this viewpoint, then the cat in that oven must belong to Schrodinger. I prefer the frog in a pot analogy myself, if we must resort to torturing animals to make our points. Gary

    Comment by Gary Braasch — 27 Apr 2006 @ 1:06 PM

  219. Re #217: Time lag for global temperature response. I’m not a climatologist, but I’ve read 3 books on climatology. Looking at W.F. Ruddiman’s “Earth’s Climate: past and future” you will find his graphs of future global temperature response. As best I recall, it’ll take about 200 years to peak and about 2000 years to completely restabilize, returning to the usual state of quasi-equilibrium.

    Comment by David B. Benson — 27 Apr 2006 @ 1:19 PM

  220. Morgan, you’re demomstrating pre-technological thinking when you imagine that physics and chemistry and electronics can support human life without the rest of the environment. Look up ‘ecosystem services’ for references. Most of what’s being provided ‘free’ is from life on earth, starting with the oxygen in the atmosphere.

    Comment by Hank Roberts — 27 Apr 2006 @ 2:12 PM

  221. Re #220: “it’ll take about 200 years to peak and about 2000 years to completely restabilize, returning to the usual state of quasi-equilibrium.”

    Why do people assume that the “usual state” of climate system is “quasi-equilibrium”? One would submit that multitude of large de-glaciation swings followed by bumpy relaxation into ice ages rules this assumption completely out, unless you have a very special emphasis on “quasi”. One would think that these huge historical variations are rather signs of a system that is very far from equilibrium, in which case the usual “sensitivity” technique is not adequate and may be misleading.

    Comment by Alexi Tekhasski — 27 Apr 2006 @ 2:59 PM

  222. Alexi, maybe ‘quasi-equilibrium’ is the wrong term. How about ‘tracking orbital forcings’? The ice core records seem to me to be in good, although far from perfect, agreement with orbital forcings at the approximately 41,000 and 26,000 years quasi-cycles. The roughly 100,000 year scale interglacials remain a mystery, at least to me. In any case, all these time scales are much longer than the 2 to 20 centuries I mentioned.

    Have you read Ruddiman’s book? How about Oldfield’s?

    Comment by David B. Benson — 27 Apr 2006 @ 4:49 PM

  223. I think 2000 year predictions are pretty problematic. That said, I’ll make one. Soon we will have begun an irreversible melting of the Greenland icesheet and if that happens that will have very significant effects on the climate, well pretty much indefinately.

    Aslo, regarding climate sensitivity a very key thing to remember, especially if sensitivity turns out to be on the high side, is that the “final” equilibrium temperature (Alexi’s concerns about there being such a thing aside) calculated from climate sensitivity does not take into account carbon cycle feedbacks OR ice sheet changes.

    We lay people tend to thing 2x CO2 means doubled by us. Doubled by us may in fact result in more than doubled CO2.

    Comment by Coby — 27 Apr 2006 @ 5:20 PM

  224. David, re #222? “tracking orbital forcings”

    The theory of direct orbital forcing is obvously incorrect, since integral of insolation does not change for more than 0.1% during eccentiricity variations. More, there does not seem to be any fromally-identifiable cyclicity at all. For example, the following paper
    finds that deep-sea and ice core records are formally indistinguishable from stochastic data even if the data are artificially tuned to Milankovitch cycles.

    The other theories of “amplification” rely on some sort of near-unstable undelying system with rich potential for internal dynamics, which must be also far from equilibrium to swing that wide while being well-bounded at the same time.

    People ususlly argue that reality usually follow the simplest possible rule. They are right – self-sustained chaotic oscillations _are_ the simplest explanation of the observed facts, with maybe some inclusion of well-known effect of frequency sysncronization in non-autonomous systems.

    [Response: Saying “self-sustained chaotic oscillations” doesn’t really say anything. The key is in getting down the physics that would give you such “self-sustained chaotic oscillations.” There is actually a great deal of work that has been done on this subject, but you shouldn’t dismiss all the orbital forcing work without taking time to look at what has been done. There’s a great deal of it, which goes beyond your cavalier dismissal. For example, the high-frequency precessional signal is actually a very,very large forcing, peak to peak. There is a modulation of the envelope of this by the eccentricity cycle. What you need to get ice ages out of that is just a rectifier. That’s where your nonlinearities come in. If you think that there is a self-sustained ice-climate oscillator that works without that kind of excitiation, by all means write one down and go publish it. You’ll be famous. –raypierre]

    Comment by Alexi Tekhasski — 27 Apr 2006 @ 5:42 PM

  225. Coby and Alexi, I am going to offer a much simplier, highly studied, and reasonably well understood system only by way of analogy. Alexi needs to understand that this system is, in nontrivial detail, nonlinear. This system is the power grid. The system must continually be stablized to maintain 60 Hertz AC electricity and between 110 and 125 VAC. The power grid has essentially no internal storage capacity, being best thought of the method to move electrical power from the producers to the consumers. At each moment in time the electic power consumed is equal to that produced. This follows from Kirkhoff’s laws.

    The power system is always at some operating point, but this operating point is continually changing as demand changes. Demand changes on an hourly, daily and yearly basis. In response to this change, producers go on-line or off-line or vary the amount of power supplied.

    I suppose that Alexi, in looking at a graph of the power supplied versus time for the Western Power Grid, will see chaos. Others will see responses to needs, without necessarily fully understanding the changes in demand.

    Coby will see the change in operating point as a ‘significant effect’. For the power companies this is true. Some possible operating points are more efficient for some producers.

    Both Alexi and Coby will appreciate that the fundamental equations to be solved to determine the operating point for the next 15 minutes do not always have solutions.
    None at all. Power engineers have to live with this and attempt to make approximations and quick adjustments.

    The main point is that here is a system of power flows which ‘chaotically’ oscillates in rather poorly understood ways. Nonetheless, when was the last time you were without electric power for more than 2 hours?

    Only an analogy, but I hope it helps.

    Comment by David B. Benson — 27 Apr 2006 @ 7:12 PM

  226. Re 225.

    No not really. Yes the supply and demand of power are always changing but the basic operating prinicple of the system is well understood. IMHO that is not so with climate science. The overall science is not near as mature, and right now every answer they have raises more questions.

    Comment by James — 27 Apr 2006 @ 10:16 PM

  227. The electric power grid is one place US political deregulation fell flat on its face. Even before the predictable gaming of the payment system by marketers, it failed because politicians don’t understand physics and mandated a regulatory system that violated physical law. Nature responded accordingly.

    With new solar flare season coming on, the problems will be showing up again soon. Can we do better with climate?

    While this is a rather old cite, it’s one good place to start:

    “Experts widely agree that such failures of the power-transmission system are a nearly unavoidable product of a collision between the physics of the system and the economic rules that now regulate it.”

    Look ahead to the next generation of coal-fired electric power plants. Raypierre makes the case very clear in the current Chicago Int’l Law J. that closed system combustion with oxygen can avoid much of the externalization of costs built into current plants; I imagine it can even contain the uranium and thorium fallout from coal (which is worse than that from a properly operated fission plant).

    Can we do this sort of thing right?

    Comment by Hank Roberts — 28 Apr 2006 @ 12:42 AM

  228. Re #206 and “Geothermal. A great source, however the issue with it is its availability. It is simply not an option for large areas of the earth as the geothermal heat is too deep within the crust at those locations. Also again what happens to earth when we extract vast amounts of power from it on an every increasing basis?”

    1. The most commonly used type of geothermal generator relies on local sources. There is, however, something called “Hot Dry Rock Geothermal” which can be used nearly anywhere.

    2. Human power needs are orders of magnitude less than world geothermal flux.

    3. As I said before, all methods of generating energy have bad side effects, but they do not have EQUALLY bad side effects. Solar, wind, geothermal, ocean thermal and biomass seem to me to be relatively good sources, whereas fossil fuels and nuclear do not. Windmills may kill birds, but at least they don’t allow many critical masses of plutonium to mysteriously disappear from inventory.

    Comment by Barton Paul Levenson — 28 Apr 2006 @ 12:06 PM

  229. Re 206: Plenty of electrical enegineers on both sides of this issue. In terms of wind – it can provide at least 20% of grid without storage; that is also well documenedt. It can provide more with small amounts of storage – provide 2 hours of nameplate capacity which equals 6 hours of average output and wind can provide around half of consumption.

    In terms of problem that we can’t always generate what we need where we need it – that is what power lines are for. Italy is looking at importing power from North African desert, France is considering importanting hydroelectricity from the wetter parts of Africa. We do know how to move power long distances.

    In terms of greeness – Wind kills fewer birds than any other power measure. Put it this way; if wind were to provide 100% of U.S. electricity (not practical for stability reasons but assume it as a way of measuring consequences) it would kill around 1 million birds a year with 1980 technology, probably a lot less with today’s wind gernators. By contrast feral cats in the U.S. kill 100 million birds per year. Cell phone towers and tall building kill – I forget the number, but same number of zeros. Overall human activity kills at least half a million birds per year in the U.S.

    In terms of dams, I agree that dams are not ecologically sound. But the thing is we have to build them for other reasons besides power anyway – water supply and flood control. Incrementally, how many fewer dams would you build if all power came from other sources, so long as those needs remain?

    In terms of mirrors and such getting scratched – you put up covers during dust storms. We’ve managed to keep solar thermal plants operating since the the mid-80s in the Arizona desert. Maintenance is one of the reasons solar thermal is 11 cents per kWh without storage; not just capital costs (though those are high). Solar thermal O&M is higher than wind power (though still lower than fueled plants).

    Comment by Gar Lipow — 30 Apr 2006 @ 6:12 PM

  230. Good example here of how reading the actual article, vs. reading only the press release, informs comments

    Comment by Hank Roberts — 3 May 2006 @ 3:05 PM

  231. Response to 220. I think your conception of nature is too limited. There are at least two and probably many many more earthlike planets. Even relatively nearby in the milky way galaxy.

    Comment by Morgan — 3 May 2006 @ 4:15 PM

  232. >231– “There are at least two and probably many many more earthlike planets.”

    Morgan, would you provide a link to at least the press release, and if possible the journal article supporting this statement? I’d like to compare them and see if I understand them the same way you do.

    To elaborate on the link I posted — this is one of the editors of Reason Magazine, who has changed his mind about warming; the thread below his posting includes comments from some people who read only his posting, some who read the press release, and one or two who actually read the science on which he based his change of mind. Their responses are from all bases, some purely political/ideological, some thinking about the science.

    It’s a contemporary example of intellectual honesty at work — and I do mean work, thinking about science is hard for everyone, and thinking despite one’s political assumptions is harder yet.

    The thread is already a very good illustration of why reading beyond press releases is important for understanding.

    Comment by Hank Roberts — 3 May 2006 @ 4:47 PM

  233. Re #231: Morgan, I opine not. Have you read “Rare Earth”?

    Comment by David B. Benson — 3 May 2006 @ 4:52 PM

  234. ‘In terms of greeness – Wind kills fewer birds than any other power measure. Put it this way; if wind were to provide 100% of U.S. electricity (not practical for stability reasons but assume it as a way of measuring consequences) it would kill around 1 million birds a year with 1980 technology, probably a lot less with today’s wind gernators. By contrast feral cats in the U.S. kill 100 million birds per year.’

    I *hate* that comparison, even though the wind power people trumpet it constantly.

    For it presumes that killing a species at risk such as the golden eagle is equivalent to a cat killing a house sparrow.

    That argument could be used by the timber industry to justify liquidating the northern spotted owl. There are only a couple thousand breeding pair in the pacific northwest, say on the order of 10,000 individuals alive at any one point in time (numbers flucuate greatly both by year and season).

    So by that argument, the timber industry can say “killing 10,000 spotted owl is nothing, after all cats kill 100 million birds each and every year!”

    Good grief.

    Side note regarding Gary Braasch. He’s a REALLY GOOD photographer. Internationally renowned. Check it out.

    Note that one of his photos graced cover of the November 17, 2005 issue of Nature, the one that said “Climate Change” in impressively large type.

    OK, Gary, you’ve been outed :) Gotta boost the rep of a fellow Oregonian. Glad to see you’re reading Real Climate.

    Comment by Don Baccus — 3 May 2006 @ 5:03 PM

  235. “Response to 220. I think your conception of nature is too limited. There are at least two and probably many many more earthlike planets. Even relatively nearby in the milky way galaxy.”

    How is this going to help us in the next century or two?

    “relatively nearby” in relationship to what? Portions of the universe that are even more unreachable than planets in our galaxy? Boy, that’s useful.

    Comment by Don Baccus — 3 May 2006 @ 5:08 PM

  236. re: demonstrating the greenhouse effect using a ‘homemade’ glass box (comment #119 and responses)

    My organization, the Yale Project on Climate Change, is keenly interested in finding a model that can be used in classrooms to demonstrate the greenhouse effect (using physical objects, glass, metal, whatever – not a computer simulation). Can anyone point me to one?

    The comments in this thread suggest that such a model is not possible, although some surrogates are mentioned in comment #150.

    We hope to find something that will appear more literally, directly analogous to the greenhouse effect to lay audiences, say, at high-school level, than the experiments mentioned above. I stress the words “appear” and “lay audiences” in that sentence.

    For example, having water level in a bucket represent temperature works at a level of abstraction that my university teaching experience suggests is unlikely to be found in individuals without a college-level physical science background.

    I’m not yet convinced that such a model is a physical impossibility. It may require some highly creative and original thinking, and it may not be something that gets its creator published in Science, but I’m not ready to give up: the benefits of having something tangible to present to people would be enormous.

    Comment by Richard K — 3 May 2006 @ 10:00 PM

  237. Richard, several people have pointed out that the total amount of CO2 in the preindustrial atmosphere, if it were all at ground level, would be five feet deep. Double that and you’d get ten feet. Raypierre pointed out that a simple photoelectric cell sensitive to the long-wavelength infrared can be used to measure how much IR gets through a column of gas (attach the output to a voltmeter). An infrared camera would perhaps also work, if you get the right wavelengths.

    So you could take a five foot pipe and cover both ends with IR-transparent plastic, fill it with CO2, measure how much IR passes through it (maybe even using sunlight as your source, with an infrared filter). Then do the same with a ten foot pipe. Comparison would be, very roughly, the difference between preindustrial CO2 and 2x that.

    I’m making this up, but there seems serious interest in actually showing people the effect.

    Alternatively, can you get a sky map/photograph taken in the infrared from a satellite, and compare that to a sky map taken from the ground? Most of the far-red/infrared stars should look very different through the atmosphere, to the extent it doesn’t transmit those wavelengths.

    Maybe a simple ‘infrared security camera’ or even an infrared photoelectric security beam device, or an infrared TV remote control, would demonstrate the difference between 5 feet and 10 feet of CO2.

    [Response: The device I was talking about wasn’t quite a “simple photocell,” but was a low-tech pyranometer, with a linear response between infrared flux and current. We bought these for our global warming lab, and they’re used in many physics departments for experiments with blackbody radiation. I think they cost around $50 to $100, but it would be interesting to know if something could be hacked up from a cheap infrared detector of the sort used in remote control systems. It’s certainly true that you should be able to measure the difference in IR absorption between a 2m and 4m column of CO2 with such a device. HOWEVER, note that you won’t really be illustrating the greenhouse effect as it works on a planet, since that depends on the difference in temperature between the ground and the upper atmosphere. The outgoing longwave radiation is composed not just of the radiation that leaks through to the top from the warm lower layers, but also of the “cold” radiation emitted from the upper atmosphere. If you take a tube of CO2 at 300K, and you illuminate it with a 300K infrared source, you’lll still see 300K radiation coming out the end of the tube, no matter how much CO2 is in there. I guess if you have CO2 at room temperature (around 300K) and illuminate it with a really hot source (maybe 600K), you’d get some sense of the effect of the “hot” radiation going in one end being replaced by “cold” radiation coming out the other. You could also have a lot of fun squirting some methane or HFC’s into the tube to see what happens. Note that a 2m tube of CO2 at 1 atmosphere pressure will be somewhat more absorptive than the same amount of CO2 spread over the depth of the atmosphere, since high pressure increases absorption. –raypierre]

    Comment by Hank Roberts — 3 May 2006 @ 10:30 PM

  238. Re: #236

    Here’s an idea. I don’t know whether or not it’ll work.

    Start with a model “earth” — a thin, hollow sphere (so it takes very little energy to change its temperature). Paint it black.

    Enclose it in a glass sphere. Attach it by hanging it by a thread from the top of the enclosing sphere. Choose a thread with the lowest possible thermal conductivity, and make sure the model earth doesn’t touch the enclosing sphere. Pump all the air out of the enclosing sphere. This will reduce heat loss from conduction and convection.

    Enclose the “enclosing sphere” in a big glass box. Pump in a greenhouse gas. *Don’t* use CO2 — it’s not as effective a greenhouse gas as other choices. CH4 is 24x more effective (per molecule), CFCs are 10-20 thousand times more effective.


    Comment by Grant — 3 May 2006 @ 11:10 PM

  239. See 150 for Raypierre’s suggested demonstration.

    Comment by Hank Roberts — 3 May 2006 @ 11:35 PM

  240. “By a most unexpected technique — radio timing residuals — we have discovered two Earth-like planets around the pulsar B1257+12.”

    Carl Sagan

    Comment by Morgan — 4 May 2006 @ 12:42 AM

  241. Well, I think those are all good examples of press releases that require reading the whole press release, at least, to understand. The headlines say “Earthlike” and the text says this means “rocky, not a gas giant” — for example, 7.5x Earth’s mass, 200-400 degrees Centigrade is Earthlike. But not like Earth.

    Comment by Hank Roberts — 4 May 2006 @ 1:45 AM

  242. RE: 234. And if we were talking about continuing to kill raptors you would be justified. But the bird problem has been solved. We now know how to locate generators so they kill many fewer creatures and also locate them where they won’t kill raptors. Incidentally how does rebutting a common libel against wind make you a ‘wind person’. The Sierra Club, Greenpeace, NRDC and the Audobon society all support wind – including the wind farm off Cape Cod. Sounds like a pretty green power source to me.

    Comment by Gar Lipow — 4 May 2006 @ 2:09 AM

  243. re comment 236

    Richard, I’ve used the leaky bucket analogy in schools, and it generally seems to be understood – as long as they’re old enough to have covered the fact that pressure in a liquid increases with depth.
    There’s some other stuff on our website ( – teaching resources) in particular an experiment with a bottle of carbon dioxide (under key stage 3/4 science) which might be of interest.

    Comment by sylvia knight — 4 May 2006 @ 7:04 AM

  244. RE 242: “And if we were talking about continuing to kill raptors you would be justified. But the bird problem has been solved. We now know how to locate generators so they kill many fewer creatures and also locate them where they won’t kill raptors. Incidentally how does rebutting a common libel against wind make you a ‘wind person’. The Sierra Club, Greenpeace, NRDC and the Audobon society all support wind – including the wind farm off Cape Cod. Sounds like a pretty green power source to me.”

    If you read my earlier posts on wind power, you’ll learn that I support wind power and am aware that siting and turbine design issues have largely been solved.

    That doesn’t save the really, really stupid argument made by wind power advocates that “cats kill more birds than wind turbines”.

    That really is a timber industry-style argument you’ve got going there.

    Given the resistance some in the industry have had in the past towards implementing the monitoring and site evaluation protocols that lessen the impact, it’s a great way to trigger a knee-jerk “the industry’s full of it” reaction among those who are potential allies.

    If you’re comfortable with it, don’t complain when people react negatively to windfarm proposals.

    And, yes, I know the Audubon society supports wind power. I sat on the board of the 2nd largest chapter in the country for 15 years, after all.

    I also remember our being called “anti-environment” in the press by wind power advocates for demanding raptor surveys of a proposed windfarm site in the Columbia Gorge known to be frequently used by golden eagles (a species of concern) and peregrine falcons (listed).

    [Response: Okey doke; let’s agree that windpower is a good thing, generally, that it’s desirable that engineering solutions be sought to (further) minimize and certainly monitor the effect on bird life — especially raptors — and that the “cats kill more birds than wind turbines” argument isn’t a stellar example of a well-reasoned scientific argument addressing a legit scientific concern. Now let’s please move on from this. I note that a lot of the discussion here has moved away from the subject of press releases, but it’s been for the most part interesting and substantive, so I’m inclined to let it go on for a while longer before closing the comment form. –raypierre]

    Comment by Don Baccus — 4 May 2006 @ 10:37 AM

  245. Re 236, demonstrating the greenhouse effect:

    What if your tube of CO2 were divided by a piece of plastic into two sections – the “upper atmosphere” component and the “lower atmosphere” component, and the lower atmosphere segment were heated or the upper atmosphere segment cooled before shining an IR source vertically down the tube? The two sections are mixed afterward by removing the plastic and a temperature taken. Wuld this result in a GH effect due to more IR bouncing off the cooler “upper atmosphere”? The same process could then be repeated, with the same initial temperatures, for an air mixture containing less CO2. Would the resulting temperature inside the tube end up cooler?

    [Response: Not bouncing, not bouncing, please! Infrared doesn’t bounce off of CO2 in the usual gaseous greenhouse effect. Infrared is absorbed by CO2, and re-emitted at the temperature of the CO2 doing the absorbing. (There is an exotic scattering greenhouse effect that may work with dry ice clouds on ancient Mars, but that’s another matter, not related to global warming on Earth) But yes, if you could somehow maintain a temperature gradient in the tube it would be a bit like the actual greenhouse effect. Note that since you don’t have any significant compression effect in a short tube, you’d have to do the experiment “upside down,” i.e. with the cold CO2 at the bottom instead of at the top. Otherwise, the cold CO2 would just sink and mix with the hot CO2 at the bottom. –raypierre]

    Comment by Dan Allan — 4 May 2006 @ 1:34 PM

  246. This is getting informative!

    You could, perhaps, get a ‘compression effect’ — need a sanity check here, please — by spinning the tube (like a spoke on a wheel, attached at one end). Near the center it would have no added “weight” and as you move out toward the distal end each molecule would have more centrifugal ‘weight’ added, so be denser.

    Hmmm, how narrow a tube would you need to defeat rapid mixing by diffusion, if possible at all?

    Anyhow taking off on the prior suggestion of a membrane to set up:

    Put the cold gas toward the center, the hot gas toward the end, separated by a membrane; spin the thing up to where you have a density gradient from center to end (sufficient to hold the hot gas at the ‘heavy’ end?); remove the membrane (or would you even need to remove a membrane if it were transparent to IR?)

    Of course a centrifuge spinning a ten foot tube fast enough to make a density gradient in the contained gas would be a potential ballistic launcher in the the “kids, don’t try this at home” category.

    All in all Raypierre’s suggestion of doing the experiment ‘upside down’ makes more sense and would be a lot simpler, I think. Oh well.

    [Response: This has the makings of a cute exam problem. How fast a centrifuge would you need to make this work? As a rough estimate, let’s say we want a 10K temperature variation from the dry adiabatic lapse rate in a 2m column. The dry adiabatic lapse rate is g/cp, where g is the acceleration of gravity and cp is the specific heat at constant pressure. For CO2, that’s about 12K per kilometer for 1 Earth g. Therefore, to get the desired temperature variation over 2m, you’d need a centrifuge that got you up to about 500 Earth g’s. Don’t count on riding along in the thing while you’re making your infrared measurements! –raypierre]

    Comment by Hank Roberts — 4 May 2006 @ 4:06 PM

  247. >246 comment
    I know little laboratory desktop centrifuges reach 500g — a centrifuge 4 meters in diameter to produce 500 g at the rim? The flywheel energy storage people have the math for it:

    Comment by Hank Roberts — 4 May 2006 @ 6:12 PM

  248. A press release by the U.S. CCSP is at:

    In How not to write a press release, Gavin wrote:
    … the scientists also need to appreciate that most journalists will only read the press release, … This implies that the press release itself is the biggest determinant of quality of the press coverage …

    In the last day or two, comments (104, … 122, 128, 130, … ) have been posted at under RC .. A Mistake with Repercussions.

    I would like to see comment from others about the 02 May 2006 at

    Is that a good example of How, or how not, to write a press release?

    Comment by pat neuman — 4 May 2006 @ 9:59 PM

  249. Pat, about that press release:

    According to the published report, there is no longer a discrepancy in the rate of global average temperature increase for the surface compared with higher levels in the atmosphere. This discrepancy had previously been used to challenge the validity of climate models used to detect and attribute the causes of observed climate change. This is an important revision to and update of the conclusions of earlier reports from the U.S. National Research Council and the Intergovernmental Panel on Climate Change.

    I think this is a reasonable summary.

    Comment by llewelly — 4 May 2006 @ 10:40 PM

  250. >Okey doke; let’s agree that windpower is a good thing, generally, that it’s desirable that engineering solutions be sought to (further) minimize and certainly monitor the effect on bird life — especially raptors — and that the “cats kill more birds than wind turbines” argument isn’t a stellar example of a well-reasoned scientific argument addressing a legit scientific concern.

    This actually ties back to the question of press releases. To what extent is it reasonable to answer the question asked rather than try to read the questioners mind? Quite often people make the argument “wind kills birds”. The cat argument is a quite legit answer to that question. There are three reasons for phrasing the question this way – ignorance (in which case someone really believes that sheer number of birds is the problem and the cat comparison is reasonable), sloppy phrasing (in which case the cat comparison is a reasonable way to avoid the other person inadvertantly misleading readers) or deliberate dishonesty (in which case the cat comparison is again a legit way to prevent deliberate misleading). In short if you want the raptor issue dealt with bring up the raptor issue. If, inadvertantly or deliberately, somebody misleadingly implies that wind is a problem for sheer number of birds killed, then it is reasonable to put that number into perspective by comparing other things that kill much larger numbers of birds. In point of fact this sort of comparison is the only way to rebut that particular phrasing. If you don’t like cats, we can use cell phones, coal smokestack, tall buildings, agriculture, automobiles. But it is quite true that wind kills large number of birds; just many fewer than other things that kill large number of birds. If someone brings up birds in general, rather than raptors that is a reasonable way of to rebut them.

    This is likely to come up in global warming science as well. Sooner or later someone will do a study refuting a really dishonest or sloppy argument X. And global warming deniers will cry out at the attack on this weak sloppy argument; “how horrible; you are ignoring Y” they will cry. And the answer will be , I think , the same as I just made – if you want a reply to the stronger argument, make the stronger argument. If someone advances a sloppy argument then it needs to be rebutted to prevent it misleading others.

    I do think in the future I will also bring up raptors to keep it in perspective as in “no environmental group worries about sheer number of birds killed” followed by a comparison to put raw numbers into perspective “many do worry about poorly sited wind generators killing endangered birds, especially raptors” tell the story of Altamont farm and the proposed Exxon farm which was quite properly stopped. “However the modern wind industry knows how to avoid these problems so long as their feet are held to the fire to ensure they carry out mitigating measure such as proper location, proper siting, proper spacing, slow moving easily visible blades, towers that don’t make good nesting sites to attract birds and so on.” I think if you know an objection is a mistatement of another objection, it is still neccesary to rebut the mistatement, but then move on to the real argument and rebut it too.

    Don’t know whether this can carry forward to press releases for global warming studies. I suppose it can in the sense that you can say that “Study A fails to find any support for hypothesis X. It does not however deal with hypothesis Y which which Study B found no evidence for.”

    Comment by Gar Lipow — 4 May 2006 @ 11:43 PM

  251. The Catholic Archbishop of Sydney (Australia) has made a comment regarding global warming in a speech to US Catholic business leaders, Dr Pell said:

    “Western democracy was also suffering a crisis of confidence as evidenced by the decline in fertility rates. Pagan emptiness and Western fears of the uncontrollable forces of nature had contributed to hysteric and extreme claims about global warming.

    In the past, pagans sacrificed animals and even humans in vain attempts to placate capricious and cruel gods. Today they demand a reduction in carbon dioxide emissions.”

    Seems that he is at one with the editors of “First Things”

    Comment by Lawrence McLean — 5 May 2006 @ 8:43 AM

  252. Re: #150 … look, we’ve been asked to spike this issue, but statements like this can’t go unanswered…

    “There are three reasons for phrasing the question this way – ignorance, sloppy phrasing or deliberate dishonesty…If someone brings up birds in general, rather than raptors that is a reasonable way of to rebut them.”

    Your statement ignores the reality that the wind power industry first came up with the “cat kill more birds” line in response to concerns about raptor kills. Not windfarm kills of starlings or house sparrows (two species – both invasive pests – among those most frequently killed by cats). The line was come up with to belittle concerns about raptor kills, and to make those concerned about raptor kills look foolish in the eyes of the public and (more importantly) political and regulatory bodies.

    That line was used on conservation groups who were insisting on more comprehensive raptor surveys before approval of the Columbia Gorge windfarm I mentioned earlier. We were “anti-environment” for insisting on comprehensive surveys for
    windfarms which, even at their worst, don’t kill nearly as many birds as cats.

    Nevermind the fact that our concerns were focused on one species of concern (golden eagle) and one threatened species (peregrine).

    Wind power advocates can rationalize their efforts to alienate conservation biologists all they want. Apparently it is a technique that works well for the industry.

    I suggest we do as Ray asked – spike this conversation. After all, the only effect your posts have are to strengthen my somewhat negative opinion of the wind power industry and advocacy groups here in the US (as opposed to my attitude about wind power itself, which is positive).

    Comment by Don Baccus — 5 May 2006 @ 10:48 AM

  253. Llewelly,

    Thanks for your comment in 249 on if the U.S. Climate Change Science Program (CCSP) press release (link below) is an example about how to, or how not to, write a press release dealing with climate change.

    I take your comment as meaning you believe the press release is fine in not mentioning greenhouse gas emissions as the primary cause of global warming.

    My 30 Oct 2003 press release on climate and hydrologic change in the Upper Midwest cost me $500 and my career job of 29 years as a flood forecaster for NOAA NWS (I know that because my supervisor later told me that John Mahoney, NOAA Administrator and then director of the U.S. CSSP that he wanted me fired for doing the press release. Thus, that press release was a one time deal for me. Other scientists have more opportunities, possibly.

    Also, in 2003, AGW wasn’t as certain to many people like it is to many people now. I believed it was important then to make a connection between climate change in the Upper Midwest and AGW, and that rapid GW would have severe consequences. My position was and still is that this threat to the planet is unprecedented, and is from our actions in our burning fuels. As such, everything, including the way press releases are written, should be done not in any business as usual manner but in ways to help humans reduce their GHG emissions ASAP.

    U.S. CCSP press release, at:

    Comment by pat neuman — 5 May 2006 @ 11:02 AM

  254. Pat, you wrote:

    I take your comment as meaning you believe the press release is fine in not mentioning greenhouse gas emissions as the primary cause of global warming.

    That’s because I screwed up my comment and didn’t quote this part:

    The evidence continues to support a substantial human impact on global temperature increases. This should constitute a valuable source of information to policymakers.

    I apologize for the confusion.

    Comment by llewelly — 5 May 2006 @ 11:50 AM

  255. Llewelly, your comments are appreciated. My comment is I would like to see fuel emissions pointed to as driving global warming … in all U.S. press releases dealing with global warming.

    Comment by pat neuman — 5 May 2006 @ 9:52 PM

  256. Help,
    I think that I am correct in thinking that the temperature rise from 1910 to 1938 is generally thought to be from natural forcing. Whereas the later rise 1976 to 2005 is thought to be because of human influence (ie C02 etc) .

    I cannot help but wonder how it is that the two rises in temperature have the same amplitude of signal as shown in the CRU Global Hemisphere Temperature “Annual Global graph”

    This graph is base-lined 1960 – 1991 , from this graph it can be seen from 1910 to 1938 the temperature rose by 0.45ºC over 28 years and from 1976 to 2005 the temperature rose 0.48ºC over 29 years. Therefore if you divide the rise in temperature by the number of years you then have the amplitude of the signal, this would be 1910-1938 0.45 / 28 = 0.0161ºC per annum and 1976-2005 0.48 / 29 = 0.0165ºC per annum.

    It is very rare in my experience that two entirely different inputs result in the same amplitude of output signal, especially when the two inputs are so totally different. Also the two inputs are quite arbitrary in the way they operate, the natural input relying on factors such as the solar output the inclination of the planet etc. Whilst the human input relies on 4 to 5 Billion people doing what they wanted to do when they wanted to do it. You then throw in the odd economic down turn / upturn the odd war or two etc. There must surely be a pretty unrealistic chance that they would achieve exactly the same input into the system over the two 28/29 year periods.

    If you remove from the graph the years between 1938 and 1976 and put the graph back together you can see that the two parts of the temperature rise fit together perfectly (cut the graph where the 0 line breaks the two temperature lines)

    Is it not more likely that the two inputs are one and the same (whatever that is) and in fact we influenced the climate during the period between 1930 – 1976 by depressing the temperature rise that started in 1910 to 1938 and continued again in 1976?

    [Response: No. One clue you can see directly that these two events are not the same is the spatial pattern of temperature changes – they are significantly more uniform in the later period. Plus, we are all aware that there are many factors that influence the global mean temperature – not just CO2, but solar, volcanoes, aerosols, other GHGs, ozone etc… In the earlier period many of the them trended the same way (GHGs rising, solar increasing, volcanoes less common etc), in the later period, only GHGs are increasing. But more fundamentally, looking for single and exclusive factor explanations for any recent climate trends or changes is just too simple. – gavin]

    Comment by Barry Wells — 7 May 2006 @ 1:56 PM

  257. This graph is base-lined 1960 – 1991 , from this graph it can be seen from 1910 to 1938 the temperature rose by 0.45ºC over 28 years and from 1976 to 2005 the temperature rose 0.48ºC over 29 years. Therefore if you divide the rise in temperature by the number of years you then have the amplitude of the signal, this would be 1910-1938 0.45 / 28 = 0.0161ºC per annum and 1976-2005 0.48 / 29 = 0.0165ºC per annum.

    My numbers don’t agree with yours. I downloaded the CRU data, and for the global average, from 1910 to 1938 I get 0.0127 ºC/yr, while for the period 1976-2005 I get 0.0184 ºC/yr. Using just the northern hemisphere, I get 0.0160 ºC/yr from 1910-1938 and 0.0184ºC/yr from 1976-2005. This is from a trend analysis of the actual data.


    Comment by Grant — 7 May 2006 @ 6:48 PM

  258. I’m looking at the press report, but the press release must have been well done for this story. It’s specific and clear.

    Full story here:

    Beginning, excerpted:
    ” Ice-capped roof of world turns to desert
    “Scientists warn of ecological catastrophe across Asia as glaciers melt and continent’s great rivers dry up

    By Geoffrey Lean, Environment Editor
    Published: 07 May 2006

    “Global warming is rapidly melting the ice-bound roof of the world, and turning it into desert, leading scientists have revealed.

    “The Chinese Academy of Sciences – the country’s top scientific body – has announced that the glaciers of the Tibetan plateau are vanishing so fast that they will be reduced by 50 per cent every decade. Each year enough water permanently melts from them to fill the entire Yellow River.

    “They added that the vast environmental changes brought about by the process will increase droughts and sandstorms over the rest of the country, and devastate many of the world’s greatest rivers, in what experts warn will be an “ecological catastrophe”.

    “The plateau, says the academy, has a staggering 46,298 glaciers, covering almost 60,000 square miles. At an average height of 13,000 feet above sea level, they make up the largest area of ice outside the polar regions, nearly a sixth of the world’s total.

    “The glaciers have been receding over the past four decades, as the world has gradually warmed up, but the process has now accelerated alarmingly. Average temperatures in Tibet have risen by 2 degrees Fahrenheit over the past 20 years, causing the glaciers to shrink by 7 per cent a year, which means that they will halve every 10 years.

    “Prof Dong Guangrong, speaking for the academy – after a study analysing data from 680 weather stations scattered across the country – said that the rising temperatures would thaw out the tundra of the plateau, turning it into desert…..”

    Points to Dr. Lonnie Thompson for having gotten a core out of there. I wonder if there’s time for any more.

    Comment by Hank Roberts — 7 May 2006 @ 10:04 PM

Sorry, the comment form is closed at this time.

Close this window.

0.655 Powered by WordPress