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Groundhog day

Filed under: — gavin @ 7 June 2009

Alert readers will have noticed the fewer-than-normal postings over the last couple of weeks. This is related mostly to pressures associated with real work (remember that we do have day jobs). In my case, it is because of the preparations for the next IPCC assessment and the need for our group to have a functioning and reasonably realistic climate model with which to start the new round of simulations. These all need to be up and running very quickly if we are going to make the early 2010 deadlines.

But, to be frank, there has been another reason. When we started this blog, there was a lot of ground to cover – how climate models worked, the difference between short term noise and long term signal, how the carbon cycle worked, connections between climate change and air quality, aerosol effects, the relevance of paleo-climate, the nature of rapid climate change etc. These things were/are fun to talk about and it was/is easy for us to share our enthusiasm for the science and, more importantly, the scientific process.

However, recently there has been more of a sense that the issues being discussed (in the media or online) have a bit of a groundhog day quality to them. The same nonsense, the same logical fallacies, the same confusions – all seem to be endlessly repeated. The same strawmen are being constructed and demolished as if they were part of a make-work scheme for the building industry attached to the stimulus proposal. Indeed, the enthusiastic recycling of talking points long thought to have been dead and buried has been given a huge boost by the publication of a new book by Ian Plimer who seems to have been collecting them for years. Given the number of simply madeup ‘facts’ in that tome, one soon realises that the concept of an objective reality against which one should measure claims and judge arguments is not something that is universally shared. This is troubling – and although there is certainly a role for some to point out the incoherence of such arguments (which in that case Tim Lambert and Ian Enting are doing very well), it isn’t something that requires much in the way of physical understanding or scientific background. (As an aside this is a good video description of the now-classic Dunning and Kruger papers on how the people who are most wrong are the least able to perceive it).

The Onion had a great piece last week that encapsulates the trajectory of these discussions very well. This will of course be familiar to anyone who has followed a comment thread too far into the weeds, and is one of the main reasons why people with actual, constructive things to add to a discourse get discouraged from wading into wikipedia, blogs or the media. One has to hope that there is the possibility of progress before one engages.

However there is still cause to engage – not out of the hope that the people who make idiotic statements can be educated – but because bystanders deserve to know where better information can be found. Still, it can sometimes be hard to find the enthusiasm. A case in point is a 100+ comment thread criticising my recent book in which it was clear that not a single critic had read a word of it (you can find the thread easily enough if you need to – it’s too stupid to link to). Not only had no-one read it, none of the commenters even seemed to think they needed to – most found it easier to imagine what was contained within and criticise that instead. It is vaguely amusing in a somewhat uncomfortable way.

Communicating with people who won’t open the book, read the blog post or watch the program because they already ‘know’ what must be in it, is tough and probably not worth one’s time. But communication in general is worthwhile and finding ways to get even a few people to turn the page and allow themselves to be engaged by what is actually a fantastic human and scientific story, is something worth a lot of our time.

Along those lines, Randy Olson (a scientist-turned-filmmaker-and-author) has a new book coming out called “Don’t Be Such a Scientist: Talking Substance in an Age of Style” which could potentially be a useful addition to that discussion. There is a nice post over at Chris Mooney’s blog here, though read Bob Grumbine’s comments as well. (For those of you unfamiliar the Bob’s name, he was one of the stalwarts of the Usenet sci.environment discussions back in the ‘old’ days, along with Michael Tobis, Eli Rabett and our own William Connolley. He too has his own blog now).

All of this is really just an introduction to these questions: What is it that you feel needs more explaining? What interesting bits of the science would you like to know more about? Is there really anything new under the contrarian sun that needs addressing? Let us know in the comments and we’ll take a look. Thanks.

1,071 Responses to “Groundhog day”

  1. 1
    Joseph O'Sullivan says:

    I agree there is something of a groundhog quality.

    How about updating some old posts like the old ocean acidification one? New information can be posted without rehashing all of it.

    Maybe have some guest scientists with expertise in areas like general ecology, marine biology or some other life science write posts to explain some of the connections between climate and the biosphere.

  2. 2
    Mark says:

    Hang in there and keep communicating the facts. Repetition is a necessary part of the process especially when the deniers try so hard to confuse and complicate. It may seem like an uphill fight and maybe humanity cannot not be made to care enough to save themselves but at least you have to try. Keep up the good work

  3. 3
    Daniel says:

    Well the question that I always ask is not about the science, but about the solution. And those who propose nuclear seem to think that simply building lots and lots of nuclear reactors throughout the third world is going to solve everything. But they never explain how it would solve everything. Nor do they deal with the all too human problems which become exacerbated in regards to nuclear, propensities to militarism, to suspicion, to greed for power, corruption, incompetence, accidents. Not to mention ignoring the radiation and toxins released from mine tailings and waste rock, where the vast bulk of radiation is liberated.

    It would solve nothing.

    PS the “type the two words” test has just failed me three times. They are really hard to differentiate.

  4. 4
    Joel Shore says:


    I think I know what comment thread you are talking about in relation to your book and I agree with your assessment of those who were commenting on it. Having read only a small part of your book myself, I did make an attempt to defend it there. (And, I did very much enjoy the parts of your book that I did get to read so far, which are your introduction, Tim Hall’s chapter, and a smattering of other parts.)

    As for suggestions for future topics (and falling mostly under the “contrarian sun” part): One thing that I feel would be useful would be more discussion of the problems with the arguments being put forward mainly by Roy Spencer suggesting that a lot of the warming that we see could be due to internal variability in the climate system that leads to spontaneous changes in cloud cover and hence essentially cause changes in radiative forcing (which he then combines with his claim that the shortwave cloud feedback is strongly negative to argue that most of the warming we’ve seen is due to such spontaneous variability in clouds and not to greenhouse gases). I know you’ve already had a little bit on that here but more would be useful.

    And, more generally, some posts with more details about the modeling of clouds and where the models agree and disagree in terms of their cloud feedbacks would be good.

    Another topic, which admittedly might be one of limited interest but would certainly be interesting to me personally, would be some discussion of climate science as a career (and, for example, a career-change from other related fields such as physics).

  5. 5
    dhogaza says:

    I think you guys do a great job of bringing new research to the table, and can’t think of anything other than that to suggest.

    I found this interesting, though:

    the need for our group to have a functioning and reasonably realistic climate model with which to start the new round of simulations.

    I’m sure you’re talking about finishing the implementation and testing of incremental improvements, but what are they? New research results driving changes in the equations that form the physical model? Code efficiency improvements?

    Anything interesting to talk about there, or is the level of change too trivial to be interesting? I have no way to judge.

  6. 6
    MacDoc says:

    Perhaps focus on the unexpected or unexposed sources of climate altering emissions – ie shipping fuel efficient vehicles across the Pacific in container ships that are huge unregulated emitters.

    and look at the misconceptions about choices in strategy ( personal and policy ) as this article does well

    I do notice in some of the forums I participate in a distinct “quieting down” of many of the most irascible and loud denier voices in climate specific threads.

    I see little of that “volume decrease” in “letters to the editor” comments on something that mentions climate change. If anything it seems louder and less informed in those venues. Clearly there is little consensus onthe reality or the threat of climate change in the letter to the editor writing cadre and they seem to have found full voice in repeating discredited concepts.

  7. 7
    Mark A. York says:

    Refuting this kind of stuff is useful. I guess in some ways many have moved on to the impacts of AGW, buying the concept aside. It’s the same methodology and the same players: Roger Dodger to the rescue.

  8. 8

    As a non-climate scientist I agree with dhogaza (#5), that RealClimate does a great job of bringing new climate research to the table and those are the posts that would most like to see continue.

    For example, your February 2009 post on “Antarctic warming is robust” was really helpful for non-experts trying to understand the complex scientific issues surrounding climate change:

  9. 9
    Yvan Dutil says:

    I know how you feel. Climate change, darwinism, energy problem it is all the same fight. As I scientist, whatever the topic, we face the same challenge.

    It is only recentely, I have discovered why. The way science is taugh for most people is be memorizing standard recipes given by an authority. This is true even for people who are suposingly scientists. I have seen this attitude in engineer and chemist too. Unless, you are train to be a resercher, you will almost never experience the difficulties and complexities of science. Simple scientific paper can have 10-20 concepts that are presupose to be true. In the real world, there is almost nobody working on such complex topic. Therefore most people will tend to think this is a complex story making, which as little relation to reality.

    In these conditions, if you have two “equivalent” experts, you choose the story you like to most. Scientists doing research are making something like 0,1% of the population, and this is probably an overestimate by a factor 10. In consequence, dont expert this situation will change soon.

  10. 10
    smile4me2day says:

    There are lots of questions worth exploring! One I’d like to see is a thread on that free EdGCM climate model from Columbia and how best to use it.

    It looks like a very cool and fun program, but like anything, having a little inside info from the experts always helps make it more successful in the hands of newbies.

  11. 11

    The high walls between science and politics may be impassible.

    There are no similar arguments about other controversial sciences like dark energy, black holes and cold fusion – because their economic impact is not destructive and in any case would be very slight (for now).

    Clearly, political and commercial interests prefer to fit and shape information in ways to preserve and enhance revenue. It gets contentious as these interests continue to brace against the political and economic changes that are obvious in addressing the problem.

    We face a test of civilization itself, whether we can meet and understand the laws of physics, or temporarily ignore them.

    Thank RC for all that you do.

  12. 12
    Dean says:

    It was interesting to see your comment about the sci.environment glory days as I was a regular participant in that.

    Here are some issues that I think would be good for you to address:
    1. The tipping point. I’m not aware that the IPCC report deals with the issue of when positive feedbacks become so bad that cutting our emissions will not help. Hansen has been very public on this, and it would be good to get a summary of how much we know about this.
    2. Your thoughts on a National Climate Service – what should it do, how can it help.
    3. Add a section/link somewhere that lists new and quality online resources – whether reports or studies, etc – as they become available (and which are aimed at a general audience), maybe with a brief comment on what is new about them if it isn’t obvious.

    Also – just finishing The Long Thaw (there wasn’t a waiting list for it at my library :(. Good to see people talking about the longer term.

  13. 13
    Martin Hedberg says:

    Thank you for your great work.

    Geopolitical consequences of adaptation to climate change (global change) as well as mitigation and negotiations related to climate change may not be you primary subject. But at the same time not all of the people working with geopolitics, strategies etc are enough educated in climate science. Can you help overlap the gap?

    /Martin Hedberg

  14. 14
    susann says:

    I agree that the “Groundhog Day” quality of the debates are extremely tiresome. Disheartening. After I heard them all for the nth time, I decided to avoid all such debates. Not that I have all the answers, but that I’ve heard all the objections by the denialosphere and I feel that reading further repetition will achieve nothing except raise my BP.

    This blog should continue its very important work of bringing new research to the table, explaining it for the public’s consumption and clarifying any mistakes made by honest (and otherwise) critics and naysayers. I need to know why someone is wrong or right and I need someone with credentials to help me understand.

    Keep up the great work!

  15. 15
    Steve Fish says:


    We have heard some hints that predictions by climate scientists may be on the conservative side. Whether this is the case, or not, I would like to hear more about the factors and feedbacks that, by their nature, could cause significant deviations in predictions. Also, what are the feedback mechanisms, not included in climate models, that have the potential to impact our future.


  16. 16
    Arthur Smith says:

    Add another vote along with dhogaza (5) and Chris McGrath (8) – I’d love to see you talk more about your own research when you can. Going public about stuff too soon, about things which aren’t yet solid, can risk misunderstanding and misinterpretation, it’s true. But with some care I think it can be done in a manner that doesn’t leave false impressions, and the back and forth in comments can be edifying to both sides in case of confusion. Hopefully there’s enough background material on the site already that a few references are enough introduction, but if not that might also suggest some good new background topics to cover.

  17. 17
    Mike says:

    How about revisiting old posts and explaining why the predictions did or didn’t happen.

  18. 18
    Joe Hunkins says:

    Model falsifiability & verifiable experiments about CO2 effects.

  19. 19

    Gavin, I’m halfway through the book now and it’s excellent.

    Was happy to see he chapter by Kim Cobb, I had the chance to interview her last fall for a piece we aired on that ridiculous “Oregon” petition.

    IMHO RC is at it’s best when you write on new papers being published with your perspectives.

    As for the quality of the comments, you have no obligation to give a voice to the “breathlessly ignorant” (see C.P.). Certainly, spending time moderating is not high on your list of pleasant chores, but leave those comments for those sites that cater to those who you will never succeed in educating.

    The public IS “getting it”. I frequently mention climate sci. during weather casts, and I get very few responses from the “hoax” crowd. The true disbelievers are really few in number.

    The confused crowd is growing larger, and that’s the group where you can make a difference. I hear “I’m confused” a lot more than “it’s a hoax!”.

    How about some more on tropopause/stratospheric changes. New paper here looks interesting:

  20. 20
    EL says:


    I’m going to sound like an English professor here, but what audience are you trying to target? Are you attempting to target mathematicians, computer scientists, physicists, biologist, engineers, or general population?

  21. 21
    andre says:

    Thanks for a very informative web site and all the hard work which you and your colleagues have put into it. Some possible questions I would be interested in,
    – What steps are taken or experiments which are planned for validation and verification of the computer models?
    – What type of runtime is required for a typical model run (machine,number processors, options which eat up cpu time?). Can physically reasonable simulations be done with a desktop processor and with which codes?
    – Has the high profile nature of climate science affected anything at the paper or conference level compared to other sciences? Also, has it affected your everyday work environment in any way?
    – If you track page hits, what are some of the most popular articles on realclimate? (“The CO2 problem in six easy steps” and “What Angstrom didn’t know” are my favorites)

  22. 22
    Steve Chamberlain says:

    Gavin, thanks for this, it often seems as though there is an unlimited supply of bloggers, “journalists” (if I can use that term in this context) and authors who constantly do the “rinse and repeat” cycle with their “informed debate” and “honest scepticism”.

    One small nitpick – the author’s name in your OP should be Ian PLImer, not PILmer. I wouldn’t normally care, but the odds are someone will come along and try to make the case that mis-spelling his name means ALL facts produced on RC are wrong and thus AGW is bunk/ a Marxist plot/ the IPCC believe in fairies at the bottom of the garden/ Al Gore is fat.

    reCaptcha: “society trounces” Fill in the missing word…

    [Response: Fixed – thanks. -gavin]

  23. 23
    Craig Allen says:

    Perhaps you should refocus toward RealClimate more toward the science.

    Switch off the commenting a day or two after you make posts in order to save the moderation load for starters.

    Eskew commenting on manufactured controversies unless there is some relevant new research to report.

    And let us know more of what is going on in the field. There must be dozens of papers published each week that we hear nothing of. How about inviting reputable climate scientists to publish summaries of their work, and to do the moderation of their posts themselves.

    Cheers and well done so far.

  24. 24
    MacDoc says:

    # 7 impacts.

    Yes I find the impact aspect is more front and centre in online conversations….and some deniers are now touting – well warmer = good and it’s really all quite benign.

    One area I would like to see extended or emphasized is the role the cryosphere plays in damping extremes and how the loss of glaciers will impact Europe and other food producing regions in the mid latitudes.
    I find there is little ( and that included me initially )- sense of how big and influential the cryosphere is.

    There is much focus on the poles, Greenland and Antarctica but less so – in my reading – in the mid latitudes.
    Yet the glacial loss in the mid latitudes will have – is having – a more immediate impact on nearby populations – food, recreation and’ I would imagine, on the biota in the watershed below the glaciers.

    When you get an article stating Glacier National Park needs a new name since there will be no glaciers…..that’s very Real….pardon the pun to many people compared to some large chunks of Greenland or an Antarctic ice shelf MIA.

    Maybe poking into the impacts from a science standpoint that are very immediate and visible would bring the a needed flashlight into the murky corners of what is going on.

    Perhaps an added category of Impact of Climate Change might be useful on the right hand list.

  25. 25
    James Martin says:

    I read today a claim that in the paper published recently by Dr Steig et al. in Nature regarding the Antarctic warming trend, there is a weighting problem. They claim that most of the weighting comes from the peninsula stations, which represents a relatively small part of the continent.

    I was wondering if this is in fact the case? It doesn’t seem likely, but could you comment on this at all? If these assertions are left unchecked, before you know it they’ll be taken as fact.

    [Response: The point of the Steig et al paper was to use spatial correlations in recent data to look at how under-sampled parts of the continent likely changed over longer time periods. Those correlations will necessarily weight different stations differently as based on the physical characteristics. The analysis you saw is simply a fishing expedition, an analysis of what the calculation is doing (fair enough), combined with an insinuation that the answer is somehow abnormal or suspicious (not ok). But how is this to be judged? What would be normal? No-one there can say and they would prefer simply to let people jump to conclusions. It’s kinda of typical of their tactics, but not a serious scientific point. – gavin]

  26. 26
    Steve Reynolds says:

    I’d like to see something on what possible pitfalls exist in equating solar and GHG forcing, and on whether climate sensitivity should be the same for each of those forcings.

  27. 27
    Earl Killian says:

    You wrote, “Is there really anything new under the contrarian sun that needs addressing?

    I prefer RealClimate to concentrate on the open issues in our understanding of climate systems and promoting rational discussion between scientists and the reality-based community, and less on debunking the loonies.

    For example, I would like to know your opinion of which seems to raise an important point. If we shut down coal power plants and thereby eliminate aerosols that are keeping things cool, won’t we make exacerbate positive feedbacks such as permafrost methane? Do we need an aerosol substitute without the CO2?

  28. 28
    paulina says:

    I think it would be interesting to understand more about how communication works among different kinds/types of researchers engaged on a particular project.

    Maybe you could share some examples of relevant interdisciplinary challenges and triumphs?

    What divides, if any, have there been for y’all to bridge, how did you make that happen? Important steps along the way? Current challenges in this department?

  29. 29
    Chris Colose says:

    Hi Gavin,

    First of all, I have to extend thanks for everything that you and RC has done over the years. Always keep in mind when you are frustrated that there are many people who get good information from this site and appreciate the RC efforts.

    At this point in the game, my impression from reading various online sources is that there are now many “educated laypeople” who can correspond with skeptics (of all sorts) and dissect “new and improved arguments.” There was probably a time where many of us needed RC or a similar site to post “rebuttals” to every new argument, or even arguments that were phrased a bit differently than normal, but I no longer think this is necessary.

    It may be worth pointing out exactly what a non-expert would have gotten out of the RC effort if this site was the only thing they read for the last several years that relates to climate change. That person would understand the basic mechanisms behind how climate change works and would be able to communicate this to a lay audience. They would be able to answer general questions or arguments raised from such an audience. That person would be able to follow essentially all of the qualitative details in the literature (generally the introduction, conclusion, etc) of a review paper, and thus take away the important elements of that piece, perhaps only needing to jump over the statistical details or other technical aspects. That person would understand the basic timeline of how climate has evolved in the past, the basic mechanisms of how climate has changed, and what is important for it changing in the future.

    To this end, you have successfully created a person who can correspond well and at an “above wikipedia” detail, can answer criticisms, and can pick up further information on their own without getting tricked by common talking points. For what it is worth, I am only an undergraduate, yet have picked up enough background to maintain a website, work with Eli and others on submitting a paper to the International Journal of Modern Physics (possibly to end up in arxiv), and have given oral presentations on climate change physics aat an undergraduate conferences…much of this developing background I have picked up from RC or papers/other references that RC made me aware of. I would like to think that I have a slight advantage (at least to the extent of being able to follow the terminology and basic science) as I get an atmospheric science degree and prepare for graduate school, with this site being responsible for much of that development, especially in the earlier stages of my interest in climate.

    So what can RC provide in the future? As I’ve said, I no longer feel the necessity to respond to the “Christopher Moncktons” or “Inhofes” of the world, as if they had something important to say. Rather, discussing the latest details of peer-reviewed documents (and even trying to promote more guest posts from experts in their area), and perhaps the occasional technical post (that means maths!) would be great to read. Keeping up with what is going on at the year 2009, such as status reports on the AR5 or video links to recent cliamte conferences may be better than a refresher course in how the greenhouse effect works or why “CO2 lags temperature” does not disprove physics. It’s my experience that posts of high academic level also serve as a filter, already weeding out the people who just want to repeat something from a wingnut site, preventing them from posting in high amounts…probably because those kind of posts offer little opportunity to re-hash common talking points. Hope that helps


  30. 30
    Mark A. York says:

    I should take this time to say that I couldn’t have written my novel Warm Front, without Realclimate. I dedicated the book to RC. It’s not sold yet but I’m getting closer. The excellent scientific explanations of the workings of AGW were tantamount in the plot. The same ones Crichton ignored.

    RE:#24 I had a whole chapter on Glacier Park but had to cut it. The book features Alaska, Greenland, Antarctica, Boulder, Colorado and Washington DC. Salud!

  31. 31
    Ron Eades says:

    Gavin, don’t give up! Your subject is extremely complex and difficult for even an attentive mind to grasp if that mind has not been trained in any scientific field. And, there are a lot of us.

    Joseph O’Sullivan, comment one, has a good idea about updating, although you and the other scientists writing information for the rest of us probably have very little time for such an endeavor. As an generalized example of this need, the first time I discovered your website, March 2009, one of the first articles I read was dated several years ago and may have been partially superseded by information in David Archer’s latest book.

    In an ever changing world, people who are unwilling or unable to live in that world comfortably will seek certainty. The only thing obvious in global climate change is that it is exceedingly complex, and does change as new data is added to models (making those seeking certainty very uncomfortable). This turns those folks toward others (contrarians) who deny climate change. Contrarians seem to have the tendency to resist the reality of change and seek the status quo of a more simple world. Rather like the ostrich who can’t see problems and denies his rear is on fire. If goes away, the contrarians win a large battle.

    Other folks are simply innundated with the pro and con arguments and will not even discuss the issues. Some are just fatalistic about our chances for survival and have given up. Knowing some facts about climate change, about politicians who can be bought by oil and coal, can lead people into total dispair.

    Perhaps a RealClimate department of psychological persuasion, sans science words, submitting many articles to People magazine and other popular magazines would help to predispose non scientists to accept the reality of global climate change and the necessity to alter our way of impacting the environment. Convincing Oprah and then wrangling an invitation to the Oprah show would probably do more than anything else to convince people of the reality of global climate change. Would put pressure on politicians too.

  32. 32

    RealClimate, I’m amazed at your stamina so far. Congratulations. Having to teach the same things over and over seems like a good reason to not be a teacher. I’m so tired of saying the same things over and over as well, including that the educational system should at least teach everybody what science is. I have tried to involve myself with the local school board to try to remedy this. Reference: “Science and Immortality” by Charles B. Paul 1980 University of California Press. In this book on the Elegies of the Paris Academy of Sciences (1699-1791) page 99 says: “Science is not so much a natural as a moral philosophy”. [That means drylabbing [fudging data] will get you fired.]
    Page 106 says: “Nature isn’t just the final authority, Nature is the Only authority.”
    Every grade of K-12 and at least the first 2 years of college should require laboratory courses and Charles B. Paul’s book should be quoted often.

    As they say, the day we named ourselves Homo “SAPIENS,” Hugh Bris was in town. As far as arguments about evolution are concerned, for example, I structure the situation so that I evade the argument part and tell the opponent to go read some book or other. When somebody asks: “Where is the missing link?” I say: “You’re looking at him, and so am I.” The really bad news is that if global warming makes us extinct, the scientists go extinct along with all the rest. That is the ultimate argument in favor of a self-sustaining colony of scientists on Mars. I see no other possible way for a truly sapient race to evolve.

    The questions are begged: “Does this species really deserve to evade extinction?” and “Will a sapient species ever evolve in this universe, or are all candidates doomed to exterminate themselves by global warming?”

    My advice to RealClimate is:
    1. Keep plugging away because if you give up, the denialists will declare victory.
    2. The answers are rooted in the evolution of the human mind. Study sociobiology, psychology and psychiatry in your “spare” time. There are people who are, for the first time in history, attempting to address this problem.
    3. Hope that some medium-sized climate catastrophe will convince a majority of voters before our extinction becomes inevitable.

  33. 33 provides a service of immeasurable value. When fallacies are repeated in the media, there needs to be excellent sites like this where people can find solid ground.

    Gavin, your article states: “What is it that you feel needs more explaining? What interesting bits of the science would you like to know more about?” The offer is appreciated!

    Something has been on my mind for more than a year. As much as I believe I understand the subject, I am not a scientist and it would be of great benefit to learn how scientists look at the issue. That is, I am writing about the question of what concentration of atmospheric CO2 can be considered safe.

    Although the UNFCCC has no specified target for the atmospheric stabilization of any greenhouse gas (the UNFCCC Secretariat confirmed my hunch about this in an email of April 2008), the EU has a policy of avoiding 450 ppm which is often associated with avoiding 2°C of warming since pre-industrial times. These “avoidance” targets are based on scientists’ “reasons for concern” that global warming of more than 2-3°C may be dangerous. Last year, Hansen et al published different conclusions based on paleoclimate evidence and observations of ongoing climate change. That is, they are saying that atmospheric CO2 must be reduced from current “danger zone” levels of >385 ppm to a minimum of 350 ppm, and likely below that. My subjective sense is that the most talked about target of ‘avoiding 450′ continues to be the prevailing policy position, even among IPCC scientists. (With respect to the position of scientists and the IPCC, this is admittedly a supposition based more on scientist’ lack of comment on 350, and not based a lot of scientists speaking out in favour of the ‘avoiding 450’ target.)

    Could “avoid 2°C” and “avoid 450 ppm” be charactarized as a “soft” (or somewhat subjective) facts / targets that are based on a mixture of policy and a “reason for concern” among scientists? (If there is a main source that would explain the science and reasons behind the “reasons for concern” it would be of great interest. Might the reasons for concern be based on paleoclimate evidence and ongoing climate change (or something of equal or greater reliability?) On the other hand, to what extent can the Hansen et al conclusion (that CO2 needs to quickly return to 350 and problably lower) be accepted as a “hard” objective fact? Is there an alternate study or conclusion that is more robust or based on better data?

    Given that atmospheric CO2 will soon be exactly between 450 and 350 (i.e. at roughly the same time as when the arctic sea is predicted to start being ice free in summer–for the first time since before the dawn of human civilization) is “avoid 450” or “350 or less” the safest according to the best available evidence and the best available science?

  34. 34

    3 Daniel: You are simply wrong. I am curious about your fear. What exactly is it that scares you about nuclear power?
    Please read: “Power to Save the World; The Truth About Nuclear Energy” by Gwyneth Cravens, 2007 Finally a truthful book about nuclear power. Gwyneth Cravens is a former anti-nuclear activist.

    [Response: Please do not post under multiple names – I have edited the comment accordingly. – gavin]

  35. 35
    Fern says:

    As a reasonably intelligent non-science person who is following this whole issue closely, I find your posts extremely informative. As soon as a claim is made that AGW is bunk, this is my first stop. I think I’ve got a pretty good grip on the basic science, but I want to be kept up to speed by people I can trust. That’s you. Don’t stop. I feel very strongly that we all need to be scientifically literate, at least at a level that we can make responsible choices in our daily lives that (at best) improve the situation and (at least) don’t make it worse.

    So I would say, you’ve done a brilliant job of making the science accessible. Please continaue to dissect the disinformation and lay it all out clearly for us “lay-folk”.


  36. 36
    Lynn Vincentnathan says:

    I don’t even bother with the contrarians anymore. You could just have some standard rebuttals all set up in a very short post that briefly states their preposterous claim, then says, “For rebuttals look here, here, here, here, here, here, here, and here.” Then just delete the “heres” that don’t apply.

    What I want to see is discussion on the other end of the spectrum, such as discussion about (permanent) runaway warming, which scientists and others here had been telling me was impossible in this global warming era (I was actually only interested in temporary runaway, or hysteresis, as during the end-Permian), but recently Jim Hansen gave a presentation at the American Geophysical Union ( ) that talks of the possibility of runaway.

    So I’d like to see discussions about:
    1. possibility of climate hysteresis (as during the end-Permian)
    2. runaway (and the various poinst Hansen raised about this era being different from the past)
    3. the effects of climate change (e.g., human deaths) — which are in scientific fashion being grossly underestimated, I’m sure. Perhaps some guest commentators can participate.

    In other words skip the environmental “right” and take on the environmental “left.” That where the discussion should be — like whether or not runaway is possible, not whether or not global warming is happening, or whether or not it will have negative consequences.

  37. 37
    Thomas says:

    I thought of a few potential topics that might be of interest. In no particular order:

    >Geoengineering, with can mainly be split into two types, Short wave interventions, increasing the planets albedo, and long wave interventions -absorb/sequester greenhouse gases. The later can be thought of two diferent types, organic absorbers, and inorganic absorbers. What are the potentials -and drawbacks of the various proposals?

    > The Dim Young Sun problem: Theories of stellar evolution make it challenging to propose that the early earth was not frozen. What are the most recnt thoughts about this?

    > Century scale feedbacks: CO2 and methane releases as a result of climate change. What do we know about the potential for positive (or negative) feedback mechanisms? How much should we worry about these?

    > Ice Sheet Stability: What is the timescale of deglaciation? There are plausable mechanisms that may cause an assymetry of timescale bnetween glaciation and deglaciation. What are the current scientific best guesses as to how fats deglaciation can happen?

  38. 38
    Donald Oats says:

    Actually, it is worse than Groundhog Day, at least here in Australia. One of our independent politicians went across to USA last week, to check out the Heartland Institute’s “conference”. Today our national paper has him spouting “it is the sun”. Sheesh.

    On a more positive note though, I think that where RealClimate has been at its best as a blog, is in providing an entry point into current scientific literature. Something else that comes across is the manner in which science progresses – it seems that an awfully large chunk of the population have no idea at all, beyond some superficial characterisation of scientific method.

    Finally, I have purchased and am in the middle of reading several books on the topic of climate, which I mention for the hell of it. My own personal rating 0-5 ‘*’, more the better, and ‘-‘ means negative:
    [-*oooo] Ian Plimer’s rather tragic disjointed opinionated book (I am far enough into it to mightily annoyed at the cul-de-sacs and wilfully ignorant use of references to imply a quite different thing to the original authors’ conclusions). Even the major historical characters, such as Guy Callendar, are mis-spelt repeatedly, such is the meticulous attention to detail.
    [***oo] Chris Mooney’s “The Republican War on Science” spells out in detail the industry dirty tricks used to buy time for as long as they can get away with it. One interesting factoid is that once upon a time there were Republicans that saw environmental issues as terribly important – for example, Russell Train (Ch 3). If I were a conservative, I would not want corruption of science for political reasons, or any other reason for that matter. I hope at least a few people on the right (as well as the left) of politics read this and appreciate the damage being done by political shenanigans of this sort.
    [***oo] William J. Burroughs “Climate Change in Prehistory”, in which the interaction of climate and early humans is detailed. The enormity of even some fairly recent swings in the climate is deftly covered. Given the choice b/n Plimer and Burroughs, I’d go for Burroughs as far more reliable (dare I say ‘credible’) and intrinsically interesting.
    [****o] Barry Saltzman’s “Dynamical Paleoclimatology” is a good introduction into how mathematics, physics and the various components that make up climate, may be drawn together into a simplified global climate model. Undergrad to graduate level, as far as the maths goes.
    [****o] Gavin Schmidt and Joshua Wolfe’s “Climate Change” – great pix throughout, and the accompanying text is at a level that any interested reader should be able to handle. No maths as far as I can recall.

  39. 39
    Robin Johnson says:

    First of all. I would like the THANK RealClimate for their efforts. I am now much better armed to work against the denialists and their ‘victims’ plus just understanding things better (such as I can).

    Second, I’d like to point out a couple of things about human behavior that not everyone seems to understand that bears strongly on this type of dialog. What I’m about to say is purely anecdotal based on many years of personal experience, observation and experimentation on unwitting subjects.

    Since most people cannot judge the ‘truth’ of certain types of information for themselves, they rely on the source and/or how the information would fit into their world view instead of reviewing the ‘evidence’ and reaching their own conclusion.

    1. Information provided by an untrusted source that is contrary to someone’s world view is easily rejected as untrue.
    2. Information provide by a trusted source that fits into someone’s world view is easily accepted as true.
    3. Information provided by an untrusted source that fits into someone’s world view is often viewed as particularly true since even the untrustworthy say its true
    4. Information provided by a trusted source that is contrary to someone’s world view causes significant retrospection that usually results in the placement of the trusted source into the untrusted bucket – at least on that subject matter – but occasionally causes the someone to adjust their world view.
    5. Information provided by neutral sources (neither trusted nor untrusted) is simply viewed by its fit to someone’s world view.

    But here’s the REALLY odd bit, most people don’t REMEMBER the source of information after a relatively short passage of time. This means they really don’t know whether or not it came from a trusted or untrusted source. And so unless the remembered information has been strongly noted as untruth in their memory or their world view, people seem to make the weird assumption that the information is probably true since they bothered to remember it at all. Worse, once a person believes something is true, they will assume that the information came from a trusted source since they know they should only believe trusted sources.

    Obviously, disinformation campaigns clearly are built on some form of this ‘theory of mind’. One of the ways to discredit information is to claim that a piece of information came from a discredited source. The best way to discredit a source is to claim that an obviously untrue or suspect piece of information came from said source (regardless of reality).

    Disinformers also work hard at providing people with ‘information’ from neutral or trusted sources. So, when their ‘trusted’ news source reports ‘both sides’ without one or both being noted as clearly untrue – bizarrely the disinformation may get stuck into someone’s mind as having come FROM the trusted source. This is also the notion behind benignly or Orwellian named ‘education’ organizations spewing out well-phrased nonsense. The information seems like its coming from a trusted source. This also can have the effect of making trusted sources get confused with untrusted sources and making people think that ALL media is untrustworthy…

    Amusingly, this can work to the advantage of the scientist/educator. During a ‘friendly’ discussion or argument, the goal should not be to ‘win’ the argument on points but instead to provide as much accurate information in a non-threatening (hence non-sourced) manner as possible and always end the discussion in a friendly fashion. The information will often stick in the minds of all observers who will then forget where it came from and so it can often end up in their memories as ‘true’ information. Over time this can influence world views. Once a world view has changed, it becomes highly resistant to disinformation that contradicts that world view. This would be the goal of education (done right).

    I think its important to keep these things in mind particularly when engaged with ‘lay’ people. In other words, don’t expect non-scientists to think like scientists – you will be sorely disappointed.

  40. 40
    barry says:

    Having followed ‘skeptical’ thread evolutions and occasionally rolled around in the weeds myself, it’s not simply that a talking point is resurrected holus bolus. Often enough the same talking point comes with a slightly new focus. Sometimes I wish to post here to ask for another perspective, but refrain because the conversation is a few levels higher than I feel I can interrupt.

    Here’s one example:

    CO2 lag: If CO2 is largely responsible for the warming in deglaciation periods, why does the lag occur also for glaciation? Checking here, I see Cuffey and Vimeux referenced – that there is no lag when the planet cools down. But reading recent studies, that seems more like an outlier than central view. In the skeptiverse, the supposed lead of orbital variations for deglaciation and glaciation makes the idea of a primary importance for CO2 untenable. For me, if there is a lag during glaciation, I’d like to know why, and what resolution there is on the other feedbacks (aside from ice dynamics).

    I spend pretty much all my time posting simply laying out the mainstream view (as I understand it). Backing that up with accessible studies isn’t easy (but I’ve become pretty good at finding online versions in strange places). I don’t bother trying to convince anyone of anything – how could I take myself seriously, having no scientific qualifications?

    But I can grasp concepts pretty well, and I understand the importance of context. Mostly what I’m doing is unlacing mischaracterisations, correcting erroenous suppositions and pointing out errors of logic.

    I attended a climate change forum at the Sydney Opera House yesterday. The convener held it in the midst of a music arts festival and invited artists because he wanted to explore the notion of a new, inspiring myth – rather than the narrative of warnings – that would create a civilizational change. I sat there with the voices of skeptics in my mind and thought that, for those people, there would be no difference between myth and propaganda.

    As usual, I wondered if I wasn’t wasting my time with the entrenched in the blogosphere. Maybe it’s time to engage the apathetic.

    recaptcha says: ‘their gridlock’

  41. 41
    cce says:

    I’d like to echo those who’d like to know what’s going into the new round of models.

  42. 42
    Tim L says:

    Looking forward to this! thank you

    “”the need for our group to have a “functioning” and reasonably “realistic climate model” with which to start the new round of simulations.””

  43. 43
    taust says:

    Remember you have done a very good job. I who draws the conclusion that adaptation to the politically inevitable is a more useful option than mitigation appreciate the solid science of ‘realclimate’.

    On new topics how about

    a series identifying and discussing those topics where the research is most active

    a discussion on which are the highest sensitive parameters of the models and how well understood these factors are (may be same as above but I do not know enough).

    Thanks for the site.

  44. 44
    ScaredAmoeba says:

    Re Daniel #3

    OT but apposite to Solutions

    Not all nuclear reactors are created equal. I suspect that you are primarily thinking of conventional generation III – thermal reactors. These are not the only possible type.

    Please have a look at, where Barry Brook has been running an interesting series of posts about generation IV Integrated Fast Reactors – IFRs,

    IFRs have numerous advantages over conventional reactors. And yes a very few IFRs exist

    Much increase efficiency 95 vs 5%
    Fuels that require only limited on-site processing, meaning diversion for weapons applications requires additional dedicated facilities that would be unequivocally military.
    No additional Uranium mining – it could stop
    Safer design they shut-down
    Can ‘burn’ existing waste stockpiles, make electricity and produces only a fraction of the waste that lasts only ~500 y vs almost for ever.

    It’s hard to see a low carbon future without nuclear and IFRs would certainly look to be a vital part of the solution.

    Captcha inflate Hansen!

  45. 45
    Mike Coombes says:

    Since you asked, I do have a few questions that I don’t think have been addressed. I am puzzled about “natural variation” and haven’t really seen it quantified. It seems to be an explanation anyone can use to explain anything. I think natural variation should probably be split into two types. One would be the background variation one sees if the only changes in forcing were the daily and yearly variation in the solar heating of the earth. The second type would be variations due to frequency and size of volcanoes, or sunspots, and so on.

    So my first question is, if one runs a large global climate model for a century or two with constant CO2, what kind of variation does it produce and is it consistent with what we see for the earth if we remove the long term warming? How likely is a 5, 10, or 15 year warming, cooling, or flat trend in global temperature and other parameters for such a model? I assume someone has done this because there is an IPCC graph showing temperature versus time with and without CO2 changes.

    My second question is that I am surprised that the daily and yearly variation in solar heating of the earth can produce cycles much longer than a year. I would have assumed ocean thermal inertia would tend to dampen variation. What am I missing? Is it deep ocean circulation?

    Thanks for the great articles.

  46. 46
    ScaredAmoeba says:

    Once again many thanks to the RC team for your hard work. Please keep it up.

    As I watched the D-K video, I was immediately reminded of the incredibly asinine twaddle I have encountered on various blogs and in face to face conversations.

    Using the John Mashey scale of climate knowledge which places himself at 2 and a working climatologist at 10; I rate myself at ~0.

    Heaven only knows what score these self-deluded D-K exemplars would actually achieve, but it seems perfectly likely they would rate themselves 9-10, with climatologists presumably scoring 6-7.

  47. 47
    Lynn Vincentnathan says:

    RE #44, from what I understand the scientists do take into account the natural variations, incl seasonal, volcanic, el nino/la nina, and orbit-tilt stuff.

    That’s their null hypothesis — climate response to the natural stuff — and IFF natural stuff can’t explain the changes in climate that we are beginning to see, then they consider it might be the increased greenhouse gases. I think it’s more a model fit thing — they make models based on all the knowledge they have, such as physics AND whatever has happened in the past re the climate and GHGs (the natural stuff, and now the increased GHGs), tweak the models with best knowledge (like some volcanic eruption effect) to fit what is going on now, then shoot them ahead into the future.

    But I’m thinking if they shoot the models too far into the future, we may be talking infinite do-loops, and off the chart stuff. They’d have to take into account all the extra greenhouse gases that nature would emit as the world warms — from melting permafrost & ocean methane hydrates (and from recent studies we’ve been grossly underestimating the GHG potential from these) — and the positive feedback from reduced albedo. Tho eventually all of these “natural” sources which we have caused, like poking some sleeping dragon, would be used up.

    So the final question is, would it be climate hysteresis in which, say, only 90% of life on earth dies and eventually we get back to a life-hospitable climate, or runaway warming as on Venus, in which all life on earth dies.

    In a way we have been running an experiment for thousands of years, keeping greenhouse gases constant; and now we’ve shifted to the “let’s add a bunch of GHGs to the atmosphere and see what happens” experiment.

    I hope there will be some scientists (assuming future folks exist and have the wherewithal to teach science), or at least a few barbarian contrarians to see what eventually happens over the next 1000 or so years with this new experiment of ours.

  48. 48
    Randy Olson says:

    Gavin – Interesting that you mention all the people who commented on your book without having read it, then point readers to Bob Grumbine’s lengthy comments on my book which hasn’t even been published. He critiques the book as though he already knows what to expect from the voice of a scientist-turned-filmmaker. The only problem is there’s never before been a tenured scientist who has changed professions, gone all the way through film school and a two year acting class at age 38, ended up with a movie on Showtime, then written a book about what he’s learned. Until then, there’s really no data set upon which to draw any predictions of what to expect. It could be the ramblings of a madman who has lived in Hollywood for too many years, or it could be a useful contribution. We won’t know until mid-August when Island Press unleashed it on the public.

    [Response: I read Bob’s points as being about communicating to scientists in general – something he knows a lot about – and I mentioned his comment in order to spark engagement, not antipathy. I, for one, am looking forward to seeing your book when it comes out. – gavin]

    [Response: thanks for stopping by Randy. re Gavin’s last point, that makes two of us. I expect the book will become required reading (along w/ Chris and Sheril’s “Unscientific America”). -mike]

    [Further response: Randy emailed me to make it clear that the tone of what he intended didn’t quite come through on this comment. Just another example of how difficult this whole ‘communication’ thing is ;) …. – gavin]

  49. 49
    Anna says:

    Well if you are working on IPCC stuff … do you think its possible to monitor global emission of greenhouse gases in a way that would suit LULUCF accounting for UNFCCC ?

  50. 50
    donald moore says:

    I have information from a 1960s caxton encyclopedia stating that the icecap in antarctica being 2 mls thick compresses the landmass by a thousand feet.Since ice melts from the bottom to top will this not mean that as the ice melts this compressed land will spring back.Could this cause an increase in earthquakes?