Swindled!

All the previous parts of the programme were leading up to “so if it isn’t CO2, what is it?” to which their answer is “solar”. The section was curiously weak, and largely lead by pictures of people on beaches. It was somewhat surprising that they didn’t feature Svensmark at all; other stuff we’ve commented on before. Note that the graph they used as “proof” of the excellent solar-T connection turns out to have some problems: see figure 1c of Damon and Laut.

Along the way the programme ticked off most of the other obligatory skeptic talking points: even down to Medieval English vineyards and that old favourite, volcanoes emitting more CO2 than humans.

It ended with politics, with a segment blaming the lack of African development on the environmental movement. We don’t want to get into the politics, but should point out what the programme didn’t: that Kyoto exempts developing nations.

[Also: other discussion at InTheGreen, Stoat, The Guardian and

Media lens.]

[Update: What Martin Durkin really thinks!]

[Update for our german readers: A german version of the “swindle” film was shown on June 11 on German TV (RTL); here is a german commentary by stefan.]

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558 comments on this post.
  1. Nick Riley:

    They also stated that volcanic emissions of CO2 far exceeded those from human activity. This is untrue. Annual emissions from volcanoes are only 1% of the amount emitted to the atmosphere by humans.

    Hards Vicky L. (2005). Volcanic contributions to the global carbon cycle. British
    Geological Survey Occasional Publication no. 10, 26 pp.

    A free download on this is at http://tinyurl.com/lmd36w
    {originally http://www.bgs.ac.uk/programmes/landres/segs/downloads/VolcanicContributions.pdf }

    The programme also used the link between the ocean and the atmosphere and CO2.

    It was an inconvenient truth though not to also include in this description the fact that with business as usual CO2 emissions our oceans will acidify.

    see http://www.royalsoc.ac.uk/document.asp?id=3249

    Reason enough to urgently curb CO2 emissions- regardless of whether or not there is an anthropogenic factor in the current warming world.

    The programme was irresponsible and lacked a basic duty of care to the audience- and it now appears to some who appeared on the programme itself.

  2. Andrew Simmons:

    I’m delighted to see this swift response on RC – thanks!

    I got so annoyed with Channel 4 that I actually emailed them a complaint, which I’ve never done before. I’m sure that polite, articulate responses to the broadcast would be well received; C4 do generally seem to try to be responsive to viewer complaints.

    Their contact form is accessible from here:
    http://help.channel4.com/tv/contact/

  3. Sam Green:

    What I find so depressing is that both sides of this debate are as bad as each other. For Gods sake we might have a problem here, so lets debate like adults, something devoid from real science, climate audit and Durkin. Stop being so petty and lets act like scientists are supposed to do – debate.

    It is so depressing, as essentially I agree with real climate, but you do your self no favours. Your stance preaches to the converted, but if you want the masses you need to change your focus.

  4. Ron Taylor:

    #3 – Sam, the point you miss is that these issues have been debated, again, and again, and again… In science, that is done through the peer reviewed literature, not through the mass media. When you cannot win the debate in the normal process, then take to the media. Though not a climate scientist, I am frankly sick of reading that T leads CO2, as though that is the end of the discussion. Have these people never heard of strongly coupled variables? Feedback is real. When it happens, the physics of the problem says that increasing CO2 will increase T. Applying the equations through the models describes the observed temperature trends. Does this have to go on until our great-grandchildren are left with no hope?

    It is especially annoying to see people attack AGW folk in the guise of defending the future of the developing world. Just who do you think is going to suffer most under the BAU scenario? Do you think Americans will accept massive tax increases to help the developing world adapt? Okay, this is not part of the science, but skeptics have raised it, even though the downside risk for the developing world is far greater (in my opinion) under BAU.

  5. pete best:

    Its amazing that you guys manage to keep on top of the UK climate change mass media as well as your own US situation.

    Well done, keep it up

  6. Charles Muller:

    “The correct interpretation of this is well known: that there is a T-CO2 feedback”

    Hum… from what I read, I’d say there’s first an astronomic solar forcing (orbital/ regional, not TSI except for eccentricity cycle), and then diverse feedbacks including ice, CO2, vegetation, dust… and T of course. Your “T-CO2″ feedback is quite restrictive. For Al Gore, OK (climate science from ex-president) ; but we’re on RC (climate science from climate scientist), so you should be more careful with vulgarized explanations. Unless you consider ice/vegetation/dust and other poorly constrained feedbacks or circulation changes as negligible, of course.

  7. rick hanheide:

    I just read the Damon and Laut paper. Their most striking claim is that the key part of the graphs of Friis-Christensen and Lassen showing a strong link between solar and climate are the result of “trivial arithmetic errors”. As a non scientist, I’m thrilled. Seems like on this topic, at least, we ought to be able to come to a conclusion that everyone agrees on. So, in the 2.5 years since Damon and Laut published, what has happened ? Did Friis-Christensen and Lassen own up to their error ? Do they still maintain that they are right ? If all you guys with PHD’s can’t get to the bottom of “trivial arithmetic errors” in 2.5 years, the planet is in trouble from more than AGW !

  8. P. Lewis:

    I purposely didn’t watch “it”. This was partly because, like that reporter chappy over at the Guardian, I didn’t want to feel like I had to put by boot through the screen, but mostly because I’d never got around to watching Master and Commander before last night, and there it was on Film 4. Wonderful scheduling that, C4!

    I did catch 2 minutes of “it” in one ad break, when they were “talking around” the satellite and sonde data mismatch. Well, if that was an exemplar of the level of disinformation being imparted, then I’m glad I missed the other 97% of it and all its probable vaingloriousness.

    One thing that has intrigued me since is the world temperature plot they attributed to NASA, which can now be seen at various places (like at Stoat). They have a manilla(ish) shaded portion called “Post War Economic Boom”, which, fair enough, starts in 1945 and goes to about 1978/1979. So why do they have two labels, one saying “1940” which is pointing to about 1945 and one saying “1975” pointing to about 1980? And another point. Why is the “Post War Economic Boom” given to end in 1979? My recollection of events was that the Western world was thrown into recession (and some regions of stagflation) from about 1970, helped along in no uncertain terms by the 1973 oil crisis. So what were they trying to convey? The 70s were not a period of economic boom anywhere on the planet! Anyway, that’s a diversion into politics and economics, which is for another place, perhaps.

    I was further intrigued by that small upward blip in that “shaded” temperature downturn in that world temperature plot. “Seems” significantly above the long-term trend. So I got to wondering what could have caused it. I have a theory. The peak of this blip looks as if it’s the summer of ’66. Why of course … it’s all that hot air in the press in the lead up to the ’66 footie World Cup in good ol’ Blighty, culminating in all those kettles going on and the ensuing mega CO2 output required to meet the electrical load when Hurst’s hat-trick goal went in. Of course, if the 1940 and 1975 labels are to be believed, then my 1966 is in fact 1961, and that shoots my theory down in flames.

    Daft hypothesis? Why yes, and as daft as the C4 programme it would seem! Yes, I’m glad I watched Master and Commander. There certainly seemed as if there was more science in that with their sojourn around the Galapagos Islands than there might have been in that main-channel C4 “science” programme. Hollywood for science, now there’s a first. Al Gore gets an Oscar; Durkin gets a Golden Raspberry. (Mind you, I’ve seen neither in their entirety. So, have I got those awards the right way around?)

  9. P. Lewis:

    Re #7 and arithmetic errors.

    I believe degrees for radians usage has led some astray, too.

  10. Jim Prall:

    I too left a comment on the Channel 4 website (based on transcript excerpts and web coverage, as we don’t get this channel here in Canada), and based on the rogues gallery of contrarians they used.
    I’ve looked at some blog responses to the show that have built up already (my goodness they accumulate fast, with so many unwashed masses allowed to express their views freely :-) ) At first I was depressed over this: yet another tin of red herrings to rebut! But then I remembered that I’m not alone, and plenty of sensible people are helping out. I googled the show title, and came upon this blog repsonse:
    http://portal.campaigncc.org/node/1820
    which has already summed up a lot of good rejoinders to the show.
    As for “dT causes d[CO2]”, we can stress the basic physics behind the opposite direction. Skeptics love to quibble about attribution of recent dT, but the key issue for AGW is that basic physics tells us CO2 at current concentrations definitely does absorb IR. This is quantifiable, laboratory tested fact. The finer points are working out what the climate sensitivity is; here there’s some range in expert estimates, but it can’t be zero, as hard-core skeptics regularly imply. Even Lindzen admits it’s non-zero.
    So many skeptic sites are filled with “intuitive” arguments to the effect that CO2 can’t possibly have any effect, or that its spectral range is already saturated (no), or that [CO2] was much higher hundreds of millions of years ago (so!?), {insert red herring here}
    Anyway thanks to all RC contributors for carrying the ball.

  11. llewelly:

    Its amazing that you guys manage to keep on top of the UK climate change mass media as well as your own US situation.

    I thought William lived and worked in the UK? And comparing with Stoat, this appears to be mostly his work. (Of the other RC folks not in on this particular piece, I thought Rasmus lived in Norway, and Rahmstorf in Potsdam.)

  12. Al Bedo:

    “The troposphere should warm faster than the sfc”

    I didn’t see the program in question, but of course the NASA GISS model for one, indicates a large maxima of warming centered on the tropics around 300mb.

    This maxima is not observed in the RSS MSU, nor in the UAH MSU, nor in the RATPAC Raob set over the the MSU era.

    Clearly this model is not verifying this feature.

    [Response: Over the period when there are satellite measurements the model simulations span the response seen in the data. Thus there is no obvious contradiction between the models and the data. To be sure, stronger signals are seen for longer periods and for larger forcings, but you can only compare current observations with similar period transient runs. See the CCSP report for more details. -gavin]

  13. Chuck Booth:

    Re #3 You seem to be confusing the comments posted by RC readers, most of whom are not climate scientists, with scientific discussions that go on in university laboratories and seminar rooms, scientific conferences, and peer-reviewed journals. The debates that go on in the comments to the RC threads have no bearing whatsoever on the scientific issues of AGW and what can be done about it, except that some of us come away with a better understanding of the issues.
    I’m curious – in what way should the climatologists change their focus? They conduct their research, they publish their findings in peer-reviewed journals, they respond to requests for comments from journalists writing stories on AGW, they appear in TV documentaries on AGW, and sometimes they publish papers on AGW for the general public in non-specialist journals. What else should they be doing?

  14. George Marshall:

    Distortions are hardly suprising. This programme was not a scientific documentary in any normal sense: it was a piece of political polemic.

    The writer and presenter of the programme was Martin Durkin who is closely affiliated with the Revolutionary Communist Party which has a strong ideological opposition to environmental science. In 1997 Channel Four was forced to issue its first ever broadcast apology over extreme editing distortions in a similar series knocking environmentalism. It is a great shame that Carl Wunsch and the other legitimate scientists in the programme did not do a quick web search on Durkin before agreeing to contribute

    There was only one scientific advisor on the programme, Martin Livermore, whose sole scientific qualification is that he is the Director of a web-based think tank, The Scientific Alliance. The Alliance was set up by in 2001 by Robert Durward, the fiercely anti-green director of the British Aggregates Association, and Foresight Communications, a Westminster public relations and lobbying company, to “counter scare-mongering by the so-called green lobby”. The Scientific Alliance has no affiliation with any recognised scientific body but, like most of the contributors to the programme, it does have very strong links with the US public relations and lobbying organisations that have been so effective in setting the Bush agenda on climate change.

    Many of the people who appeared on the programme were captioned to institutions and universities that they left years ago in order to pursue their political campaigning work: Fred Singer, Patrick Michaels, Philip Stott and Tim Ball are among them. Richard Lindzen is a practising scientist, but a highly politicised and criticised one. All of them have close associations with the Washington public relations and lobby groups that front for the fossil fuel companies and the libertarian right (whose ideology is often strangely indistinguishable from the Revolutionary Communists. Strange things happen at the political extremes).

    Is it any surprise then, that these “scientists” were so persuasive. Most of the people on the programme are professional communicators who are more familiar with the chat show than the lab. Of course they give good interviews – it is what they do for a living.

    And let us not forget that they are effective because they have a very willing audience. We would all like to believe them. Wouldn’t it be wonderful to believe that the science is unsettled, that all that carbon dioxide that we are pumping into the atmosphere really has no effect, and that we do not have to worry about the future.

    I believe it is crucial that Wunsch, other distorted contributors and the scientific community as a whole puts in a formal complaint to the Channel Four and the Independent Television Commission. Please don’t leave it to the NGOs to stand up for your science.

    This is an except from a longer analysis of the track record and associations of the contributors to this programme on http://www.climatedenial.org Please visit the site and contribute to the growing discussion.

  15. BarbieDoll Moment:

    RE: 13

    …”The debates that go on in the comments to the RC threads have no bearing whatsoever on the scientific issues of AGW and what can be done about it, except that some of us come away with a better understanding of the issues.”…

    Scientific issues are not even the issue. Real people have significantly more power than any scientists due to their ability to capture the attention of the congressmen/women who can indeed, change or enact legislation that WOULD effect a change.

    Whether it be climate change, pharm, or online predators, the people with the power are you and I.

    And ultimately, at the end of the day, ones view on the matter of climate change, hinges on how they feel the possible outcomes
    could or could not be, and weighing the costs of doing something against nothing against the reflection of various possible scenarios of the outcome of who is right or wrong on the matter climate change and responsibility for it.

    Statistical Analysis Debunks Climate Change Naysayers
    [Thompson Rivers University] Newswise, (08 Mar 2007)

    http://www.connotea.org/user/msredsonyas?start=10
    …” ‘A Type I error implies that you have accepted that global warming is caused by humans when in fact it is not, while a Type II error implies the opposite,’ he says”…It is obvious that a type II error, being unaware that global warming is caused by humans and maintaining our current living styles, is much more serious than a type I error which argues that humans are the cause when they are not, in terms of the costs,” he says.”…”The cost of changing behaviour and taking action now is estimated at one percent of global GDP and this can be seen as an investment from a long-term perspective: investing in cleaner technologies and also putting a price tag on the use of our atmosphere. If we delay as we would do if we accepted that climate change is not human-caused when this conclusion was false, we would be faced with a huge cost,” warns Tsigaris.”

  16. s.ball:

    Carl Wunsch should sue them for frauding him and the public. Frauding- missleading the public should be considered a big crime!

  17. John A:

    Temperature leads CO2 by 800 years in the ice cores. Not quite as true as they said, but basically correct; however they misinterpret it. The way they said this you would have thought that T and CO2 are anti-correlated; but if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its so small. The correct interpretation of this is well known: that there is a T-CO2 feedback: see RC again for more.

    Where is the misinterpretation? If T rise precedes CO2 rise by eight centuries then CO2 cannot be forcing T rise.

    Unless of course you’re claiming that positive feedback implies going backwards in time, in which case all bets are off.

    Carbon dioxide rise appears to be a delayed response to temperature rise. The fact that the current T rise is happening during a CO2 rise implies nothing at all, because its almost certainly a spurious correlation that does not imply causation.

    Also in the ice core record, carbon dioxide continues to rise AFTER temperatures begins to fall, so no feedback is event there either.

    [Response: Try and get your head around the idea that two different things can be happening at the same time. One, the ocean and terrestrial carbon cycle is affected by climate. Two, the amount of CO2 in the air affects the greenhouse properties of the atmosphere. Part I is obvious from the paleo-record, Part II is measured in lab experiments and in observations. Together they do a pretty good job at explaining how cold it gets during the ice ages – which are paced by Milankovitch forcings. Without the radiative effect of the GHG changes, the ice ages would not have been so icy. There, that wasn’t so difficult, was it? – gavin]

  18. Ray Lopez:

    Let’s see…according to you, the program was basically correct, just subject to different interpretations caused by backwards-looking GCMs. Thanks for your opinion. Move on now, nothing here…

    RL

    CO2 doesn’t match the temperature record over the 20th C. True but not relevant, because it isn’t supposed to.

    The troposphere should warm faster than the sfc, say the models and basic theory. As indeed it does – unless you’re wedded to the multiply-corrected Spencer+Christy version of the MSU series.

    Temperature leads CO2 by 800 years in the ice cores. Not quite as true as they said, but basically correct;

    [Response: I think you might be getting it after all. The errors made are usually in what observable facts imply, only occasionally are the ‘facts’ in error too. You are supposed to think that the radiative impact of CO2 somehow means that nothing else affects climate, or a long term trend implies that there no short term fluctuations are possible, or that a very slow connection between climate and CO2 implies that there is no connection the other way around. Logical fallacies all. Surely they can do better than that? -gavin]

  19. Reasic:

    Thanks for these answers, guys. This post, especially when combined with the ones that you’ve linked at the bottom have been very helpful in answering questions I’ve received. It sure beats researching each specific claim.

  20. Chris:

    I guess it’s possible to imagine, being charitable to the C4 executives, that they thought commissioning this may foster debate. It’s a misconception – dissemination of information fosters debate; dissemination of misinformation only fosters confusion.

    It seems that there’s a great opportunity for a budding internet broadcaster here! Edit out the key points from the documentary and then add in the scientific rebuttles outlined above. There’s even scope to approach Wunsch to add some material and maybe anyone else who was swindled into appearing. To do it properly, put in some of the genuine big names in climate change, and add a 5 minute piece at the end on political involvement in scientific broadcasting ala comment #14 above.

    Then the ball is in Channel 4’s court – would they have the guts to broadcast something like that? Maybe back to back with Al Gore’s film for a night on climate change?! Or if they’re scared of the baton, how about the BBC? And if not, there’s always youtube and free Internet broadcasting…

  21. Mike:

    re #5
    Good old Pete Best – beat me to the punch again. On another associated media matter is BBC’s “Have Your Say” website. Their “Most Recommended” comments list on GW is an eye opener for me and makes me realise just what a mountain you chaps’ll have to climb to get your message across.

    Keep up the good work

    Mike

  22. Paul D:

    In the UK, TV has to follow certain guidelines, one is:

    “Due Impartiality and Due Accuracy and Undue Prominence of Views and Opinions”

    Rules include:
    “5.7 Views and facts must not be misrepresented. Views must also be presented with due weight over appropriate timeframes.”

    Because the show was advertised as being ‘partial’ to start with, it was probably legitimate. In other words, viewers were given fair warning of the content. However 5.7 could have been broken??

    If anyone in the UK is interested in complaining about the show then Ofcom has a complaints prodedure. The full set of rules are also available on the site.

    Ofcom

  23. Francis Massen:

    Re #7 and #9: Talking about “trivial arithmetic errors” please remember the embarassing 02Feb07 edition of IPCC’s SPM. Even good (and many!) scientists are not immune to errant calculations!

  24. Fernando Magyar:

    Re #13

    While I don’t think I disagree with your overall point, I am somewhat amused whenever I read or hear someone say something like this:

    “Scientific issues are not even the issue. *Real* people have significantly more power than any *scientists* due to their ability to capture the attention of the congressmen/women who can indeed, change or enact legislation that WOULD effect a change.”

    I also understand why the *real scientists* of RealClimate try to keep political discussion out of this blog as much as possible and attempt to keep the focus on the science of global warming.

    They just want us all to keep it *Real*! :-)

  25. Barton Paul Levenson:

    [[They also stated that volcanic emissions of CO2 far exceeded those from human activity. This is untrue. Annual emissions from volcanoes are only 1% of the amount emitted to the atmosphere by humans.]]

    Even better — according to the USGS, humans emit 150 times more CO2 than all the volcanoes in the world.

  26. tamino:

    The blogosphere hoopla over “the swindle” was less than I expected. I haven’t seen it (didn’t get it in my area), but from what I’ve heard, it wasn’t even very good as propaganda goes. Also, a number of sites have done a good job debunking it.

    Someone commented that RealClimate isn’t really well-tuned to the skeptical lay reader. Perhaps that’s true, but I think RC fills a more useful role by helping to educate those of us who are scientists, or very science-savvy lay readers, but not climate scientists, giving us a pretty solid non-researcher’s foundation in climate science. This enables lots of us to carry the message forward much more effectively.

    RC is not just a source for reliable, detailed climate science. It’s also helping to create an army of advocates who advance the cause with considerably more rigor and correctness. This not only helps us refute the oft-ridiculous claims of close-minded skeptics, it also makes for a stark and illuminative contrast between those who actually work at learning about the issue, and those who just “spout off” without getting their facts, or their reasoning, anywhere near correct.

    So RC, keep up the good work, and don’t change your approach. You’re not just setting the record straight, you’re helping the “disciples” fight the good fight, with truth and reason. Rabbet, Reasic, Lynn V., myself, and others, all rely on you — and we’re carrying the banner forward.

  27. Nathan Rive:

    Is anyone going to make a formal complaint to Ofcom? I had a look at the regulations before the show was aired, and I couldn’t see anything that they broke. As long as you aren’t claiming that you are presenting the news, there is no requirement for impartiality, I think.

    Thoughts? I’m a UK resident, and would be happy to partake/help out in a complaint – if there was any grounds for it.

  28. J McKeown:

    Critique by Sir John Houghton
    of Channel 4 “Great Global Warming Swindle”

  29. P. Lewis:

    Re #23, Francis Massen

    Yes. The very thought occurred to me as I penned my comment, but …

    The difference, surely, is between peer-reviewed published material (IIRC in both instances) and a policymakers’ document that was undergoing constant revision up until the moment it was published.

    The difference is that the SPM errors were acknowledged and rectified immediately, and were no more that drafting errors resulting from a decision to change to consistent units (presumably from disparate sources with regard to the now Table 1), whereas I don’t think the errors “elsewhere” have been acknowledged as errors and corrected in print/retracted (Or have they? Someone tell, please, so that I don’t labour under a false premise.) and they lead to false results that naysayers still seem to raise/use as fact in contrarian arguments.

    No contest, no comparison, I think. Errors are a fact of life: confess/retract/amend and move on; don’t retreat and hope people forget and then use your results as scientific fact.

  30. Geoff Wexler:

    Question to experts please.

    Items which were new to me.

    1. The graph comparing “Sun” with Arctic-wide Surface Air temperature Anomalies over last century.
    They actually referred to a paper! I managed to find the source i.e.
    Willie W-H. Soon ,2005 Geophys Res.Lett.Vol. 32,L16712

    Now Realclimate have criticised earlier work by him but not referred to this one (as far as I know). The icon in TAR from e.g. the Hadley centre shows that you can only account for the GLOBAL temp. over a similar period without BOTH solar and CO2 (and aerosols). So these two pieces of work appear to disagree.

    Unlike that work, this is not based on a model but on a correlation. I have not had time to read the paper yet but that probably means that they just multiply the solar energy by a scaling factor and plot it on the same graph as T. Unlike the other comparison, both curves include the last thirty years warming. The Sun curve is a bit too flat over the recent period but it does not look too bad. The temperature is not of course the global value but it seems to have similar trends. I wonder what the experts think? It is not only CO2 which Soon appears to omit but also the aerosols during the global cooling phase after 1940.

    Has there been any fiddling here? There is more to the paper than this graph (but not much more to the TV programme, the rest of it was just recycled stuff).Some time ago I read a similar comparison by Solanki et al which still concluded that you needed to include CO2 to get a good fit. That was also done without a theory)

    2. In the case of the very long term changes it is believed that the orbital changes might act like a pacemaker with CO2 feedback acting as the amplifier. Is it possible that something similar might happen when you combine cosmic rays with CO2 ? (This question has nothing to do with Soon). That assumes that the correlations between solar and T are real.

    3. As I remember the direct solar effect would not cool the stratosphere which is an argument against solar being responsible for all the warming.
    What about the indirect effect (cosmic rays)? I have only a vague idea but here is a start:
    If short wave radiation is reflected from a low level cloud it might just
    be aborbed on its way out by the stratosphere ; this could warm the stratosphere or if the effect is too small it would produce zero effect. hence less low level clouds=> more warming and zero or slight cooling of stratosphere. On the other hand some clouds produce a greenhouse effect and reducing those would reduce the stratospheric cooling. This ramble suggests that this is not the right discriminator. Is it possible that there is another signature which could discriminate between cosmic rays (clouds) and CO2?

    4. Another Lindzen crit. of climate models. He said (in the program) that extremes of weather were caused by the difference in T between the poles and the equator. This difference is projected to fall so you would expect that this would reduce the incidence of extreme weather events. Am I right in think that this appears reasonable but that it would have to be combined with the opposite effect produced by shifting a normal distribution sideways which increases the frequency of what were previously rare events? This leads to the next question : Is it possible that Lindzen’s effect is actually there in the output of the models? (this would turn the topic into a straw man).

    5. My main conclusion from the film is that there is a need for something to replace/add to Al Gore’s film. Something between Realclimate (a bit too technical) and Gore (too little physics and too open to questions about lags). In a popular account it does not matter if SOME of it is a bit too advanced for some people. Being too simple makes it easier to misrepresent. Channel 4 can always claim that they have carried other programmes puting the consensus view. The trouble is that they have not been nearly as good as some of the material on the web. The right level used to be that of the early Horizon (BBC2). Unfortunately the recent versions of Horizon emphasise entertainment rather than education.

  31. Hank Roberts:

    So, who paid for that program? Advertiser-sponsored?

  32. Brian:

    I’ve posted some more of the screenshots from the programme here.

    For the 800 year lag, it is interesting that they cite Caillon et al.. They must have missed the conclusion, which says:

    “Finally, the situation at Termination III differs from the recent anthropogenic CO2 increase. As recently noted by Kump (38), we should
    distinguish between internal influences (such as the deglacial CO2 increase) and external influences on the climate system. Although the recent CO2 increase has clearly been imposed first, as a result of anthropogenic activities, it naturally takes, at Termination III, some time for CO2 to outgas from the ocean once it starts to react to a climate change that is first felt in the atmosphere. The sequence of events during this Termination is fully consistent with CO2 participating in the latter ~4200 years of the warming. The radiative forcing due to CO2 may serve as an amplifier of initial orbital forcing, which is then further amplified by fast atmospheric feedbacks (39) that are also at work for the present-day and future climate.”

    By the way, what is your take on this?

  33. Phil:

    has anyone ID’d the data set presented in the graph (capture.jpg). To me it pretty clearly disagrees with the series I usually see, and if it could be identified as being incorrect then that would be a basis for a formal complaint.

  34. P. Lewis:

    Since swindle means to practise fraud; deceive or cheat for purposes of gain; a specious or false representation; a pretence

    I think all you non-fraudsters, non-deceivers and non-cheats out there in the climate community have a bona fide case against defamation by the programme maker and the broadcaster.

  35. Iain:

    Regarding BBC HYS debates, I’m of the opinion that they get ‘hit’, not just on climate change.

    Channel 4 is supposed, as part of it’s charter, to produce minority interest and controversial programmes. Of course if the programme contained substantial falsehoods and misrepresentations a concerted effort by bloggers and others might force a response from Channel 4. Widespread dissemination of Sir John Houghton’s response would be a good start.

    On a related note – anyone hear BBC Fivelive’s Up All Night last night? They had a guest on, whose name I missed, who went through a real script of contrarian memes. Never heard anyone say ‘there is no science behind it’ so many times.

  36. Daniel C. Goodwin:

    I have only one quibble with this article: the overly-polite usage of the word “skeptic” to describe doctrinaire denialists, as in the oxymoronic phrase “skeptic talking points.” A true skeptic would question this absurd script they have to parrot, though this performance presents no difficulty to mercenary denialists. Call ‘em what they are, and God bless ya.

  37. Dave Rado:

    Re:

    “Of course if the programme contained substantial falsehoods and misrepresentations a concerted effort by bloggers and others might force a response from Channel 4. Widespread dissemination of Sir John Houghton’s response would be a good start.”

    I would encourage those who are concerned about falsehoods and misrepresentation to write to Ofcom: http://www.ofcom.org.uk/complain/, with special reference to Section 265 of the 2003 Communications act at http://www.opsi.gov.uk/acts/acts2003/30021–i.htm#265, and sections 5 and 7 of the Ofcom Broadcasting Code at http://www.ofcom.org.uk/tv/ifi/codes/bcode/.

    Also see the update re. filling in of data at http://scienceblogs.com/stoat/2007/03/the_use_of_damon_and_laut.php. :-)

  38. Dave Rado:

    Carl Wunsch has emailed me again; some of the email is confidential but I am allowed to pass on the following statement from him:

    Fundamentally, I am the one who was swindled. I was approached, as [it was] explained to me, because I was known to have been unhappy with some of the more excitable climate-change stories in the British media, most conspicuously the notion that the Gulf Stream could disappear, among others. When a journalist approaches me suggesting a “critical approach” to a technical subject, my inference is that we are to discuss which elements are contentious, why they are contentious, and what the arguments are on all sides. To a scientist, “critical” does not mean a hatchet job—it means a thorough-going examination of the science. The scientific subjects are complicated, worthy of exploration, debate, and an educational effort with the public. Hence my willingness to participate. Had the words “polemic”, or “swindle” appeared in these preliminary discussions, I would have instantly declined to be involved.

  39. Dave Pert:

    It was a documentary expressing an opinion about the weather, not a speech denying the holocaust. It’s worth keeping that in perspective. As a member of the great unwashed, I found it quite interesting. The graph of solar activity certainly seemed a better fit to the temperature graph than the co2 graph was. And people ARE making a lot of money out of the current media “crisis”. The documentary contained a much more rational argument than any I’ve seen in the UK media, or heard from the UK government. People here in Scotland are getting rich by selling the “carbon rights” to trees which are currently 2 inches tall.These are bought by oil companies to justify air travel.
    Humanity needs to clean up it’s environmental act. But that should be done for it’s own sake, not because we’re being terrorized into it. It seems very convenient that the west gets to cripple the developing world in the process.
    I don’t know, I’ve got an open mind. Can anyone else here say that?

  40. Susan K (not a scientist ) just a card carrying member of the evidence based community):

    Are any of you scientists here able to join the Step it Up campaign to make the Fossil Fools in the Senate pass effective Climate Change Legislation? Barbara Boxer has developed legislation that per the UCS is effective:
    http://www.dailykos.com/story/2007/3/10/151341/862

  41. Dave Rado:

    Hi Dave

    If you have an open mind, as you say, I trust that means you want to see the strictly scientific evidence, and not anyone’s spin; so I would strongly recommend you start by reading the following peer reviewed scientific paper about that graph:
    http://stephenschneider.stanford.edu/Publications/PDF_Papers/DamonLaut2004.pdf

    .. and then read the following scientific evidence-based article and the links from it:
    http://www.realclimate.org/index.php/archives/2005/07/the-lure-of-solar-forcing/

    Dave

  42. Dick Veldkamp:

    Re #39 Keep an open mind about AGW?

    Dave,

    Certainly it’s a good thing to keep an open mind if a question is still open. But the fact is that there’s lots of interconnected evidence that global warming is occurring, and that present warming is caused by rising CO2 levels because of anthropogenic emissions. (For a summary of that evidence, there’s for example IPCC’s AR4, or Al Gore’s movie.)

    Then there’s a thing that seems to be overlooked by proponents of alternative explanations (e.g. the cosmic ray hypothesis). If I want to make an alternative explanation stick, not only do I have to make the case for that alternative, but also explain why the perfectly sound physics of the CO2-warming theory would NOT work in this particular case.

    There comes a time when the evidence is so overwhelming that “keeping an open mind” just becomes silly. I am not open minded about the Earth being flat, about people having built the perpetuum mobile, or about the concensus view of AGW.

    The jury has reached a verdict, Your Honour.

  43. shindig:

    I was alerted to this programme when I saw it advertised on the front page of the Competitive Enterprise Institute’s site a couple of weeks back. The CEI coordinates the US’s “Cooler Heads Coalition” and has received around $2 million from Exxon 1998-2005.

    I hear also that Channel 4 wants there to be a huge controversy about the doco. That there’s not much attention being paid to it apart from some excellent blogs ripping apart the science, like RealClimate, is therefore a good thing. We’ve heard all the arguments endlessly, always aired by the same people: Singer, Lindzen, Michaels, Christy, Ball… blah blah.

    That Carl Wunsch was misled was bad – possibly does form the basis of a complaint. I know of several other NGO’s and scientists who were also interviewed – but not included. They all debunked the rubbish run by Durkin.

  44. Geoff Wexler:

    Dave (Re: 1st.and last sentences of comment number 39).

    Your term holocaust may appear far fetched especially if you live in the Northern part of the World, but imagine a future international court.
    Witness for the prosecution: take a look at the projected rainfalls for North Africa for later in the 21st century, if the temperature were to rise (e.g. in the Summary report of the AR4). It was already rather hostile territory in 2007; then these projected rises showed a changed colour on a map which meant human casualties
    in the future. The report also attributed these changed colours to human produced CO2. But the map was ignored and the casualties occurred. What has the defence to say? Witness for the defence decides to play a recording of this TV program.

    As for the convenient crippling of the third world; this accusation is directed against enviromentalists rather than the scientists, but it is based on a straw man because (as far as I know) I have not heard of environmentalists who want to stop Africans increasing their tiny carbon footprint.

  45. fieldnorth:

    Is it possible to test for variations in low cloud with solar spot activity? I understand satellites can’t accurately measure this, because of overlying clouds. Is there any other way?

  46. Steve Reynolds:

    Re:29
    >The difference is that the SPM errors were acknowledged and rectified immediately…

    I was not aware that the IPCC ever acknowledged the errors. Is there a link where they did?

  47. Colin:

    I have no idea where the truth lies in any of this, but I come down on the sceptic side, because I believe if there really was a problem, the government would, as an example, drop VAT to zero on all energy efficient goods, cars etc, to encourage the masses to buy items that are good for the environment. Simplistic i know, but if governments can wage war for no reason, then they have the power to do this.

    I do believe that conservation of the earths resources is a sensible and responsible thing to do.

    Could all you climate scientologist answer me a few questions?

    Why can’t all you people who really know get together and present a totally unbiased and impartial, scientific paper on what is really happening, declaring all sources of funding etc? Ideally the funding should be blind i.e all industrial companies and all green companies should contribute, but without knowing which groups of scientists they were contributing to and without “leaning on” you guys to get the answer they want.

    Why can’t the funding be completely without strings, i.e. “Here you are Mr. Scientist, here is a lot of money, go away and tell us the truth, no politics, just truth”?

    Is this too much to ask?

  48. Ray Ladbury:

    Carl Wunsch’s predicament reminds me again of the divergence between the meanings of words in science and the common vernacular–and the near parity transormation between scientific and political jargon. We as scientists need to be aware that we don’t speak the same language as the general public. To this end, I would urge every scientist to read Helen Quinn’s excellent editorial in the January 2007 Physics Today: “Belief and knowledge – a plea about language”.

    http://ptonline.aip.org/journals/doc/PHTOAD-ft/vol_60/iss_1/8_1.shtml

    Especially in scientific issues that affect public policy, we need to learn to present our results to the public in language they will understand.

  49. Regina:

    RE Comment #47, “Simplistic i know, but if governments can wage war for no reason, then they have the power to do this.”

    Ever heard of capitalism? Corporations in America have more rights than human beings. Furthermore, corporations don’t have grandchildren and they don’t breath oxygen. No one can get elected to the government in America without millions of corporate dollars behind them.

    Learn more about capitalism here:
    http://en.wikipedia.org/wiki/Capitalism

  50. Ed Sears:

    re Colin 47
    First of all, they are ‘scientists’ not ‘scientologists': see Wikipedia on the Church of Scientology.

    Second, the IPCC reports seem to meet your requirements: they are signed off by most governments in the world so the views expressed are accepted not only by progressive countries eg Sweden but also deeply-fossil-fuel reliant places such as Saudi Arabia, or big industrial nations such as the USA or China.

  51. Sonny Khan:

    For those of you who want to complain to Ofcom about it here is a model complaint I found on http://portal.campaigncc.org/node/1820 :

    Model complaint to Ofcom and Channel 4
    Submitted by jimroland on 9 March, 2007 – 20:20
    The following complaint has been profferred as a model for anyone else who wishes to complain.

    It was drafted by someone who used to work for the Advertising Standards Authority and the ITV internal regulator.

    Feel free to use it in your responses to Ofcom and Channel 4, and forward it to anyone else who was outraged that Channel 4 aired the programme with no caveats. A copy of the Broadcasting Code items apparently breached appears at the foot.

    (I’ll be adding that it appears Channel 4 profited handsomely by broadcasting this with a bumper crop of advertisers, in spite of the apparent breaches, so I hope Ofcom will fine them for more than this profit.)

    You can complain via:

    Ofcom: http://www.ofcom.org.uk/complain/progs/specific/

    Channel 4: >http://help.channel4.com/SRVS/…

    Dear Ofcom

    I am making a formal complaint about the Channel 4 documentary The Great Global Warming Swindle.

    This programme is grossly irresponsible in misleading Channel 4’s viewers about the impact of climate change and the need for action. In doing so I believe it breached the Broadcasting Code clauses: 5.5, 5.6, 5.7, 5.8, 5.9, 5.10, 5.11 and 5.12.

    The programme maker and all the sources used are well known for their lobbying against climate science. Indeed the presenter Michael Durkin has a previous ruling against him for a similar breech of the Code with Channel 4’s ‘Against Nature’. It is clear therefore that this team requires stricter regulation and I urge you to require pre-clearance for any further programming from this source.

    Here are the specifics of my complaint:

    Breach of clause 5.5: Man made climate change is clearly a matter of industrial, political and public policy controversy. The Great Global Warming Swindle failed to show due impartiality towards the science of climate change and failed to represent opposing views.

    Breach of clause 5.6: Channel 4 made no indication of The Great Global Warming Swindle being part of a linked series of programmes and it is not part of any series that a viewer can identify.

    Breach of clause 5.7: The Great Global Warming Swindle repeatedly expressed views as if they were facts.

    Breach of clause 5.8: The professional and career track record of Michael Durkin where at no point explained to viewers nor was he introduced nor did Channel 4 add a caveat at the end of the programme.

    Breach of clause 5.9: The programme comprised personal views (presented in the guise of facts) and no balancing views were included.

    Breach of clause 5.10: The personal views in The Great Global Warming Swindle were not signalled as such.

    Breach of clause 5.11: Climate change is clearly a matter “of national, and international, importance” and Channel 4 should be heavily censured for failing to apply the Code in this context.

    Breach of clause 5.12: As for 5.11, given the gravity of the issue Channel 4 is seriously failing in its duty by not complying with your ruling that a “wide range of significant views must be included and given due weight in each programme or in clearly linked and timely programmes. Views and facts must not be misrepresented.”

    I am not a person who leaps to censorship or to stifle genuine scientific debate. But this programme falls far short of that, being merely the last gasp of lobbying by the US petroleum industry. Channel 4 has a track record of breaching Ofcom Codes and I urge you to exact the most severe punishment available to you for what I can without exaggeration call ‘a crime against humanity’.

    Yours sincerely

    ……………….

    Relevant Broadcasting Code clauses:

    The preservation of due impartiality

    (Rules 5.5 to 5.12 apply to television programme services, teletext services, national radio and national digital sound programme services.)

    5.5 Due impartiality on matters of political or industrial controversy and matters relating to current public policy must be preserved on the part of any person providing a service (listed above). This may be achieved within a programme or over a series of programmes taken as a whole.

    Meaning of “series of programmes taken as a whole”:

    This means more than one programme in the same service, editorially linked, dealing with the same or related issues within an appropriate period and aimed at a like audience. A series can include, for example, a strand, or two programmes (such as a drama and a debate about the drama) or a ‘cluster’ or ‘season’ of programmes on the same subject.

    5.6 The broadcast of editorially linked programmes dealing with the same subject matter (as part of a “series” in which the broadcaster aims to achieve due impartiality) should normally be made clear to the audience on air.

    5.7 Views and facts must not be misrepresented. Views must also be presented with due weight over appropriate timeframes.

    5.8 Any personal interest of a reporter or presenter, which would call into question the due impartiality of the programme, must be made clear to the audience.

    5.9 Presenters and reporters (with the exception of news presenters and reporters in news programmes), presenters of “personal view” or “authored” programmes or items, and chairs of discussion programmes may express their own views on matters of political or industrial controversy or matters relating to current public policy. However alternative viewpoints must be adequately represented either in the programme, or in a series of programmes taken as a whole. Additionally, presenters must not use the advantage of regular appearances to promote their views in a way that compromises the requirement for due impartiality. Presenter phone-ins must encourage and must not exclude alternative views.

    5.10 A personal view or authored programme or item must be clearly signalled to the audience at the outset. This is a minimum requirement and may not be sufficient in all circumstances. (Personality phone-in hosts on radio are exempted from this provision unless their personal view status is unclear.)

    Meaning of “personal view” and “authored”:

    “Personal view” programmes are programmes presenting a particular view or perspective. Personal view programmes can range from the outright expression of highly partial views, for example by a person who is a member of a lobby group and is campaigning on the subject, to the considered “authored” opinion of a journalist, commentator or academic, with professional expertise or a specialism in an area which enables her or him to express opinions which are not necessarily mainstream.

    Matters of major political or industrial controversy and major matters relating to current public policy

    5.11 In addition to the rules above, due impartiality must be preserved on matters of major political and industrial controversy and major matters relating to current public policy by the person providing a service (listed above) in each programme or in clearly linked and timely programmes.

    Meaning of “matters of major political or industrial controversy and major matters relating to current public policy”:

    These will vary according to events but are generally matters of political or industrial controversy or matters of current public policy which are of national, and often international, importance, or are of similar significance within a smaller broadcast area.

    5.12 In dealing with matters of major political and industrial controversy and major matters relating to current public policy an appropriately wide range of significant views must be included and given due weight in each programme or in clearly linked and timely programmes. Views and facts must not be misrepresented.

    The prevention of undue prominence of views and opinions on matters of political or industrial controversy and matters relating to current public policy

    (Rule 5.13 applies to local radio services (including community radio services), local digital sound programme services (including community digital sound programme services) and radio licensable content services.)

    5.13 Broadcasters should not give undue prominence to the views and opinions of particular persons or bodies on matters of political or industrial controversy and matters relating to current public policy in all the programmes included in any service (listed above) taken as a whole.

    Meaning of “undue prominence of views and opinions”:

    Undue prominence is a significant imbalance of views aired within coverage of matters of political or industrial controversy or matters relating to current public policy.

    Meaning of “programmes included in any serviceâ�¦taken as a whole”:

    Programmes included in any service taken as a whole, means all programming on a service dealing with the same or related issues within an appropriate period.

  52. P. Lewis:

    Re #46, Comment by Steve Reynolds

    On the front page of the IPCC’s 4th SPM, prominently displayed, since 5 Feb, have been the words

    Note:
    Text, tables and figures given here are final but subject to copy-editing.
    Corrections made as of February 5th, 2007

    Hands up! How many of you have read page 1? In fact, IIRC, the initial release had pretty much the same text about being subject to copy-editing, but with the issue date of 2 Feb.

    Given such warnings on the front of that document, one should expect there to be typographical and transcription errors, particularly considering the amount of redrafting the final agreed text had to go through to meet the requirements of all interested parties by the self-imposed press deadline. There are over 50 drafting and draft contributing authors listed on the cover of the 4th SPM, each, no doubt, having editorial input and with varying degrees, also no doubt, in English language abilities. Added to that will undoubtedly be the slew of subeditors making their contributions. Errors are to be expected.

    The 4th SPM is not peer-reviewed work; it is a distillation of published peer-reviewed work these last 4 years or so that will make up AR4. For anyone even to try to seek to compare the IPCC’s 4th SPM transcription/copy-editing errors with possible (and definite) errors in method in peer-reviewed publications (and I’m not saying you are) is ludicrous. Of course, if there are errors perpetuated from the original peer-reviewed work from which AR4 will be drawn and from which this 4th SPM was put together, then it is for the authors of those studies to issue errata, corrigenda, retractions, etc., in the journals in which their work was originally published. That would be a matter for them, not the IPCC. The IPCC would then, no doubt, respond.

    As I said in #29

    Errors are a fact of life: confess/retract/amend and move on; don’t retreat and hope people forget and then use your results as scientific fact.

    So, yes (at least in my mind), the IPCC have been about as upfront as possible with regard to acknowledging copy-editing errors in their document for policymakers. I can’t think of anything more prominent than putting that disclaimer and the date of amendment on the front page of the report.

    But all this is to divert attention from that scandalous piece of TV on C4.

  53. Lynn Vincentnathan:

    RE “Temperature leads CO2 by 800 years in the ice cores,” I don’t think they are claiming no correlation, but rather that if A causes B, then B cannot cause A. That’s very faulty logic.

    I use this example in class: Which causes which — re education and income? And students answer that better education leads in general to higher income. Then I pose this situation: What if parents have higher incomes, won’t their children be able to get better educations, in general?

    As for GHGs following temperature rises, that is just what I’ve been bleeping about many times: surely we are headed for a spiralling out of human control situation, if we do not reduce drastically. The initial warming, caused by our GHGs, could trigger nature to emit GHGs, causing further warming, causing further emissions, causing further warming. This is indeed a much more serious situation that simply GHGs causing warming (and no positive feedbacks involving GHGs) — which implies that we can more leisurely consider whether or not to reduce, and just how little to reduce, and, afterall, it’s sorta nice not to have to shovel snow.

    We are on a runaway train, shovelling coal as fast as we can, headed for a big cliff. There will be a point, beyond which even if we reduce our GHG emissions to zero, the train will not be able to stop in time and it’s over the cliff for many of us & much of earth’s biota.

  54. Lynn Vincentnathan:

    And they’re talking about being swindled out of what? Couldn’t be money, because measures to reduce GHGs save money. Couldn’t be freedom, because once you’re off the grid, you’re a lot freer than the matrix guys plugged into the grid. So what are we swindled out of???

    But just for the sake of argument, supposing we do have to pony up some money at some point, after we’ve reduce our GHGs by 3/4ths and technology has not come up with any more new conservation/efficiency or alternature measures. What’s a few bucks, compared to losing lives — that’s the cost of not mitigating AGW, when it is indeed happening.

  55. Max Anacker:

    The arrogance of thinking that puny man is changing global climate is only exceeded by the stupidity of believing we can – and must – urgently do something to stop it. Colin is right (comment #47). We need impartial reports by scientists not scare stories. Unfortunately impartial reports don’t sell as well as scare stories, and don’t produce funding for more research (and more scare stories). It’s really all about money, and that’s what makes the world go around.

  56. Charles Muller:

    #12 and response

    Gavin, I don’t understand your answer. The CCSP report you mention does indicate a divergence between models runs and satellite / radiosonde date over Tropics, as Al Bedo suggests it. So, this issue is open, as it is concluded.
    Tropical Temperature Results (20°S to 20°n)
    – Although the majority of observational data sets show more warming at the surface than in the troposphere, some observational data sets show the opposite behavior. Almost all model simulations show more warming in the troposphere than at the surface. This difference between models and observations may arise from errors that are common to all models, from errors in the observational data sets, or from a combination of these factors. The second explanation is favored, but the issue is still open.

    I would also be interested to know if models and satellites/sondes converge on Antarctica, more broadly 60°S and poleward. Any information about that ? RSS or UAH database suggest a cooling trend 1979-2006 in lower troposphere, but most AR4 ensemble models runs indicate a sustained surface warming for this zone, already significative for the runs 2010-30, as well as of course for the rest of the century. Some say ozone play a particular role, but I don’t perceive why it should lead here to a cooling trend in lower layers of the atmosphere.

    (Maybe Christy-Spencer are supposed to be “conservative” in their estimate, but the South Pole and low latitudes trend mentioned above appears as clearly in RSS analyze, look at maps thereafter)
    http://www.remss.com/msu/msu_data_description.html

  57. Steve Reynolds:

    Re 52:
    > I can’t think of anything more prominent than putting that disclaimer and the date of amendment on the front page of the report.

    Directly stating what had been corrected and why would help improve transparancy.

    Using a file name with a different date than the original would also be useful.

  58. AndrewM:

    This is what you are up against. From Christopher Booker, a respected UK journalist who has campaigned relentlessly against government interference and bureaucracy:

    A turning point in climate change

    Only very rarely can a TV documentary be seen as a pivotal moment in a major political debate, but such was Channel 4’s The Great Global Warming Swindle last Thursday. Never before has there been such a devastatingly authoritative account of how the hysteria over global warming has parted company with reality.

    With the aid of almost every top scientist in the field, from Professor Richard Lindzen, of MIT, and Roy Spencer, the former top climate expert at Nasa, to Patrick Moore, a co-founder of Greenpeace, Martin Durkin’s superbly professional film showed how the evidence is now overwhelming that the chief cause of climate change is not human activity but changes in radiation from the sun.

    Almost the only point he did not include was the evidence now accumulating from observers in many parts of the world that a significant degree of “warming” has recently been taking place all through our solar system, from dwindling ice fields on Mars, to Jupiter, and even as far out as Neptune’s moon Triton and Pluto.

    Yet it is at just this moment, when genuine scientists are at last hitting back against the hysteria, that our own political establishment, led by Tony Blair and David Cameron, is lining up with the EU, the UN and that self-promoting charlatan Al Gore. They propose measures that threaten not only to undermine the prosperity of the developed world but to rob billions of people across Africa and Asia of any chance to escape from the deprivation that kills millions every year.

    Truly, this pseudo-religious madness has become by far the most important and all-pervasive political issue of our time.

    Yup, I’m as speechless as you are.

  59. cokane:

    ” Why can’t the funding be completely without strings, i.e. “Here you are Mr. Scientist, here is a lot of money, go away and tell us the truth, no politics, just truth”? ”

    That’s how most government granted research works. Really, this is how the theory of global warming came about, through no-strings-attached kind of research.

  60. Dave Rado:

    This is what you are up against. From Christopher Booker, a respected UK journalist who has campaigned relentlessly against government interference and bureaucracy:

    But The Telegraph has long had an incredibly anti-AGW, anti-environment agenda – not so long ago they gave 52 entire pages to the noon-scientist Christopher Monckton’s ill-informed diatribe, so I would have been surprised if they hadn’t had some coveraage of this sort.

  61. BarbieDoll Moment:

    Re 24 (13)

    …”I also understand why the *real scientists* of RealClimate try to keep political discussion out of this blog as much as possible and attempt to keep the focus on the science of global warming.”…

    I appreciate your amusement although the source of it escapes me as the point I made had to do with the power of a person, not any political relations of climate scientists…

    ” Real people have significantly more power than any scientists”

    The onus and burden for instilling individual mentality, conclusion inferring, action or non action, belief, and a logical rational thinking process would not fall upon a climate scientist.

    Not unlike a physician, they provide information. What one chooses to do with that information (believe, seek out other opinions, conduct personal research, choose alternative treatment paths, become a non complaint patient, ect) is an individual action, reaction, and process.

    The crux of my statement in relation to the power of the people is most assuredly reflected in the executive, judicial, and legislative branches of our government which are responsible for enacting changes in current law or to remedy situations that constituents wish to be changed.

    Which I previously stated and point out in my prior posting.

    [edit] The EPA was sued by environmental groups/attorneys all the way to the Supreme Court regarding the responsibility of the EPA/government to regulate CO2. And certainly there are climate scientists who have testified for both sides.

    However, that too, would have nothing to do with politics regarding a climate scientist because he was requested by an attorney to testify as an “expert” for said attorney’s case.

    It’s a routine practice of the establishment to subpoena experts to testify on their behalf because the attorney feels that the testimony of the expert would support their litigation and arguments.

    Regardless, the arguments and stance offered within any case, is a reflection of the litigants, not the expert witnesses.

    More commonly, this is merely another form of mental compartmentalization, which most people practice in the medical or scientific fields, in order to function in their job capacities in order to operate without bias, preformed conclusions, speculations, and assumptions while carrying out their job functions.

    Furthermore, many scientific and medical employers prohibit the espousing and engagement of their employees in activities in conjunction with an employees status as their employee that would not reflect the feelings or standing of the said establishment and or employer.

    Glad to have provided some amusement in your day.

  62. Ike Solem:

    Regarding the issue of temperature changes in glacial-interglacial transitions and CO2 time lags, keep a few things in mind: (1) the current rate of CO2 increase is some 30X higher than anything recorded in the ice cores, meaning that what took 1000 years in the past is happening in about 35 years now; (2) we are in the interglacial now, not coming out of a glacial period, so the comparison is of limited use in understanding the current situation (similar to trying to understand how changes in global ocean circulation will affect climate), and (3) the ‘solar issue’ is often poorly reported; the orbital solar forcing is the one that drives the ice ages, and that relies on the changes the distribution of sunlight on the surface of the Earth due to changes in the Earth’s orbit over thousands of years, not on changes in solar energy output.

    The fact that CO2 reliably tracks temperature and doesn’t vary randomly in the ice core records should be a clue that the two are closely related – and we also know that the increase in atmospheric CO2 is due to fossil fuels by looking at the carbon-14 content (nil in CO2 produced from ancient fossil fuel deposits). CH4 also tracks temperature with a similar time lag. This also explains why we come out of glacials at all – because the orbital forcing alone is far too low to account for the observed warming.

    By the way, note that when cows and other ruminants release methane, they are getting the carbon for the methane from grasses, which photosynthetically fixed the CO2 from the atmosphere (and the methane gets converted back to CO2 within a few decades in the atmosphere) – so it’s a different proposition from using buried fossil fuels for transportation.

    As far as the political and public relations issues, it seems a lot like the tobacco campaigns aimed at disconnecting lung cancer and cigarette smoke, rather than the ongoing attempts to prevent evolution from being taught in schools – the only way to slow global warming and associated climate change is to stop burning coal and oil, and instead rely on renewables for energy – and it’s a rather large economic disruption for the fossil fuel industry. The methods used are similar to those of the tobacco campaigns – for example, CO2science.org digs up local temperature records that show cooling and presents them as evidence that the planet isn’t warming – rather like digging up a 80-yr old ‘lifetime smoker’ without lung cancer and claiming that that proves there is no link between cancer and smoking.

    Incidentally (#60), much of the earlier work on climate, weather and the oceans was actually funded by the military, who wanted in-depth knowledge of the oceans, as well as information about how infrared was absorbed by the atmosphere. Some of the earliest evidence of global warming at the poles was collected by US submarines that measured the declining thickness of Artic sea ice. It’s also noting that most of the early work on global warming predates any concern about rapid climate change, but was simply aimed at understanding the glacial cycles and the behavior of the oceans and the atmosphere.

    From the comments and discussion, it also seems that the film avoided discussing the polar regions and the high-altitude glaciers, where the evidence is pretty incontrovertible that decades-old predictions of the effects of global warming are becoming reality.

  63. BarbieDoll Moment:


    Muzzling discussion of polar bears
    March 7, 2007
    http://blog.seattlepi.nwsource.com/environment/archives/112466.asp


    …”Check out this FWS polar bear 1″ notice http://blog.seattlepi.nwsource.com/environment/library/FTApprovalPerham.PDF and this FWS polar bear 2″notice http://blog.seattlepi.nwsource.com/environment/library/FTHohn.PDF sent from the regional office in Alaska to the director of Fish and Wildlife stating that workers will not comment on these issues. In one case “an official representative” from the department will travel with the worker and is allowed to speak on the topics, someone who “is knowledgeable on the administration’s position on climate change and related issues.”…


    The House bears down on Fish and Wildlife policy on climate change
    March 9, 2007
    http://blog.seattlepi.nwsource.com/environment/archives/112521.asp


    …”The congressmen asked for all documents related to foreign travel and all records and communications on the administration’s policy on climate change, polar bears and sea ice. Deadline for compliance is March 23.”…

  64. rasmus:

    Watching the film on YouTube, it strikes me that some of the graphs (e.g. one allegedly from NASA GISS, http://data.giss.nasa.gov/gistemp/graphs/) look differently to what I remember them as. And Lindzen points out that the temperature between the Poles and the Tropics affects the storminess – as he state, the text books say – but he forgets that increased temperature also enhances the rate of evaporation. These are just a couple om impressions, but there are more… (mostly addressed elsewhere at RC.)

  65. P. Lewis:

    Re #57

    Using a file name with a different date than the original would also be useful.

    Since when you hit the download link you go to the latest edition of the report with the last revision date prominently on, I see no benefit. I think it’s a non-issue.

    If you think it is important, and you obviously do, then contact the IPCC about it. I’m sure they’ll be happy to receive your comment, and they may agree with you.

  66. Iain:

    Thought I’d email the Telegraph:

    Dear Sir,

    Christopher Booker’s choice to defer to the views of such figures as Richard Lindzen and Roy Spencer is of course his prerogative. To refer to them as “…almost every top scientist in the field” is a fiction.

    Regards,
    Iain ___________

  67. Nick Riley:

    My take on the following posts;

    # 47 “I have no idea where the truth lies in any of this, but I come down on the sceptic side, because I believe if there really was a problem, the government would, as an example, drop VAT to zero on all energy efficient goods, cars etc, to encourage the masses to buy items that are good for the environment. Simplistic i know, but if governments can wage war for no reason, then they have the power to do this.”

    As Benjamin Disreali once said “England is governed by Parliament not by logic”

    #55 “The arrogance of thinking that puny man is changing global climate is only exceeded by the stupidity of believing we can – and must – urgently do something to stop it.”

    So “puny man” was not responsible for punching a hole in the ozone layer by emitting CFCs (in the tiniest of quantities compared to the total mass of the atmosphere).

    Actually that is what we need. Global agreement to limit CO2 greenhouse gas emissions directly- just like the Montreal Protocol has done for CFCs. Interestingly, the models that predicted in the 1970’s that CFCs would deplete ozone did not predict that the hole would develop. It was the shock of the discovery of the hole in 1985 that spurred international action to control CFC emissions. The models had not taken into account the role of Polar Stratospheric Clouds. So- a point that the skeptics miss is that models can actually underestimate how bad things can get. Prior to 1985 there were many arguments posed against limiting CFCs- that parallel what we hear today about not doing anything about GHGs- “too expensive- no alternative technology- will damage the economy- etc etc.

    Do we ever learn from history? I hope that we do not need to wait for a “shock” re climate change before we get appropriate and binding global action to reduce GHG emissions.

    Nick Riley

  68. Dave Pert:

    re 41 – cheers for those, Dave. Good sunday morning reading.It strikes me,as a non-scientist, that both sets of graphs are fairly meaningless unless we know whether the background cosmic radiation is a constant or not. Are there any hypotheses relating to this? Also, I’ve been looking at a couple of forums who take the opposite view to you guys. They cite that water vapour is a much more significant greenhouse gas than CO2. Could the current escalation in temperature have anything to do with the increase in atmospheric water vapour caused by the last 150 years of natural warming? It would seem to follow, at least to a layman like myself.
    re 42 – I hate to tell you, but you don’t get to decide when a question is open or not. Hindsight will be our ultimate judge. If there are people who oppose you, then the debate’s still open. It would be so convenient if it were otherwise. I come from an Arts background, and studied the philosophy of science whilst at Uni. If I remember correctly ALL scientific truths are, and should be, open to debate and eventual revision. I find the “we’ve decided, and so that’s the truth” attitude that I see on this board reasonably abhorrent. I have some respect for the peer review system, but I do not let this blind me to the fact that scientists are humans and will fall into camps, hold allegiances, play politics, and dismiss their opponents out-of-hand just like the rest of us. The peer review system is also compromised by the inconvenient truth that the majority of climate-research funding comes from bodies who are trying to prove a specific point. This is no “golden age” of research. Anyone who begs to differ will be, effectively, working themselves out of a job. People (and I include scientists in this generalisation)don’t tend to do this. I imagine that the cell-phone in my pocket, which gives my a mild headache after 20 minutes use, was proved to be safe for children by a series of peer-reviewed articles.
    re 44 – Thanks for likening me to a war criminal. Raised a chuckle on a dull sunday morning in Aberdeen. It strikes me that climate modelling is so tenuous that no court would ever entertain it as evidence.
    In general – Like I say, I’ve got an open mind. I sympathise with the pro-warming camp. You’re saving the planet. The glamour of that must be overwhelming. But what if you’re not? That also has to be considered. Like I said previously, humanity needs to clean up it’s act. Our squandering of resources is disgusting on a fundamental level,regardless of any apocalyptic consequences. This needs addressed, no question.
    Finally, please stop the Channel4-bashing. This is infantile, and smacks of pro-censorship. Channel 4 has a government mandate to produce challenging and controversial programming. It is obvious from this thread that it has sparked debate with this documentary. That can only be a good thing. It’s made me aware of some of the underlying issues that would otherwise have escaped me. This striving to “shoot the messenger” begs the question “what kind of world are you trying to save?”. One where the likes of myself get shown footage of random glaciers and hurricanes and are terrorized into doing our governments bidding, rightly or wrongly?

    Oh yeah, as a seasoned documentary watcher, I have to ask: how does the global-dimming thing fit into modern climate modelling? Just curious…..

    [Response: Global Dimming and Climate Models – gavin]

  69. Barton Paul Levenson:

    [[Critique by Sir John Houghton of Channel 4 “Great Global Warming Swindle” ]]

    Houghton is one of my heroes, not just because he has the climate science right, but because he was willing to e-mail me, a complete stranger, electronic versions of the tables from his book “The Physics of Atmospheres” (2002 version). He is a gentleman as well as a scientist.

  70. Barton Paul Levenson:

    [[I don’t know, I’ve got an open mind. Can anyone else here say that? ]]

    No. You are the only one. In fact, you may be the only one in the world. Lonely there at the top, isn’t it?

  71. Barton Paul Levenson:

    [[Why can’t all you people who really know get together and present a totally unbiased and impartial, scientific paper on what is really happening, declaring all sources of funding etc? ]]

    That’s what the IPCC is all about. But the conclusions from there get called a fraud and a swindle by the denialists. Your mistake is in thinking that people want an unbiased review of the evidence. Most just want their own prejudices confirmed, and will ignore or denounce anything to the contrary.

  72. Barton Paul Levenson:

    [[The arrogance of thinking that puny man is changing global climate is only exceeded by the stupidity of believing we can – and must – urgently do something to stop it.]]

    An individual man may be puny, six billion humans with an advanced industrial technology are not. We can, and must, urgently, do something to stop the increase in greenhouse gases that is heating up the world.

  73. Craig Truglia:

    1. The graphs posed are only decent proof. Numbers can be manipulated, as made note of in the film. Their numbers must be regarded with skepticism.

    [Response: The graphs were manipulated as well. The temperature changes claimed to come from NASA certainly did not: http://data.giss.nasa.gov/gistemp , the solar correlation used discredited calculations and were deliberately cut off around 1980 to hide the obvious disparity since then etc. – gavin]

    2. The documentary’s filmmaker is very biased and misrepresents certain things, mostly the accreditations of the scientists. For example, one scientist labeled as the former head of the National Weather Center was really the former head to the National Satellite Weather Center. Furthermore, he used leading questions and was uncritical of weather data collected over hundreds or thousands of years using in my opinion, questionable methods. The only sound measurements we have are from statellites since the seventies. Everything else declines in quality.

    Nonetheless, this is not a huge criticism. After all, the film does not pretend to be balanced, unlike Michael Moore’s Bowling For Columbine. Its filmmaker is no more questionable than Al Gore from An Inconvenient Truth. So, why should we automatically discredit what a lot of scientists say, because the filmmaker is nutty? We seriously give Al Gore’s and Moore’s ideas consideration, and ignore the messenger. Thus, we should care more about the arguments and science given, and not the filmmaker. The only reasopn people are so critical is because this is a right wing documentary. Quite frankly, we need to be objective.

    [Response: No. we are critical because they were wrong on a huge number of issues and implications – not because they are partisan. – gavin]

    Nonetheless, the film still has a lot to teach you. Furthermore, the arguments used against it from the press amount to ad hominems. Realclimate.org attempted a scientific refutation. Their slogan is “Climate science from climate scientists.” I will disprove their counter-arguments, not to show my brilliant understanding of the subject (I am not a climate scientist,) but the very poor understandings being peddled by “talented” scientists.

    Their article can be found at http://www.realclimate.org/index.php/archives/2007/03/swindled/

    1. They try dodging the fact that CO2 does not correlate with temperture:

    “CO2 doesn’t match the temperature record over the 20th C. True but not relevant, because it isn’t supposed to. The programme spent a long time agonising over what they presented as a sharp temperature fall for 4 decades from 1940 to 1980. . . . They presented this as a major flaw in the theory, which is deeply deceptive, because as they and their interviewees must know, the 40-70 cooling type period is readily explained, in that the GCMs are quite happy to reproduce it, as largely caused by sulphate aerosols.”

    So, the sulfate aerosoles stopped cancelling out the warming magically between the 40s and the 70s, but not before the 40s or after the 70s? This is nothing more than adapting the old logic of the disproven global cooling theory of the 70s. Nevertheless, one need look no further than the fact that there is data (Christy and Spencer’s satellite data, balloon data, antarctic temperatures) that show cooling until around 1998. So, their neat and tidy aerosal explanation is not air-tight. Quite frankly, neither is the solar only theory (at least using the solar data used in the film.) Data is easily manipulated and exceptions easily construed. We should avoid gross simplifications, but I do find it funny that when a skeptic makes such a simplification that they are called out for it, when climatology is chock full of them (and very poor ones.)

    [Response: All single factor explanations are wrong. The only way to assess this is to have all factors weigh in and then see which (if any) dominate in any particular time. The factors over the 20th C are dominated by greenhouse gases but until recent decades variations in other components were still important. The difference between aerosols and CO2 is that CO2 accumulates, while aerosols are related to current emissions – implying that the CO2 effect will dominate in time. See http://www.realclimate.org/index.php/archives/2005/05/planetary-energy-imbalance/ for some idea of what the factors look like in time and how the modeled temperature responds. – gavin]

    2. They claim that the troposphere is warming more than the surface…

    “The troposphere should warm faster than the sfc, say the models and basic theory. As indeed it does – unless you’re wedded to the multiply-corrected Spencer+Christy version of the MSU series. Christy (naturally enough) features in this section, though he seems to have forgotten the US CCSP report, and the executive summary which he authored says Previously reported discrepancies between the amount of warming near the surface and higher in the atmosphere have been used to challenge the reliability of climate models and the reality of human induced global warming. Specifically, surface data showed substantial global-average warming, while early versions of satellite and radiosonde data showed little or no warming above the surface. This significant discrepancy no longer exists because errors in the satellite and radiosonde data have been identified and corrected. New data sets have also been developed that do not show such discrepancies. See-also previous RC posts.”

    If you bothered reading the next paragraph of that report it said: “For recent decades, all current atmospheric data now show global-average warming that is similar to surface warming. . . . The majority of these datasets show warming at the surface that is greater than the troposphere.” Thus, the troposphere is not warmer “indeed” than the surface. [edit]

    [Response: Over short periods (such as the satellite record) even the models show that you can’t expect monotonic behaviour. Indeed the model trends span the range of observed trends making any ‘discrepancy’ very hard to detect. Given the history of corrections to the satellite data, the significant difference between UAH and RSS products and problems with the radiosondes, claims that this disproves models are specious. -gavin]

    3. They claim that the ice cores, which don’t show an increase in CO2 until a change in temperature first, is misleading:

    “Temperature leads CO2 by 800 years in the ice cores. Not quite as true as they said, but basically correct; however they misinterpret it. The way they said this you would have thought that T and CO2 are anti-correlated; but if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its so small. The correct interpretation of this is well known: that there is a T-CO2 feedback: see RC again for more.”

    They add in an article they link at, “The reason has to do with the fact that the warmings take about 5000 years to be complete. The lag is only 800 years. All that the lag shows is that CO2 did not cause the first 800 years of warming, out of the 5000 year trend. The other 4200 years of warming could in fact have been caused by CO2, as far as we can tell from this ice core data.”

    “COULD in fact”??? Yet, this is the “correct interpretation”??? This makes NO sense. First, whatever made the world warm is STILL happening before the increase in CO2. Second, the most they can be claiming is that the world got warm naturally first for 800 years, and then the other 4200 years were caused by a new runaway CO2 warming. However, this is just guessing and does not explain why the CO2 would stop warming at year 5,001. What independent force stops the warming then? The fact is, they are coming up with seemingly logical excuses that do not hold up to even the most unintelligent (mine) scrutiny.

    [Response: You would benefit from reading about Milankovitch forcings. The changes in the ice cores are (on these timescales) driven by wobbles in the Earth’s orbit that affect the seasonal distribution of solar radiation. These are independent of anything else going on. The carbon cycle, particularly in the ocean responds to these changes over a long time period – related to the ocean mixing time – and subsequent changes in CO2 also make it cooler and so on. This is a classic and well-known feedback. Your conceptual problem is that (as above) you need to accept that climate is not driven by any single factor, but that all need to be accounted for – including human behaviour. CO2 is leading now because we are changing it very directly and no amount of ice core data will shift that understanding. – gavin]

  74. Iain:

    “They cite that water vapour is a much more significant greenhouse gas than CO2. Could the current escalation in temperature have anything to do with the increase in atmospheric water vapour caused by the last 150 years of natural warming? It would seem to follow, at least to a layman like myself.” Dave.

    Dave, you’ve found realclimate, there is a good article about water vapour to be found right here. You might find that you have it backwards.

    [Response:Water Vapour: Feedback or Forcing? – gavin]

  75. Ray Ladbury:

    Re 47, 55. Colin and Max, I make it a point to try to reach out to skeptics. If my extended hand is met with the back of yours, at least I am none the worse for it.
    First, to address Max’s complaint. Actually Max, humans have had a tremendous effect on the planet. Humans caused extinction of all the large animals on Madagascar and in Australia. They may have played a role in the advance of deserts like the Sahara through overgrazing. There is strong evidence that in addition to “global warming”, we also influenced climate by dumping aerosols into the atmosphere (this is what called the cooling that skeptics often trumpet as “proof” that scientists don’t know what they’re talking about). You need to remember that we are talking about 6 billion puny humans, not just a few. A carpenter ant in isolation looks harmless, too, but a few tens of thousands can take down your house.

    Now to address Colin’s post. First, the reason science and politics cannot be divorced is precisely because science is a human activity, and politics is how groups of humans get things done (polis–“the people” is the root of politics). The difference is that scientists have agreed to be bound by certain rules, and rule #1 is that the evidence prevails. Now, they can argue what the evidence means for a long time. Ultimately, however, a consensus emerges when there is just too much evidence for one particular theory to argue convincingly against it. There will still be “skeptics” and contrarians who argue against it–hell there are still particle physicists who don’t believe in the unification of the weak nuclear and electromagnetic forces. But rule #2 in science is that a strong consensus prevails–and experience shows that that consensus is very rarely wrong. (Note: Science is only about 300 years old, and medical science is really only about 100 years old, so don’t go all flat-earth and spontaneous-generation on me.)
    In a way, science works like markets–some buyers are willing to pay too much or too little, just as some sellers have unreasonable expectations. Ultimately, though a price is agreed and those willing to sell and buy can do so. It is the best method we’ve come up with to determine a “fair” price.
    Likewise, it is hard to look around you and argue that science doesn’t work. This is just science working normally. There is no more controversy over climate change within the scientific community than there is over evolution or relativity. It is just playing out under the spotlights and microscope of media attention.
    One expert can be wrong, as can two. However, when nearly ALL the EXPERTS–people who have studied a field for decades–agree, and you reach the opposite conclusion and are not an expert, then you have to consider the possibility that they understand the field of their expertise better than you do.

  76. Colin:

    Comment 50: re Colin 47
    “First of all, they are ‘scientists’ not ‘scientologists': see Wikipedia on the Church of Scientology.” Ouch! I assume you were not meaning to be patronising and yes I do know the difference. Now if only i could type ;-)

    Comment 55: Comment by Max Anacker

    Wow! I hope you are one of those scientist guys and not scientologists :-)

  77. hopp:

    Your “rebuttal” of the documentary seems very weak to me. You concentrate on the easier, more obvious points and ignore the more difficult ones. You don’t show any sense of uncertainty, despite the vast complexity of the matter in question. The reply to this documentary here and elsewhere has been 98% political above all. I consider myself a radical green, but not at the cost of rationality and free speech. The calls to censor these views are nonsense, compared to the much more wild and non-scientific stuff that has been printed in the name of raising GW awereness (a central green politician in my country even managed to mention the asian tsunami and GW in the same context). The role of the sun is the central question here I feel (not pretending to be a scientist). Because it offers a very logical and plausible explanation. “Even” the recent IPCC report admits that there is “10% possibility” man is not affecting the climate. And how do you really count it’s 8% or 17% or 24%. It either is, or isn’t. The figure is arbitrary, yet quoted over the world as some sort of statistical certainty.

    Also it is true that Global Warming “hysteria” started as a very strong and fastly growing political movement some 17-18 years ago, when there was only very little data to back-up the hypothesis. And we do know how much Greenpeace have utterly lied and spread misinformation about nuclear energy.
    Since then (the early 1990’s) government funding and man made GW being real have gone together, hand in hand. It is a very valid question to ask, whether this has affected the research. If there is no problem (or severe doubt whether a problem exists) then there will be less funds available, and unemployed climatologists out looking for jobs.

    Also censorship of disagreeing peer reviews in the IPCC report strikes me as something that is foreign to science and open minded thought. Your comments on that?

    The question about computer models being unpredictable, the role of water vapor etc. are also valid ones. And how much do we really know about cloud formation, cosmic rays etc.? All these things from sun to CO2, to whatever (because the world is very complex) should be somehow put together into one model. Now the models only can predict so much, or very little to be more exact.

    The AGW (and I’d agree with the pre-cautionary principle) agenda doesn’t come across as very scientific. Even reading the IPCC paper, it is true, you keep asking yourself “isn’t this an assumption, how have you proven this, aren’t these factors too complex to assess” etc.

    Yet.. the agenda is driven forward with 100% certainty and scientific disagreement is looked upon like it was some sort of environmental form of holocaust denial, while non of these scientists in the film are actually getting paid for it, they aren’t getting any grey corporate dollars like the greenpeace-minded lobby are claiming to. To the contrary it should be underlined, that these IPCC scientists do have a personal financial agenda to “prove” that no doubt or disagreement exists any longer on man made GW. The more central the agenda becomes, the more funds, more job opportunities, more recognition they will be getting. It would a career suicide for them to radically change the course, even if reasons for scientific doubts kept arising. You don’t have to mislead people, it’s enough to concentrate on certain aspects and keep feeding them into computer models that give the right answers. That’s what’s been happening partly. You don’t get a sense of overall picture from the IPCC reports. Water vapor, sun etc. uncertainty is wiped under the carpet.

    From a purely rational point of view, you should say the GW is a hypothesis, and one that is extremely hard to verify or substantiate. At the same time playing Russian roulette isn’t wise, that much is true.

    Yet there is too much religious approach to this question, too much political agenda.

    Personally I don’t trust anyone who claims to speak for the truth.

    Science should be about constant research, doubt, self-criticism. I have seen very little of that on this website, or other scientific (or portraying to be such) AGW websites. Science seeks answers. Here it is the other way around. The answer has been “self-evident” from the beginning, even when there was next to no data to back it up. An answer that cannot be valsified, only verified. In any case time will tell, because China, India, Indonesia, Brazil etc. are growing at a speed that will make EU and USA a small player in the Global AGW battle. Today 30% of Global CO2 emissions. In 2023 it could be 14% (USA+EU combined that is).

    The man made GW conviction is bordering on religious, that much is true from the critics. Not driven by pure science, but political motivation above all and you should come out clear on it (that there is the anti-west angle, despite west in todays world attributing only to 1/3 of the global total). Don’t cloud the pre-cautionary principle into a cloud of scientific assumptions, that remain just that in the larger picture, a hypothesis.

  78. Colin:

    Comment 71:

    “Your mistake is in thinking that people want an unbiased review of the evidence. Most just want their own prejudices confirmed, and will ignore or denounce anything to the contrary.” Comment by Barton Paul Levenson

    Good point – I just want an unbiased view from the people that understand these things better than me and then we can direct funds into resolving the problem, if indeed there is a problem that can be resolved.

  79. Colin:

    Comment 59: (Why can’t the funding be completely without strings) “That’s how most government granted research works. Really, this is how the theory of global warming came about, through no-strings-attached kind of research.”

    Comment by cokane

    Are you serious? So why is eveybody doing research into Man Made Global Warming and not just Global Warming or is this something else I don’t understand?

    I am genuinely interested and open minded enough to be converted to the MMGW camp.

  80. Colin:

    Comment 75: Thanks Ray, I think that was a good answer, and I do accept that people know more than I do, especially those who are experts in their field, however, you must remember that eugenics, abhorrent as it is, was an academic discipline at many colleges and universities prior to the 1930’s and had many prominent advocates.

    Could you or anybody else explain the following taken from the National Geographics web site?

    “Earth is currently experiencing rapid warming, which the vast majority of climate scientists says is due to humans pumping huge amounts of greenhouse gases into the atmosphere.

    Mars, too, appears to be enjoying more mild and balmy temperatures.

    In 2005 data from NASA’s Mars Global Surveyor and Odyssey missions revealed that the carbon dioxide “ice caps” near Mars’s south pole had been diminishing for three summers in a row.”

    I know this work has been dismissed by many climate scientists, but I don’t understand why.

    Thanks for broadening my knowledge

    [Response: http://www.realclimate.org/index.php/archives/2005/10/global-warming-on-mars/ – gavin]

  81. Nick Riley:

    Re post #77
    The science of GW actually goes back to the 19th Century.

    As regards the rise of GW in the socio-political arena of modern history, it is clear that it entered popular culture during the 1960’s hippy movement. The following is from Jimi Hendrix (1967)- “Up from the skies”

    “I have lived here before the days of ice and of course this is why I’m so concerned. And I come back to find the stars misplaced and the smell of a world that is burned. A smell of a world that is burned. Yeah well, maybe, hmm…Maybe its just a… change of climate?”

    So the programme was also wrong about Mrs Thatcher being responsible for beginning the awareness of GW in recent history.

  82. Dean Morrison:

    I’ve overlaid the graph on Durkins prog referred to in the original post with the Nasa data it’s supposedly based on:

    http://img103.imageshack.us/img103/6634/sdodgygraphgm3.jpg

    Now remember we aren’t comparing two different datasets – the Durkin Graph is supposed to be based on the Nasa one – i.e it should be the same…

    You’ll notice that the amount of warming pre-1940 has been grossly exaggerated – thus diminishing the appearance of warming post 1970’s

    The labels ‘1940’ and ‘1975’ are nowhere near where they should be.

    A ‘little ‘artistic licence’ perhaps? – B****cks – this is out and out deception in a programme which accused the entire scientific community of lying about global warming. A scientist that did this would be disowned by his colleagues – and never trusted again.

    Before CH4 come up with their ‘interesting polemic’ and ‘presenting both sides of an argument’ and ‘controversy amongst scientists’ (shrug of the shoulders) defences – could I point out that holocaust deniers use exactly the same fraudulent graphs to make a case for their interesting ideas. So when does David Irving and his chums get 90 minutes to present their case unchallenged??

    Another complaint winging its way to OFCOM I’m afraid…

  83. David Kidd:

    This article was taken from Mr. Monbiot’s Blog. It gives a lot of background and explains how this program came about.
    The Revolution Has Been Televised
    Posted December 18, 1997

    “Channel 4’s Against Nature series turns out to have been made by an obscure and cranky sect

    By George Monbiot. Published in the Guardian 18th December 1997.

    There has never been a series on British television like Channel 4’s Against Nature, which ended with a debate on Tuesday night. The environmentalists it interviewed were lied to about the contents of the programmes. They were given no chance to respond to the accusations the series made. They were misrepresentated to the extent of falsification. One couldnâ��t help suspecting that Against Nature was driven not by healthy scepticism but by shrill ideology.

    If this were so, where might it have come from? At first we thought the Far Right might have been involved. But, over the last three weeks, another picture has begun to form. Against Nature IS the product of an extreme political ideology, but it comes from a rather different quarter: an obscure and cranky sect called the Revolutionary Communist Party.

    Frank Furedi, the series’ key interviewee and a protagonist in Tuesday’s debate, has been described as the father of the modern RCP. He is a regular contributer to the RCP’s journal, Living Marxism. Of the two main contributers to the third programme, one, John Gillott, is Living Marxism’s science correspondent. The other, Robert Plomin, though not RCP, has recently been interviewed sympathetically by the magazine. Martin Durkin, the director of the three programmes, describes himself as a Marxist: the only brand of Marxism which follows the line the series takes is the RCP’s. The husband of his deputy, Against Nature’s assistant producer, is the co-author of the RCP’s manifesto and Books Editor of Living Marxism.

    Line by line, point by point, Against Nature follows the agenda laid down by the RCP. Greens, both the series and Living Marxism maintain, present themselves as radicals, but are really doom-mongering imperialists, engaged in the deification of Nature and the rejection of human progress. Global warming is nothing to worry about, while sustainable development is a conspiracy against people. Greens have plotted with the film industry to make science terrifying. Genetic engineering and human cloning are not to be feared but cherished, as they will liberate humanity from nature.

    The ideologues in the series have some strange bedfellows, but the RCP has always been good at making selective alliances, whether it is promoting anti-environmental ideas, or campaigning against a ban on landmines and in favour of the Bosnian Serb forces and the Hutu militias. Its members are controversialists, but more than just that: the principle targets for their attacks are alternative outlets for radical action.

    I had scarcely broached this subject on Tuesday night’s debate when Martin Durkin began – and I do not exaggerate – screaming. I was a McCarthyite and a despicable conspiracist. What on earth did his personal political views have to do with this series?

    Well, rather too much. The RCP and its associates can make as many programmes as they like as long as they do so openly and honestly. Indeed, among its perversities and cheap controversialism, the RCP has some interesting and provocative views, which are worth hearing and debating. But Martin Durkin and his commissioning editor, Sara Ramsden, maintain that Against Nature is not a polemic, but a well-balanced documentary series. There was no presenter; instead we were instructed, in true documentary style, by an authoritative voice-over. The RCP/Living Marxism interviewees were not captioned as such, but presented as independent experts.

    It’s an extraordinary coup for a tiny group of cranks: three hours of prime time propaganda. But how on earth did they pull it off? It is inconceivable that Channel 4’s top decision-makers also belong to the party. But many television executives hate environmentalism. They see it as a grim memento mori at the bottom of the picture, spoiling the good news about cars, clothes and consumerism. So when the film-makers suggested an all-out assault on environmentalists, their proposal fell on fertile ground. The revolution, as the RCP sees it, has been televised.”

    Obviously the Brits too have their deniers. Every country does: my own country Australia certainly does. We have been held hostage by a backward conservative administration that has only changed its rhetoric because it has detected a groundswell of popular acceptance with an election coming up.

  84. Albert:

    Who is Claude Allegre?
    http://www.canada.com/nationalpost/news/story.html?id=2f4cc62e-5b0d-4b59-8705-fc28f14da388

    [Response: Con Allègre, ma non troppo – gavin]

  85. Jeff Weffer:

    One significant problem with the 800 year time lag and the comments that increasing CO2 then provided the feed-back to fully lift the world out of the ice ages is that the increase in CO2 is so small.

    CO2 increased by only 100 ppm over the period of 5,00 years as the ice ages started to end. This is far too small to provide the warming feed-back that is proposed. In fact, CO2 has increased by a further 100 ppm in the last century and we have not seen anything like the temperature increases which ended the ice ages.

    The Antarctic warmed by over 10C as the last 4 ice ages ended. CO2 increased by 100 ppm (with a very long lag-time of course.) No model or global warming theory I have seen can explain that discrepancy.

    [Response: This has been discussed ad nauseum elsewhere on this site, just do a few appropriate key word searches and you should have your answer. In particular, note that the radiative forcing associated with increased co2 is logarithmic, so the warming impact of a 100 ppm increase from 180 ppm to 280 ppm (the approximate glacial/interglacial difference) is far greater than that a 100 ppm increase from 280ppm to 380 ppm (the approximate pre-industrial/current difference). This has to do with the saturation of absorption bands within the IR window as greenhouse gas concentrations increase). -mike]

    Another question? what is the time-lag for increased CO2 to warm the surface. Since CO2 is absorbing EM radiation (photons in the IR frequency), shouldn’t global warming be near instantaneous (operating at the speed of light.) Certainly there is not a time-lag of 800 years or even 10s of years.

    [Response: No mystery there. The cooling factors that keep the peak ice ages colder are (in order of importance), the ice sheet expansion (increasing albedo), CO2 drop, CH4 drop, N2O (drop), vegetation change and dust load increases – all of those feedbacks matter. The GHG changes explain about 40% of the effect – not all of it. But the dominant change is related to the ice sheets which are strongly controlled by the insolation changes (Roe, 2007 is a good demonstration of that). The time lag for GHG increases to have a warming effect is the ocean mixed layer timescale – a few decades (as you can see over the 20th C), but that will be clear only in the absence of other effects. Since other changes will be occurring at the same time (which they must be or the CO2 wouldn’t have changed in the first place), you can’t expect an instantaneous response. On the longer timescale though the impact of the GHGs is clear which is why the last glacial maximum is such a common target for assessing climate sensitivity. – gavin]

  86. Colin:

    I don’t mean any disrespect, Gavin, but http://www.realclimate.org/index.php/archives/2005/10/global-warming-on-mars/ points to an opinion on this website, whilst 1 link leads to Duke University physicists report, which states:

    “Applying their analytical method to the solar output estimates by the Columbia group, Scafetta’s and West’s paper concludes that “the sun may have minimally contributed about 10 to 30 percent of the 1980-2002 global surface warming.

    This study does not discount that human-linked greenhouse gases contribute to global warming, they stressed. “Those gases would still give a contribution, but not so strong as was thought,” Scafetta said.

    “We don’t know what the Sun will do in the future,” Scafetta added. “For now, if our analysis is correct, I think it is important to correct the climate models so that they include reliable sensitivity to solar activity.”

    Is it any wonder that people like me are confused by the whole debate over whether man is to blame or can do anything to control the climate?

    [Response: S+W’s study is incorrect, but even if we discuss that, you can always find another ‘confusing’ reference that we haven’t discussed. This is a real problem, and one where there is not an obvious answer. Integrating the amount of differing opinions available even in the peer-reviewed literature (let alone the – ahem – less quality-controlled stuff on websites) is a full time job and even the scientists who do this for a living find it difficult to keep up. So as a layman, it’s tricky. That’s why the assessment process is so important – I’ve often said that the public shouldn’t listen to any one scientist (even me), but the assessments (IPCC, NAS etc.) are generally much more considered and take into account all the different factors. That’s why we generally refer people to those rather than to my opinion or something in a peer reviewed paper. You don’t have to believe me, but we really do try and give the considered opinion of the community here, not an agenda-driven cherry pick of the science. – gavin]

  87. Craig Truglia:

    Gavin, your responses detract from your original propositions. Essentially, all 3 of your counter-arguments are that “no one factor contributes to global warming.” This is very true and I agree with that. However, that is precisely the problem with the man-made global warming proposition: that largely one factor can be isolated and attributed to global warming. Your responses, though logical, do not really denounce the points made by an unscientific documentary with scientific claims.

    Furthermore, it is concerning that you ignored the following:

    Me: If you bothered reading the next paragraph of that report it said: “For recent decades, all current atmospheric data now show global-average warming that is similar to surface warming. . . . The majority of these datasets show warming at the surface that is greater than the troposphere.” Thus, the troposphere is not warmer “indeed” than the surface.”

    [Response: Over short periods (such as the satellite record) even the models show that you can’t expect monotonic behaviour. Indeed the model trends span the range of observed trends making any ‘discrepancy’ very hard to detect. Given the history of corrections to the satellite data, the significant difference between UAH and RSS products and problems with the radiosondes, claims that this disproves models are specious. -gavin]

    Regardless of your issues with UAH’s dataset, you still ignore that the study you sight to “prove” that trophospheric warming is “indeed” greater than surface warming says in plain English the complete opposite.

    I am more than happy to admit that the documentary has its flaws. But, you and others here have to admit that your counter-arguments to the documentary are flawed as well…sometimes blatantly such as in the above example. If this whole issue was more science and less ideological bickering, I think we would see more level-headed and balanced responses from both sides. This is not something I see, but not being a scientist (while those on this espouse of being such), it is pretty concerning that you cannot even link to articles that agree with you or your own articles that definitively in theory show that the 800 gap is from a clear cause. I believe the writers of this article should issue a retraction, admit their mistakes, and issue a valid response or not at all. The 3 points above, as the main ones taken to deswindle the swindlers, are shoddy at best and poor at worst.

    [Response: The points were raised in the programme as if they were obvious contradictions that mainstream scientists were ignoring. We point out that the supposed contradictions are nothing more than well worn talking points that sound to the layman that they might have something to with the issue at hand. The lag issue is a complete red-herring, the sfc/trop issue is more ambiguous but the data spread and model spread overlap and so there is no contradiction. The temperature trends over the 20th Century are well matched by climate models and it takes five minutes googling to show that those trends are best matched by using all relevant forcings. These are not serious scientific points worthy of debate – they are mere talking points designed to snare the unwary. You should be able to spot the difference. -gavin]

  88. Dean Morrison:

    “Watching the film on YouTube, it strikes me that some of the graphs (e.g. one allegedly from NASA GISS, http://data.giss.nasa.gov/gistemp/graphs/) look differently to what I remember them as. ”

    You’re not the only one that noticed this – the simplest way to compare is to superimpose the two:

    http://img103.imageshack.us/img103/6634/sdodgygraphgm3.jpg

    Where you can see that amongst other things they’ve greatly exaggerated pre 1940 warming to play down the dramatic recent warming.

    – well and a few other things of course – I’ve commented in more detail on Ben Goldacre’s ‘Bad Science’ forum:

    http://badscience.net/forum/viewtopic.php?p=32125&sid=ff3edd7b046f639e7683cd388ef9e531#32125
    tinyurl.com/2mo7cl

  89. Ray Ladbury:

    Re 80. Colin, when you talk about climate on other planets you need to be aware that each planet has it’s own climate forcers that are important for it. Thus, just as there is little danger of Earth experiencing a runaway greenhouse effect as Venus did, what happens on Mars may tell us little about what is going on here on Earth. In particular on Mars, in the absence of liquid water, dust beomes one of the driving factors, with hellacious dust storms blocking out sunlight at odd intervals. The “warming” on Mars occurred bucause of a paucity of these storms during the period in question. (Note: this is a shortened version of the reasoning in the post Gavin cited, just in case you don’t have time to read it thoroughly.) The sure sign that the warming on Mars is no smoking gun is the fact that the experts on Martian climate haven’t pounced on it to show how much smarter they are than their colleagues looking at climate on Earth.;-)
    The reason why most climate research these days is looking at greenhouse gases and anthropogenic causation is mainly because there is simply no other credible hypothesis. We can and do measure solar radiation. We measure galactic cosmic rays (guess what–no change in the past 30 years aside from what’s expected from the solar cycle). And so on. As Sherlock Holmes said, “When you eliminate everything that is impossible, whatever is left, no matter how seemingly improbable must be the answer.” That’s anthropogenic greenhouse gas emissions. Also, while most of the current research is looking at this cause, it is by no means the only research going on. The quickest way for a scientist to get famous is by discovering something his or her colleagues haven’t thought of. Lindzen and Svensmark think they have done so, but they have yet to produce sufficient evidence (any, really) to persuade experts that they are right.

  90. Colin:

    Comment 81

    I thought Up From the Skies was about Hendrix’s feeling of alienation, hinting at a possible belief in people from other worlds. He begins by wanting to talk to the people who live in the 60’s / 70’s tower blocks

    “I just want to know about your different lives
    On this is here people farm
    I heard some of you got your families
    Living in cages tall and cold”

    and depending on which website you take the lyrics from could equally say

    “Yeah well, maybe, hmm…
    Maybe it’s just a change of climate”

    i.e. no spaces between “a” and “change” giving the sentence a different meaning

  91. Ray Ladbury:

    Re 77. Hopp, you seem to have a few misconceptions about climate research. First, the 90% “probability” that humans are contributing to climate change is probably more of a Bayesian probability–a conservative estimate that the vast majority of experts could agree on. You might also look at it as a confidence level–in other words there’s only a 10% probability that the results could line up the way they have by chance or via some other mechanism. For Earth sciences, this is high confidence indeed.
    The most serious misconception, though, is the idea that climate scientists have a dog in this fight–they don’t. If anthropogenic climate change were disproved tomorrow, they would be doing research on something else. Even those who did not find jobs in climate research would find jobs doing models for hedge funds or something else more remunerative than climate research. The people who do this research do it because they think it is important. They see that changing climate represents a variety of threats to modern human civilization, and they want to do something about it. To impugn their integrity by implying that their puny salaries could buy their scientific opinion is not just flat wrong, hell, not even just laughable, it is insulting.
    Since you, yourself, are not a scientist, and since virtually ALL the experts have concluded that climate change is occurring and that we are responsible for it, don’t you think that you ought to consider the possibility that they, with their decades of research and study, might understand it better than you?

  92. Brian:

    For those that might be interested, I’ve made an image showing the graph from the programme, overlaid with the NASA GISS temperature data (black and red lines).

  93. Bishop Hill:

    Can anyone help me? I’ve read this from RC which explains the mainstream explanation for the CO2 rise lagging T.

    Q1: If there is a feedback mechanism, what stops it accelerating exponentially?

    Q2. Is the mechanism by which T initially starts to rise still not understood?

    Thanks

  94. Robert Smith:

    If you are disappointed/angry at the propaganda that was The Great Global Warming Swindle here is where to complain:

    http://www.ofcom.org.uk/complain/progs/specific/?itemid=286480

    Complain to C4 itself:

    channel 4 complaint form

    or complain to the advertisers:

    Volkswagon, Hastings & Direct, Bradford & Bingley, Visa, Yakurt, Orange, Audi, Virgin Media, Mitchelin, Zurich finance, Wrigley (orbit gum), Ing Direct (finance), Magners Cider, confused.com (insurance), Christian Dior (J’adore), Kraft foods (Toblerone, Cote d’or), Nat West, Love Films, Citreon, Nissan, Expedia, Microsoft, Ibuleve, Otex ear drops.

  95. Unwashed random#:

    Please don’t be too hard on C4. I’m here reading your fascinating comments as a direct result of watching “it”. I want to be sceptic about AGW but I accept rigorous science.
    It seems to me that to be safe we must act to do the least harm and most benefit. Holding back emerging economies from developing would certainly condemn another generation to grinding poverty and early death. It might be easier for us to adapt to a warmer climate than explain ourselves to the developing world if dT turns negative for the next 30 years.
    Can anyone point me to work done on plant carbon fixing as a result of an extended growing season in northern land masses?

  96. hopp:

    You simplify the issue. It’s not insulting at all. There are many scientists out there looking for jobs, who would love to have this level of funding the climatologists enjoy. I’m not doubting their sincerity. But the fact is the political truth existed before the scientific consensus. And 90% and 10% is nothing really, the numbers are arbitrary. Correct me if I remember wrong, but in the previous IPCC report (not the latest one) it was estimated that the earth would warm 1.4C-5.8C if nothing was done to curbe the CO2 emissions. I mean 1.4C-5.8C, what is that? Why not 1.3C or 6.1C? How do you count it with so many different factors from solar activity to cloud formation, to water vapor, to CO2 emissions etc.

    No one scientist can really handle the issues of GW in one single piece. No one can claim to have such expertise. Everyone is relaying on others, and trusting their authority. It’s like a puzzle that is placed together, with many of the parts missing and then it’s run through man made computer models, that naturally cannot even come close to matching the complexity of the climate.

    You have made it into a religion. [edit]

    You have your answers ready made. One example. gavin here (if I remember correctly) linked to an article that was supposed to disprove the cosmic rays factor, but all the article was to distort the words of the Nordic scientist, compare him to some guy from 1850’s (personal attacks again), and then what he really had in store to debunk the cosmic ray theory was that, well… we don’t know enough about it yet.

    [Response: You completely misread the article. The point was not however very subtle – there is a possibility that GCR affects climate which I have frequently acknowledged. However, that is not to say that the evidence presented for it has been convincing (it hasn’t not by a long shot) and the spin that the scientists involved have put on it is extremely misleading and unjustified by the evidence. People who are convinced by the GCR/climate connection – especially for the modern period – cannot possibly have been paying attention. The contrast between the evidence for greenhouse gas forcing of modern climate change and GCR is huge, and no objective observer could think otherwise. -gavin]

    Even Einstein held faith in his special theory in face of growing evidence. As long as AGW remains unproven one way or the other, and we have to rely on suggestive evidence, conclusions and models, healthy skepticism should be encouraged. And this would be the case in any other scientific question (with the possible exceptions of GM and such – for similar reasons). Every single time some dears to criticize AGM he is attacked in person, he recieves hate mail, threats and abuse and is – often wrongly – accused of ties to oil/coal companies.

    That’s not how science works. That’s politics.

    [Response: Well, you’d be pretty surprised at some of the mail I get as well. The ties to oil and coal companies aren’t a complete determinant of the quality of someones argument, but in my experience it is generally quite telling. I note however that in denying receiving any such money Tim Ball was let us say ‘being economical with the truth’. He is heavily funded by lobbyists like the High Park Group and ‘Friends’ of Science both of which get substantial funds from such companies, and he prefers not to ask where the money is coming from. But as I said that is interesting but irrelevant for the quality of the arguments made. The arguments are specious – and their proponents know it full well. That is what you should be appalled at. – gavin]

  97. Ike Solem:

    Regarding the comments about ‘puny humans’, one might as well talk about ‘puny ants’ or ‘puny elephants’, both of which also have large effects on their local environments, or ‘puny phytoplankton’.

    For example, compare the effects of humans to that of glaciers – you’d think glaciers would be the real powerful earth-moving force, but it turns out that people cause ~10X more soil erosion than all other processes combined; see http://www.sciencedaily.com/releases/2004/11/041103234736.htm

    Humans also account for a large fraction of the global photosynthetic production; see Global patterns in human consumption of net primary production, Imhoff et al 2004 Nature

    The human population and its consumption profoundly affect the Earth’s ecosystems. A particularly compelling measure of humanity’s cumulative impact is the fraction of the planet’s net primary production that we appropriate for our own use. Net primary productionâ��the net amount of solar energy converted to plant organic matter through photosynthesisâ��can be measured in units of elemental carbon and represents the primary food energy source for the world’s ecosystems. Human appropriation of net primary production, apart from leaving less for other species to use, alters the composition of the atmosphere, levels of biodiversity, energy flows within food webs and the provision of important ecosystem services…”

    What’s strange is how political advocacy groups like AEI, CO2science.org, etc. immediately sieze on any such discussion of human effects as evidence that ‘humans are viewed as a cancer on the Earth by these wild-eyed environmentalist crazies’. Really, the point (as far as global warming goes) is that we need to stop pumping buried carbon into the atmosphere, and that means ending the use of coal and oil as energy sources and replacing them with renewable energy conversion and storage technologies – it’s really very simple. However, since the global economy revolves around energy sales, this means serious change – and if you own an oil well, or three, then obviously you are going to have a strong emotional response to anyone who tells you that you can no longer pump and sell oil.

    The best analogy of our current energy system is that of a small village that discovered ancient ruins filled with buried loot – the villagers began digging up and selling the treasure, and as a result grew into a large city – but eventually they are going to run out of buried loot, and digging it all up has fouled their rivers and their air – so they are in a quandry, and need to make major changes in their basic economic strategy. Vested interests are resistant to change, however, and so they hire public relations experts to prevent change from occuring, and they finance movies, books, and web sites to get their ‘message’ out. It’s an understandable response, but is very foolish in the long run.

  98. Philippe Chantreau:

    A lot of “skeptics” like to talk about water vapor but never mention the fact that combustion of a carbon/hydrogen based fuel releases both CO2 and H2O as vapor. In fact, it is the only process of which I can think that can allow an addition to the absolute amount of water on the planet, except for objects coming from space.
    Considering the vast amounts of fuel burned it should be sizable. I expect that this vapor will have simply the short atmospheric life span of all water vapor and simply join natural vapor in its cycle, but what role could the absolute increase of global water content play, if any? Has this been considered in any way?

  99. P. Lewis:

    This, I assure everyone, is not meant as an attack on any one particular person’s mental faculties or posts herein. One sees frequently people saying “I have an open mind” or “we must keep an open mind”. Fine, it’s an admirable sentiment. But, as HW Andrews said:

    While an open mind is priceless, it is priceless only when its owner has the courage to make a final decision which closes the mind for action after the process of viewing all sides of the question has been completed. Failure to make a decision after due consideration of all the facts will quickly brand a man as unfit for a position of responsibility. …

    Or perhaps more succinctly (Anon?)

    Never confuse an open mind with a vacant one.

    because, as GS Hilliard said:

    A vacant mind invites dangerous inmates, as a deserted mansion tempts wandering outcasts to enter and take up their abode in its desolate apartments.

    And there are people with personal agendas who prowl continually to ensnare the vacant minded.

    And before I leave the quotations, it is worth remembering what Alexander Pope said:

    A little learning is a dangerous thing; drink deep, or taste not the Pierian spring: there shallow draughts intoxicate the brain, and drinking largely sobers us again.

    which is a good advice for anyone entertaining discoursing on any topic herein where you draw comment from professional scientists whose day jobs are climatology and atmospheric physics. Those professional scientists have open minds and can see more of the picture than the merely open-minded (or vacant-minded) scientific dilettante. More humility, less hubris (little chance, I fear).

  100. Colin:

    Comment 99:

    “While an open mind is priceless, it is priceless only when its owner has the courage to make a final decision which closes the mind for action after the process of viewing all sides of the question has been completed. Failure to make a decision after due consideration of all the facts will quickly brand a man as unfit for a position of responsibility.”

    And you are saying that ALL the facts are in and have been given due consideration?

  101. John Lang:

    To Dean Morrison #88 and Brian #92, the differences in the charts are pre- and post-adjustment of historical temperatures by GISS and the Hadley Centre.

    Historical temperature records have been adjusted for change of location, the urban heat island effect etc. The total is about 0.5C upward adjustment in the trend.

    The documentary used the unadjusted raw data.

    Here is what the chart looked like in a National Academy of Science report in 1975.

    http://en.wikipedia.org/wiki/Image:DSCN4904-nas-a.6_crop.jpg

  102. Ray Ladbury:

    Re 96: Hopp, first, based on the most recent AGU study, 98% of recent PhDs in geo and space sciences found employment in the sciences. An AIP study found that 97 of 2003 and 2004 PhDs found employment–those statistics don’t leave much room for desperate job hunters willing to sacrifice their integrity for a job.
    Then there’s the question of motivation: Why would funding agencies want a scientist to falsify their research in favor of anthropogenic climate change. After all, most climate research funding comes from the US and other governments, and having the scientists say humans are changing the environment doesn’t exactly reflect favorably on the governments’ inaction on greenhouse gas emissions.
    It is difficult to respond to the vague accusations you make. As to having canned responses to the arguments made by so-called skeptics…well, is it Gavin’s fault that the skeptics keep using the same tired, discredited arguments? WRT the arguments about galactic cosmic rays, the main problem I see with the argument is that we have direct measurements of GCR fluxes for the past 30 some odd years (where we’ve seen rapid warming) and there is no upward trend. Last I saw, for something to be a cause, it had to be present when the effect was present. Oops! As to the occasional ad hominem attack on persistent skeptics, mea culpa. However, when you see the same tired, discredited arguments being advanced repeatedly by the same contrarians independent of evidence, you have to wonder whether the problem may not be so much with the argument as with the hominid who keeps repeating it. The number of true experts who doubt Earth is warming is pretty darned close to zero. The number who think humans have nothing to do with it can probably be counted on fingers and maybe a couple of toes thrown in. There is NO controversy in the scientific community–just the normal process of consensus with some cranks who cling to dissent for their own contrarian reasons. It is the media and public who manufacture the controversy.

  103. P. Lewis:

    Re # 100
    Sigh! “all the facts” does not necessarily mean “ALL the facts”.

    I could have qualified the quotation, but thought it unnecessary. After all, we are all intelligent people on this site, aren’t we?

    But fine if you want to play semantics, but you’ll be playing solo.

  104. Craig Truglia:

    “You should be able to spot the difference. -gavin”

    Yes, but shouldn’t you be able to source your claims about the troposphere-ground temperature differences properly? You still have not corrected your claim, which is disproved by the link to the article Spencer help write. You really should correct it, because it is a major red herring. This is leaving all over-drawn claims aside.

  105. Dave Rado:

    A lot of “skeptics” like to talk about water vapor but never mention the fact that combustion of a carbon/hydrogen based fuel releases both CO2 and H2O as vapor. In fact, it is the only process of which I can think that can allow an addition to the absolute amount of water on the planet, except for objects coming from space.

    But it’s beside the point, because it doesn’t change the amount of water *vapour* in the atmosphere, for the reasons explained at http://www.realclimate.org/index.php?p=142. But for exactly the same reasons, water vapour has no *forcing* (causative) affect on temperature changes.

  106. Ray Ladbury:

    Re 101: Boy, I’m not even sure whether that does it, unless they did some very serious “smoothing” on the data–and I mean, well beyond a 5-year moving average.
    Re 100: Colin, one thing that separates science from other forms of empirical investigation is that experiment in science is guided by understanding. The climate models and investigations already include every effect that contributes SIGNIFICANTLY to climate that we have found. The fact that they reproduce trends as well as they do (remember this is a chaotic system we’re looking at here–trends are as much as you can hope for) suggests there isn’t a whole lot else to consider that will significantly alter the conclusions arrived at to date. Every once in awhile you get a wildcard–like GCR fluxes–thrown in. But GCR fluxes have stayed the same on average (modula the solar cycle) throughout the time we’ve been able to measure them. This coincides with the significant warming seen 1975 to the present. So, how do I derive an increase from a stimulus that basically isn’t changing? Also, remember, clouds can be a source of warming as well as cooling, and why would we expect differential formation day and night from a driver of galactic origin?
    Let me again recommend Helen Quinn’s Refernece Frame Column from January’s Physics Today (link in post #48). There are things that we as scientists know. We know them in ways a layman simply cannot understand, because we’ve looked at the evidence and understand how it can be wrong and by how much. Despite this deeper level of knowledge, we will still say we “believe”. This isn’t belief; it is knowledge. That is why we are insistent that we need to do something about the threat.

  107. Eli Rabett:

    Re#56 there is something funny in the UAH MSU reconstructions at high southern latitudes perhaps driven by inclusion of albedo effects.

    Re #83 the Revolutionary Communist Party seems quite similar the the LaRouchies in the US who have also added climate denialism to their collection of pathologies.

  108. Eli Rabett:

    Hmm…#101 probably points to one of the usual suspects as the source of the odd graph. Anyone see it elsewhere?

  109. William Connolley:

    Below is the text of a letter from Carl Wunsch, reproduced with permission.

    Mr. Steven Green
    Head of Production
    Wag TV
    2D Leroy House
    436 Essex Road
    London N1 3QP
    
    10 March 2007
    
    Dear Mr. Green:
    
    I am writing to record what I told you on the telephone yesterday about
    your Channel 4 film "The Global Warming Swindle." Fundamentally,
    I am the one who was swindled---please read the email below that
    was sent to me (and re-sent by you). Based upon this email and
    subsequent telephone conversations, and discussions with
    the Director, Martin Durkin, I thought I was being asked
    to appear in a film that would discuss in a balanced way
    the complicated elements of understanding of climate change---
    in the best traditions of British television. Is there any indication
    in the email evident to an outsider that the product would be
    so tendentious, so unbalanced?
    
    
    I was approached, as explained to me on the telephone, because
    I was known to have been unhappy with some of the more excitable
    climate-change  stories in the
    British media, most conspicuously the notion that the Gulf
    Stream could disappear, among others.
    When a journalist approaches me suggesting a "critical approach" to a
    technical subject, as the email states, my inference is that we
    are to discuss which elements are contentious, why they are contentious,
    and what the arguments are on all sides. To a scientist, "critical" does
    not mean a hatchet job---it means a thorough-going examination of
    the science. The scientific subjects described in the email,
    and in the previous and subsequent telephone conversations, are complicated,
    worthy of exploration, debate, and an educational effort with the
    public. Hence my willingness to participate. Had the words "polemic", or
    "swindle" appeared in these preliminary discussions, I would have
    instantly declined to be involved.
    
    
    
    I spent hours in the interview describing
    many of the problems of understanding the ocean in climate change,
    and the ways in which some of the more dramatic elements get
    exaggerated in the media relative to more realistic, potentially
    truly catastrophic issues, such as
    the implications of the oncoming sea level rise. As I made clear, both in the
    preliminary discussions, and in the interview itself, I believe that
    global warming is a very serious threat that needs equally serious
    discussion and no one seeing this film could possibly deduce that.
    
    What we now have is an out-and-out propaganda piece, in which
    there is not even a gesture toward balance or explanation of why
    many of the extended inferences drawn in the film are not widely
    accepted by the scientific community. There are so many examples,
    it's hard to know where to begin, so I will cite only one:
    a speaker asserts, as is true, that carbon dioxide is only
    a small fraction of the atmospheric mass. The viewer is left to
    infer that means it couldn't really matter. But even a beginning
    meteorology student could tell you that the relative masses of gases
    are irrelevant to their effects on radiative balance. A director
    not intending to produce pure propaganda would have tried to eliminate that
    piece of disinformation.
    
    
    An example where my own discussion was grossly distorted by context:
    I am  shown explaining that a warming ocean could expel more
    carbon dioxide than it absorbs -- thus exacerbating the greenhouse
    gas buildup in the atmosphere and hence worrisome.  It
    was used in the film, through its context, to imply
    that CO2 is all natural, coming from the ocean, and that
    therefore the human element is irrelevant. This use of my remarks, which
    are literally what I said, comes close to fraud.
    
    I have some experience in dealing with TV and print reporters
    and do understand something of the ways in which one can be
    misquoted, quoted out of context, or otherwise misinterpreted. Some
    of that is inevitable in the press of time or space or in discussions of
    complicated issues. Never before, however, have I had
    an experience like this one. My appearance in the "Global Warming
    Swindle" is deeply embarrasing, and my professional reputation
    has been damaged. I was duped---an uncomfortable position in which to be.
    
    At a minimum, I ask that the film should never be seen again publicly
    with my participation included. Channel 4 surely owes an apology to
    its viewers, and perhaps WAGTV owes something to Channel 4. I will be
    taking advice as to whether I should proceed to make some more formal protest.
    
    Sincerely,
    
    Carl Wunsch
    Cecil and Ida Green Professor of
       Physical Oceanography
    Massachusetts Institute of Technology
    
  110. Matthew Wright:

    http://video.google.com/videoplay?docid=9005566792811497638&q=global%2Bwarming%2Bswindle

    The right wingers are distributing this around…. they have the $$$ (resources) to get this to every open wire on the planet.

  111. Nick Riley:

    Colin re your comment #90

    Hendrix was well aware of science; indeed he was fascinated by science fiction. If you follow to the last verse of “up from the skies”, it has the line, “I want to know about the new mother earth, I want to hear and see everything”. So, I think Hendrix was addressing social (poor modern city design) and environmental issues (disturbing the natural balance) in the lyrics. Also, if you listen to “3rd Stone From the Sun”, “Voodoo Chile (slight return)”, “Power of Soul” and “1983 A Merman I Should Be” there are lots of lines that refer to his appreciation of the wonder of the Earth, solar system and how humans are mucking it up (“out of style,out of style” etc).

    In any case, IMHO- it was Silent Spring by Rachel Carson (1962) set the modern environmentalist movement off on its way – of which the hippies were the first popular cultural response.

  112. Ike Solem:

    RE#98, Phillipe consider how much water is in the oceans. The water vapor feedback effect is primarily what determines the short-term (century-scale) climate sensitivity to CO2; see http://www.sciencemag.org/cgi/content/summary/310/5749/795 The undisputed facts on this matter are that the models are treating the water vapor feedback correctly, which is why the contrarians are reduced to unsupported arguments about changes in solar output causing global warming.

    RE#104 ‘forcing’ and ‘causative’ are not at all the same thing; ‘forcings’ apply to models only, as externally set variables; the ‘feedbacks’ (the internal variables that change as the model does calculations, such as upper atmospheric water vapor) are quite causative (the increased water vapor absorbs more infrared, and causes the surface to warm more). You could make a model of the glacial cycles that includes CO2 as a feedback effect to solar orbital forcing, but the CO2 would still play a causative role in the glacial to interglacial transition (this would be risky, since the specific mechanisms that cause CO2 to increase in the glacial – interglacial transition are still not well understood).

  113. Ray Ladbury:

    Professor Wunsch would perhaps be well advised to subpoena the raw footage of his interviews now. Even if he has no intention of filing suit himself, as a matter of self defense, he needs to make sure that the full story is preserved and not “edited” to support a future case–legal or otherwise.

  114. Reid:

    Gavin – could you please clarify this issue for me succinctly and without a lot of hand waving? Prior to the 20th century, does CO2 concentration lag or lead the temperature cycle?

    [Response: During the ice age cycles, it was mostly likely a lag. The degree of that lag is actually quite uncertain and there is recent paper under review that suggests with good reason that it is less than the 800 years seen in the Caillon et al study. At other points in the past, such as the Paleocene-Eocene Thermal Maximum (55 million years ago), it looks like the CO2 (or possibly CH4) lead. Over very long timescales (millions of years) the overall level of CO2 (driven by weathering/geologic balances) probably lead – and is hypothesised to have contributed to the onset of the Quaternary ice age cycle in the first place. – gavin]

  115. FredT34:

    I’m sure Carl Wunsch feels very uncomfortable being swindled. I’m sure other scientist will get fooled in next months and years. However, you scientist have to continue participating in such programs – or denialists will confiscate the whole media field… You are “our” voice – voice of responsible and worrying humans on this planet (it’s our only one, forever).

  116. James:

    Re #111: [Prior to the 20th century, does CO2 concentration lag or lead the temperature cycle?]

    Maybe a simple explanation from a non-climate scientist would help? What seems to be missing is an appreciation of the fact that for millions of years prior to the 20th century, there was essentially a fixed amount of CO2 in the atmosphere+ocean+biosphere system. The fractions in each part changed as temperatures changed – a cold planet meant more would dissolve in the ocean, for instance, and those changes caused various feedbacks. If you look at climate records such as ice cores, you see that the system has atmospheric CO2 cycling between pretty constant high & low values in sync with temperature.

    Humans changed this, by adding substantial amounts of CO2 to the system as a result of burning fossil fuels. (You can determine quite accurately just how much humans have added. Economic data for instance gives you good values for the amounts of coal, oil, and so on that have been extracted: just add it up and do the math.)

    What this means is that the historical CO2 lead/lag question is a red herring. It’s asking about the behavior of climate given a fixed amount of CO2 in the system, while AGW deals with the effects on the system of adding more CO2.

  117. gary:

    I followed you link on volcano vs. human CO2 output….

    Objection: One decent-sized volcanic eruption puts more CO2 in the atmosphere than a decade of human emissions. It’s ridiculous to think reducing human CO2 emissions will have any effect.

    Answer: Not only is this false, it couldn’t possibly be true given the CO2 record from any of the dozens of sampling stations around the globe. If it were true that individual volcanic eruptions dominated human emissions and were causing the rise in CO2 concentrations, then these CO2 records would be full of spikes — one for each eruption. Instead, such records show a smooth and regular trend.

    “Not only is this false” is not an argument. The graph shows the “inventory” of CO2 not “flow” pf CO2. This is not proof.

  118. David B. Benson:

    Re #93: Bishop Hill and maybe also #111: Reid —

    Q1. The atmospheric carbon dioxide concentration depends upon biological activity. At the last stadial (LGM) there were extensive deserts. As these began to receive moisture once again, biological activity increased. Eventually all the deserts bloomed (well, many did) and no further increase was possible due to rainfall patterns.

    Q2. Briefly, yes. There are a variety of suggested accelerant causes to assist orbital forcing in lifting temperatures (melting ice) in the first few centuries after LGM.

    Disclaimer: I am a newbie amateur at paleoclimatology. Status is 3.5 books and about two dozen papers. RealClimate, of course.

  119. ziff house:

    I’m not sure where to inject this, as it is always a little off topic. Do models predict any years of cooling or is the temperature straight up from here? Will there not be years ahead when there is some cooling, given that nature rarely moves in a straight line.I would think that such an event will be deeply harmful in so much as it will renew the ‘controversy’.

  120. Brian:

    #101 John Lang: Thanks for clearing that up. Any idea where I can get hold of the unadjusted data?

    BTW Another screenshot from the show, this time more fun. Spot the subtle mistake!

  121. John Lang:

    To Brian #115 – I don’t think you can get the unadjusted raw historical temperature dataset anymore. It has been adjusted three or four times now and only a few reseachers in the field kept the old data in between each adjustment.

    A person could try searching around GISS and Hadley Centre websites.

  122. Reid:

    Thank you, David. I found this in regard to the lead/lag character. Apparently, it is argued here that yes, there is a lag in the historical record, but it is suggested that the lagging CO2 is merely a positive feedback that enhances the subsequent warming. But, if this is the case, it begs the question of what is the stabilizing force that cancelled out the positive feedback and prevented a runaway greenhouse?

  123. Michael Strong:

    Up until the last few weeks, I trusted RealClimate as the most reliable climate blog. Ellen Goodman’s rhetoric comparing climate skeptics to Holocaust deniers drove me to investigate the skeptics for myself. I concluded that, whether or not they are right, it was (and is) simply dishonest to discredit them in the manner that is done in the media and at RealClimate. I am now convinced beyond the shadow of a doubt that there are intellectually credible scientists with relevant expertise who, acting from intellectual integrity, do not agree with the IPCC summary statements. The fact that there may be numerically few of them is perfectly irrelevant.

    These individuals may well be wrong on the substantive issues, but the frequently snide tone and ad hominem attacks on those individuals who disagree with the RealClimate perspective has reduced your credibility for me.

    On the assumption that your perspective is the correct one, and that you want to maintain credibility, I would encourage that you take a far more generous perspective with respect to the motives of those who disagree with you, and become far more patient. The magnitude of policy change that is being demanded justifies, in my opinion, a level of “audit” similar to what climateaudit demands. This is, indeed, an unusual expectation in science, but the level of policy influence that you expect should result from your science justifies that level of audit.

    While you are correct to express outrage over the manner in which Wunsch’s perspective was distorted in this documentary, I don’t believe that you expressed similar outrage when Landsea felt that his perspective was being misrepresented by the IPCC, nor did you express similar outrage when Pielke felt that his perspective was being misrepresented by CCSP Committee. Insofar as you care about the issue, and appropriate policy responses to it, your over-riding concern should be that overly-zealous advocates should not undermine the credibility of the scientific community by politicizing key bodies representing scientific consensus. To an outsider, politicized misrepresentations at the IPCC or CCSP are far, far scarier than are misrepresentations in a documentary. The fact that Lindzen predicted that this type of politicization would take place and thereby create a “consenus,” in the early 1990s, adds to his credibility.

    In the end, all you have is your credibility. As someone who once respected RealClimate, I hope that these comments will ultimately result in a more balanced tone here.

    [Response: Fair enough. These kinds of events tend to bring out the more strident of comments and because this is (for us) an old story, we occasionally get a little snarky. This doesn’t necessarily read well to the casual observer and so we probably should avoid it – but in our defense…. well, forget that. We’ll try better in future. Thanks – gavin]

  124. David B. Benson:

    Re #122: Reid — I attempted to answer this in #118. Briefly, there is only a finite amount of carbon dioxide (say, in the ocean) available to go into the atmosphere.
    Thenceforth the actual amount is controlled by the substantially increased biological activity in areas which were deserts during LGM.

  125. Charles Muller:

    #85 Mike comment

    In particular, note that the radiative forcing associated with increased co2 is logarithmic, so the warming impact of a 100 ppm increase from 180 ppm to 280 ppm (the approximate glacial/interglacial difference) is far greater than that a 100 ppm increase from 280ppm to 380 ppm (the approximate pre-industrial/current difference). This has to do with the saturation of absorption bands within the IR window as greenhouse gas concentrations increase). -mike

    If IPCC formula for CO2 radiative forcing is still correct – ln(C/Co)*5,35 – I get 2,36 W/m2 for 180>280 ppm, 1,63 W/m2 for 280>380 ppm. I woulnd’t say the 0,73 W/m2 difference is “far greater”, with a mean climate sensitivity of 0,85 K/W/m2. Or something I miss.

  126. Iain:

    William – is Professor Wunsch going to mind that letter being reproduced elsewhere on the internet? I appreciate permission is given for here, I’m wanting to be able to post it elsewhere.

  127. John Lang:

    The issue of the timelag of 800 years for warming temperatures and the increase in CO2 is not as important, in my opinion, compared to the absolute level of CO2 rise (100 ppm) versus the temperature increase (6C to 10C).

    There has been the same 100 ppm increase in CO2 over the last century and temperatures have not increased anywhere near the rise that ended the ice ages.

  128. David B. Benson:

    Re #125: John Lang — The so-called greenhouse effect is proportional to only the logarithm of the change, not the absolute level.

    The timelag issue is of interest in understanding the paleoclimate of the ice ages. The immediate, AGW, effects are rather different.

  129. Nick:

    One fault with the program was that it missed the point about C02 and its effectiveness as a Greenhouse gas. Even if its conccentration is small, if C02 is a very effective greenhouse gas, its significance is higher.

    However, on the other hand, the lead lag question is very significant. Why hasn’t it been openly discussed on this board as being a major open question? The obvious conclusion is that those presenting the board have a major bias, and fall into the same category as those earning money from oil companies.

    Just what is the explaination for the temperature leading the C02. There is a clear explaination and that is that C02 is the side effect.

    From the historical record, what is the average global temperature that corresponds to the current C02 levels?

    From the historical record, what is the average global temperature that corresponds to the forecasted C02 levels?

    What is the forecasted C02 levels and does the assumed increase correspond to the figures used in the models? ie. Is the IPCC reports 1% growth rate in C02 production consistent with the historical observations?

    How many of the IPCC committee are scientists out of the total and is their science qualifications relevant?

    The program raises serious questions that need answers.

    Nick

  130. Reid:

    #123 David: Do you have a reference which quantifies the finite amount of CO2 available for a positive feedback of this sort that I could look up? Once the oceans had been depleted of CO2, what process kicked in to re-sequester the CO2 and bring temperatures back down? And, once this process began, what prevented the newly restored CO2 from once again driving temperatures up resulting in a limit cycle at the maximum, which is what usually happens when you have a bounded positive feedback (e.g., when you have a “hot mike” forming a positive feedback loop with the speakers but the amplifier output is limited by the power source)?

  131. Steve Bloom:

    Re #125: Your point has been addressed multiple times in the comments above. Please read them. Very generally, close examination of climate behavior shows that it does not respond to forcings in a linear manner. If it did, we wouldn’t be here to discuss it. Even if it was the case that a 100 ppm CO2 increase could be expected to result in the same temperature increase regardless of the starting point, note that you assumed in addition that the response to the present rise should be nearly instantaneous. There’s no reason to think that either. That said, it might be useful for you to compare the temp increase since 1850 with the increase of any similar period during the last deglaciation. Things do seem to be moving along quite rapidly.

  132. Eli Rabett:

    #124 is simply wrong. Soils and plants account for about 2000 petagrams of carbon, the atmosphere and upper ocean about 800, the big cahuna is the deep ocean (actually it is carbonates, but they interchange with the others on millenia time scales), with about 40,000 petagrams. Now the interchange between the upper and lower oceans takes hundreds of years, which is fast enough to keep pace with orbital changes (changes associated with ice ages), but not fast enough to keep pace with the pulse of carbon that burning fossil fuels is pushing into the atmosphere. See http://www.grida.no/climate/vital/13.htm for example.

  133. David B. Benson:

    Re #130: Reid — One interesting attempt to model a feedback system for the long period ice ages is

    Barry Saltzman
    Dynamical Paleoclimatology
    Academic Press, 2002.

    There is more discussion on a thread just a few down regarding the question of what triggers ice ages. But briefly, at interstadials and interglacials, orbital forcings then allow new or renewed ice sheets to begin to form.

    But perhaps the most important comment I can make is that the physical-chemical stability of the climate system is not well understood, only (so far) observed. There is at least one journal entirely devoted to paleoclimate (Climate-of-the-Past) and one to the more specialized topic of PALEOCEANOGRAPHY. (That is the title!)

  134. David B. Benson:

    Re #132: Eli Rabett — Thank you for the correction and the link.

  135. Reid:

    David – Thank you again. I hope you see the problem here. If CO2 feedback is unbounded, then we should have observed (or not, as the case would be) a runaway greenhouse. If it is bounded, then there is still no mechanism for it to have restabilized. It would have created a limit cycle of some magnitude and regularity.

    Orbital forcings which are independent of the internal dynamics here, i.e., which do not form a loop between observables and forcings, would not be able to stabilize such an instability. I am no expert on climate systems, but I am an expert on feedback systems in general.

  136. Dave Rado:

    ‘forcing’ and ‘causative’ are not at all the same thing; ‘forcings’ apply to models only, as externally set variables; the ‘feedbacks’ (the internal variables that change as the model does calculations, such as upper atmospheric water vapor) are quite causative

    So what words would you use instead of “forcings” and “feedbacks” when talking to a non-scientifically-literate layman who nevertheless wants to get a very basic understanding of what the climatologists are saying? Mentioning the models simply in order to explain the difference between water vapour and CO2 would turn many of them right off (they’d think if you can’t explain even something that basic about real world climate without having to resort to models, then it must be all smoke and mirrors and nothing to do with the real world. Can you suggest some layman’s language alternative words for “forcing” and “feedback”, or at the least, layman’s definitions for them that don’t involve the models? (Another word I have trouble translating into layman’s English, by the way is “proxy”).

    Dave

  137. Reid:

    And, Eli, the question is whether increasing temperatures can create an unbounded positive feedback of CO2 production resulting in increasing temperatures and more CO2 production essentially ad infinitum (or at least to the point where the whole planet is fried). If so, then there is no explanation for why we have not experienced a runaway greenhouse in the past.

    But, as I have stated, even a bounded positive feedback should produce a limit cycle but, it hasn’t so, it is apparent to me that there is currently a discrepancy between the historical record and what appears to be the prevailing paradigm.

  138. Ray Ladbury:

    #123, Mike Strong. Hmm, why do we think the situation is different the unfortunate case of Professors Wunsch and Landsea. Well try this on for size. Landsea was part of a group of scientists trying to reach a consensus on what conclusions the evidence would support. In the end, the conclusion was too strong for Landsea to support, and he withdrew his support. That was well within his rights and even his responsibility. It’s even fine that he took his disagreement public. The point is that Landsea had an opportunity to review the final document and opt out when he found he didn’t agree. He was not quoted out of context with no opportunity to correct the misrepresentation(as was Professor Wunsch) with the purpose of lending credence to a position he doesn’t support. I’d consider that a rather significant difference.
    To characterize as reprehensible actions like the frauds committed by this director–which are reprehensible–is not an ad hominem attack. To point out that the arguments advanced by so-called skeptics have already been discredited is not an ad hominem attack. And finally, to insist that the scientific consensus be given due consideration over positions held by a tiny minority is not “unfair or unbalanced”.
    Re 129: Nick, this issue has been flogged to horseburger. Basically, there is no reason why CO2 should have lead temperature in the past, since past warming epochs largely had other causes (orbital changes, etc.). As the planet starts to warm, permafrost melts, releasing CO2, CH4, etc. CO2’s solubility decreases with temperature, so the oceans release CO2. This release of ghg extends and intensifies the warming trend already underway, causing it to last, say 6000 years on average (compare that’s nearly 8x that 800 year lag). RealClimate has dealt with this extensively and you can find posts in the archives.

  139. Charles Muller:

    #131

    – Steve, my post mainly deals with radiative forcing comparison for 180/280/380 ppm CO2 increase, not climate response to this radiative forcing (I recall current best estimate of climate sensivity for 2xCO2 as an order of magnitude).

    – I don’t know what you mean exactly by a “non-linear” manner for climate in responding to a forcing. When we compare LGM / mid-Holocene, for example, where are non-linearities and how do they affect the estimate of climate sensitivity to a particular forcing?

    – I “assume” nothing like an instantaneous response – transient climate response to a forcing is not equilibrium climate sensitivity, of course.

    – The temp. increase since 1850 is 0,57-0,95 K (best estimate 0,76 K) according to AR4 SPM. Do we have any 20.000 yrs temp. reconstruction allowing a comparison for similar 155 yrs / T increase?

  140. Hank Roberts:

    >Wunsch letter
    Right-click on the timestamp and “copy link” — it gets you the info you can post as a clickable link that will take people to the posting right here. Better than second- and third-hand copies, which tend to get unreliable.

  141. Hank Roberts:

    Reid, plankton:
    “The aftermath of this rapid, intense and global warming event may be the best example in the geological record of the response of the Earth to high atmospheric carbon dioxide concentrations and high temperatures. This response has been suggested to include an intensified flux of organic carbon from the ocean surface to the deep ocean and its subsequent burial through biogeochemical feedback mechanisms. Here we present firm evidence for this view from two ocean drilling cores …..”

    Global change. Plankton cooled a greenhouse.
    Nature. 2000 Sep 14;407(6801):143-4.
    Erratum in:
    Nature 2000 Sep 28;407(6803):467. (length of warm period has a typo, in the article)
    Comment on:
    Nature. 2000 Sep 14;407(6801):171-4.

  142. Ed Sears:

    re 95 ‘Can anyone point me to work done on plant carbon fixing as a result of an extended growing season in northern land masses?’ Unwashed random

    For the broad picture, try:
    Global Carbon Project (2003) Science Framework and Implementation. Earth System Science Partnership (IGBP, IHDP, WCRP, DIVERSITAS) Report No. 1; Global Carbon Project Report No. 1, 66 pp, Canberra.

    UNESCO-SCOPE (2006). The Global Carbon Cycle. UNESCO-SCOPE Policy Briefs October 2006 – No. 2. UNESCO-SCOPE, Paris.

    Hyvonen, R. et al (2007), ‘The likely impact of elevated [CO2], nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: a literature review’. New Phytologist 173 (3), pp.463â��480.

    Then have a look on google scholar for D.Baldocchi and FLUXNET, P Smith from University of Aberdeen, and Prof Ian Woodward of University of Sheffield.

    As it happens :) I am going in a couple of weeks to a conference held by the NERC Quantifying and Understanding the Earth System programme. The agenda is:
    1: How important are biotic feedbacks for 21st century?
    2: How are climate and atmospheric composition regulated on timescales up to a million years?
    3: How much climate (change) is dangerous?
    4: How much can be avoided by managing the biosphere?
    5: Observing the Earth System (and Earth System Atlas)

    A last point on GGW Swindle: one of the closing remarks referred to Britain’s chief scientist and breeding pairs of humans in Antarctica. The scientist in question is James Lovelock and he talks about the Arctic (rather than Sir David King, the official British Govt Chief Scientific Advisor).

  143. Ike Solem:

    Dave, what I would say is that climate is naturally variable and responds to a wide variety of influences, but that burning fossil fuels has increased the atmospheric CO2 levels to levels not seen in millions of years; this additional CO2 acts as an extra blanket that causes the Earth to warm, on top of any natural variability in climate and weather. The mechanism responsible is absorption and re-radiation of infrared radiation (heat) by atmospheric CO2 and also by methane and other gases including water vapor.

    This warming causes all kinds of secondary effects, like the evaporation of more water into the atmosphere, the melting of ice sheets and permafrost, the drying of continental interiors, changes in precipitation patterns and the warming of the the oceans. More water in the atmosphere means a thicker blanket; melting the ice sheets means that less sunlight is reflected back to space, and so you end up with a significant effect. Based on the physics involved, it seems that the ‘blanket effect’ may have been a better term than the ‘greenhouse effect’.

    There are long-term consequences to doing this – rise in sea level is one, and it may happen faster than we think due to rapid melting of Greenland and Antarctic ice sheets, and there may be significant effects on the circulation of the oceans as well, with all kinds of attendant problems related to ecosystems, agriculture, extreme weather events, and so on. The current scientific debate is not over whether this is happening or not, but rather over how fast will it happen and how far will it go? The largest uncertainty in this seems to be what future human behavior will be over the next century, however – but at the higher end of possibilities, there may be unpleasant surprises, like release of vast amounts of methane to the atmosphere.

    Unfortunately, we can’t do experiments such as doubling the CO2 on one Earth while leaving it at the pre-industrial level on another Earth, so we have to rely on (1) detailed observations of the land, ocean, ice sheets and atmosphere and (2) computer models that attempt to calculate how the climate will change over time due to changes in the atmosphere’s composition. The terms ‘feedbacks’ and ‘forcings’ are scientific model jargon with very specific meanings (internal variables and external variables for a specific model), rather like ‘critical analysis’ which doesn’t mean doing a hatchet job on the subject, but rather carefully looking at all the variables involved (after Carl Wunsch). Water vapor is treated as an internal variable because of the effect of warming the surface on evaporation rates. Does warming the surface also affect the CO2 fluxes? Probably yes.. but that hasn’t been included in the models… and if it was, then you could say that CO2 was a feedback as well as a forcing.

    There’s just no way to put all that into a thirty second soundbite, without talking too fast to be understood.

    As far as a proxy goes, that’s a paleoclimate term that is best translated as indirect evidence. Paleoclimatology is like what a forensics expert does at the scene of a crime – collecting fibers, hairs, mud, etc. in the hope of reconstructing the events that took place. For example, ice cream that’s been frozen and thawed repeatedly looks a lot different from ice cream that’s never thawed, so that serves as a rough proxy for the past temperature of the freezer (big ice crystals are a bad sign). Hope that helps, any corrections or suggestions appreciated.

  144. Mark A. York:

    RE #135 “Forcing” is what CO2 as a molecule does. We add it to the atmosphere by burning carbon based fuels, and it becomes a driving force for greenhouse warming. It doesn’t leave, nor would it be there at this level were we not adding it. Water vapor is just recycled. That’s as basic as it can be.

  145. Reid:

    OK, Hank, so I guess you are saying plankton processes basically form a negative feedback which is more puissant than the positive feedback of CO2 release due to warming. So, what keeps the plankton feedback from working similarly now?

  146. Eli Rabett:

    137 No. Two answers. First, the practical the original earth atmosphere (~4.5 billion years ago) was about 30% CO2 and there was no runaway. Second, the theoretical, an an argument in Atmospheric Chemistry by Richard Wayne pp 58 points out that if the water vapor pressure becomes saturated with respect to ice or liquid any runaway would stop (the water vapor would precipitate cooling everything). This happens at the orbit of the earth a a few mbar water vapor pressure. OTOH, Venus is that much closer to the sun so that the P(T) vapor pressure curve (Clausius Clapyron) never hits the liquid/solid boundary, so it can grow without limit and go into runaway. Venus basically cooked out most of the water early on. Very interesting stuff.

  147. Reid:

    Thank you, Gavin, for responding to #114. But, as you may have seen if you have read my posts, this is a problem that needs careful explication. If there is a positive CO2 feedback that did not lead to instability, and it aparently did not, either of a runaway or limit cycle, then there must be some counterbalance, a negative feedback which is stronger than the positive feedback of the CO2 release. And, this leads to a problem because a negative feedback is inherently stabilizing. As a result, whatever exogenous forcing humankind contributes in the form of production of greenhouse gases is going to be degained by the one plus the feedback gain of this negative feedback, whatever it is, what we feedback engineers refer to as the “Sensitivity Function.”

    Is this negative feedback of plankton sequestration mentioned by Hank accepted by the mainstream of climate scientists? Or, is there some other process which accounts for the fact that the Earth has not already suffered the Venusian fate? Is there a reference which addresses this which I may consult?

    BTW, in this post:

    “”Even in simple systems, small positive feedbacks can lead to stable situations as long as the ‘gain’ factor is less than one”

    This is otherwise known as a negative feedback. In a discretized system, if the feedback gain is g, the discretized feedback gain is exp{g*T} where T is the sample period. This maps the “s-plane” of positive and negative feedbacks to the “z-plane” in which negative feedbacks are mapped to the interior of the unit circle in the complex plane.

    [Response: Please read the linked post again. You can think of negative feedback as a series where each perturbation has an opposing effect i.e. 1-r+r2-r3… and positive feedback where each perturbation is additive 1+r+r2+r3… Negative feedback is always stable (the series converges to 1/(1+r) which is always less than 1), while positive feedback will only converge to 1/(1-r) (> 1) if r is smaller than one. The point is that positive feedbacks are often bounded – which is a good thing. – gavin]

  148. Reid:

    Note, I am focusing on the ice age era in which the lag appears to be confirmed. It only takes one counterexample to invalidate a theory. The idea that a positive feedback of CO2, which is the focus of all the brouhaha, did not lead to an instability of either the bounded or unbounded type, is a circumstance which must be explained.

  149. Steve Bloom:

    Re #139: Charles, the comment numbers shifted afterwards. My comment was in response to what is now #127 by John Lang. I need to remember to add a name on my responses for when this happens.

  150. Ike Solem:

    Regarding the issue of the temperature lag in the glacial-to-interglacial transition, this issue has indeed been discussed at RC. For an overview of the topic see http://geoweb.princeton.edu/people/faculty/sigman/paperpdfs/Sigman00Nature.pdf “Glacial/interglacial variations in atmospheric carbon dioxide, Sigman & Boyle Nature 2000″ (this covers the hypothetical role of the phytoplankton in detail) – the issue addressed is this:

    However, the regularity of the CO2 variations and the consistency of the upper and lower limits of atmospheric CO2 through multiple 100-kyr cycles (Fig. 1) are suggestive of a well ordered set of dominant mechanisms, the `holy grail’ of glacial/interglacial CO2 research.

    An alternative but similar hypothesis (more terrestrial) is that as the interglacial-to-glacial transition sets in, you start getting cold autumns – and microbial respiration of plant matter is generally controlled by temperature. The seesaw pattern in the 20th century Northern hemisphere CO2 record is a result of this seasonal imbalance between spring photosynthesis and fall respiration of dead plant matter. Cold autumns would limit one side of the seesaw, but photosynthesis would still occur in the summer – and over thousands of years, this imbalance would slowly draw down atmospheric CO2. The change in the orbital forcing would help this out – so you would get a buildup of organic carbon in soils and bogs in the latter half of the interglacial.

    At the height of the glacial period, this carbon would remain frozen in the ground an inaccessible. As the orbital solar forcing starts warming things up, this carbon becomes exposed – except now the situation is reversed, and there is suddenly a lot of edible carbon around for microbes to devour, resulting in a net excess of respiration over photosynthesis – thus the relatively rapid rise in CO2. More interesting in terms of this notion is the co-rise of atmospheric methane coming out of the glacial period; where does that methane come from? Wetlands are one possibility (vast herds of ruminants might be another?).

    In any case, we can come up with different hypothesis on this, but they are a lot harder to test. However, rates of photosyntheis and respiration on a yearly basis are on the order of 100 GT carbon/year, compared to the ~6 GT of fossil carbon that humans inject into the atmosphere. Small imbalances in the P/R ratio over thousands of years can easily change the atmospheric CO2 levels. Our use of fossil fuels represents a large imbalance of respiration (of ancient carbon) over photosynthesis.

    In any case, the argument that since CO2 lags behind temperature, CO2 can’t be responsible for temperature changes is not logical. Falling pebbles can trigger an avalanche, but that doesn’t mean that the boulders are not responsible for the net force of the avalanche. One hypothesis for why the avalanche doesn’t run on forever is that photosynthesis comes into balance with respiration at the height of the interglacial. Others are possible – but we know from the ice core record that CO2 peaks at the temperature maximum of the interglacials, and doesn’t continue increasing.

    The current situation is very different from the glacial to interglacial transition. Rates of atmospheric CO2 increase from the burning of fossil fuels are some 30X greater than anything seen in the glacial to interglacial transition – and the climate background is fundamentally different. A slowing of the Atlantic thermohaline circulation due to a less saline North Atlantic should not be expected to cool Europe, for example. Rather, we seem to be rapidly heading into a climate regime similar to those of over 3 million years ago.

  151. Dave Rado:

    Ike and Mark (#143, 144), thanks for your comments. Just to clarify though, it wasn’t me who needed an explanation of how the greenhouse effect works, although Ike’s summary is excellent and I’ll probably use it as a template; but it was that I sometimes have difficulty translating the jargon when I’m trying to explain things to open-minded sceptics who are not scientifically minded, for whom mention of the models except when absolutely necessary is a turn-off. Can I get away with saying “driving force” and “amplifier” instead of “forcing” and “positive feedback” in that context, do you think? And if so, can you think of a layman’s word I could use when talking to such people, instead of “negative feedbacks”?

    Re. proxies, I think the word implies something more specific than “indirect evidence” does. For instance if I say “vineyards are not a good proxy for temperature” it means more and sounds better than “vineyards are not good indirect evidence for temperature” (which sounds like a double negative apart from anything else). Could I perhaps use the word “indicator” as a direct substitute for “proxy”, do you think?

    Dave

  152. Pat Saunders:

    The Great Global Warming Swindle is being shown again this evening (Monday 12 March) at 10:00 pm on More4 and is described on their website http://www.channel4.com/listings/ as a “Polemical film challenging the consensus that man-made CO2 is heating up the earth. Featuring leading academics, the film questions the science behind the accepted reasons for global warming and argues other explanations for climate change are not being properly aired.”

    Perhaps we should be pressing for a disclaimer at its start…

  153. pete best:

    Dear RC

    Are programs like this one and refuting the skeptics along with AGW’s preceived political and economic implications the reason why serious/abrupt (non linear) climate change is absent from the recent IPCC report and literature?

    Here is one example, ice dynamics. It is assumed that Greenland and Antartica are large scale bodies of ice that will take a long time to change in any significant way. However if ice synamics are inherently non linear then rapid non linear collapse of these ice bodies could kick in or play out sooner than thought.

    Another one is peat bogs in siberia (melting permafrost) and other bodies of rotting vegetation that could accelerate rapid change if the temperature rises much more.

    Is climate change actually running faster than projections and models are indicating in any area at all?

  154. DavidH:

    Re #109

    While I feel a little sorry for Carl Wunsch, we should all be a little sceptical not only of what the popular media publishes, but what they say to us in private. Recently, I had an email from a UK broadcaster asking me for an interview. I was concerned that they might just want an ‘Aunt Sally’, and made clear that I was not interested unless there was a clear commitment to balance. An effuse email followed promising balance and a list of the numerous others with views similar to mine who would also contribute. I accepted and put some effort into preparation.

    Before I was to set off to the interview location, I watched Nigel Lawson being interviewed. He described alarmism as the Da Vinci Code of climate research, and poured cold water on the hysteria, to which Sky’s week long ‘Green Britain’ programme was so obviously committed. He was a bit of a killjoy, and I guess and they did not want any more. Soon after, I had a call to say I was no longer needed. So much for a promise of balance. Many alarmists and not even a handful of sceptics in hours of programming.

    But what was Carl Wunsch’s beef? Presumably he would be happy to be the voice of caution on an alarmist programme with all you RealClimate guys? Should factual but inconvenient uncertainties only be presented as footnotes or asides in programmes presenting and stressing the ‘consensus’ hypothesis and declaring the debate over?

    [Response: Not at all. But ‘polemic’ is not a good way to present science since all the usual caveats disappear and you can end up with dishonest programs like this one. I would point you to our discussion of the ‘Global Dimming‘ documentary for our equally trenchant criticism of ‘polemic’ from the other side. Telling it straight should be the guideline (in my opinon) – and that includes showing that there is indeed a consensus on the main issues and the vast amount of data that supports that, but also pointing out the real uncertainties and concerns – not the faux pseudo-debates highlighted here. Maybe that is just not as interesting to some documentary makers. – gavin]

  155. Barton Paul Levenson:

    hopp — you’re a “radical green” who supports nuclear power and doesn’t believe anthropogenic global warming is happening? This must be some strange new definition of “radical green” I never heard before.

  156. Barton Paul Levenson:

    [[Q1: If there is a feedback mechanism, what stops it accelerating exponentially?]]

    It’s a converging series, not a diverging one. The series 1 + 1/2 + 1/4 + 1/8… is an infinite series, but it only sums to 2 no matter how many terms you take into account.

  157. Barton Paul Levenson:

    [[ Holding back emerging economies from developing would certainly condemn another generation to grinding poverty and early death. ]]

    Who wants to “hold back emerging economies from developing?” Are you under the impression that economies can only develop using fossil fuels? Where did you get that idea?

  158. Barton Paul Levenson:

    [[Even Einstein held faith in his special theory in face of growing evidence.]]

    WHAT “growing evidence?” Evidence that relativity isn’t true?

  159. Barton Paul Levenson:

    [[what role could the absolute increase of global water content play, if any? Has this been considered in any way? ]]

    If there is more water vapor in the atmosphere, the surface is hotter, all else being equal, since water vapor is a greenhouse gas. But its short residence time in the atmosphere means it is very difficult to manipulate. We could double the water vapor in the atmosphere tomorrow and the extra would be almost all gone in a month. The thing to watch with water vapor is the temperature — the hotter the world, the more water vapor in the atmosphere, according to the Clausius-Clapeyron law. And of course the water vapor adds more heating, which adds more water vapor, etc. But it’s a converging series.

  160. Barton Paul Levenson:

    [[If there is a positive CO2 feedback that did not lead to instability, and it aparently did not, either of a runaway or limit cycle, then there must be some counterbalance, a negative feedback which is stronger than the positive feedback of the CO2 release. ]]

    That is a non sequitur, and makes me strongly doubt your claim to be familiar with how feedbacks work. Any positive feedback that converges stops all by itself; it doesn’t require a second feedback to counteract it. The math is as simple as a converging series versus a diverging series.

  161. John Lang:

    If CO2 greenhouse warming is not linear, and the first 100 ppm increase in CO2, feedback from, ended the ice age (4.0C to 8C contribution) and the next 100 ppm over the last century added a further 0.8C – isn’t the next 100 ppm going to have a small effect?

    Has temperature already increased about as much as it can?

    190 to 290 ppm – 8.0C
    290 to 384 ppm – 0.8C
    384 to 550 ppm – 0.1C

    It is either that or all the explanations regarding feedback for the interglacial warming and the recent warming do not add up.

  162. tamino:

    Re: #160 John Lang

    As has been made clear many times here, the increase of CO2 is not the only factor warming the planet during deglaciation. So, of the 5 deg.C global warming during a deglaciation, not all 5 are due to CO2. Hence in the “180 to 280″ row the number should be less than 5.

    It’s also been made clear here many times that the planet hasn’t yet responded to all the warming that’s “in the pipeline” from the greenhouse gases we’ve already put up there. Hence in the “280 to 380″ row the number should be greater than 0.8. Based on estimates of climate sensitivity, it should be around 1.4.

    It seems to me that you have a tendency to massage numbers. For example, for deglaciation you say 4 to 8, but I consistently see 5 in the peer-reviewed literature and have never seen more than 6. Then from the “4 to 8″ range, you put 8 in your table. Also, in a previous post (#101) you claimed that adjustments to temperature records increased the trend by 0.5 deg.C — James Hansen and colleagues disagree with you.

  163. Devil's Kitchen:

    [Response: Try and get your head around the idea that two different things can be happening at the same time. One, the ocean and terrestrial carbon cycle is affected by climate. Two, the amount of CO2 in the air affects the greenhouse properties of the atmosphere. Part I is obvious from the paleo-record, Part II is measured in lab experiments and in observations. Together they do a pretty good job at explaining how cold it gets during the ice ages – which are paced by Milankovitch forcings. Without the radiative effect of the GHG changes, the ice ages would not have been so icy. There, that wasn’t so difficult, was it? – gavin]

    Sorry, Gavin, yes it is. I’m sorry, but I’m no climate scientist (microbiology degree but years ago) and it simply isn’t simple.

    Could you please describe, without acronyms or talk of “Milankovitch forcings”, how it is that a temperature rise that leads to higher CO2 in the atmosphere which leads to more warming (an extra 4,200 years, as you say) then collapses into an ice age?

    Surely the world should continue warming, which continues to force CO2 into the atmosphere, which continues to warm, etc.? I can see that you might get increased vegetation growth that might lead to increased CO2 fixing but it doesn’t sound like it should be enough to force such a massive drop in temperature.

    DK

    [Response: I didn’t mean to suggest the ice-age carbon cycle changes were simple. Indeed there is still substantial uncertainty in how the various changes occur. The ‘simple’ idea is that there are two effects: CO2 affecting climate (which is supported by observations, theory and modelling) and a separate effect of climate on CO2 – for which we have observations from the ice cores. The processes by which the climate – CO2 effect works are basically a reduction in terrestrial biomass (which puts CO2 into the atmosphere), an increase in ocean carbon (which takes it out). The process by which the ocean takes up carbon consists of the solubility effect (colder oceans take up more carbon dioxide), and also changes to biology (increased production can lead to more export of carbon to the deep ocean). The biological changes are complicated and will be affected by increased windiness, possibly increased dust flux (as a source of micro-nutrients) and changes to mixed layer depths etc. As you might imagine the biological changes are the least well understood. -gavin]

  164. Barton Paul Levenson:

    Here’s some math on how climate feedbacks work.

    The increase solely from radiative transfer factors, for CO2, is about 1.2 K from doubling (Houghton 2004). This gets multiplied by the “gain” from several feedbacks. Feedbacks are fractions less than 1, and are summed before being inserted in the gain equation:

    G = 1 / (1 – sum(fi))

    Here are the feedback factors used in the GISS (NASA Goddard Institute for Space Studies) and GFDL (Princeton’s Geophysical Fluid Dynamics Laboratory) global climate models c. 1990:

    Process                  GISS     GFDL
    water vapor/lapse rate   0.40     0.43
    cloud                    0.22     0.11
    ice/albedo               0.09     0.16
                             ----     ----
    Total:                   0.71     0.70
    

    So inserted in the gain equation, these factors yield a gain of 3.44 for the GISS model and 3.33 for the GFDL model. This gives a climate sensitivity of 1.2 x 3.44 = 4.1 K for the first model and 4.0 K for the second.

    [Response: Note these are not the factors ‘used’, but the factors derived from the GCMs and will vary (slightly) as the models develop. The current GISS sensitivity is 2.7 deg C. – gavin]

  165. Barton Paul Levenson:

    [[Has temperature already increased about as much as it can?

    190 to 290 ppm – 8.0C
    290 to 384 ppm – 0.8C
    384 to 550 ppm – 0.1C

    It is either that or all the explanations regarding feedback for the interglacial warming and the recent warming do not add up. ]]

    There’s a third choice: You’re applying a relation between CO2 and temperature which ignores all the confounding factors. The ice age warming was overlaid on a warming due to a change in insolation distribution (the Milankovic cycles). The current change was in the face of a big negative aerosol forcing for 1940-1970. And I don’t know where you got the third figure.

  166. Reid:

    The comments left can be really frustrating to someone who is intimately aquainted with these matters, as am I.

    #160 said:
    “[[If there is a positive CO2 feedback that did not lead to instability, and it aparently did not, either of a runaway or limit cycle, then there must be some counterbalance, a negative feedback which is stronger than the positive feedback of the CO2 release. ]]
    That is a non sequitur, and makes me strongly doubt your claim to be familiar with how feedbacks work. Any positive feedback that converges stops all by itself; it doesn’t require a second feedback to counteract it. The math is as simple as a converging series versus a diverging series. ”

    Yes it does. This is fundamental to how limit cycles work. Let’s take the equation

    xdot = a*x

    where “a” is a gain which decreases in time. The solution is x = x(0)*exp(integral(a*dt)). At time T, “a” goes to zero. Let A(T,0) = exp(integral(a*dt)) from zero to T. Now, the state is at x(T) = A(T,0)*x(0) > x(0). What pulls x(T) back down to x(0)?

    In a limit cycle, an instability tends to pull the system to its limits where the instability vanishes and negative feedbacks pull it back down again, at which time the instability reasserts itself and pushes it back up again. A time lag between the time the instabillty vanishes and reasserts itself allows a cycle to be established. This is so fundamental and elementary, I am embarrassed on your behalf for making the comment.

    Gavin wrote:

    “[Response: Please read the linked post again. You can think of negative feedback as a series where each perturbation has an opposing effect i.e. 1-r+r2-r3… and positive feedback where each perturbation is additive 1+r+r2+r3… Negative feedback is always stable (the series converges to 1/(1+r) which is always less than 1), while positive feedback will only converge to 1/(1-r) (> 1) if r is smaller than one. The point is that positive feedbacks are often bounded – which is a good thing. – gavin]”

    No, that is not how this stuff comes about. Positive and negative feedbacks are couched in terms of continuous time systems. In the difeq above, if “a” is positive, it is a positive feedback. If “a” is negative, it is a negative feedback. There is no positive/negative divide in discrete time systems. I can have
    x(k+1) = -2*x(k)
    where “k” is the index. Each term in the series has an opposing, negative effect, but the series is divergent. Similarly, I can have
    x(k+1) = 0.5*x(k)
    The the gain is positive, yet this series is convergent. If you have a system described by the difeq above, then at discrete instants t(k), the solution is
    x(t(k+1)) = A(t(k+1),t(k))*x(t(k))
    If the continuous time gain “a” is a negative feedback, then A(t(k+1),t(k)) has magnitude less than one, and the system is stable. If it is positive, A(t(k+1),t(k)) has magnitude greater than one, and the system is unstable. This is why stable discrete time systems are seen to map the left half of the complex plane, the region of negative feedbacks for continuous time systems, into the unit circle, the region of stability for discrete time systems. This is how the entire nomenclature of “positive” and “negative” feedbacks came to be.
    Do you climate guys work with people versed in stability theory, or are you just winging it? This is all very, very elementary stuff. I think you need to get some such people in your working group because it is becoming apparent to me that there are some very thorny issues here which are not being properly taken account of.

    [Response: You are not solving the appropriate equation. I recommend Hansen et al 1984 for an explanation and definition of terms that is better than I can squeeze in here. – gavin]

    [Response:AFAIK, people don’t know exactly why CO2 stopped at 280 in interglacials and 180 in glacials. It doesn’t have to be feedbacks: there could simply be some reservoir that is exhausted. Also, thats for the previous 4 interglacials: before then, EPICA shows 250. This again is unexplained – William]

  167. Reid:

    Gavin – it makes no sense to talk of “negative” and “positive” feedbacks for discrete systems without analogy to continuous systems because the criterion for stability in discrete time systems is “gain magnitude less than unity”. As you can easily see in my example above, it is possible to have a negative gain in a discrete time system and yet have instability. The dividing point is unity gain, not positive/negative. If you guys have reinvented the wheel and come up with a new nomenclature all your own, then you have a vast archive of knowledge to reinterpret.

    William – it does not matter if the CO2 petered out. Upon cooling, it should have been reabsorbed, then re-released to warm things up again in a classic limit cycle. That it did not is an important clue you guys should be using to further your understanding of the phenomenon.

  168. hopp:

    So you comment on a post that was censored? Yes, I am a green. And I try to think like a tree. With several branches, and falling leaves. Non-linear, several competing variations, complex, with doubt, self-criticism and uncertainty.

    It’s only a healthy approach, because, behind the surface, most of our so called knowledge is about trusting others/authorities/sources. Who/what do you trust? And why?
    I have professional interest in AGW from such a perspective, and at the same time I’m a green. No problem. You can be many things. Don’t be a grey, one-coloured, dull rock with your book burning antics and holocaust comparisons.

    I do know that I made valid points about the interpretation process. I’d like to see the AGW process naked, without the political load. When you read about the research on AGW you are all the time faced with speculation, interpretation, probabilities. As a philosopher I do know that these do not go hand in hand with such absolute certainty. By preaching to people like some religious fanatics who are always right, always have the answers, always sound so 100% certain (look in the mirror gavin) you are turning people off.

  169. Darren Wild:

    I watched the Channel 4 programme last week and again this weekend. I was amazed with its apparent lack of balance. However it also amazes me that the argument for the existence of man made global warming, also seems to have the same lack of balance.

    I am a complete ignoramus when it comes to science generally; however what I know is that evangelists of any kind turn me off, this issue seem to attract evangelists.

    When the politicians get involved, as they have, then the outcomes will only revolve around egos and money anyway. In the end itâ??s the lies and misinformation that will determine our fate both way.

    What the Channel 4 programme was successful at doing was to continue the debate, besides what’s wrong with an alternative view. Even if it does have flaws, show me theories that don’t. Misinformation may cause confusion but the whole thing confuses me anyway. If nothing else surly it must demonstrate a need for the “community” to work harder to convince the sceptics, on both sides of the argument.

    C4 moved me to look for more information, which lead me to this blog. However reading through the previous 160+ posts I’m still none the wiser. I appreciate this is a complex issue, and far beyond the scope of my intelligence. However I’d like the complex to be made simpler, but not too simple that it misses the point and not sensationalised to the point of incredibility.

    It’s hard not to be cynical about people’s motives on both sides of the argument. I can’t help but feel either way it will cost me more in taxes.

  170. James:

    Re #167: […it does not matter if the CO2 petered out. Upon cooling, it should have been reabsorbed, then re-released to warm things up again in a classic limit cycle.]

    Err… Isn’t that basically what the ice cores and so on show? The planet warms for some reason (most likely Milankovic cycles), that causes some CO2 to come out of its reservoir into the atmosphere, which causes further warming, which continues until the resevoir reaches a new equilibrium. Then something causes enough cooling to push CO2 from atmosphere to reservoir, causing more cooling, which continues until the reservoir is full. But the reservoir has a long time constant…

  171. Julian Flood:

    Re 27: thanks for your blog — the link to the Nature article about warming when the planes stopped flying on 11/9 would be even more knock-down if I could actually read Nature without paying — maybe you could make a brief precis.

    How do the climate models stand on contrails? If you take the contrails out from the models which are currently most successful at matching reality, do they respond as the real climate did? It seems this ‘experiment’ can be used to validate the way models match the real world.

    Something else on your site got me the answers (RealClimate article on 22 Dec 2004) to a question that’s puzzled me for ages — how we know that the extra CO2 in the atmosphere is anthropogenic. The first way, isotopes, is a bit worrying as I can think of three ways to disturb the isotope concentrations without invoking humanity at all. The bit that can be summed up as ‘we’ve knocked out a lot so it must be our fault’ suggests a wonderful prelapsarian state of balance which doesn’t sound like nature to me at all, but gives me lots of lovely figures to play around with.

    JF

  172. Steve Bloom:

    Re #169 (Darren): The Discovery of Global Warming on-line book linked in the right bar is the best way to put the current discussion in perspective. IMHO understanding this stuff doesn’t require great intelligence, but it does require some time spent.

  173. Jeffrey Davis:

    What was the source for the aerosol forcing (1940-1970)?

    What dissipated it? (i.e. why is it still not there?)

    [Response: Industrial activity – mainly power stations and transportation. They haven’t dissipated, though sulphates were reduced in most developed countries through Clean Air Acts in the 1970’s. Aerosols are still a big player, but since they don’t accumulate in the atmosphere like CO2, they don’t grow as fast. – gavin]

  174. ferrand stobart:

    What these folk from The Scientific Alliance forget is that while the physical effects of more Carbon Dioxide in the atmosphere – i.e Global Warming – may be disputed, the Physiological and Chemical effects are much more certain. Mankind has altered the air we all breathe, Carbon Dioxide is an acid gas, and it is well attested that the Environment is getting more acid – this may well encourage Virus activity, as this life form prefers more acid conditions. The ‘Flu virus especially being very “pH sensitive”.
    Carbon Dioxide is also a stimulant, and is so used in resuscitation apparatus in hospitals. Viewing the way the World is running about like a f*rt in a colander makes one wonder if we are all being over stimulated ?
    See the Royal Societies work on effects on the oceans: http://www.royalsoc.ac.uk/news.asp?id=3250
    and http://www.bbc.co.uk/dna/actionnetwork/A11109133
    BUT
    If Nature is intent on removing the “Biological Plague” of Mankind and it’s beasts, through disease, and the other “three horsemen”, then those denying that anything untoward is happening in the atmosphere are helping to ensure that Nature is not hindered overmuch in what it intends to do ?

  175. ruidh:

    Can someone address what seems to me to be the obvious objection to the length of the solar cycles-temperature anomaly graph? It doesn’t make sense. What possible connection can there be between these two quantities? The graph makes it worse by connecting the dots with sloped lines that seem to match up with the temperature data. But how can you interpret these lines? Do they represent the average rate of change of the solar cycle length between that cycle and the next? What does that quantity mean?

    Please correct me if I’m wrong, but the solar cycle is the length of time from sunspot minimum to sunspot minimum. Is that span of time correlated with sunspot activity? Are there more or less sunspots per unit time in a (marginally) shorter cycle than in a (marginally) longer one? Or is the length mostly independent from the intensity of the cycle? Does this quantity even make sense as a proxy for “solar activity”? Where do you place the “length” of a given period on the time scale? Does the “length” occur at the beginning, middle or end of the period? Or do you line it up so that it best matches the temperature anomaly (presented in a completely different units of a separate y scale!) to “make your point”?

    Will someone please page Edward Tufte? Cycle lengths represent spans of time with a distinct beginning and end. Why not plot that data?. I could see someone taking a temperature graph versus time and indicating each cycle as a series of vertical bands indication at what point in time each cycle began and ended. Perhaps varying the shading within each band (low = red for heating v. high = blue for cooling) as the number of sunspots *instantaneously* increases and decreases. Perhaps that might illustrate something — numbers accumulated over the same intervals compare better. If the hypothesis is true, we would see heating when sunspot numbers were low and cooling when they were high. But the graph as presented just seems nonsensical to me and intended to fool people who are easily impressed by statistics.

    Am I way off base here?

    [Response: Not at all! These are exactly the objections that were raised at the time. However, the desire of the propagators of to show a good correlation to something solar-related overwhelmed their interest in presenting a balanced case. Especially when it was subsequently shown that the smoothing applied varied towards the end with the sole purpose of providing a better fit to the data (See Laut (2003), Damon and Laut (2004)). -gavin]

  176. Bruce G Frykman:

    “Swindled” was almost certainly “unbalanced” in its opinion of the global warming industry. Of course what I hear literally on a daily basis from BBC, NPR and other major media outlets hardly represents a paragon of balance either. Sometimes this science is presented in a manner that would do Leni Riefenstahl proud. In our era I can think of no more unlikely candidates than Mr Gore his cohorts of Beverly Hill’s illuminati to popularize this “dispassionate” search for truth.

    I find it unfortunate that I have to remind people who purport to speak for science that motives really don’t matter. I certainly would not attribute any bias on your part with the fact that all of you would be out looking for a private sector job with vastly diminished stature and income if the global warming threat isn’t even a tempest of the teapot variety. Science isn’t concerned with the motives of its spokespeople which more properly belong in the religious and political spheres. I would be prepared to listen to ALL of your arguments in publically open debate. If the lay public aren’t smart enough to figure it all out then democracy and human freedom must take a backseat to this purported exigent threat to the planet.

    Therefore, the issue is not whether the editors of “swindled” misrepresented its goals to Carl Wunsch but whether Carl Wunch’s interviewed statements were meritorious.

    It appears to me that what one “believes” in the larger sense is more of a religious test than a scientific test. I don’t care if Carl Wunch believes in global warming or the virgin birth. Were his own words accurately represented in the context that they were presented?

    Further, would it be possible that appearing in such a film could be career damaging; perhaps a perfunctory denial might then be well considered.

    [Response: Carl Wunsch’s career is extremely secure – his comments were made in a particular context – they were used in another to support to position he doesn’t hold. That is misrepresentation, and I think it’s understandable he’s upset. – gavin]

  177. David B. Benson:

    Off-topic, but germane to yesterday’s discussion of the warming from LGM, feedback, etc:

    I found almost all of the postings, and all of the replies by Gavin and William, on these matters quite helpful. Thanks to all!

    With regard to the increase in methane during this warming, last month’s issue of Scientific American has a provocative article on methane emission by living plants. If confirmed, this would explain the observed methane concentrations in the air above tropical rain forests.

    [Response: See Scientists Baffled! – gavin]

  178. Reid:

    #170 James – You are asking the right questions. What causes the CO2 reabsorption and, how long does it take for it to be ready to be re-released? If CO2 release happens progressively with rising temperatures, why should it be reabsorbed at the same temperatures just because they are moving in the opposite direction? What prevents it from being re-released almost as soon as it is reabsorbed?

    I could maybe see a big burp of CO2 from mass extinction of plant and animal life in a great heat wave that would then be reabsorbed as species recovered. But, the time constant of that process should be fairly fast and, I’m not aware of any correlation between CO2 concentrations and mass extinctions. If it were an oceans process, why again would it be any different with the temperature coming down than it was with it going up?

  179. Joe Rosenfels:

    RE: Temperature leads CO2 by 800 years in the ice cores

    quote: ‘From studying all the available data (not just ice cores), the probable sequence of events at a termination goes something like this. Some (currently unknown) process causes Antarctica and the surrounding ocean to warm. This process also causes CO2 to start rising, about 800 years later. Then CO2 further warms the whole planet, because of its heat-trapping properties. This leads to even further CO2 release. So CO2 during ice ages should be thought of as a “feedback”, much like the feedback that results from putting a microphone too near to a loudspeaker.

    In other words, CO2 does not initiate the warmings, but acts as an amplifier once they are underway. From model estimates, CO2 (along with other greenhouse gases CH4 and N2O) causes about half of the full glacial-to-interglacial warming.’

    This is where GW falls apart for me, The process that starts the temperature rise is, as above, not understood. At best the C02 is a feedback, so what we are saying is: If we just add c02, without the event that starts the temperature rise, we will get global warming.

    While it is worthwhile to look into the past, those scenarios don’t apply to now, so perhaps we should of never quoted the ice cores etc

  180. David B. Benson:

    Re #178, etc. — My rough-n-ready calculation suggests that the increase in atmospheric carbon dioxide concentration during the melting of the LGM ice does not suffice to explain the approximately 6 K warming. I suggest also methane concentrations and albedo effects?

    Tziperman, et al., fully referenced in the comments of the ice age trigger thread, have a simple model of glacial-interglracial cycling in which so-called greenhouse gases does not appear: When sufficiently cold, enough sea ice forms to shut off snowfall onto ice sheets. Then the ice sheets shrink until enough sea ice melts, at which time the ice sheets reform. This non-linear model, tuned for orbital forcing, does quite well for the last 900 ky.

  181. W. Earl Allen:

    In a way, science works like markets–some buyers are willing to pay too much or too little, just as some sellers have unreasonable expectations. Ultimately, though a price is agreed and those willing to sell and buy can do so. It is the best method we’ve come up with to determine a “fair” price.”

    Yes. But when the market is horrendously distorted by coercively-financed science, then what gets paid for is science that proves what those who want to coerce more money out of taxpayers want to have proved. If you prove that what is happening can only be solved by coercively destroying the free markets that have created the greatest improvements in the quality of human life, then you’re probably proposing a solution that can, at best, be called “evil.”

    I would be tremendously more impressed by the science presented on RealClimate were it not, in the main, coercively funded. Surely there are green philanthropists out there who could finance this science without the stigma of its funding having been coerced from the pockets of taxpayers by governments.

    Because the vast majority of CAGW science is politically funded, it will, inevitably, be political science, disclaimers on this site notwithstanding. Until all the scientists who post on RealClimate voluntarily renounce their coercive financing and ask for funding from individuals (perhaps a $2000/per limit, like the politicians have imposed, might be fair) I will be absolutely convinced that their science is political, not factual, not evidential.

  182. Marcus:

    #178: Reid, if I understand your question right, then one simplified version of the science might answer it:

    Imagine a world at T=260K, CO2=180 ppm, with ocean and atmosphere at equilibrium. Now, change the orbital cycle such that additional forcing leads to a direct T increase of 2K. At 262K, the ocean’s ability to hold carbon decreases. Therefore, it releases CO2. CO2 concentrations rise to 200 ppm.

    This increase in CO2 leads to additional warming. T rises to 263K. The increase in temperature leads to an additional CO2 rise, to 210 ppm. This temperature rise leads to more CO2, which leads to more temperature. As long as the series is convergent, you don’t have runaway. To make this easy, let’s say that the final equilibrium state is 264K, and 220 ppm.

    Now, new orbital changes lead to direct cooling of 2K. Well, at 262K, we already established that the CO2 equilibrium between atmosphere and ocean would be at 200 ppm. Therefore, the ocean will reabsorb CO2 to reach 200ppm. This will lead to further cooling, which will lead to more CO2 reabsorbed. Until eventually a new equilibrium is reached – or rather, the old equilibrium at T=260K, CO2=180ppm.

    This very very simplified model should demonstrate why it seems like the direction of temperature movement matters. “Seems”, because the actual key difference is the orbital parameter: in one case, at 262K and 200ppm the net forcing is positive. In the other, at 262K and 200ppm, the net forcing is negative.

    Mind you, with hysterisis effects, you can get results where the direction of temperature change actually does matter, but you don’t need such effects to create a hypothetical system that can have glacial and interglacial states where a CO2 feedback is important in determining the temperature of said states.

    (In fact, looking at more of your comments, I think that you are not understanding the role of this external forcing. Maybe this is why you and Gavin are talking at cross-purposes about limit cycles etc.)

  183. Anthony Carter:

    It may seem a simple question, but please indulge me. I may ask these questions from time to time just to get to grips with some of the arguments.

    If greenhouse gases trap heat from IR, do they also reflect some back? If this is so, is there not a balancing of the two i.e. as the greenhous gases increase the reflection of IR increases, therefore negating the heating effect of greehouse gases?

    I am not a skeptic, but I am wavering, as I am sure a lot of people are, especially being rail-roaded down a particular path by a government whom never seem to get the facts right and often mis-represents them(Iraq’s non-existent WMD’s being one). My philosophy at the moment is to err on the side of caution, and in all honesty the UK is becoming a dirty smelly place, so any reduction in the pollutants is a good thing rather than a bad thing.

  184. Reid:

    #170 James – I should have pointed out, though, that this statement appears contradictory, in that it implies that the CO2 has become a negative feedback that pushes itself back into the reservoir:

    “Then something causes enough cooling to push CO2 from atmosphere to reservoir, causing more cooling, which continues until the reservoir is full.”

    CO2 is always a positive feedback. It will always fight whatever is trying to push the temperature down. If the force pushing the temperature down lets up, the CO2 will immediately start pushing upwards again.

    And, that brings me to #179 Joe – Actually, a positive feedback is self-sustaining so, this could theoretically happen. The only plausible scenarios I see are either: 1) CO2 is not a dominant feedback or 2) we are already experiencing a very complex limit cycle which just happens to be limited to a level and a frequency that allows life to exist on the Earth.

  185. Reid:

    #182 Marcus:

    “Now, new orbital changes lead to direct cooling of 2K. Well, at 262K, we already established that the CO2 equilibrium between atmosphere and ocean would be at 200 ppm. Therefore, the ocean will reabsorb CO2 to reach 200ppm. This will lead to further cooling, which will lead to more CO2 reabsorbed. Until eventually a new equilibrium is reached – or rather, the old equilibrium at T=260K, CO2=180ppm. “

    Marcus, I’m sorry but, you have made the same mistake as James and converted a positive feedback into a negative one. You have already established that a 200 ppm CO2 concentration in the absence of a forcing will result in a temperature increase to 263K. The CO2 effect is only self-sustaining in the upward direction. To get the temperature down, you have to keep forcing it and, as soon as the force lets up, you will start rising again. That is how a positive feedback works.

  186. David B. Benson:

    Re #184 & #185: Reid — You need to learn about ocean temperature and the effect this has on the balance between atmospheric and deep ocean carbon.

    But your point about a complex limit cycle is well taken, IMHO.

  187. Reid:

    #186 David – I need to learn about all sorts of things, and I want to learn others and these two sets only intersect about halfway.:)

    I take it you mean that this is a mechanism for limiting the amount of CO2 that can be naturally released into the atmosphere? If so, it does not appear to occur to William in his response to #166.

    But, fine, let the CO2 be limited. There is still this nagging problem of how do you get the CO2 back into the reservoir once it has been released and biased the temperatures upwards?

  188. Marcus:

    Reid, I’m sorry, but you apparently don’t understand what “positive feedback” means in the climate context, and perhaps this is the key to your confusion. A positive feedback _amplifies_ an external forcing. A negative feedback dampens an external forcing. The _direction_ of said external forcing is not an issue.

    So in my example, an external forcing moves us to 262K. In the first case, CO2 is at 180 ppm, the temperature is at 262K. An increase in CO2 (to 200ppm) leads to more forcing, therefore more temperature rise.

    In the second case, CO2 is at 220 ppm, and the temperature is at 262K. In order to reach 200 ppm, CO2 concentrations decrease. This leads to less forcing, therefore less temperature.

    Think about it. Perhaps try creating a simple spreadsheet model with ocean CO2, atmospheric CO2, an external forcing, and a temperature. If Temp = atm.CO2 + external forcing, OceanCO2 = Aconstant/temp(lag one), and AtmCO2 = Bconstant – OceanCO2, then you have a simple model with positive feedback. Choose your constants so you start in equilibrium (you can always just “run” your model for several periods to find equilibrium). Then increase your external forcing in a step function. There will be an instantaneous temperature change, followed by several periods where atmCO2 and T continue to increase, in ever smaller amounts, approaching a new equilibrium. Decrease your external forcing to its original value, and there will be an instantaneous temp. decrease, followed by atmCO2 and T decreasing back to the first equilibrium.

    Then play with your new model to understand its behavior. Try setting the oceanCO2 to be equal to temperature over a constant to see a negative feedback, and damping behavior. Perhaps try an set up a oceanCO2 model that depends on the difference between the previous period atm. and ocean CO2 to determine how fast CO2 enters/exits the system (but still with a dependence on temperature for the equilibrium CO2 level). Or model human CO2 changes by changing the Bconstant in the atmCO2 equation. Its fun! Try it. And you might even learn something despite it being a really, really simple system. =)

  189. Marcus:

    #183 Anthony: A key point here is that the wavelength of incoming light and outgoing light are different. Incoming light is high energy (visible, UV, etc.) and is absorbed by the ground. The ground is heated, and emits radiation at lower frequencies (eg, IR).

    If you want to get an approximation for the distribution of frequencies, look up “blackbody temperature”, “Planck”, “sun” and “earth” and you’ll probably find webpages devoted to the subject.

    However, this isn’t the whole story. For example, black carbon particles which absorb at all wavelengths also serve to heat the earth up. This is because the earth’s albedo non-zero, so black carbon can heat things up by absorbing light that would otherwise have passed through the atmosphere and bounced off a light surface (like ice, or desert) and left the atmosphere without ever interacting with anything…

  190. James:

    Re #176: […all of you would be out looking for a private sector job with vastly diminished stature and income…]

    You know, before advancing that argument you should really check into the comparative pay rates of the private sector vs academia, especially for those with high-level computer modelling experience. I can’t speak to stature, but I would bet that any of the climate scientists here could get a substantial salary increase, plus nice stock options (which you don’t get in academia), by moving to the private sector.

  191. Hank Roberts:

    Reid, plankton. Plenty of info you can find by searching.

    Here, for example:
    http://www.realclimate.org/index.php?p=134

    Google, for example:
    http://www.es.ucsc.edu/~silab/biocomplex/activities/BIOPEI_report.pdf

    That’s not the same plankton we have now, evolution’s changed the planet a bit since then.

  192. James:

    Re #184: [CO2 is always a positive feedback. It will always fight whatever is trying to push the temperature down. If the force pushing the temperature down lets up, the CO2 will immediately start pushing upwards again.]

    Not necessarily: I think the key word there is “immediately”. Suppose for instance, that the reservoir is the deep ocean. IIRC, it takes several hundred years for water to make a complete circuit from surface to bottom. (Perhaps someone can provide a better number?) So if the system has stabilized in its warm phase, when a cooling starts, some CO2 will go from atmosphere to surface waters. Some of the surface water (especially the cooler bits) in turn will go into the deep ocean, where it won’t immediately be available to return to the atmosphere in a short warming.

    I’m sure reality holds many more complications, but just this simple model gives us a system with two climate states. A large enough external stimulus switches it between states, where it tends to stay until disturbed again.

    Also, may I ask you once again to remember that understanding these past climate cycles is not the same as understanding AGW? In the past (at least the last 50 million years of it, since the PETM), the total amount of CO2 in the system changed very slowly. Now humans have increased the CO2 significantly, in a time so short as to be almost instantaneous in geological terms. We’ve taken a smoothly running system and given it a swift kick: is it going to keep on working as before, do something different (which we may not like), or break down completely?

  193. James:

    Re #181: [But when the market is horrendously distorted by coercively-financed science, then what gets paid for is science that proves what those who want to coerce more money out of taxpayers want to have proved.]

    Fine. Except you’re going to have a real hard time finding someone in the US government (or any other, I think) who actually wants to have global warming proved. Seems to me, in fact, that the current administration has been working pretty hard at denial.

    Or even beyond that: why don’t you come up with a few examples of people who actually want AGW? Outside of e.g. religious nuts looking for the Millenium, I don’t think you’ll have much luck.

    [If you prove that what is happening can only be solved by coercively destroying the free markets…]

    Now where has anyone (other than a few who came in with a pre-existing anti-market bias) suggested that? If you’ll bother to read some of the past discussions related to possible solutions, you’ll find a lot of people pushing market-based approaches. Indeed, you’ll even find some (me, for one) who argue that the fact that fossil fuel users have been exempted from market activity (through being allowed to dump their waste into the commons, without charge) is a significant part of the problem.

  194. Reid:

    owwwwwwwwwww, this hurts… No, no, Marcus. You are making an argument that the feedback is dependent on rate. You are going to have to defend it, if you want to carry on.

    Why should the rate of CO2 release be dependent not just on the magnitude of temperature but on its rate of increase or decrease, or more to the point, on its direction of rate of increase or decrease?

    Dude… Think… CO2 can trap heat. It cannot reflect it out to space. It cannot funnel it through a wormhole to another region of space or even another universe. CO2 does not dissipate heat. What you are claiming is fanciful, to say the least.

  195. Reid:

    Marcus – CO2 can only trap heat. What mechanism are you proposing for it to dissipate it?

  196. Reid:

    And Marcus, please believe me, if I didn’t know the difference between positive and negative feedback, you would know it. My systems would be falling on your head. A little respect, if you please, whippersnapper. If there appears to be a misunderstanding, it is not on my side. Start from there and, you may learn something.

  197. Reid:

    # 192 James – If there is an existent atmospheric CO2 concentration, does it, independently of other variables, act to increase or decrease temperature? If the forcing has stopped, and there is still CO2 in the atmosphere, will it trap heat or send it out to space? Will it do this immediately, or will it wait a little while inquiries are made as to the state of ocean circulation? What mail service does the CO2 use?

    I think what you mean is, will it immediately rebound to its maximum level? But, that is not what I claimed.

  198. Richard Jones:

    I am interested to read all the comments. I enjoyed the entertainment programme, and was disappointed to find that at least one fact presented cannot be verified (I checked the lit. on volcanic CO2). Makes all the rest of the science up for question as well.

    But I didn’t find any answer in RC to a couple of important question raised – how many actual practising scientists are in the 2500 IPCC “consensus”? How many have resigned in the manner of the malaria expert, or asked to have their names removed as contributors?

    If I missed the information I apologise.

  199. Reid:

    Marcus:

    “In order to reach 200 ppm, CO2 concentrations decrease. ”

    It doesn’t matter. At 200 ppm, CO2 traps enough heat to cause a rise in temperature. You said so yourself, on the way up. But somehow, you have convinced yourself that it expels heat when the temperature is decreasing. No. CO2 captures heat. It does not capture cold. It cannot work in the way you specify. CO2 will not reinforce a downward trend. It will only, reluctantly, give up heat and smooth a downward trend. This is how positive feedbacks work.

    Please think this over and, if you have something more to say, do not couch it in terms like “You do not understand”. If you want to deal with me, have some respect for a guy who has labored in the trenches for decades. You can say “I don’t think I made myself clear” or similar but, the notion that I do not understand feedback systems is something you need to disabuse yourself of tout de suite.

  200. Reid:

    #191 Hank: I responded earlier. If this negative feedback is stronger than the positive feedback of CO2, why would it not be working now? Why would it not absorb the CO2 being produced? Will you claim it just has a slow time constant? If so, and if the cumulative effect is exponential, then aren’t we really at worst looking at a temporary interval of warming to be followed by a return to historical norms ro close to them?

  201. Reid:

    James asked:

    “Also, may I ask you once again to remember that understanding these past climate cycles is not the same as understanding AGW? In the past (at least the last 50 million years of it, since the PETM), the total amount of CO2 in the system changed very slowly. Now humans have increased the CO2 significantly, in a time so short as to be almost instantaneous in geological terms. We’ve taken a smoothly running system and given it a swift kick: is it going to keep on working as before, do something different (which we may not like), or break down completely? “

    Quite so. But the potential existence of stabilizing feedbacks which have apparently re-balanced the system in eons past has a direct bearing on whether the exogenous forcing of the system through the introduction of CO2 into the atmosphere will have a significant effect on the Earth’s climate or not.

  202. Ike Solem:

    Reid, consider another climate feedback in the real world, the albedo effect. On one hand albedo can act as a cooling influence – if more snow falls and stays on the ground in the Northern hemisphere, then the albedo change acts as a postive feedback on an initial cooling signal by reflecting more sunlight back to space; if less snow falls, or snow melts (exposing bare ground) then the albedo change acts as a positive feedback on an initial warming signal. So, why don’t small changes in albedo immediately lead to rapid global warming or rapid global cooling? Well, because there are other factors at play, though albedo seems to play a large role in Northern hemisphere climate variability.

    You also say that “CO2 can only trap heat” – but a blanket traps heat, and also dissipates heat (otherwise, you’d go on warming up forever) – but the blanket creates a layer of warm air near the surface. Imagine looking at someone through an infrared viewer who suddenly wrapped a blanket around themselves – eventually, the outer surface of the blanket would radiate as much energy as person initially did, but perhaps at a longer wavelength. Similarly, CO2 also both absorbs and radiates infrared radiation. This can be detected from space; see http://www.nature.com/nature/journal/v410/n6826/abs/410355a0.html for a 2001 discussion.

    It seems that the main issue you are ignoring is that many different feedbacks operate concurrently to affect the climate – and you’re also ignoring the fact that adding massive amounts of fossil fuel carbon to the system changes things quite a bit.

    So, let’s consider the current situation – we add CO2 (or some other infrared absorbing/emitting gas) to the atmosphere of the planet, and we get surface warming, which warms the oceans and the land masses. However, it takes a long time to for the oceans to absorb the extra warmth and to equilibrate with the new atmospheric level of CO2 (which is why we expect the sea level to continue to rise for hundreds of years after CO2 levels are stabilized). However, due to the carbonate buffering system ( http://www.aip.org/history/climate/Revelle.htm ), the oceans don’t simply absorb all the CO2. Likewise, since in our time photosynthesis and respiration appear to be balanced, the biosphere doesn’t absorb the CO2 either – and this was confirmed by Charles Keeling and his measurements of atmospheric CO2 increases since 1958.

    Let’s take another feedback effect that operates concurrently – the water vapor feedback effect due to increased net evaporation – you can also ask, why doesn’t the water vapor keep increasing forever? What removes the water vapor from the atmosphere? (precipitation). Similarly, we can ask what removes CO2 from the atmosphere ? (photosyntheis is one factor) What puts CO2 into the atmosphere? (respiration is one factor). These factors are dependent on other factors – such as nutrient supply and temperature. A good discussion of past CO2 levels relative to today is available at http://news.mongabay.com/2005/1124-climate.html – notice the stability over the 1000 yrs preceding 1750.

    To summarize, the various feedbacks are far more complicated than you are assuming they are, and they interact with one another. Take population growth, as another example – you can say that population growth is always a positive feedback, since more individuals have more offspring, and so on – but population growth can also create a strong negative feedback, as when a population overshoots the carrying capacity of its ecosystem, at which point it severely crashes – due to additional factors.

  203. Reid:

    Marcus: looked at your system. It does not always have an equilibrium, depending on how you choose the parameters. When you choose them right, you have a globally stable equilibrium point and, you are not getting a positive feedback system in the sense of an unstable, self-sustaining system (i.e., in the only sense that matters).

    Please read the above discussion points with Gavin. Positive/negative means nothing in terms of stability applied to discrete time gains. In your system, the system perturbation matrix about the equilibrium is

    Phi = [0 0 1 ; -Aconstant/temp(equilibrium)^2 0 0 ; 0 -1 0]

    where semicolons separate the rows. The eigenvalues of this matrix all have magnitude less than unity at the equilibrium point, when it exists, i.e., this is what everybody on the planet other than climate scientists, apparently, would analogize to a “negative feedback” system.

    My intemperate criticism in previous comments still stands. In this simple system, the temperature is directly proportional to the CO2 concentration but, I would expect the real physics to dictate that the rate of heat accumulation includes a term which is proportional to the CO2 concentration and the temperature is proportional to that. Since CO2 cannot dissipate the heat, it cannot have a stabilizing influence on its own.

  204. Steve Bloom:

    Re #198: Reid, the simple answer is that the glacial cycles are triggered by high-latitude insolation changes that determine whether there is enough summer melting to overcome winter accumulation and thus result in a net increase or decrease of snow. Starting with a change in albedo, this process leads to a complex of feedbacks (prominently including CO2 changes) that ultimately have the effect that is apparent in the ice core record. Deglaciations are much quicker since ice melting is a “wet” process whereas ice accumulation can only occur relatively slowly. Your point about historical norms is useful, but note that the Pleistocene is normal only from the myopic standpoint of human lifetimes.

  205. Hank Roberts:

    Reid, you’re talking theory, I’m talking observations.
    Plankton cooled the PETM greenhouse.

    Evolution responds to climate change, yes, but not overnight.

    Haptophytes (e.g. Emiliania): Common, ecologically important algae
    with a red secondary plastid. Many haptophytes are covered in elaborate
    calcareous scales called coccoliths, which are a primary component of
    chalk sediments such as the white cliffs of Dover.
    Search

    This time around, we have a different kind of plankton — shell-forming, using CO2 to make calcite and aragonite shells. The pteropods evolved in the last 200k years, relatively quite recently. They’re more efficient at removing CO2 because they’re global rather than restricted to shallow near-continental shelf waters, and because the shells sink. They’re less efficient because they can’t make shells once the pH of the ocean reaches where it’s expected to be by 2100 — that’s chemistry, solubility, not climate change physics.

    You’d know this if you’d read any of the references.

    None of this matters on the human time scale; it’s on the human time scale we’re producing the huge spike in excess CO2, far more than biogeochemical cycling is equipped to handle at this rate of change.
    Hence the current excursion.

    Yes, nature is responding. But === read some of Margulis’s work, it’s an astonishingly complicated reassortment of living things to handle changes like this.

    From the same paper linked above:

    “How many secondary endosymbioses?
    With the realization that secondary-plastid-
    containing algae constitute a large proportion of the
    diversity of photosynthetic eukaryotes comes an
    important question: how often have these mergers
    happened? The integration of endosymbiont and host
    is an immensely complex series of events that has a
    formidable effect on both host and endosymbiont. It
    involves massive transfers of DNA between genomes,
    the development of a sophisticated protein-targeting
    machinery and a substantial reorganization of core
    and secondary metabolism. Untangling these events
    and understanding their effects on eukaryotic
    evolution requires fundamental knowledge of which
    algal lineages arose from the same endosymbiotic
    partnerships and which arose independently……”

    Yes, it’s happening now:

    http://links.jstor.org/sici?sici=0026-2803(2000)46%3C95%3ASFHOGC%3E2.0.CO%3B2-1
    Symbiont-Bearing Foraminifera: Harbingers of Global Change?
    P Hallock – Micropaleontology, 2000 – JSTOR

  206. hopp:

    volcanoes

    How much “new” CO2 did these eruptions release into the atmosphere?

    Tambora 1815
    Krakatau 1883
    Santa Maria 1902
    Mount Pelee 1902
    St. Helens 1980
    Nevado del Ruiz 1985
    Pinatubo 1991

    Somehow I don’t think it adds up only to 1% of man made CO2 emissions. I have read some scientists say that one such major eruption would release as much CO2 as ten years of human activity, but I don’t believe that either. What could be reliable estimations? And isn’t three major eruptions inside 11 years 1980,1985,1991 very rare in our age and doesn’t this correlate with the warming cycle?

    Then it’s said that there haven’t been this much CO2 in the atmosphere since 600,000 years ago. Well… 640,000 years ago the super Volcano of Yellowstone erupted with the power of 2,000 St. Helens, burying half of the North American continent in thick ash. How much CO2 was released? How did it affect the atmosphere, temperatures…?

    [Response:If volcanoes pumped out vast amounts of CO2, don’t you think we’d see spikes in the CO2 record? But we dont: e.g. here – William]

  207. tony:

    I am put in mind of Ptolmy who placed the earth at the centre of the universe,a view unchalleged for a millenia. In 1350 Giovanni de Dondi made a magnificent working model of Ptolmy’s universe, wheels within wheels made the planets turn back on themselves as they appeared to do when observed from earth.
    Brilliant, incredibly complex but wrong, in 1543 Copernicus put the sun at the centre of the solar system. The convolutions of the T/CO2 lag explantions rival Mr de Dondi’s clock, when just by saying the sun ‘s output varies, we explain the ice core record.

  208. Dave Rado:

    when just by saying the sun’s output varies, we explain the ice core record.

    Except that we don’t!

  209. tony:

    As the audience responds at an english pantomine – OH YES WE DO!!

  210. Dave Rado:

    But I didn’t find any answer in RC to a couple of important question raised – how many actual practising scientists are in the 2500 IPCC “consensus”? How many have resigned in the manner of the malaria expert, or asked to have their names removed as contributors?

    The answer to the second question is two, I believe – Reiter and Landsea. I don’t know the answer to the first, though I believe it is just over 2,000 – perhaps someone else can help with that.

  211. Dave Rado:

    Hi Tony – can you point to any peer reviewed evidence for your statement?

  212. tony:

    “There is no reason to believe that this 10,000-year-old cycle of solar-induced warming and cooling will change. Dr. Sallie Baliunas, an astrophysicist with the Harvard-Smithsonian Center for Astrophysics and one of the nation’s leading experts on global climate change, believes that we may be nearing the end of a solar warming cycle. Since the last minimum ended in 1715, Baliunas says there is a strong possibility that the Earth will start cooling off in the early part of the 21st Century.”

    I picked this at random from the internet, I have no idea who Dr. Baliunas is. My point is that his theory is more beleivable than yours.
    Until this documentary,I had never heard of the T/CO2 lag, and went along with the herd on the causes of global warming. IMHO your explanations of the lag do not stand up.

    [Response: He is a she. Just another reason to check your sources. -gavin]

  213. Mike Forster:

    Being relatively new to researching climate issues and accordingly having just read the above 200 or so blogs, I’m still in broad terms none the wiser having here found a collection of conflicting views, interpretations and opinions as opposed to any firm conclusions. Do we really have anything much more than a mere inkling as to what drives the climate through the ages?

    I personally found the Swindle programme entertaining in that it did, if little else, present a rather different view of things to that currently expounded by (what I suspect to be) grant-hungry scientists and tax-hungry band-wagon-vote-driven politicans (I’m in the UK BTW). (At the other end of the spectrum – and maybe in response to the Swindle program? – this last Sunday’s Sunday Times here in the UK carried a scare-mongering sensationalist article talking of the dire consequences of a 6C increase in global temp by 2100. The whole article was driven by the meanderings of a scientist called Lynas. How well is this chap regarded within the wider scientific community?)

    [Response: Mark Lynas is a journalist, not a scientist. – gavin]

    OK, so I’m no scientist myself – as will probably become apparent throughout the rest of this blog!. But I do have 3 degrees including a PhD, so I do not unreasonably consider myself able to appraise information in an ordered manner. That said, may I pose some (perhaps naive) questions.

    1. Has it been established beyond reasonable that CO2 has ranged between 180 and 280ppm during and between the last four Ice Ages?

    [Response: Yes. This comes from multiple ice cores. -gavin]

    2. What mechanisms have caused each of the last four Ice Ages to start against the backdrop of increasing global temperatures during the intervening Interglacial periods?

    [Response: Decreases in northern hemisphere summer solar radiation due to changes in the Earth’s orbit (Milankovitch forcing). -gavin]

    3. Now CO2 levels are at 380ppm. One has to assume that much if not all of this extra Co2 is down to us, no? If not what else could it be? In this regard, is there ANY credibility in the assertion as per the Swindle programme regarding the current elevated CO2 figure having rather more to do with the ‘delayed’ effect of the temperature rise in Medieval times rather than the burning of fossil fuels?? If so, is there any evidence that such temporary increases in CO2 have occurred before?

    [Response:All of the increase is anthropogenic. The last time CO2 was so high could have been 3 million years ago (the Pliocene), but possibly not for 25 million years. However, estimates that far back are much more uncertain. Certainly farther back than 800,000 years. Given our understanding of the carbon cycle, it is extremely unlikely that there have been any ‘peaks’ up to 380ppm over that time. – gavin]

    4. The question then is, what effect will this extra 100ppm (and that figure is almost certainly going to increase for a few more decades at least) of CO2 have upon our climate over the next century or two. I read somewhere above that each increase 0f 100ppm CO2 makes far less of a difference in increase of global temperature than did the previous increase of 100ppm oc CO2. If this is correct, then wouldn’t another increase in 100 ppm of CO2 from 380-480 only raise the global temp by a quarter of a degree or so?

    [Response: The impact is controlled by the climate sensitivity – generally given as the warming you expect from a doubling of CO2. This is around 3 deg C from multiple lines of evidence. From 280 to 380 ppm would be expected to give 1.2 deg C, from 380 to 480 around 0.9 deg C – both at equilibrium. You need to add in the other forcings (CH4, O3, CFCs, N2O, aerosols, solar) and take into account of the ocean lag to see where we should be now. However, stabilisation at 480 is an extremely challenging task. – gavin]

    Any and all input in response to the above would be appreciated. I know I’m no scientist so I don’t need reminding by flames! Try to remember that there are rather more people like me out there than people like you in here (-:

    Mike

  214. tony:

    I have just tried to post a random cutting from the internet supporting solar warming, my post was not allowed presuambly because the scientist named is on your list of dirty words.

  215. Dan:

    re: A “random cutting from the internet”? Goodness, that is not peer-reviewed scientific evidence. In fact, that is the ultimate example of using a non-scientific reference. Meanwhile, there are many scientific references right here on realclimate.org regarding the non-role of “solar warming”. Just do a simple search at the top of the page. Science is not a simple “random” personal opinion posted on the internet!

  216. hopp:

    few more points, before I shut up:

    It is estimated that during the Crecateous period the Earth temperature was 6-14 Celsius warmer than it is today. Atmospheric CO2 levels are estimated to have been 2-4 times (even 6x) higher than today. Unusually high volcanic activity is usually cited as the reason for the warmth. What is the relation to the high CO2 levels? And all in line with the CO2-GW theory… except that just before that period, during the large ice age of 150 million years ago, a time of glaciation and cold temperatures, atmospheric CO2 levels had been just as high. Dr. Giegengack of Penn. who has researched this, suggests that the fluctuations in the gas levels fall out of step with the planetâ��s hot and cold cycles, undermining the claimed supremacy of carbon dioxide, and adds: “People come to me and say, â��Stop talking like this, youâ��re hurting the cause’,

    Isn’t the argument about “spikes” rather speculative? Volcanoes set a convection pattern. CO2 (and other gases) go straight into upper atmosphere. This pattern brings fresh air from the surrounding area. Isn’t it then only logical, that the ground level CO2 stations will not record any spikes? Then the atmosphere has a mixing time of “how long?” and even larger eruptions get averaged, and will not be seen as spikes?

    During the Crecateous period the Earth bloomed with life. Continuous forests of gigantic trees, plants and animals covered all the land area. There was much more rain and there were no vast deserts.

    Is it necessarily the outcome of say 2-3C temperature increase that there will be vast and increased desertation in south? Isn’t it impossible to predict how the weather patterns would be affected? (We are still in the dark what really caused the droughts in 1980’s). Isn’t it also possible that rains will increase and things will turn better in say Africa?

    Things like desertation, hunger etc. are often quoted as the obvious outcome of any 2C+ AGW, but isn’t that also more about the pre-cautionary principle, than exact science to model such outcomes?

  217. tony:

    I am going to leave you Ptolmyean climatologists to it, hopefully there are enough Copernicans out there who can put up with the abuse and ridicule so that logic will prevail.

  218. Barton Paul Levenson:

    [[This is where GW falls apart for me, The process that starts the temperature rise is, as above, not understood. At best the C02 is a feedback, so what we are saying is: If we just add c02, without the event that starts the temperature rise, we will get global warming.]]

    That’s just basic radiation physics. Put more CO2 into the air and the ground will be warmer, all else held constant. That’s something we know from lab work dating to 1859.

  219. Barton Paul Levenson:

    [[Yes. But when the market is horrendously distorted by coercively-financed science, then what gets paid for is science that proves what those who want to coerce more money out of taxpayers want to have proved. If you prove that what is happening can only be solved by coercively destroying the free markets that have created the greatest improvements in the quality of human life, then you’re probably proposing a solution that can, at best, be called “evil.” ]]

    As far as I know, nobody is suggesting coercively destroying the free markets. Where did you get that idea?

  220. Geoff Wexler:

    BBC2 Newsnight 12th. March 2007
    They devoted a whole slot (perhaps 10 minutes) to the Channel 4 program as if it was a news item.

    It started with a sympathetic introduction by the presenter; there followed a replay of two extended sections from the Channel 4 programme about (a) the lags problem (showing Al Gore with the ice cores) and then (b) the two Danish graphs from Christensen and Lassen. This took up most of the program. They then introduced Paul Reiter on one side and Brian Hoskins from Reading (on the other) who were allowed a highly controlled debate. Hoskins just had time to talk about the lags and positive feedback but was cut short before trying to deal with the other issue of the solar correlations. This latter was most unsatisfactory. But I must admit that Hoskins was wasting time starting a sentence saying that evidence was very strong that “global warming was real”. It struck me that some genuine scientists are too busy to become experts in forensic matters ; why should they? I repeat that Al Gore’s film, good as it was, needs to have a second edition and or a successor by someone else, otherwise his opponents will succeed in confusing everyone. The BBC needs to be told about their propagation of two graphs one which has been cleaned up at the price of a discrepancy between sound and display and the other which has not been cleaned up and which (according to Damon and Laut) has a century long faked section. The correct graphs need to be televised.

  221. Barton Paul Levenson:

    [[If greenhouse gases trap heat from IR, do they also reflect some back? If this is so, is there not a balancing of the two i.e. as the greenhous gases increase the reflection of IR increases, therefore negating the heating effect of greehouse gases?]]

    No. At infrared wavelengths in Earth’s atmosphere, there is almost no reflection or scattering.

  222. Geoff Wexler:

    #183 and #189
    Bookeeping of radiation.
    Infra-red radiated from the ground is absorbed by greenhouse gases at higher altitudes where it is much colder. The same gases also radiate both back to the ground and upwards towards outer space where some of it eventually escapes. But radiation is lower at these cold temperatures (Stefan’s law) so the amount eventually lost to space is reduced compared to what it would have been without the greenhouse gases. Furthemore there is a balance between all these effects ; no need to fear that there has been a simple blunder in the bookeeping.

  223. Barton Paul Levenson:

    [[Dude… Think… CO2 can trap heat. It cannot reflect it out to space. It cannot funnel it through a wormhole to another region of space or even another universe. CO2 does not dissipate heat. What you are claiming is fanciful, to say the least. ]]

    CO2 doesn’t exactly “trap” heat. It absorbs infrared light, which heats the CO2 up. The warm CO2 radiates infrared light, some of which goes back to the ground and the rest of which goes to other layers of atmosphere or out to space. The heat isn’t permanently trapped anywhere.

  224. Barton Paul Levenson:

    [[“In order to reach 200 ppm, CO2 concentrations decrease. ”

    It doesn’t matter. At 200 ppm, CO2 traps enough heat to cause a rise in temperature. You said so yourself, on the way up. But somehow, you have convinced yourself that it expels heat when the temperature is decreasing. No. CO2 captures heat. It does not capture cold. It cannot work in the way you specify. CO2 will not reinforce a downward trend.]]

    He’s not talking about how CO2 works as a greenhouse gas. He’s talking about the amount of it in the atmosphere. What the CO2 concentration is does not depend, except perhaps very weakly, on CO2‘s greenhouse action. CO2 decreases in his scenario because the oceans absorb it.

  225. Barton Paul Levenson:

    [[The convolutions of the T/CO2 lag explantions rival Mr de Dondi’s clock, when just by saying the sun ‘s output varies, we explain the ice core record. ]]

    Do we? Cite a source, please, and explain the mechanism you’re talking about. Do you have a graph of Solar output versus temperature on the time scale of the ice cores?

  226. Andrew Dodds:

    Re: 216

    You are cartainly correct that there was plenty of life in the Cretaceous, and it was very much warmer. This appears to be a result of several things – higher GHG levels, no ice caps/ocean circulation to the poles, no large mountain areas comparable with Tibet, etc.

    Thing is, sea levels were of the order of 100 meters (300 feet) higher than today.

    It does not matter *what* the climate is – it is just that all of our human infrastructure is built around the current climate, and moving the climate makes a lot of that infrastructure obsolete. Think water, agriculture, house styles, etc..

  227. Ian Rae:

    Gavin, I would like to believe you, but some of your statements puzzle me. At one point you say “S+W’s study is incorrect, but even if we discuss that, you can always find another ‘confusing’ reference that we haven’t discussed. This is a real problem, and one where there is not an obvious answer.” You suggest that the “public shouldn’t listen to any one scientist (even me), but the assessments (IPCC, NAS etc.)”. The IPCC is a highly politicized body whose conclusions are signed off by governments, i.e. politicians. Given the whirlwind of AGW in the zeitgeist, one can hardly trust governments to be neutral on this topic.

    Later you respond to a simple question about T-CO2 lag with “The degree of that lag is actually quite uncertain and there is recent paper under review that suggests…” Given the huge amount of NAS & IPCC assessments, which you say people should trust more, why do you reach into a mirky bag of half-reviewed papers which “suggest” something? I may be completely wrong here, but it seems that rather than simply conceding “yes CO2 generally lags T” you resort to another confusing reference which happens to support your position. Surely this simple question about pre-20th century T/C02 lags can be answered better than that.

    I find it hard to believe that thousands of climate scientists are wrong, or caught up in some politicized delusion. If they say AGW is happening then I am prepared to accept that. But the tone used by some here about how “tired” they are of answering the same old questions is quite unhelpful. It’s understandable to be tired, but remember that you are calling for a fundamental change in our civilization that will cost trillions and take decades to accomplish. We need to check and check and check again.

    Anyway, thanks for this site; it’s one of the best on the web. It’s a good regular read.

    [Response: The IPCC is not politicized and the reports are not written by governments – though if it were, anything that got signed up to by countries as diverse as Saudi Arabia, the US and Albania must have something going for it! The reason why it’s on the shelf of every relevant scientist in the field is because it is a thorough and comprehensive assessment of the literature. Please read it – the TAR is online – and judge for yourself. On your second point, I gave you a straight answer. I simply pointed to current discussions that were relevant on which I don’t have an opinion (yet) (though if the lag disappears completely I’ll be quite surprised). It’s not ‘murky’ to acknowledge where the uncertainties and complexities are. -gavin]

  228. Reid:

    Thank you Marcus, James, David, Gavin, William, et al, for some very interesting discussions. I have learned a lot. Most prominently, I have learned that when climate scientists speak of “positive feedback”, they really don’t mean “positive feedback” in the sense, well, in the sense that it makes any sense. I came in here thinking that the proposal was that there were actually destabilizing feedbacks in the system and, this would indeed be a dire circumstance in my view. I was convinced that this could not be so because the instability would have already expressed itself in a dramatic and immediately observable way, as such things are wont to do.

    Now, I see that when you say “positive feedback”, you really almost always really mean “negative feedback”. Oddly enough, I simultaneously now find the AGW hypothesis more plausible but less worrisome. I really do believe you fellows need to revise your nomenclature. Feedbacks should be classified based on whether they are stabilizing or destabilizing. In systems described by differential equations, this dividing line occurs when the feedback has a negative or positive sign. Historically, these are the types of systems that were controlled by feedback and for which this nomenclature applied. When you are dealing in difference equations, stability is determined by the magnitude of the gain, rather than by its sign. Hence, speaking of positive or negative feedback gains in this context is misleading and really inappropriate.

    [Response: You appear to be on a different plane from everyone else here. Please read the refernce I gave you before. You are still very confused. -gavin]

  229. Liz Kalaugher:

    I’d be interested to find out more about the programme’s comments on malaria and global warming – it seemed to be saying that climate change will not affect the range of malaria-carrying mosquitoes. Is anybody able to say more about this?

    Incidentally, check out http://environmentalresearchweb.org/cws/article/research/27309
    for news of how 1987’s Montreal Protocol, designed to limit ozone-damaging chemicals, has also cut greenhouse gas emissions.

  230. Reid:

    #224 BPL – No. He was making the argument that CO2 was self reinforcing both when the temperature was going up and when it was going down. I was making the point that it cannot do both for the same system state. In fact, if Marcus’ little example can be thought of as representative, it is self reinforcing only on the way down because this is a stable system, what most people in stability circles would refer to as a “negative feedback” system.

  231. tamino:

    Re: #212 (tony)

    Dr. Sallie Baliunas, an astrophysicist with the Harvard-Smithsonian Center for Astrophysics and one of the nation’s leading experts on global climate change …

    I’m a mathematician, I worked for years doing time series analysis in astrophysics. I’m familiar with Dr. Baliunas, I’ve even referenced some of her work in my own publications.

    I sincerely want to know, where did hear that she is “one of the nation’s leading experts on global climate change”?

  232. Reid:

    Gavin – don’t blame me for your poor nomenclature. If you explained things to any controls engineer in the world the way you explained them to me, they would immediately make the same leaps as I did, i.e., “positive feedback? you must either have a runaway condition or a limit cycle.” The term “positive feedback” is a very loaded and alarming phrase in controls circles. When you call it this, and it turns out to, in fact, be a stabilzing feedback, you are apt to get gross misinterpretations when you present to a larger audience.

    What you need to get your mind around is what I have stated. Feedbacks need to be classified on the basis of whether they are stabilizing or destabilizing. When you take a set of difference equations and talk about feedbacks as either positive or negative, but this has no bearing on whether they are stabilizing or destabilizing, you might as well be calling them “charm” and “strange” feedbacks. Only worse, because the lack of information conveyed by the latter terms is better than the misinformation conveyed by the former.

    [Response: Misinterpretation are easily cured by reading the references. Try it. – gavin]

  233. Richard S Courtney:

    Dear All:

    I have scanned the above but not read it all. As one of those who is repeatedly (above) compared to a holocause denier I think you need to know that I very much enjoyed what I read: rarely have I laughed so much.

    Let us be clear. There is no evidence for man-made global warming; none, not any of any kind.

    The existence of global warming (GW) is not evidence of anthropogenic global warming (AGW) because warming of the Earth does not prove that human activity warmed it. At issue is whether human activity is or is not affecting the changes to the Earth’s temperature that have always happened naturally.

    Nothing is constant in nature: everything changes all the time. And the Earth must have warmed or cooled over the past 100 years if its temperature were not constant over the past 100 years.

    Two thousand years ago – in Roman times – the Earth was warmer than now. After that it was cooler than now throughout the Dark Ages. That cool period was followed by the so-called Medieval Warm Period when the Vikings farmed Greenland and an insect now constrained to the South of France inhabited York. Then the Earth cooled to the so-called Little Ice Age. The Earth has been warming out of the Little Ice Age for the 300 years since then. Around 1700, Londoners used to have “Ice Fairs” on the frozen Thames each year. The last Ice Fair was held in 1814, and the Thames has not frozen solid since.

    A claim that man-made global warming exists is merely an assertion: it is not evidence and it is not fact. And the assertion does not become evidence or fact by being voiced, written in words, or written in computer code. Furthermore, insults (e.g. comparison to holocaust deniers) directed at those who challenge the claim do not convert it into evidence either.

    The fact is that any warming that may have happened during the last 100 years is within natural climate variability that has occurred in the past. And that warming could be a completely natural recovery from the Little Ice Age that is similar to the recovery from the Dark Age cool period to the Medieval Warm Period.

    Furthermore, the history of the estimated warming of the Earth does not agree with an assertion that human emissions were responsible for the warming over the last 100 years. The estimates of the Earth’s average surface temperature (mean global temperature: MGT) all show warming from before 1900 to 1940, then cooling from 1940 to 1970 with a further period of warming after 1970.

    The estimates show that most of the warming occurred before 1940 but 80% of the emissions were after that. Indeed, the start of the cooling period coincided with the start of the major emissions. Advocates of man-made global warming excuse this problem by attributing
    (a) almost all the rise before 1940 to be an effect of the Sun,
    (b) the cooling from 1940 to 1970 to be an effect of human emissions of aerosols, and
    (c) the warming after 1970 to be mostly an effect of human emissions of greenhouse gases.
    Evidence is lacking for this convoluted story to excuse the disagreement of the emissions with the temperature history.

    And there are several good explanations for the variations in global temperature over time. For example, clouds reflect solar heat and a mere 2% increase to cloud cover would more than compensate for the maximum possible predicted warming due to a doubling of carbon dioxide in the air. Good records of cloud cover are very short because cloud cover is measured by satellites that were not launched until the mid 1980s. But it appears that cloudiness decreased markedly between the mid 1980s and late 1990s. Over that 15-year period, the Earth’s reflectivity decreased to the extent that if there were a constant solar irradiance then the reduced cloudiness provided an extra surface warming of 5 to 10 Watts/sq metre. This is a lot of warming. It is between two and four times the entire warming estimated to have been caused by the build-up of human-caused greenhouse gases in the atmosphere since the industrial revolution. (The UN’s Intergovernmental Panel on Climate Change says that since the industrial revolution, the build-up of human-caused greenhouse gases in the atmosphere has had a warming effect of only 2.4 W/sq metre). Why should cloud cover vary? Well, the Sun’s activity varies and this alters the flow into the air of cosmic particles that initiate cloud formation.

    But the fact that there is no evidence for AGW is not evidence that AGW is not happening. Simply, there is no evidence that AGW is happening, and there is no evidence that AGW is not happening, either.

    Do not forget that global temperature has not again reached the high that it did in the El Nino year of 1998. And please beware assertions from people (such as the hosts of this blog) who are making a good living from the global warming scare.

    All the best

    Richard

  234. Hank Roberts:

    She’s described that way at denial and Western Fuels PR sites — OISM, junkscience, GreeningEarth; Google will get you the list.

    She’s got quite a record for being wrong; one of the great papers in that regard:
    http://johnquiggin.com/wp-content/uploads/2006/01/baliunas_report.pdf
    (link found here)
    http://johnquiggin.com/index.php/archives/2003/09/14/junk-science-on-ozone/
    is awfully hard to find, none of the denial sites feature it any longer. Guess why?

    http://www.sciencedaily.com/images/2006/10/061019162053.jpg

  235. Hank Roberts:

    Reid, you’re confusing physics with biology.

    Do you have a lawn? Do you understand the effects of nitrogen fertilizer on the color of the grass?

    Try an experiment: Make a checkerboard of meter squares with string and pegs, say 6×6 if it’s that big, or something proportional.

    Get some 1:0:0 (all nitrogen, no phosphorous or potassium) lawn fertilizer./
    Mix it in water at 0.1x recommended, 1x recommended, and 10x recommended amount of nitrogen.

    Randomize application to a third of the squares with each amount.

    Result will be illustrative of how biological systems respond. 0.1x, not much change; 1x, much greener; 10x, yellow and/or dead.

    Oh, this may be better done as a gedankenexperimenet, if you value the place you live.

  236. Dan:

    re: 232. Your apparent failure to understand the basic science involved is only matched by the gross disinformation you are spreading. The science behind global warming is unequivocable. The research is strong and published in peer-reviewed journals. To think anything less is disingenuous to say the least.

  237. tamino:

    Re: #232 (Richard Courtney)

    All your mistakes and mischaracterizations are not evidence, and they do not become so by virtue of your posting them on a blog comment.

    Go to the Goddard Institute for Space Studies or Hadley Centre for Climate Change and look at the real data — not the lies you’ve been told by denialists.

    As for your very snide comment to “please beware assertions from people (such as the hosts of this blog) who are making a good living from the global warming scare,” you remind me of the episode of The Simpsons in which they visit a chimp researcher in Africa — loosely based on Jane Goodall — who is secretly forcing the chimps to work in a diamond mine. At one point Homer lies on the bed throwing diamonds over himself, saying “Woo-hoo! Look at me! I’m a scientist!”

  238. Ike Solem:

    Dear Richard S Courtney,

    I think most climate scientists would be happy to see evidence that fossil-fueled global warming effects will be minimal, but all the evidence points in the other direction.

    The evidence is fairly clear, particularly in the polar regions (thinning sea ice, rising ocean temperatures) and at higher elevations, as climate models predicted. The changes in the hydrologic cycle as a result of the greenhouse gas induced-warming (i.e. the positive water vapor feedback effect) is also progressing as predicted.

    Generally speaking, if you make a theoretical prediction that is borne out by experimental or observational evidence, that means that the science behind the prediction is robust. Thus, thanks to climate modelers and satellite and ground observations, we can see that the climate is changing, and the explanation that fossil fuel CO2 is the cause is indeed well supported.

    We are also seeing the continuing slow rise of sea level, which may accelerate in the future due to the dynamic behavior of ice sheets, which don’t behave like static ice cubes, but rather which can flow at different speeds. We are also seeing some changes in ocean circulation. Thus, the conclusion is clear – the planet is warming, the climatic patterns are changing, and this is not a natural fluctuation, but rather the effect of burning large amounts of fossil fuels, particulary coal.

    You also say, “And please beware assertions from people (such as the hosts of this blog) who are making a good living from the global warming scare.” However, a quick check reveals that you yourself are a “Technical Editor for CoalTrans International (journal of the international coal trading industry)…. In the early 1990s Courtney was a Senior Material Scientist of the National Coal Board (also known as British Coal) and a Science and Technology spokesman of the British Association of Colliery Management.” From Sourcewatch

    Given that the single most important step in slowing global warming is ending the use of coal for energy on a global basis, shouldn’t readers be concerned that your position is not exactly that of the disinterested observer? On the other hand, you deserve commendation for using your real name, unlike others who post similar comments at RC.

  239. Mike Forster:

    Many thanks to Gavin for the clarification.

    Gavin states:

    “All of the increase is anthropogenic. The last time CO2 was so high (i.e. 380ppm) could have been 3 million years ago (the Pliocene), but possibly not for 25 million years. However, estimates that far back are much more uncertain. Certainly farther back than 800,000 years. Given our understanding of the carbon cycle, it is extremely unlikely that there have been any ‘peaks’ up to 380ppm over that time”

    That said, is there ANY chance that at least some of the CO2 increase (i.e. from 280 – 380ppm over the last 150 years) is the result of the CO2 ‘lagging’ behind the Medieval warm period?? Based upon your surmisal above, there is either no correlation between warm periods and several-hundred-year-later-CO2 spikes OR there have been no other such warm periods during the last 800,000 years (at least if the ice core records are reliable). I find the latter very hard to believe…. so is the T/CO2 time lag thing all a load of bunkum??

    Gavin also states:

    “The impact is controlled by the climate sensitivity – generally given as the warming you expect from a doubling of CO2. This is around 3C from multiple lines of evidence. From 280 to 380 ppm would be expected to give 1.2 deg C, from 380 to 480 around 0.9 deg C – both at equilibrium. You need to add in the other forcings (CH4, O3, CFCs, N2O, aerosols, solar) and take into account of the ocean lag to see where we should be now. However, stabilisation at 480 is an extremely challenging task.”

    Are there currently anything like reliable models for the other forcings you refer to? There are an awful lot of variables there. As well as ‘positive’ (bad news) feedbacks, aren’t there conversely any ‘negative’ (good news) feedbacks which could factor in? I only ever see ‘positive’ feedback mentioned.

    Some other questions if I may:
    1. Could we drop the average global temperature by 1C if we painted ALL roofs white, or are such assertions in some of the popular media rubbish?!
    2. Has anyone given any thought to ameliorationg the effcts of AGW (if it is indeed happening) by deliberately and systematically putting tiny reflective (‘global dimming’) particles up into the atmosphere? Say with an engineered (degradable) lifetime? (i.e. particles working much like the aerosol-driven cooling of recent decades.)
    3. Is there much truth in the fact that the planet’s 1.5bn cattle put out way more greenhouse gases (CO4) than all forms of human transport (CO2) put together? Anyone have any hard data in this regard? If so, could we all do far more good by becoming vegetarian than abandoning driving and flying?
    4. The Swindle programme also referred to anthropogenic CO2 output as being insignificant when compared to decaying vegetation (16x more than human CO2 outsput) and even more insignificant compared to CO2 output from the sea. Any one have any data one way or the other? Did the programme simply ignore the recyclability (intrinsic balance between photosynthesis and respiration) of the former and the significant centuries lag associated with the latter? That said, I suppose if any of the aformentioned assertions as per the Swindle programme have any merit, then one still has to then ask why CO2 has gone up 36% this last 150 yrs!
    5. If the vast scale of the Earth’s regulatory systems make them commensurately slow (centuries/millenia) to react to ‘prodding’ (here anthropomorphic CO2 output), then why do some scientists postulate such doomsday scenarios in as little as 50-100 years (eg the Sunday Times mag article of 11th March by the journalist Mark Lynas)?? From Wikipedia: ‘If all glaciers and ice caps melt, the projected rise in sea level will be around 0.5 m. Melting of the Greenland ice sheet would produce 7.2 m of sea level rise, and melting of the Antarctic ice sheet would produce 61.1 m of sea level rise.’ To a layman like myself, its hard to envisage the melting of either the Greenland or Antarctic ice sheets taking anything other than hundreds if not a few thousand years to melt even with a 6C temperature rise. As such – and to me at least – the IPCC estimates of sea level rises of between 180 – 590mm seem to be ‘on the money’ as it were. Do other bloggers accord?
    6. Lastly; is there any hard evidence that recent warming is a) entirely or even largely due to observed rises in CO2 levels and is NOT at least partly due to other non-anthropogenic factors? Surely the Earth’s dynamic climate is massively intricate and liable to vary over decades, centuries and millenia REGARDLESS of anthropogenic factors: couldn’t much or even most of the observed warming have happened even if post-Industrial Revolution man hadn’t been around the last 150 years??

    Thanks again for the great site.

    Mike

  240. Flightless Bird:

    I have been posting on a general message board (hence the silly name here) and trying to explain what climatologists think and why, and why the program was misleading. One question that I’ve been asked, to which I can’t find an answer by googling, is how much CO2 is being produced by other means than volcanoes (3% or whatever) and anthropogenic sources (97%). Relatively how much CO2 is produced through respiration by all the living organisms? All I can find is the net carbon fluxes for the ocean and land. Thanks.

  241. David B. Benson:

    Re #200: Reid — Yes, it is believed that the pulse of carbon dioxide being introduced into the climate system will eventually go away. The paper

    David Archer & Andrey Ganopolski
    A movable trigger: Fossil CO_2 and the onset of the next glaciation
    Geochemistry/Geophysics/Geosystems: AN ELECTRONIC JOURNAL OF THE EARTH SCIENCES

    considers the matter. Assuming antropogenic carbon can be limited to 1000 Gt (currently 300 Gt) then the climate system returns to normal in about 150,000 years.

    Regarding the role of carbon dioxide in the climate of the past, the so-called greenhouse gases are only one component of a system with many known (and probably some still unknown) interactions. For example, the greenhouse gas concentration changes only explain about half of the observed temperature change from LGM to the Holocene Thermal Optimum, about 6 K.

  242. Reid:

    Hank – I’m not confusing anything. The response is nonlinear. I got that just fine. I deal with grossly nonlinear systems all the time.

    The system Marcus provided was very helpful. But, this is not a positive feedback system in the usual and logical sense of the phrase. It is stable to the equilibrium point. It does not help you raise the temperature, though the temperature can rise on its own for a finite interval, what we call a transient. However, the appropriate norm of the entire state always decreases in the absence of forcing. Once you take the forcing away, it immediately starts heading back to the equilibrium.

    That’s a good thing. If this little system is representative, it means the climate is not self-reinforcing and that perturbations in the form of exogenous inputs will be degained by the feedback loop. This does not mean that exogenous inputs cannot force a new and hotter equilibrium point to be established. It just means that, once these forcings are taken away, it will not keep on driving itself upwards. That was my concern. That was my source of doubt, as such a runaway or limit cycle should have occurred in the past and the lack of such an evident instability in the climate record would appear to contradict the thesis. Let me be clear: the AGW hypothesis remains viable, just not in this more virulent form based on the preceding assumptions. And, for me, that is a source of some comfort.

  243. John Pepper:

    I would just like to put on record that from a layperson I think this site is an excellent resource and of great value. Like one of the contributers above I didn’t watch the programme because I thought I would just get far too annoyed (and not be able to argue back). Its great to be able to come on here and read the background to the science. On the back of this site I have complained to Channel 4 and also to Dominic Lawson in the UK paper the “Independent” who made some supportive comments both before and after the programme.

    As a scientist who graduated 20 years ago, I think the level of this site is just about right and I feel I can always find a link to a helpful article which can explain things too me.

    Keep up the good work!
    John

  244. tamino:

    1. Could we drop the average global temperature by 1C if we painted ALL roofs white, or are such assertions in some of the popular media rubbish?!

    I don’t know. But here’s a back-of-the-envelope calculation.

    Guess: 500,000,000 rooftops.
    Guess: average rooftop area 400 m^2. That’s 0.04% of the earth’s surface.
    Guess: painting it white would increase its albedo by 0.5
    Therefore painting them all white would increase planetary albedo by 0.0004 (actually a bit more, because they’re mostly in lower latitudes, but this is just back-of-the-envelope)
    Climate forcing due to increase of albedo by 0.0004: 0.14 watts per square meter (W/m^2)
    Temperature change (using sensitivity of 0.8 deg.C per W/m^2): around 0.1 deg.C

  245. tamino:

    Re: #244

    Correction to the back-of-the-envelope calculation.

    Increasing the albedo of 0.04% of earth’s surface by 0.5 leads to net albedo increase of only 0.0002. So the temperature change would actually be closer to 0.05 deg.C

  246. Hank Roberts:

    Reid — type “Venus” into the search box at the top of the page; I guess that’s what you were afraid was predicted. Not so.

    Meanwhile, I see something interesting happening in the WSJ’s business section:

    Treasury’s Paulson Suggests
    ‘Principles-Based’ Regulation
    By BENTON IVES-HALPERIN
    March 13, 2007 1:01 p.m.

    “Treasury Secretary Henry Paulson said Tuesday that U.S. policy makers should consider adopting “principles-based” regulations and accounting standards, in part to keep pace with increasingly competitive global capital markets.
    (Read the text of the speech.)

    http://www.treas.gov/press/releases/hp306.htm
    —- quote —-
    “We should assess how the current system works and where it can be improved…. And we should also consider whether it would be practically possible and beneficial to move toward a more principles-based regulatory system, as we see working in other parts of the world.

    “Our goal should be better managed, more competitive corporations that earn investor confidence through sound leadership, thoughtful governance, and outstanding performance. In my judgment, we must rise above a rules-based mindset that asks, “Is this legal?” and adopt a more principles-based approach that asks, “Is this right?”
    —– end quote——
    That should be reassuring to the coal companies, who, presumably also want to do what’s right — but right now fear they will be sued if they do anything reducing shareholder short term profit by admitting that changing the climate is an externalized cost of burning fossil fuel.

    Good news, for a change, eh?

    He also says, just after the above:

    “And we should consider whether our legal system appropriately protects investors or gives too much latitude to unscrupulous lawyers.”

  247. Barton Paul Levenson:

    [[Let us be clear. There is no evidence for man-made global warming; none, not any of any kind. ]]

    99% of climatologists seem to disagree with you.

  248. Richard S Courtney:

    Dear All:

    re postings 236, 237 and 238. I correctly and accurately said there is no evidence for man-made global warming; none, not any of any kind. The responses say there is some such evidence but cite no such evidence (which is not surprising because there is none). However, the responses do provide insults (as is usual from global warming fanatics).

    Nasty, nasty, nasty.

    Me, I prefer science not this anthropogenic global warming superstition.

    Now, would anybody like to comment on the facts that I cited pertaining to cloud cover? Oh, sorry, that was science so perhaps I raised it in the wrong place.

    Richard

  249. Arne Melsom:

    Living in Norway, I’ve taken the opportunity to look at the documentary on http://video.google.com, I searched for “BBC Documentary The Great Global Warming Swindle” (I thought this wasn’t a BBC documentary -but it must be the right program).

    I discovered something interesting. At approximately 29:00 there is a curve that shows the solar activity vs. global temperature. And at about 33:25, there it is again, but now with global temperatures replaced by those in the Arctic. But wait! The latter shows the development until the end of the last century, while the former global time series ends at about 1980. I guess global temperatures are not yet available for the last 20 years… Surely, the viewers haven’t been swindled!?

    I haven’t read thru all the 200+ postings, so I realize that I may not be the first one to notice this.

  250. Dan:

    re: 248. No, you do not understand the basics of the scientific process/method. You have preconceived ideas with no interest whatsoever in learning about the science. Until you do, your thoughts have no merit. When you can cite peer-reviewed articles to substaniate your views, people may take you seriously. Insulting people (“rarely have I laughed so much”) is the internet cry of the desparate and cornered. And insulting science and scientists when you do not understand it from the start will get you nowhere. Worse yet is pretending that you know the science. That is simply a sorry reflection on the state of science education.

    You can easily do a search on “cloud cover” and learn something right here on this site but you apparently, lazily choose not to. In other words, you are a drive-by poster, with no interest in learning about the unequivocable science (it is basic physics), what a consensus means, what peer-review is for, or the fact that virtually every major scientific organization across the world concerned with climate research agrees regarding the man-made influence of CO2 on global warming since about 1970.

    Your choosing 1998 as a “peak” year is simply disingenous since someone who understands science and climate would know that was an extreme El Nino year that simply added to the global warmth that year. If you knew basic statistics you would also know that one year does not make a trend.

    Insults to science and scientists as a whole such as “nasty, nasty, nasty” does nothing to support your position such as it is and simply sounds shrill. Not understanding and throwing out insults is nothing but desparate arrogance. Being accountable and being able to admit you are in error or wrong is a start in the right direction. The science simply does not support your opinions.

    Look at the data. Read the science. Learn from it. There is no excuse if the data and science do not agree with with you want it to say. And simply repeating something you think over and over with no science to support it does not make it any more accurate or truthful.

  251. Hank Roberts:

    > Richard S. Courtney

    Several show up; would you be this gentleman?
    “Dr. Richard S. Courtney, climate and atmospheric science consultant”
    http://www.canada.com/nationalpost/financialpost/story.html?id=3711460e-bd5a-475d-a6be-4db87559d605

    Or this gentleman?
    “Richard S. Courtney, Ph.D., ESEF – European Science and Environment Forum, UK, EU.”
    personal.inet.fi/koti/hameranta/appendix.htm

    Or one of those at a US academic address? Hard to be sure who we’re hearing from here, with so many people of the same name.

  252. tamino:

    Re: #248

    Dear All except Richard,

    Richard’s characterization of the history of earth’s temperature still isn’t right, and his assertion without evidence still doesn’t hold water. I pointed him to GISS and HadCRU, but he protests that we haven’t provided any evidence. He probably hasn’t been there or he’d be admitting at least some of his misstatements.

    Instead he has the gall to accuse us of insulting him, when one of my original objections was his having insulted the moderators of the blog, in most smug and snarky fashion. And he has been exposed as a shill for the coal industry.

    This is clearly an attempt to provoke us. It can’t be taken seriously as an attempt to deny global warming; his post is far too amateurish to be any good at that. So my advice to all the regulars is: do not feed the troll. Let him have the last word if he wants it, but give him all the response he deserves: none.

  253. David B. Benson:

    Re #248: Richard S. Courtney — I encourage you to read

    W.F. Ruddiman
    Earth’s Climate: Past and Future

    to aid in correcting your misinformed condition.

  254. Patrick Hadley:

    Can anyone give answers to someone puzzled by the Channel 4 programme. No doubt these questions are fully answered on other parts of the site, but there are probably plenty of people who are visiting the site for the first time – seeking more understanding after seeing the Channel 4 programme. Please indulge my ignorance – I suspect that I am not going to be the only visitor to this site in that condition.

    What percentage of CO2 emissions into the atmosphere are anthropogenic? The programme said it was quite a small proportion compared to the total emitted in other ways? Is that true? I have noticed the volcano effect being discounted but what about the rest?

    The programme said that CO2 was only a small part of the greenhouse gases and that water vapour was much more important. Is this true and if so is it relevant?

    I have read some of the links about the “800 year lag” and find the responses unconvincing. Am I right in saying that over 420,000 years in every warming/cooling cycle CO2 has always followed the pattern set by temperature. Imagine a cycle that lasts 10,000 years. For 800 years (plus or minus 200 years)after the temperature has started rising the CO2 in the atmosphere is actually falling. For 4,200 years they both rise; then for 800 years temperature is falling while CO2 levels continue to rise. There then follows another 4,200 years while both temperature and CO2 fall before the cycle starts again.

    Now obviously something has caused the temperature variation to start in a particular direction – and it cannot have been CO2. It appears that in the past global warming always began when CO2 was at a relatively low level and dropping for 800 years, and that global cooling started when CO2 was always at a relatively high level and rising for another 800 years.

    I am a simple mathematician who never thought of himself as a sceptic, still less a denialist. Can those who know far than I do about this subject explain these difficulties?

  255. Dave Rado:

    Relatively how much CO2 is produced through respiration by all the living organisms? All I can find is the net carbon fluxes for the ocean and land. Thanks.

    In terms of net contribution, zero, because that forms part of the carbon cycle – http://www.grida.no/climate/vital/13.htm .

    In the natural process, for roughly the last 10K years until the industrial revolution, every giga tonne of carbon going into the atmosphere was balanced by one coming out. Since we began burning fossil fuels in ernest over 150 years ago, the atmospheric concentration that was relatively stable for the previous several thousand years (http://www.brighton73.freeserve.co.uk/gw/paleo/20000yrfig.htm ) has now risen by over 35% (http://en.wikipedia.org/wiki/Image:Carbon_History_and_Flux-2.png ).

    A good place to go for information like this is http://gristmill.grist.org/skeptics.

  256. David B. Benson:

    Re #254: Dave Rado — Both of your links appear to be broken.

  257. Dave Rado:

    There were more than two links in my last message, but the others didn’t display as links because I had put brackets round them.

    The gristmill site appears to be down temporarily but the following article answers your question and the links from it do all work:
    http://illconsidered.blogspot.com/2006/03/natural-emissions-dwarf-humans.html

  258. Hank Roberts:

    Dave R., your links accidentally include the periods following them, that’s the problem — David B, just copy all but the dot at the end and paste that into your browser, to follow the links.
    http://www.grida.no/climate/vital/13.htm
    http://gristmill.grist.org/skeptics

    See also the last several threads here on what’s known about T/CO2: http://www.scienceblogs.com/stoat/

  259. tamino:

    Re: #254 (Patrick Hadley)

    What percentage of CO2 emissions into the atmosphere are anthropogenic? The programme said it was quite a small proportion compared to the total emitted in other ways? Is that true? I have noticed the volcano effect being discounted but what about the rest?

    I don’t know the numbers, but I do know that the anthropogenic emissions of CO2 are far smaller than those from other sources (except volcanos, which are tiny by comparison). For example, emissions from the oceans each year are about 90 GT.

    But all the other sources absorb as much as they emit; they’re in equilibrium. Of course the “documentary” failed to mention this. The net contribution from those other sources is zero.

    And in fact, even that is not quite true. Lately, the ocean is taking more than it gives; the oceans are absorbing about half the CO2 emitted by humans, and are acidifying as a consequence. Many consider this a great threat to marine ecosystems.

    We know for certain that the rise in CO2 is due to the burning of fossil fuels. Fossil-fuel carbon has a different isotopic composition than other sources; it’s depleted in C-13 (because its origin is organic plant matter) and depleted in C-14 (because it’s been buried underground for millions of years). The isotopic composition of carbon in atmospheric CO2 is changing in exactly the way we’d expect if — and only if — the source is the burning of fossil fuels.

    The programme said that CO2 was only a small part of the greenhouse gases and that water vapour was much more important. Is this true and if so is it relevant?

    This is another example of the disingenuous nature of the “documentary.” It’s true that H2O is the dominant greenhouse gas in the atmosphere. But that doesn’t mean that the effect of CO2 (and CH4, N2O, etc.) is negligible. The most disingenuous part is that many of the participants know this.

    I have read some of the links about the “800 year lag” and find the responses unconvincing. Am I right in saying that over 420,000 years in every warming/cooling cycle CO2 has always followed the pattern set by temperature. Imagine a cycle that lasts 10,000 years. For 800 years (plus or minus 200 years)after the temperature has started rising the CO2 in the atmosphere is actually falling. For 4,200 years they both rise; then for 800 years temperature is falling while CO2 levels continue to rise. There then follows another 4,200 years while both temperature and CO2 fall before the cycle starts again.

    It’s hard to say about every cycle, because the timing is hard to pin down with sufficient precision. From what I’ve seen, in some cycles, CO2 appears to be stable (not declining) during the approx. 800yr lag, in some cycles it appears to decline.

    As to why CO2 doesn’t rise until after temperature begins to rise, consider that it has to! CO2 doesn’t increase for no reason. One of the things that can make it rise is warming of the oceans (which reduces the solubility of CO2). There is also indication that the melting of ice sheets can release CO2 trapped in the ice.

    None of which alters the fact that CO2 is a greenhouse gas and contributes to the net warming. I’ve seen estimates that greenhouse gases are responsible for about half the net warming during a deglaciation.

    Now obviously something has caused the temperature variation to start in a particular direction – and it cannot have been CO2. It appears that in the past global warming always began when CO2 was at a relatively low level and dropping for 800 years, and that global cooling started when CO2 was always at a relatively high level and rising for another 800 years.

    What starts the warming is probably (correct me if I’m wrong, guys) the melting of ice sheets. Ice is highly reflective, so reducing ice coverage reduces the albedo (reflectivity) of the earth, allowing more of the incoming solar energy to be absorbed, and therefore available to the climate system.

    What starts the melting is changes in the orbit and tilt of earth. This redistributes incoming solar energy so that more of it strikes high latitudes, which causes melting of high-latitude ice.

    And again, the 800yr lag is probable but highly uncertain. I’m not sure that all warmings are accompanied by 800yr of CO2 falling (I think some of them have CO2 stable), or that all coolings are accompanied by CO2 rising. Anybody know the details?

    I am a simple mathematician who never thought of himself as a sceptic, still less a denialist. Can those who know far than I do about this subject explain these difficulties?

    I too am just a simple (but not always modest) mathematician.

  260. Sudha Shenoy:

    1. So Richard Courtney is ‘a shill for the coal industry’. Fine. This means his papers need not be examined for their science? It is automatically wrong?

    2. Thousands of scientists now make a living from the billions of dollars available to study global warming. There is no money available from govt for the opposite. Suppose the situation were reversed? What then?

  261. george-t:

    Was Richard Lindzen swindled by the producers of the appropriately named documentary or did he voluntarily mislead the viewers? In the middle of a section about changes in tropical storms with global warming he was shown commenting that global warming theory predicts a decrease in equator-to-pole temperature difference which implies a decrease in storm strength and frequency. A true statement but one that, as he certainly knows, applies to midlatitude storms and has no direct relevance to tropical storm activity. I would like to think that the comments were inappropriately positioned by the documentary producers who seem to specialize in the particular activity. It would be sad for our field if they were knowingly made in that context.

  262. James:

    Re #254: I think this question needs further comment:

    [The programme said that CO2 was only a small part of the greenhouse gases and that water vapour was much more important. Is this true and if so is it relevant?]

    This illustrates one of Heinlein’s classic ways to lie: tell the truth, just not all of it :-) What they don’t tell you is that 3/4 of the Earth’s surface is covered with water. Water goes quickly between vapor & liquid/solid, so that the atmosphere is always going to have as much as local conditions permit. It’s mainly that existing water vapor that keeps the Earth at its fairly comfortable temperature, instead of somewhere below freezing. (You can find more accurate numbers if you look around this site.)

    Unlike water vapor, CO2 sticks around for a long time, centuries or more, so the amounts humans add keep accumulating over the years. And here’s the real kicker: if increased CO2 warms the planet a little bit, that causes more water to evaporate from the oceans. Since water vapor is a greenhouse gas, the reality is that it acts to amplify any temperature increase caused by CO2, just the opposite of what the program would have you believe.

  263. James:

    Re #216, 226: [You are cartainly correct that there was plenty of life in the Cretaceous, and it was very much warmer…]

    Many other things were different then: the composition of the atmosphere was different, there’s evidence for higher atmospheric pressures, the continents were arranged differently, etc. One thing to remember, though, is that whatever conditions prevailed during the Cretaceous (or most other periods) took millions of years to develop. The plants and animals had time enough to evolve to suit the conditions.

    You also might reflect on the fact that an awful lot of the species that were living happily in Cretaceous conditions are now extinct.

  264. Gavin McP:

    The UK Independent newspaper has discovered where that temperature graph came from. In summary: they used out-of-date data and got the scale on the bottom of the graph completely wrong – the temperature series actually ended “in the early 1980s”.

    “The original Nasa data was very wiggly-lined and we wanted the simplest line we could find,” Mr Durkin said.

    Oh, dear. There are further revelations in the article .

  265. AdrianJC:

    BBC Radio4’s Today programme just had a climate scientist (not sure who) on phone interview to challenge a Channel 4 representative. The C4 guy defended the whole programme and said he didn’t see how Carl Wunsch was misrepresented at all. When the scientist challenged him on specific points, he refused to address them and started talking about the sun and that minority opinions need to be represented. The climate scientist didn’t come across too well on the radio interview though, perhaps because he wanted to cover too much ground in so little time. The scientific jargon and reiterating the ICPP conclusion quickly loses the listener such that at the end of the ten minute piece they think there is still a debate, and that the C4 programme has some scientific merit.

    What real climate scientists need to highlight are the omissions and distortions that demonstrate beyond reasonable doubt that the intent was to mislead, and not to present alternative scientific explanations. Failing to mention sulphate aerosols had a big part to play in 1940-1970, distorting the graphs, outright lies like the ice cores being the only evidence of a link between CO2 and T, using scientists quotes out of context, using out of date data (satellites and radiosondes) when the recent datasets don’t support the controversy, accusing modellers of using exagerated CO2 increases, limiting icecap footage to the 1990s and not 2000s when the north pole turned liquid, to name but a few.

  266. John Pepper:

    Dear All

    You will be pleased to learn that the UK paper The Independent has today published a full one page article taking some of the points raised here and highlighting the inaccuracies in the programme. Its nice to get some coverage like this in the media as it is a rare event to publish corrections. You can read the article here: http://news.independent.co.uk/environment/climate_change/article2355956.ece In the newspaper they publish 3 graphs from the programme, alongside the corrected versions.

    And I just LOVE these comments from the producer:

    Mr Durkin admitted that his graphics team had extended the time axis along the bottom of the graph to the year 2000. “There was a fluff there,” he said.

    The original Nasa data was very wiggly-lined and we wanted the simplest line we could find,” Mr Durkin said.

    Enough said!

  267. Jakob:

    The Channel 4 documentary was brilliant at pointing out how the alarmism has become an industry. It could have looked further into how damaging following this political agenda of anti-development will be and how much less developed and well off we would be without following the climate-hysteria political agenda.

    J, Denmark

  268. Mike Forster:

    Re#259 Tamino states:

    “I don’t know the numbers, but I do know that the anthropogenic emissions of CO2 are far smaller than those from other sources (except volcanos, which are tiny by comparison). For example, emissions from the oceans each year are about 90 GT.

    But all the other sources absorb as much as they emit; they’re in equilibrium. Of course the “documentary” failed to mention this. The net contribution from those other sources is zero.

    And in fact, even that is not quite true. Lately, the ocean is taking more than it gives; the oceans are absorbing about half the CO2 emitted by humans, and are acidifying as a consequence. Many consider this a great threat to marine ecosystems.”

    Maybe I’m missing something here. So the oceans emit 90 GT CO2 per year. Anthropenic emissions of CO2 are 6.5 GT per year. So just how can it be that ‘the ocean is taking more than it gives’?? Or do you mean that the oceans emit AND THEN RE-ABSORB 90 GT per year PLUS THEN they have to absorb half of the anthropogenic output ON TOP??

    I’m assuming you guys have seen/heard of this 2002 paper (its the first thing I found when looking for a current annual figure for anthropogenic CO2 output).

    http://www.climatechangeissues.com/files/s…e/defreitas.pdf

    Interestingly, it makes – amongst others – the following points:

    *Anthropogenic (human) CO2 contributes 6.5 Gt to the atmosphere per year.
    *Biomass absorbs 10 Gt per year, which is three times the net increase from fossil fuels.
    *CO2 increase is levelling off due to increased plant growth absorbing CO2.
    *CO2 increase is variable and in 1992 was zero.
    *Anthropogenic CO2 contributes 3% of the natural Carbon Cycle.
    This is less than 1% of the atmospheric reservoir of 750 Gt CO2.
    *The CO2 increase is following a 300 year global warming trend.
    *The well known Vostok Ice Core data shows that CO2 increases lag 600 years behind temperature increases.

    I know and appreciate that the above paper is from a petroleum geology journal, but it looks to me (as a non-scientific though nonetheless PhD-educated individual) to be well written and referenced. Just how many of the extracted statements above are actually incorrect and/or irrelevant?

    OK, so petroleum companies are obviously dollar-driven, but I don’t think there’s any hiding from the fact that the current green shift in politics is to no small extent driven by politicians’ egos/political ‘band-wagoning’ and, way more importantly, the need to raise ‘green’ taxes to address some horrendous governmental financial defecits in Western economies. There is similarly little doubt that AGW scientists also require funding dollars and public recognition/kudos! So given the obvious and inescapable dichotomy between the oil-driven powers-that-be and green-tax-dollar and ego-driven politicians (both of who can easliy manipulate and distort the findings [e.g. the IPCC’s ‘Summary Reports’] of the scientists they associate themselves with – none of whom would surely claim to FULLY understand the myriad intricacies of our climate with its many positive and [far less talked about in AGW circles so it seems to me….] negative feedbacks), just what is the average lay-person out there like me supposed to believe is REALLY going on??

    Mike

  269. Guy:

    The UK paper The Independent today printed its results of an investigation into the suspicious datasets and graphs used in the programme. It also put its points to the programme’s director, Martin Durkin:

    http://news.independent.co.uk/environment/climate_change/article2355956.ece

    My personal favourite – when asked why the programme’s global temperature graph, credited as sourced by NASA, bore no relation to NASA’s actual temperature graph, Durkin replied “The original Nasa data was very wiggly-lined and we wanted the simplest line we could find”. That turned out to be out of date infromation compliled on a old climate sceptic website. So, er, not NASA then.

  270. Barton Paul Levenson:

    [[re postings 236, 237 and 238. I correctly and accurately said there is no evidence for man-made global warming; none, not any of any kind. The responses say there is some such evidence but cite no such evidence (which is not surprising because there is none). However, the responses do provide insults (as is usual from global warming fanatics).]]

    The evidence for anthropogenic global warming is as follows:

    1. CO2 has increased 40% since the industrial revolution started.

    2. The new CO2 is overwhelmingly from fossil fuels, not the biosphere, because it is deficient in carbon-14.

    3. More CO2 in the atmosphere warms the ground, all else held equal.

    4. Proposed alternatives such as Solar luminosity increase and modulation by galactic cosmic rays don’t stand up to scrutiny.

    What more evidence do you want? Just repeating “there’s no evidence” won’t make it so.

  271. Julian Flood:

    RE 259:>>We know for certain that the rise in CO2 is due to the burning of fossil fuels. Fossil-fuel carbon has a different isotopic composition than other sources; it’s depleted in C-13 (because its origin is organic plant matter) and depleted in C-14 (because it’s been buried underground for millions of years).>>

    I’m a bit worried about this certainty. I can think of three reasons for the Suess effect where the atmosphere shows more light isotope carnbon than expected — well, two-ish.: more C4 plankton; more C3 plankton converting to C4 metabolism; methanophages gettng their teeth into slightly warmer methane hydrates as ocean currents change in the deeps. The latter, BTW, might explain the CO2 rise after 800 years problem, if that is the ocean currents respond in a very slow rate to warming of the atmosphere. The C4 metabolism doesn’t fractionate carbon in the same way as C3, which means a falling dead C4 phyto takes with it into the depths an unexpectedly large amount of heavy isotopes — in effect it pumps down the heavy stuff.

    ‘It’s all we can think of’ is not a good response to answering a problem. ‘It’s the only thing we can think of at the moment. Anyone got any other ideas?’ is how I’d like this discussion to go, but too many people have nailed their flags to the mast and are determined to go down all guns blazing for that to be a realistic hope.

    I didn’t think much of the science on the Channel 4 programme, but I’m dubious of much of the stuff I’m told elsewhere. I’d like to see a few more ‘get your hands dirty’ scientists (ie real ones) being funded by both sides, not because I think either side is wrong, but because I don’t think science should be carried out by PR or in a massaged computer. Numbers, we need more real world numbers.

    You can do anything without numbers: I have invented a non-numerical explanation of global warming at http://www.floodswclimbers.co.uk. There are no numbers so I felt free to handwave to my heart’s content. However, it hangs together rather well. It even puts the blame, or most of it, on excessive oil consumption, car drivers and washing machines.

    JF

  272. Barton Paul Levenson:

    [[What percentage of CO2 emissions into the atmosphere are anthropogenic? The programme said it was quite a small proportion compared to the total emitted in other ways? Is that true? I have noticed the volcano effect being discounted but what about the rest?]]

    It’s true, much more is already circulating in the biosphere than human technology emits. But the natural carbon dioxide is balanced by things like the respiration/photosynthesis cycle. We’re adding extra that the system can’t take out in a reasonable amount of time, and as a result, CO2 has increased 40% since the industrial revolution began. And the new CO2 is mostly from fossil fuels, not the biosphere, because it’s deficient in carbon-14 (i.e., very old).

    [[The programme said that CO2 was only a small part of the greenhouse gases and that water vapour was much more important. Is this true and if so is it relevant?]]

    True yes, relevant no. H2O is a stronger greenhouse gas than CO2 and is present in greater quantities. But the amount of water vapor in the air is set by the ambient temperature and the relative humidity, not by anything we do. The average residence time of a molecule of water vapor in the atmosphere is 9 days; for carbon dioxide it’s more like 200 years. We could double water vapor tomorrow and almost all the excess would have rained out in less than a month. Carbon dioxide, however, will stay up there a long, long time.

  273. Barton Paul Levenson:

    [[1. So Richard Courtney is ‘a shill for the coal industry’. Fine. This means his papers need not be examined for their science? It is automatically wrong?]]

    What papers? All I’ve seen is posts here insulting climatologists.

  274. Angus:

    Can I suggest a resolution to the temperature CO2 lag debate. Concede the point that in the past, variations in the amount of solar energy impinging on earth have caused temperature changes. That the increases have caused CO2 to be released into the atmosphere. That the amount of CO2 released did not initiate global warming and it was susequently reabsorbed as the earth cooled.
    Instead, emphasize that we are at the top of one of these natural temperature cycles and at the same time we have released massive amounts of CO2 in the atmosphere, presumably with a lot more to follow in 800 years time. All the evidence suggests this was an incredibly bad idea. Incidentally most of the rebuttals appearing in the UK press are leaving out this point altogether and nit-picking about graphs. Also suggest Mr Gore clarifies this point in his film.

  275. Dan:

    re: 260. “2. Thousands of scientists now make a living from the billions of dollars available to study global warming. There is no money available from govt for the opposite.”

    This is a horribly biased, disingenuous point, probably intentional. The Bush adminstration is anything but willing to support climate research aside from things such as “clean coal technologies” (corporate handouts). In fact, the adminstration has put serious restrictions on the information government scientists can release/say about global warming. It has to be approved by political operatives first. That is common knowledge. The large sums of money are coming from the oil and coal corporations such as Exxon/Mobil who pay not only certain scientists (not many are climate researchers of course!) but PR firms to come up with misleading information, cherry-picked data, character assasinations, web blogs/postings, non peer-reviewed papers on the web and op-ed pages to simply confuse the public. Even if it means repeating items that have been long proven to be utterly false. Or making up new ones.

    Finally, please understand what “science” means. It is not a case of “opposite” research. The data are there for anyone to review. Science includes hypotheses, testing those hypotheses with data, analyzing the data for trends, publishing the results for peer-review, drawing conclusions and new hypotheses for further analyses and testing. You do not start with a conclusion or an “opposite” to prove a point. That is not science. Fortunately, climate research follows the scientific method. The science is strong and sound.

  276. Nick Gotts:

    Re #260 “Thousands of scientists now make a living from the billions of dollars available to study global warming. There is no money available from govt for the opposite.”

    Actually, I think money is generally made available to study climate change – “global warming” is a popular rather than a scientific term. However, setting that aside, the opposite of “global warming” is presumably “global cooling”. It now seems to be admitted even by most of those who deny that human activity is responsible that mean temperatures have increased in recent decades – i.e. that “global warming”, in the sense that phrase is generally used, has happened. Wouldn’t it be rather silly of any funder of science to fund extensive studies of global cooling, which (at least recently) hasn’t?

  277. Mike:

    Hi Chaps,

    Wikipedia has a section on the Channel 4 tripe and says it needs “cleanup”.

    http://en.wikipedia.org/wiki/The_Great_Global_Warming_Swindle

    I don’t know how to do that but if you do go for it.

    Regards

    Mike

  278. Dave Rado:

    re. #271, the climatologists whose articles are on this site are not being funded by any side, so why don’t you read their hard scientific articles on this site – there are hundreds – and the peer reviewed literature that they link to?

  279. Mike Forster:

    Apols in advance if this an old chestnut to say the least, but it often gets banded around amongst ordinary non-scientific folk out there anyway…… namely; what happened to all the talk by scientists a couple or three decades ago about us rapidly approaching a Mini-Ice Age?? What WAS all that about? The fact that such scientific musings were rampant not that long ago goes a long way to undermining what AGW scientists are saying NOW in the minds of many lay-people at least.

    Mike

  280. Jeffrey Davis:

    re: 271 and the source of atmospheric CO2

    So what happens to the CO2 that’s derived from the burning of fossil fuels? Does it just disappear? Occams Razor. We can account for the increase by calculating the amount of fossil fuels.

  281. tamino:

    Re: #268 (Mike Forster)

    Or do you mean that the oceans emit AND THEN RE-ABSORB 90 GT per year PLUS THEN they have to absorb half of the anthropogenic output ON TOP??

    That’s exactly what I mean.

    *Anthropogenic (human) CO2 contributes 6.5 Gt to the atmosphere per year.

    I think that’s correct.

    *Biomass absorbs 10 Gt per year, which is three times the net increase from fossil fuels.

    Correct, but biomass also emits that amount per year. That’s why the graph of CO2 concentration shows an annual cycle; plants take in CO2 during the northern-hemisphere growing season and release it back later in the year. Check out the Keeling Curve and you’ll see what I mean.

    *CO2 increase is levelling off due to increased plant growth absorbing CO2.

    Absolutely false. Look at the above graph again. Does it look like it’s levelling off? In fact since 2000 the CO2 concentration has been increasing more rapidly than ever — at about 2.1 ppmv/year.

    *CO2 increase is variable and in 1992 was zero.

    It is variable, and in 1992 was near zero. Many have attributed that to the collapse of the economy of the former Soviet Union.

    *Anthropogenic CO2 contributes 3% of the natural Carbon Cycle.
    This is less than 1% of the atmospheric reservoir of 750 Gt CO2.

    Less than 3% of the gross is easy to believe. What is not mentioned is that the other players in the cycle both emit and absorb, and are in equilibrium. Their NET contribution is zero (except the ocean, which is a net absorber now). It’s the human burning of fossil fuels that’s causing the increase.

    *The CO2 increase is following a 300 year global warming trend.

    If by “following” they mean “started after,” then OK. If by “following” they mean “is caused by,” then that’s just not true.

    *The well known Vostok Ice Core data shows that CO2 increases lag 600 years behind temperature increases

    This appears to be true, and there’s been quite a lot of discussion about that on this thread already.

    I for one find it astounding that anyone is still contending that the CO2 increase is not due to human activity. For at least 650,000 years, CO2 concentration never rose above 300 ppmv. In fact since the holocene (the last 11,000 years) it’s been very stable at around 280 ppmv — despite the large numbers involved in the carbon cycle that denialists like to point out dwarf human emissions. But those parts of the cycle are in equilibrium, taking as much as they give — how else could CO2 concentration be stable? Then — since the start of the industrial revolution — CO2 has risen by 35% to its present value just over 382 ppmv. And of course, there’s that isotope thing.

    Just how stupid do they think we are?

    Re: #271 (Julian Flood)

    Your alternatives might explain the C-13 depletion by an origin other than fossil fuels, but won’t explain the C-14 depletion.

  282. Eric Baum:

    If that is the extent of the rebuttal, I would think the film has made its case.
    If one is to believe in AGW, one needs evidence. The rebuttal concedes that there isn’t much. Unrebutted is the fact that the temperature CO2 correlation in the ice cores is not evidence for AGW, although it had been held out as convincing (at least by Gore), and that the temperature record of the 20th century is not much evidence for AGW, both because the temperature rise is completely unremarkable in historic context,
    and because the warming is punctuated by untimely drops. The rebuttal’s claim that this isn’t relevant is telling– it may not be disproof, but the assumption of the rebutters appears to be, we don’t need evidence for AGW. The fact that the models can match anything is one of the problems, not a victory! An attempt was made to rebut the claim of the film that the satellite and radisonde data is contradictory to AGW. The rebuttal skips over the fact (as I understand it) that everybody agrees agreement is lousy over the tropics– and the tropics comprise half the atmosphere. I’m left thinking the satellite data may not disprove AGW (as one scientist claimed in the film) but it seems apparent that it is mixed evidence. Also largely unrebutted is the films claim that solar/cosmic rays provide a better explanation for the evidence than GHG theories.

    Also unrebutted is the claim of the film that the IPCC is heavily politicized, and engaged in egregious violations of academic protocol. As a viewer of both film and this rebuttal, I am left wondering: are there in fact any serious scientists who would stand up and say in print they believe there is 90% confidence that humans have been responsible for more than half the warming?

    At my website, I have previously posted a summary of what I understand to be the changes in evidence and scientific understanding since 2001. It appears to me that they are rather damaging to the theory of AGW, so that our confidence should have declined rather than risen. If there is something I am missing, I would appreciate knowing what it is.

  283. Tim Dennell:

    “The Earth has been warming out of the Little Ice Age for the 300 years since then. Around 1700, Londoners used to have “Ice Fairs” on the frozen Thames each year. The last Ice Fair was held in 1814, and the Thames has not frozen solid since.”
    Richard S Courtney: Comment 233.

    Hubert Lamb and other historians have also found that the Thames also froze in 923 & 998.
    The Thames froze for seven weeks in 1061 and was completely frozen over during the severe winters of 1149/50, 1204/05, 1269/70 and 1281/82, 1309/10, 1407/08, 1409/10 1434/35, early 1506, 1513/14, 1516/17 and 1536/37. That’s throughout the entire Medieval Warm Period, however you wish to date its start and finish.
    The river Thames no longer freezes because of work done in the 19th century to widen the arches under London bridges and to improve ships’ passage along the river resulted in salty water extending further upstream and a faster flow rate along the river channel.

  284. Barton Paul Levenson:

    [[what happened to all the talk by scientists a couple or three decades ago about us rapidly approaching a Mini-Ice Age?? What WAS all that about? ]]

    The short answer is that it wasn’t by scientists, but by journalists. There was never a scientific consensus behind imminent global cooling.

  285. Andrew Robinson:

    Re 102: “There is NO controversy in the scientific community–just the normal process of consensus with some cranks who cling to dissent for their own contrarian reasons. It is the media and public who manufacture the controversy.”
    Ray Ladbury

    cf.

    “Dissent is the native activity of the scientist, and it has got him into a good deal of trouble in the last years. But if that is cut off, what is left will not be a scientist. And I doubt whether it will be a man.”
    Jacob Bronowski

    Most scientists go along with the idea that within science dissent/scepticism is how things move on: if there’s no controversy perhaps we should all start fearing for the climate science field itself.

    Finding consensus where it truly exists in a complex area can be a hard task, orders of magnitude harder when presenting a full analysis of all the peer reviewed literature as well: I’m not sure that the IPCC process is up to it.

    I’m not alone in that view. Call me IPCC-sceptic if you like.

    Long may climate science flourish, in breadth and richness, and in particular improve its explanatory and predictive powers.

  286. John L. McCormick:

    RE # 281

    Tamino, those factual retorts are simple, complete and most useful. Your comments are a resource.

  287. Barton Paul Levenson:

    [[Also largely unrebutted is the films claim that solar/cosmic rays provide a better explanation for the evidence than GHG theories. ]]

    This site has extensively rebutted both. Do a search on the site. In the meantime, here are some quick answers:

    The Sun is Doing It. This is wrong because

    1) The Solar constant hasn’t increased appreciably in 50 years (we’ve measured it from satellites). But global warming has taken off most noticeably in the last 30.

    2) Increased sunlight should heat the stratosphere, which intercepts sunlight first and absorbs it in ozone. Instead, the stratosphere is cooling, a discovery predicted by climate modellers on the basis of greenhouse gas warming of the surface.

    3) Increased sunlight should affect the equator most and the poles least, since higher latitudes have progressively less solar illumination (Lambert’s cosine law). Instead we see “polar amplification.” The poles are warming up quickest, another observation predicted by the modellers.

    Galactic Cosmic Rays are Doing It. No, because

    1) As with sunlight, the GCR level has no trend over the last fifty years.

    2) GCR may well affect cloud formation, but the data simply isn’t good enough to say exactly how yet.

    3) There are questions about the proxies used to estimate GCR intensity in the past. Until these are more reliable, the correlations Svensmark claims to have found are dubious.

  288. Steven Douglas:

    William and Gavin wrote:

    “The way they said this you would have thought that T and CO2 are anti-correlated; but if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its so small.”

    I know that was said only to illustrate that the two are not anti-correlated, but it reminded me of a skeptic who once said, “Let’s compare a 4 mm rise in the ocean levels next to the tiniest wave…”, as if that said anything about the scientific reality. This entire subject has to do with very small measurements and observed changes over some relatively long periods of time that carry some potentially huge (all sizes relative to a human perception scale) ramifications.

    What is questioned is the a lag, and whether correlation has any bearing on causation as well, and whether the explanations offered, with their underlying assumptions, are correct. The questions won’t go away, so why not keep all charts in perspective at all times? Anything that stops the pendulum.

    You also wrote:

    “The correct interpretation of this is well known: that there is a T-CO2 feedback: see RC again for more.”

    You say that “the correct interpretation” is well known, but then cite an article on your own site that attempts to explain the interpretation in layman’s terms. This is another example of begging the question with a circular reference. The article for the given link asserts that CO2 “could in fact” act as a feedback (the article was decidedly cautious in its initial wording, less so toward the end), but it was little more than a layman’s explanation, with plausible analogies for envisioning how this mechanism could work. Even then, I have some questions regarding its wording, to wit:

    In cited article cited above, Professor Severinghaus claims that “…the other 4200 years of warming could in fact have been caused by CO2…” (his wording becomes more definitive toward the end). The article also states unequivocally that CO2 could not have caused the first 1/6 (the first 800 out of 5000 initial years) of interglacial warming.

    Excerpts:

    1) …ice core studies have shown that CO2 starts to rise about 800 years … after Antarctic temperature during glacial terminations.

    2) …the lag shows … that CO2 did not cause the first 800 years of warming … CO2 could not have caused the first 1/6 of the warming.

    There was at least some CO2 present at the onset of glacial termination. Would not the atmospheric CO2 extant at least be considered a minor, even negligible contributing factor, right from the onset of the first 800 years of interglacial termination?

    In other words, how much CO2 must be present before it is considered an active feedback? A gnat hitting the windshield of a moving car still imparts energy, and has an effect, however indiscernible. Certainly CO2 could not have caused 100% of the initial warming, but was it not at least a contributing factor, however negligible? If so, why not state it this way? As it reads now, CO2 is sitting there like so much inactive, non-contributing dead weight for 800 years. What is there to suggest that whatever caused the first 800 years of warming (which Professor Severinghaus said could not have been CO2) could not also have been the primary forcing for the latter 4,200 years of warming as well?

    Also, Professor Severinghaus wrote, “From model estimates, CO2 (along with other greenhouse gases CH4 and N2O) causes about half of the full glacial-to-interglacial warming.”

    If he had included sunlight and water vapor (the granddaddy of them all) he would have hit the trifecta. Since excess CO2 is the main focus of blame, why lump it in with other GHG in the article? What was the reason for that? Why not just give an estimate (based on model estimates or otherwise) that breaks out CO2’s estimated contribution to warmings?

  289. Angus:

    Can anyone comment on my suggestion in 274, the explanations of the lag given are the weakest part of your case. By conceding that CO2 did not start the warming and that it perhaps only slowed down the cooling you could end this topic.

  290. Ken Winters:

    Here’s another critique of the movie by John Houghton (head of the IPCC from 1988 – 2002):

    http://www.jri.org.uk/index.php?option=com_content&task=view&id=137&Itemid=83

  291. Ike Solem:

    Re#288, Stephen, you’re missing a basic point – even at the height of the glacial period, CO2 played a significant role in warming the planet, as compared to say, the temperature on the Moon (-273C on the dark side).

    You say: “As it reads now, CO2 is sitting there like so much inactive, non-contributing dead weight for 800 years. What is there to suggest that whatever caused the first 800 years of warming (which Professor Severinghaus said could not have been CO2) could not also have been the primary forcing for the latter 4,200 years of warming as well?”

    Well, that’s because the effect of the Milankovitch cycles (eccentricity, precession, and axial tilt) are fairly minimal, and are related to the seasonal timing and location of solar inputs, not on changes in the total solar energy recieved at Earth’s surface.

    For example, see Simulating the amplification of orbital forcing by ocean feedbacks in the last glaciation, Khodri et al Nature 2001:

    According to Milankovitch theory, the lower summer insolation at high latitudes about 115,000 years ago allowed winter snow to persist throughout summer, leading to ice-sheet build-up and glaciation. But attempts to simulate the last glaciation using global atmospheric models have failed to produce this outcome when forced by insolation changes only. These results point towards the importance of feedback effects-for example, through changes in vegetation or the ocean circulation-for the amplification of solar forcing. Here we present a fully coupled ocean-atmosphere model of the last glaciation that produces a build-up of perennial snow cover at known locations of ice sheets during this period. We show that ocean feedbacks lead to a cooling of the high northern latitudes, along with an increase in atmospheric moisture transport from the Equator to the poles. These changes agree with available geological data and, together, they lead to an increased delivery of snow to high northern latitudes. The mechanism we present explains the onset of glaciation-which would be amplified by changes in vegetation-in response to weak orbital forcing.

    As far as why to include the full component of greenhouse gases, that’s because the question is: how do changes in the atmospheric composition affect the planet’s surface temperature? In this case the correlation between temperature and atmospheric composition has a clear mechanism that relates the two: the absorption and re-radiation of infrared energy by greenhouse gases.

    There are many, many processes that show such feedback effects – consider striking a match (a small amount of friction leads to a large amount of heat being produced), starting an avalanche with a small rock, etc.

  292. P. Lewis:

    Can anyone comment on my suggestion in 274, the explanations of the lag given are the weakest part of your case. By conceding that CO2 did not start the warming and that it perhaps only slowed down the cooling you could end this topic.

    Comment by Angus

    Angus, do you think that the professional climatologists, palaeoclimatologists and atmospheric physicists hereabouts have never heard of Milankovich and the causes of ice ages?

    What! No, they haven’t!

    Well, glory be! You appear to be correct then (in a funny, distorted kind of way), “that CO2 did not start the warming and that it perhaps only slowed down the cooling” … oh, and added to the warming.

  293. Mike Forster:

    All comments in response to my posts above are most appreciated. Thank you for helping to better inform me.

    I guess it all boils down to:
    1. CO2 has risen from 280-380ppm during the last 150 years. For the previous 650,000 years atmospheric CO2 has held steady at between 180 and 280ppm.
    2. Average global surface temperature has risen 0.8C during the last 150 years.

    (I’m here ignoring whether or not solar and/or cosmic forcing accounts for much, if any, of the said temperature increase. The concensus – at least here on this blog – is that they do not.)

    As such – and admittedly stating the obvious to you folks here but at the same time clarifying things in my own lay-person’s mind – the REAL issue here then IS: Just how much of the observed increase in temperature is due to anthropogenic CO2 output??

    That’s got to be a really tough one to answer with any certainty. SURELY the climate has ALWAYS been liable to temperature swings a couple of degrees one way or the other on a century and milennium basis.

    For example and from:

    http://www.nationalcenter.org/NPA194.html

    [lengthy excerpt eliminated. readers can go to this link if they like. But lets not pretend this is honest information; this is an industry-funded disinformation site]

    Mike

  294. tamino:

    Re: #289 (Angus)

    Can anyone comment on my suggestion in 274, the explanations of the lag given are the weakest part of your case. By conceding that CO2 did not start the warming and that it perhaps only slowed down the cooling you could end this topic.

    I think everybody who knows (including the moderators) agrees that CO2 did not start the warming. But I doubt that will end this topic. Skeptics have perceived a weakness, and they’re going to milk it for all they think it’s worth.

    I disagree that it’s the weakest part of the case. It’s not really much of the case, for one thing. For another thing, the only ones I’m aware of who ever seriously claimed that CO2 was the sole cause of warming during deglaciations are the skeptics — who set it up as a straw man argument. But it is (a small) part of the case, because without greenhouse-gas amplification we can’t explain the large warming during deglaciation.

    Re: #292 (P. Lewis)

    I see no reason to be anything less than grateful to Angus. As far as I can see, he has made no denialist statements, hasn’t spread any misinformation, and he has correctly identified what is at least perceived as the weak link in the chain of reasoning. We should be paying close attention.

  295. Jappo:

    I have looked for comments regarding the experiment last Year in which Prof Henrik Svensmark successfully generated cloud condensation nuclei by bombarding a replica atmosphere with ionising radiation. Why does it appear that this is being ignored by everyone?

  296. Hank Roberts:

    > Why does it appear that this is being ignored by everyone?

    Because you don’t look? Use Google? Type it into the search box at the top of each page.

  297. Richard S Courtney:

    Re 270:

    A nice hypothesis but there is no evidence for it. Indeed, the posting admits that it would only hold if “all other things were the same”. But in a complex system such as climate all other things will not be the same. Like all GW propoganda, posting 270 cliams the hypothesis of man-made global warming is proof of itself!

    There is no evidence for man-made global warming and making a mantra of the hypothesis of man-made global warming cannot change that.

    Also, the carbon-14 change is far too great for it to be explained by the anthropogenic emission. Science is about interpretation of evidence: it is not the distortion of facts to suite the purpose of advocacy (be it of global warming or anything else).

    And why is it acceptable to put personal insults of me on this web site but my rebuttals are censored?

    Richard

  298. Nick Gotts:

    Re #295 Because you haven’t bothered to look. Try searching for “Svensmark” on this site.

  299. James:

    Re #289: [Can anyone comment on my suggestion in 274, the explanations of the lag given are the weakest part of your case. By conceding that CO2 did not start the warming and that it perhaps only slowed down the cooling you could end this topic.]

    Explanations of the lag aren’t the weakest part of the case: they aren’t part of the case at all. The case for AGW doesn’t depend on records of past climate changes; it comes from the known behavior of CO2, and the indisputable (except by blithering idiots) fact that humans have put a lot of it in the atmosphere over the last century or so.

    At its most basic, AGW theory is no more complicated than saying you’ll be warmer if you put a sweater on, and that doesn’t depend on what your granny told you, does it?

    Saying so certainly wouldn’t be a concession: it’s been part of what we might call the standard AGW model all along.

    I don’t think it would end the topic: I know I’ve given my own explanation (over-simplified and non-expert as it may be) several times in the last few days; others have tried to explain it as well. If it’s not getting through, either we all lack the ability to explain it clearly enough, or the readers aren’t interested in trying to understand.

  300. tamino:

    Re: #293 (Mike Forster)

    As such – and admittedly stating the obvious to you folks here but at the same time clarifying things in my own lay-person’s mind – the REAL issue here then IS: Just how much of the observed increase in temperature is due to anthropogenic CO2 output??

    The best numerical estimates I’ve seen of the magnitude of the various contributions to global warming are the “forcings” data from NASA/GISS. You can download the data here. The colums are:

    W-M_GHGs = well-mixed greenhouse gases
    O3 = ozone
    StratH2O = stratospheric water vapor
    Solar = solar variation
    LandUse = land-use changes
    SnowAlb = snow albedo
    StratAer = stratospheric aerosols
    BC = black carbon
    ReflAer = reflective aerosols
    AIE = aerosol indirect effect

    All forcings are given in watts per square meter, and the zero point is taken as the value in 1880. Positive values imply warming relative to 1880 values, negative value imply cooling.

    That’s got to be a really tough one to answer with any certainty. SURELY the climate has ALWAYS been liable to temperature swings a couple of degrees one way or the other on a century and milennium basis

    That’s just plain incorrect, but it’s one of the most common lies told by denialists. Take a look at the many temperature reconstructions and it’s plain to see that “a couple of degrees” is way outside the norm.

  301. Hank Roberts:

    Speaking only as another reader here.

    It may not be you — the name has a track record online — and it’s not clear which Richard S. Courtney you are, whether you’re someone new using the same name or one of those who’s easy to find by searching climate postings.

    I trust our hosts check that postings under this name are coming from the same IP or a limited few, so nobody’s spoofing the name here to sow confusion (it happens, trolling is a sport).

    But, Google; several (apparently different) people using the name posted to a lot of climate sites, and there’s been a real effort to figure out why it’s so hard to know who RSC really is.

    Can you clarify who you are? are you the Oxford PhD? The academic in either of two American universities?

  302. Mike Forster:

    I notice from links from what you folks here might call industry-driven disinformation websites that some Russian (particularly solar physicists) and Chinese scientists have very recently published articles in scientific journals (e.g. Chinese scientists Lin Zhen-Shan & Sun Xian in Meteorol Atmos Phys 95, 115-121 (2007)) claiming that global COOLING will occur in the early and middle of the 21st Century….. Is it a mistruth that such articles ARE being published in SJs? If not, then do the articles themselves merely comprise misinformation of little or no merit?

  303. Julian Flood:

    Re 271/281

    When carbon is fractionated by a biological process, the heavier isotopes are both effected — C14 more so than 13 because it’s even less user friendly. So it might be able to differentiate my process out by checking change of C14/13 ratio. Unfortunately, I doubt if the accuracy is up to it yet. So the signal seen is a drop in the C13/C12 ratio and C12/C14.

    C14 in hydrates — just how old are the clathrate deposits, does anyone know?

    JF

  304. angus:

    Thanks tamino for your support. I really do think you should update Prof Severinghaus’s piece about the lag. It is vague to say the least and is the first place I hit when googling for information.
    Is it a problem to say that in the past CO2 levels lagged temperature rise in a natural cycle? The real problem lies in injecting a massive amount of carbon when we are at the top of that cycle.

  305. Hank Roberts:

    http://www.whoi.edu/science/MCG/dept/highlights/project_sediment.html

    “… combustion products of environmental concern include nitrous oxides, sulfur dioxide, soot, and polycyclic aromatic hydrocarbons (PAH). Several of these species (such as sulfur dioxide and soot) may also play an important role in climate change, while others (such as PAH) impact environmental quality through their toxicological properties.

    “It is important, therefore, to distinguish and quantify emissions from different combustion processes. Developing temporal records that document amounts and sources of combustion products will help us assess past and present emissions and predict future trends. …

    “…. Carbon 14 abundances of the PAH are expressed in terms of “fraction modern”, where a value of 1 is equivalent to 100 percent modern carbon, and 0 corresponds to 100 percent fossil carbon. Carbon 14 measurements on pyrogenic PAH yielded a fraction modern value of about 0.9 in the early 1800s, and decreased to about 0.5 in the mid-1900s. This trend is consistent with increasing utilization of fossil fuels over this time period. … the fraction modern value for the pyrogenic PAH in the uppermost portion of the core (circa 1950) is surprisingly high. This interval coincided with the maximum utilization of coal as an energy source, after which oil and gas became the preferred fuels.”

  306. tamino:

    Re: #302 (Mike Forster)

    … Is it a mistruth that such articles ARE being published in SJs? If not, then do the articles themselves merely comprise misinformation of little or no merit?

    These articles (at least the one by Lin Zhen-Shan & Sun Xian) are indeed published in scientific journals. Take note, this belies the claim that dissenting views are shut out of scientific journals.

    Scientific journals do not select what gets published based on whether or not the paper agrees with the concensus view. They are selected based on whether or not they conform to proper methodology and accurate data. For some of the biggest journals, there are so many papers submitted that they must be very selective, so non-concensus views are less represented than in other journals — but if your paper has proper methodology and correct data, you can almost always find a journal to publish it, no matter how far outside the concensus your viewpoint may be.

    I’ve seen the paper by Lin Zhen-Shan & Sun Xian, and it my opinion it is without merit. Their paper isn’t about physics or climate science, but about a mathematical analysis of temperature time series. In my opinion (and this is my field) they apply a rather dicey technique, and then use it to extrapolate into the future in a way which is not justified by either the data or the mathematics.

    But again, scientific journals aren’t about choosing based on the concensus view or limiting papers to what is universally accepted; they’re about presenting a number of different viewpoints so that readers can decide for themselves what has merit and what doesn’t.

  307. Hank Roberts:

    > how old are the clathrate deposits?

    I asked the same question a while back; there’s a deeper question (how old is the methane _in_ the clathrates) because the clathrates may be a transition material produced as methane moves _up_ from deep and very old sources, and interacts with cold water in seafloor sediments.

    Look for geological info on “pingo” structures, which the gas industry is already talking about mining for methane. The geologists up til a few years ago said they were caused by freezing of ice under sediment, but now they’re popping up — er, being found — whichever — in shallow ocean along the continental shelf.

    I hope an expert here will comment on what’s being found out — are pingos recent, caused at the end of the ice age by the peak warming, perhaps? If so we may be provoking a new round of them by keeping temperature from declining after the last peak 10-11,000 years ago.

    One tangentially helpful cite:
    http://serc.carleton.edu/resources/2574.html
    The biogeochemical consequences of the mid-Cretaceous superplume
    http://www.jhu.edu/~eps/faculty/jahren/Jahren2002.pdf

    Jahren A., Department of Earth and Planetary Sciences, Johns Hopkins University

    This journal article (published in the Journal of Geodynamics) proposes that large amounts of carbon were liberated from submarine methane clathrate deposits during the mid-Cretaceous superplume event.

    Evidence for this hypothesis is based on carbon isotope records of marine carbonates, marine organisms, and terrestrial plants.

    The author speculates that possible effects of this disruption on the global carbon cycle may have included widespread oceanic anoxia and changes in land plants at mid- to high-latitudes.

  308. David B. Benson:

    Re #293: Mike Forster — In a simple, orbital forcing theory way, more than 100% of the current warming is anthropogenic. According to orbital forcing, the golobal temperature should be in a very gentle decrease ever since 8000 years ago, leading to an attempt at a stade (big ice sheets) in about another 20,000 years.

  309. ramalama:

    someone wrote:

    “Explanations of the lag aren’t the weakest part of the case: they aren’t part of the case at all. The case for AGW doesn’t depend on records of past climate changes; it comes from the known behavior of CO2, and the indisputable (except by blithering idiots) fact that humans have put a lot of it in the atmosphere over the last century or so.

    At its most basic, AGW theory is no more complicated than saying you’ll be warmer if you put a sweater on, and that doesn’t depend on what your granny told you, does it?”

    Gosh, NOW I get it!!!

    [rest edited out….we probably shouldn’t have let this first comment through w/out editing, but that’s no excuse for fanning the flame war. Folks, if you can’t be civil, your posts won’t make it through]

  310. Sean Ferguson:

    My first impression after having watched both ‘An Inconvenient Truth’ and the channel 4 GGWS is that climatology seems to lack the sort of experimental modalities and valid, reliable criteria for discerning causal relationships that some other fields have obtained – say microbiology with its Koch’s Postulates.

    Statistical significance is all well and good, but meaningless if your experimental design doesn’t equip you to identify a casual relationship. What is climatology’s equivalent to the RCT? If there is none, isn’t the positive feedback loop argument to explain away the time lag between temperature rise and CO2 rise just more conjecture about causation? In fact, doesn’t the feedback argument presuppose that CO2 rise was what caused the temperature rise in the first place? That being the case, the parsimonious (even if incorrect) explanation for the time lag seems to be something akin to what Carl Wunsch himself proffers in the GGWS documentary.

    Please answer if you’re equipped to discuss experimental design. Thanks.

  311. James:

    Re #295: [I have looked for comments regarding the experiment last Year in which Prof Henrik Svensmark successfully generated cloud condensation nuclei by bombarding a replica atmosphere with ionising radiation. Why does it appear that this is being ignored by everyone?]

    In addition to the other responses, because it’s rather old news. The same principle is used in cloud chambers, which have been around for more than a century. See here:

    http://en.wikipedia.org/wiki/Cloud_chamber

    If you’re really interested, there’s a link or two from there that give instructions on how to build your own.

  312. Mike Forster:

    I’ve just seen/read the transcript from the BBC Horizon programme of January 2005 about ‘Global Dimming’.

    http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dimming_trans.shtml

    It does NOT make for reassuring reading.

    I’d accordingly be interested to hear what any of you AGW denialists out there have to say about the surmisals made as per the abovementioned piece…….

    What’s the current opinion within the wider scientific community as regards just how bad AGW could get if we clean up pollution particles WITHOUT at the same time drastically lowering anthropogenic CO2 emissions? One assertion in the programme was that temperatures could go up by as much as 10C by 2100 IF global dimming is eliminated and anthropogenic CO2 amissions not drastically cut…… Is this view still currently shared by many respected climatologists? Or has new evidence emerged that significantly changes the scenario?

    As an aside, are there any estimates out there as to how long the Greenland ice sheet would take to melt if temperatures increased by 5-10C by 2100?

  313. Joe Rosenfels:

    Left field: Methans quote: http://en.wikipedia.org/wiki/Methane “Methane in the Earth’s atmosphere is an important greenhouse gas with a global warming potential of 23 over a 100 year period. This means that a 1 tonne methane emission will have 23 times the impact on temperature of a 1 tonne carbon dioxide emission during the following 100 years”

    The focus should be to reduce methane and worry less about c02, but that would not be politically correct?

  314. tamino:

    Re: #309 (Joe Rosenfels)

    The same wikipedia article you reference also states that the atmosphere contains 220 times as much CO2 as methane. So the total climate forcing from CO2 is greater than that from methane (as is well documented in the IPCC reports).

    But methane is the 2nd-most potent antrhopogenic greenhouse gas (after CO2), as is alwo well documented in the IPCC reports, and is a subject of great concern.

    I fail to see why reducing methane would not be “politically correct.”

  315. Hank Roberts:

    >309, Joe Rosenfels

    Hey, Joe — guess who you agree with about that?

    http://www.nybooks.com/articles/19131

    ” … absolute reduction of the principal non-CO2agents of global warming, particularly emissions of methane gas. Such methane emissions are not only the second-largest human contribution to climate change but also the main cause of an increase in ozoneâ��the third-largest human-produced greenhouse gasâ��in the troposphere, the lowest part of the Earth’s atmosphere. Practical methods can be used to reduce human sources of methane emission, for example, at coal mines, landfills, and waste management facilities. …

    “If both the slowdown in CO2 emissions and reductions in non-CO2 emissions called for by the alternative scenario are achieved, release of “frozen methane” should be moderate, judging from prior interglacial periods that were warmer than today by one or two degrees Fahrenheit.”

  316. Ike Solem:

    RE#297
    Richard, you say that “the carbon-14 change is far too great for it to be explained by the anthropogenic emission.” without giving any references or supporting information.

    The CO2 carbon 14 issue was addressed some 50 years ago: see the excellent online guide to the history of the science at http://www.aip.org/history/climate/co2.htm#L_0244 :

    “Fortunately, scientists could now track the movements of carbon with a new tool – the radioactive isotope carbon-14. This isotope is created by cosmic rays in the upper atmosphere and then decays over millennia. The carbon in ancient coal and oil is so old that it entirely lacks the radioactive isotope. In 1955, the chemist Hans Suess reported that he had detected this fossil carbon in the atmosphere.

    The amount that Suess measured in the atmosphere was barely one percent, a fraction so low that he concluded that the oceans were indeed taking up most of the carbon that came from burning fossil fuels. A decade would pass before he reported more accurate studies, which showed a far higher fraction of fossil carbon. Yet already in 1955 it was evident that Suess’s data were preliminary and insecure. The important thing he had demonstrated was that fossil carbon really was showing up in the atmosphere.”

    The real issue is how the oceans will respond to warming, and whether they’ll continue to take up as much CO2 as in the past.

    RE#309, it’s the abundance of CO2, and the fact that methane in the atmosphere gets converted to CO2 over time (sunlight + methane + oxygen (OH-, etc) -> CO, CO2). The problem is the use of fossil fuels, which are ancient carbon – cows and other methane-producing ruminants are very different in that their carbon source is plant photosynthesis, not buried deposits; thus is you measure methane coming out of cows (some job that would be..) you’d find that it has an identical C-14 content to the atmosphere, while fossil methane deposits (natural gas) are completely depleted in C-14. Still, producing methane instead of CO2 increases the radiative forcing; but the 4th IPCC summary states that the forcing due to anthropogenic methane is about 1/4 that due to anthropogenic CO2. Atmospheric methane has also apparently (temporarily?) stabilized over the past few years, unlike CO2: http://www.sciencedaily.com/releases/2006/09/060927201651.htm

  317. Dave Rado:

    1) There is approximately 220 times as much CO2 in the Earth’s atmosphere as methane.
    http://en.wikipedia.org/wiki/Methane#Methane_in_Earth.27s_atmosphere

    2) CO2 remains in the atmosphere on average for around 200 years, whereas methane remains in the atmosphere on average for around 10 years; so methane’s *overall* greenhouse effect over the cycle is not much higher than that of CO2.

    3) We are not currently releasing methane into the atmosphere at anything like the rate that we are releasing CO2 into the atmosphere – in fact there is no currently significant trend in atmospheric methane levels, which means it is not currently contributing anything at all to global warming.

    4) On the other hand, there is a very real danger than permafrost melting resulting from global warming, see:
    http://environment.newscientist.com/article/mg18725124.500.html
    … may well eventually cause methane to rise at a sufficiently fast rate to cause a chain reaction, where global warming causes methane to be released, which causes more warming, which causes more methane to be released, and so on, until it gets out of control and the temperature starts to soar. This could then trigger a second chain reaction, because when the temperature reaches a certain level, methane trapped in ice-like structures called clathrates at the bottom of the oceans could start to be released rapidly into the atmosphere. There is 3,000 times as much methane trapped in clathrates as there is in the atmosphere.

    There is very strong evidence that this has happened before – see:
    http://en.wikipedia.org/wiki/Paleocene-Eocene_Thermal_Maximum
    http://www.eurekalert.org/pub_releases/2003-10/uoc–neo102003.php
    http://en.wikipedia.org/wiki/Permian-Triassic_extinction_event

    So in other words, methane is not currently contributing to global warming; but if we don’t start to reduce our CO2 emissions soon, there is a genuine risk that methane may start to contribute to global warming in the future; and if that does happen, it would probably be extremely serious, to the extent that the highest end climate projections could start to look plausible.

    See also:

    http://www.realclimate.org/index.php?p=227

  318. Gareth:

    …measure methane coming out of cows (some job that would be…)

    We do that all the time down here (NZ). Here’s a picture of some sheep wearing methane measurement gear. I’ve had a chat with methane measurers – apparently, you can detect the methane plume from a dairy farm miles downwind.

    Suggestions that cutting methane emissions is a quick and “easy” way to reduce forcing don’t work for us, where half of our emissions are from agriculture. Probably not easy if you grow a lot of rice, either.

  319. john graves:

    Well then. 318 comments in just five days.Certainly stirred up the hornets nest then, didn’t we?

  320. P. Lewis:

    Re: #294 (tamino)
    Hi Tamino

    I genuinely admire the outwardly serene way you can answer what I see as a lot of plain ignorance, misunderstanding and outright distortion. It is a gift. Keep up it up.

    Now it might be a personality disorder, but I ain’t made like that, I’m sorry. Up to a point, I can be as amiable and helpful (and as serene) as you in replies to anyone who shows genuine interest (and I don’t mind if it’s a contrary point of view to mine to argue; indeed, here and elsewhere I’ve stood up for contrarians when ad hominems have been visited io). But Angus’s point (misunderstanding?) has been covered ad nauseum amongst the replies already on this thread (and elsewhere recently), and it is covered and referenced in the OP and accessed easily through the FAQ.

    I suppose it’s how the question is asked, or perceived as being asked. To my mind, there’s a way of asking questions if you would like things explained more clearly. I didn’t (and still don’t) see that in Angus’s first two messages.

    With regard to my reply to Angus and surmising that he was taking a contrarian view. Far from it. There was sufficient evidence in his #274 post to form the view that Angus did not take that position. It was penned purposely with the intent of conveying disbelief that Angus could entertain that all the professional climate scientists have overlooked this issue (and yes, I know, they’re not all-knowing gods who must be obeyed without question; and that not even the great GS himself gets it right all the time) and that CO2 lag was not an issue. I can take the distortion and misunderstanding, but there is a pervading arrogance abroad that a poster knows more than the professionals whose job climate study is (you see a similar situation on physics discussion boards in relation to attacks on Einstein’s relativity theories: “everyone” has spotted the errors of Einstein). I find it infuriating, on their behalf.

    ********************************************
    Re: #304 (Angus)
    But, in #304, I sense Angus’s tone is more correct (to my sensibilities, anyway):

    Is it a problem to say that in the past CO2 levels lagged temperature rise in a natural cycle?

    to which, Angus, once again (but less sarcastically), I would reply “no”:

    Anti-AGW lobby: “CO2 lags. Wow, that’ll shoot that there pro-AGW lobby down in flames! Let’s see ‘em get out of that one.”
    Pro-AGW lobby: “CO2 lags. Yes, we know. So what! It’s factored in to our understanding.”

    The lag out of ice ages is really a non-issue wrt to 21st century AGW, and it’s not an issue palaeoclimate-wise (which is not to say that there isn’t science in looking at that lag, or at other aspects of the forcing that led to ice waxing and waning).

    Oh, and Angus, Prof. Severinghaus is not part of RC so far as I can see. He either offered to or was asked to contribute a piece with regard to his group’s peer-reviewed work in gas analysis in ice cores and its application to palaeoclimate studies. Presumably, that study and others of its ilk are/will be contained somewhere within the body of the IPCC AR4.

    To Angus, try to re-read the RC article if you can and read Caillon, Severinghaus, et al. (2003): Timing of atmospheric CO2 and Antarctic temperature changes across Termination III. Science 299: 1728-1731, on which the RC article was based. And then read this (fairly typical) distortion, this time by the Association of British Drivers:

    The most recent study available covering this theme is that of Caillon et al. (2003), who focused on an isotope of argon (40Ar) that can be taken as a climate proxy, thus providing constraints about the relative timing of CO2 shifts and climate change. Air bubbles in the Vostok ice core over the period that comprises what is called Glacial Termination III – which occurred 240,000 years BP – were studied. The result of their painstaking analysis was that “the CO2 increase lagged behind Antarctic deglacial warming by 800 +/- 200 years.” This finding, in the words of Caillon et al., confirms that CO2 is not the forcing that drives the climatic system. Anthropogenic climate change (man-made global warming theory), based on the claimed impact of CO2 emissions from transport and industry, is stone cold dead.

    and then spot what Caillon et al. did say and didn’t say.

  321. P. Lewis:

    Re #320

    Oops! Hit the “Post” button by mistake. Duh!

    “io” was meant to have been “upon them”.

    And “Oh, and Angus, Prof. Severinghaus” was meant to have read “Oh, and Angus, if you were wondering (and someone was), Prof. Severinghaus”.

    Sorry folks (need a recall button).

  322. Joe Rosenfels:

    Perhaps we should power our cars with methane? http://www.truehealth.org/volvomethanecars.html

    One more question when reviewing global temperatures, on a year to year basis, temperatures do not increase some years they actual decrease: http://en.wikipedia.org/wiki/Image:Instrumental_Temperature_Record.png
    This I find interesting as c02 only ever increases: http://en.wikipedia.org/wiki/Image:Mauna_Loa_Carbon_Dioxide.png

    Any comments, cheers.

  323. W Low:

    I’ve read in various places on the Internet that CO2 was 4400ppm during the Ordovician period. If that is true, people must wonder whether the Earth was 12 times as warm as well, and, if not, then why wasn’t temperature in step with CO2. The implication one may derive is that temp isn’t (always) in step with CO2 so why can’t the world at least wait till it reaches that amount before we get worried. This is the only Global Warming “controversy” issue that I have not seen addressed here of which I am aware.

  324. dhogaza:

    One more question when reviewing global temperatures, on a year to year basis, temperatures do not increase some years they actual decrease: http://en.wikipedia.org/wiki/Image:Instrumental_Temperature_Record.png
    This I find interesting as c02 only ever increases: http://en.wikipedia.org/wiki/Image:Mauna_Loa_Carbon_Dioxide.png

    Well, quite clearly, as the climate scientists here and elsewhere patiently point out over and over again, CO2 isn’t the only thing out there that impacts temperature.

    You can google this site, you know? Learn before you post, etc etc?

  325. Angus:

    All I have been trying to say is that you guys should put up a cogent explanation (ie understood by non-climatologists) as to why the historical record is not relevant to AGW. The dissenters will just keep pointing to the lag and say CO2 is not responsible for our present predicament, Mr Gore’s presentation of the ice core data in his movie opened a door for channel 4, I like may others wanted to know the truth on this point, Prof Severinghaus’s piece does not do the job.
    Here would be my interpretation (forgive a non climatologist)
    1) Ice ages finish when the solar energy impinging on the earth causes temperatures to start to rise.
    2) Over a period of time CO2 is released into the atmosphere, peaking about 800 years later.
    3) As the solar energy falls the CO2 greenhouse effect acts to compensate this and a complex feedback effect causes the temperature to oscillate back down to the previous levels.
    4) This natural process has been endangered by injecting vast amounts of carbon at the top of the cycle.

  326. Timmothy K.:

    Via Carl Wunsch’s Climate Change site @ http://www.royalsoc.ac.uk/page.asp?id=4688&tip=1

    People ask “is it clear that human activity is directly responsible for climate change?” The context for answering this question must be another question: to what extent can the climate change all by itself?

    The answer to the alternative question is: “a very great deal.”

  327. BarbieDoll Moment:

    RE: …”As an aside, are there any estimates out there as to how long the Greenland ice sheet would take to melt if temperatures increased by 5-10C by 2100? “…

    Here are two actual current assessments of the sheet which
    one could possibly work with to derive some type of idea
    that it doesn’t require that type of temperature change
    for the sheets to significantly melt, and in turn,
    raise water levels.

    Rapid volume loss from two East Greenland outlet glaciers quantified using repeat stereo satellite imagery
    Geophysical Research Letters 34 (5), 05503 (2007)
    http://dx.doi.org/10.1029/2006gl028982
    “The coastal portions of Kangerdlugssuaq and Helheim glaciers in southeast Greenland lost at least 51 ± 8 km3 yr^-1 of ice between 2001-2006 due to thinning and retreat, according to an analysis of sequential digital elevation models (DEMs) derived from stereo ASTER satellite imagery.”…”Extrapolation of the measured data to the ice divides yields an estimated combined catchment volume loss of ~122 ± 30 km3 yr^-1, which accounts for half the total mass loss from the ice sheet reported in recent studies. These catchment-wide volume losses contributed ~0.31 ± 0.07 mm yr^-1 to global sea level rise over the 5-year observation period with the coastal regions alone contributing at least 0.1 ± 0.02 mm yr^-1.

    The 1979-2005 Greenland ice sheet melt extent from passive microwave data using an improved version of the melt retrieval XPGR algorithm
    Geophysical Research Letters 34 (5), 05502 (2007)
    http://dx.doi.org/10.1029/2006gl028787
    “Analysis of passive microwave satellite observations over the Greenland ice sheet reveals a significant increase in surface melt over the period 1979-2005. Since 1979, the total melt area was found to have increased by +1.22 x 10^7 km2.”…“Finally, the observed melt acceleration over the Greenland ice sheet is highly correlated with both Greenland and global warming suggesting a continuing surface melt increase in the future.

  328. Leo:

    I have to agree with Angus (#325) that the illuminated amongst you are doing the rest of us no favours in trying to get a grip on this.

    If CO2 is causing most of the global warming, we need to be told how that has been shown in clear, unambiguous terms.

    What hard data shows that CO2 increases T rather than the other way round?

    Why do some of you dismiss the lag between T and CO2 as irrelevant?

    Where are the analyses of the ice-core data that Durkin used?

    Why are they wrong?

    I’ve been following this thread since it started and am now frankly more confused than when I started. Perhaps a week isn’t long enough to get one’s head round all this from scratch, but please guys, give us a fighting chance.

  329. Angus:

    Now Leo, you are only going to set them off again! CO2 is a greenhouse gas- proven, its forcing effect depends how much of it is the atmosphere, historically it appears it was insufficent to cause a problem, a natural feedback cycle occurred and temperatures oscillated but came back to “normal”.In a geological heartbeat we have increased that amount by a very large percentage, history no longer applies.

  330. Dave Rado:

    #328

    If CO2 is causing most of the global warming, we need to be told how that has been shown in clear, unambiguous terms

    In science, the way things work and have always worked is: you start with some evidence, you then come up with a theory to explain that evidence, you then test that theory using real world observations and make sure it fully explains *all* observations and that no observations fatally contradict the theory; and if any does, you modify the theory where needed. In the case of the greenhouse effect, the evidence and theory for that is more than 150 years old:
    http://en.wikipedia.org/wiki/Greenhouse_gas
    and has been tested by millions of real world observations without any evidence contracting the theory, so is as solid as Newton’s laws are.

    In terms of testing the evidence against the theory, I can’t list here all of the millions of strands of evidence that all corroborate the theory but there *are* literally millions of strands, and there are none that contradict it. The proof of how incredibly well the theory matches up with the real observed evidence is here:
    http://www.globalwarmingart.com/wiki/Image:Climate_Change_Attribution_png
    and here:
    http://www.grida.no/climate/ipcc_tar/wg1/figspm-4.htm

    What hard data shows that CO2 increases T rather than the other way round?

    It’s not “rather than the other way round”. It works *both ways* round. The fact that increasing the number of chickens in a coup leads to an eventual increase in the number of eggs is not evidence that increasing the number of eggs wouldn’t also lead to an eventual increase in the number of chickens.

    CO2 in the atmosphere doesn’t just spontaneously increase without any cause: in the past it increased very slowly (over many hundreds of years) due to warming triggered initially by changes in the earth’s orbital tilt:
    http://en.wikipedia.org/wiki/Milankovitch_cycles
    The CO2 that had been added to the atmosphere then caused warming of its own, which greatly amplified the warming that had already taken place; and as a result the overall amount of warming was much higher and lasted far longer than would have been the case without the influence of CO2. Without the greenhouse effect, the warming would have lasted for a far shorter time and been far less.
    http://www.realclimate.org/index.php?p=13

    Why do some of you dismiss the lag between T and CO2 as irrelevant?

    It is irrelevant to what is going on now, which is that we have now artificially increased CO2 levels by more than 30% in only 150 years, with even more rapid rises likely during this century. This is something that has never happened before in the earth’s history. And it is also irrelevant in the sense that no climatologist has ever claimed that the ice core data is important evidence for global warming theory. Durkin was using a straw man argument:
    http://en.wikipedia.org/wiki/Straw_man
    … by pretending that the ice core data was important to global warming theory, when it is not.

    Where are the analyses of the ice-core data that Durkin used?

    Why are they wrong?

    They are not wrong about what the ice core data *is* but they are completely wrong about what it *implies* – see explanations above. And please *read* the articles I linked to before replying.

    Durkin and co. are perfectly well aware of all the above, it isn’t at all controversial in scientific circles, which is what annoys so many of us here. It is highly unethical to knowingly use fallacious arguments on a scientific subject, and especially on a subject as important as this one is, that they know perfectly well are fallacious, in order to mislead people. I can’t say any more about that aspect of it here because this is a scientific forum and it is not an appropriate place to discuss what might be motivating these people.

  331. Dave Rado:

    Re. #326 you’re misundersatanding what Carl wrote. He does not mean “to what extent do natural cycles influence climate”, which seems to be what you think he meant. The natural influences are fully taken into account in all the climate models, see:
    http://www.grida.no/climate/ipcc_tar/wg1/figspm-4.htm

    He means “to what extent does the climate simply change for no reason whatsoever, in the process disobeying all the laws of physics”; and the answer to that question is that it doesn’t.

  332. Leo:

    OK, so I’ve just looked again at Caillon et al

    http://icebubbles.ucsd.edu/Publications/CaillonTermIII.pdf

    (which is Durkin’s source for the lag data – sorry for not clocking that above)

    and I see that

    “The radiative forcing due to CO2 may serve
    as an amplifier of initial orbital forcing, which is
    then further amplified by fast atmospheric feedbacks
    (39) that are also at work for the presentday
    and future climate.”

    (Which, if I understand it correctly means an initial temperature rise may cause a realease of CO2 after a lag of 800 years, which may lead to further warming)

    But has anyone actually shown this to be the case?

  333. Barton Paul Levenson:

    [[Left field: Methans quote: http://en.wikipedia.org/wiki/Methane “Methane in the Earth’s atmosphere is an important greenhouse gas with a global warming potential of 23 over a 100 year period. This means that a 1 tonne methane emission will have 23 times the impact on temperature of a 1 tonne carbon dioxide emission during the following 100 years”
    The focus should be to reduce methane and worry less about c02, but that would not be politically correct? ]]

    Your assignment for tomorrow: Look up a table of the constituents of Earth’s atmosphere. Find the mean molecular weight of air and the molecular weights of carbon dioxide and methane. Find the mass fraction of each and the total airborne mass of each. Compare and contrast.

    Here’s a hint to get you started: The total mass of Earth’s atmosphere is about 5.136 x 10^18 kilograms.

  334. Dave Rado:

    Re. #322, as people have pointed out over and over again in this thread, there are many influences on climate; and many more influences on weather; than CO2 alone. Year on year changes are *weather*, *not* climate. E.g. La Nina/El Nino. *Please* read up about them before posting back.
    http://en.wikipedia.org/wiki/Climate
    http://en.wikipedia.org/wiki/Weather
    http://en.wikipedia.org/wiki/ENSO
    http://www.grida.no/climate/ipcc_tar/wg1/figspm-4.htm

  335. Barton Paul Levenson:

    [[One more question when reviewing global temperatures, on a year to year basis, temperatures do not increase some years they actual decrease: This I find interesting as c02 only ever increases: ]]

    CO2 is not the only thing that affects climate or Earth’s temperature. It is also affected by other greenhouse gases, changes in solar luminosity, cloud cover, aerosols, and orbital changes. Nobody said it was a one to one relationship. What they did say is that, other things being equal, more CO2 yields a hotter ground.

  336. Barton Paul Levenson:

    [[What hard data shows that CO2 increases T rather than the other way round?]]

    John Tyndall demonstrated in 1859 that CO2 absorbs infrared light.

    All objects, unless they are at absolute zero temperature, radiate photons in an amount proportionate to the fourth power of their temperature.

    Sunlight heats the ground. The ground radiates infrared. Carbon dioxide (and water vapor, etc.) absorb the infrared. The greenhouse gases heat up. They radiate infrared themselves. Some of the infrared goes back to the ground.

    The ground is getting both sunshine and “atmosphere shine.” Increasing CO2 increases the IR coming from the atmosphere, and heats the ground more than it was heated before.

  337. Barton Paul Levenson:

    [[Why do some of you dismiss the lag between T and CO2 as irrelevant?]]

    Because it describes natural climate variations, and we know the present surge in CO2 is not natural.

  338. Leo:

    Thanks Dave (330)

    as you’ll have gathered I posted 332 before your response came up.

    I’ll go away and digest what you’ve written.

  339. Leo:

    336
    thanks for the theory but I was hoping for observation of this in action on an appropriate scale over time

  340. Angus:

    From the last few posts I take it that my summary in 325 is correct and I can expain to the locals in my pub why the documentary thay have all been talking about was rubbish. Thank you gentlemen, for helping me to understand this particular point. To win this argument, you do need to win the man in the pub

  341. Dave Rado:

    Re. #32 and taking into accoutn #338; in addition to what I posted in #330:

    (Which, if I understand it correctly means an initial temperature rise may cause a realease of CO2 after a lag of 800 years, which may lead to further warming)

    But has anyone actually shown this to be the case?

    1) Given that the greenhouse effect is as well established physics as Newton’s laws are, if it were not the case, then you would have to somehow explain why the greenhouse effect mysteriously failed to operate during those thousands of years. No-one has ever tried to explain that, and Durkin simply ignored it.

    2) The amount of warming that took place and the lenghth of the warming that took place is impossible to explain unless you take the greenhouse effect into account.

    3) If the warming had been caused by orbital fluctuations and ice melting alone, the tropics would have warmed far less quickly relative to the Arctic than they did.

  342. Andy Mitchell:

    Carl Wunsch should make his complaints to the ITC. Martin Durkin has previously made ‘Against Nature’ which was found by the ITC to have ‘distorted or misrepresented’ contributions. Channel 4 was forced to make an apology in primetime.

    http://www.ofcom.org.uk/static/archive/itc/itc_publications/complaints_reports/programme_complaints/show_complaint.asp-prog_complaint_id=40.html

  343. tamino:

    Re: Angus and Leo

    Come on, everybody! Angus and Leo have expressed skepticism (not denial) based on the propaganda they’ve been fed, and that’s entirely natural. But instead of just accepting it at face value, they’ve come to RealClimate (which so many of us tout as the best climate-science blog on the net) to get answers. They’ve asked questions, and the answers don’t satisfy, so they ask more questions. Frankly I admire their willingness to look deeper than the surface.

    So instead of just retorting with a snarky, “Do your homework first,” we should be giving them the best answers of which we’re capable. After all, these are exactly the people we’re trying to persuade: the man (or woman) in the pub. And, as much as we may consider ourselves to be graced with more thorough knowledge, it’s the man & woman in the pub who will go to the voting booth and choose the leaders who have the power to do something about it.

    If our answers have failed to persuade them, the fault, good Horatio, lies not in our stars, but in ourselves.

    To Angus and Leo: I’ll try to answer your questions as best I’m able. But right now I have to go to the airport for a long trip, so I’m not sure when I’ll be able to get to it. But if you’ll be patient, without losing your interest or your skepticism, then if nobody else answers adequately, I’ll be back. Soon.

  344. Angus:

    Thanks again tamino, have a safe trip. I for one am now convinced. CO2 is a greenhouse gas that is released when the earth warmed, there was complex feedback mechanism that caused the temperature to oscillate back down to “normal” levels when external energy was removed. The mass of C02 released would effect the length and periodicty of this feedback. The rate at which we have pumped CO2 into the atmosphere over the last century means that this model no longer applies.
    This probably over simplistic, but before I get flamed again, please consider tamino’s comments, suffer us fools with good humour rather than contempt.

  345. Hank Roberts:

    Well said, Tamino.
    It is true that new people ask FAQs here over and over; while there are many pointers and the search tool, the actual FAQs do take some basic reading, the sidebar links are helpful in that.

    It ain’t rocket science — it’s harder.

  346. P. Lewis:

    Re #328 (Leo)

    If CO2 is causing most of the global warming, we need to be told how that has been shown in clear, unambiguous terms.

    CO2 is not doing most of the global warming. That is the prerogative of Sol and H2O. Pumping fossil-carbon CO2 into the atmosphere is a prime factor in anthropogenically enhanced global warming (AGW). There are “two processes”: natural and AGW.

    What hard data shows that CO2 increases T rather than the other way round?

    There are misconceptions here.

    Temperature increases enable the release of locked-in CO2 (e.g. from ocean degassing). CO2 can follow temperature up (e.g. out of an ice age) and down (e.g. in to an ice age).

    But the classical and quantum physics of IR absorption (and experimental work) show that CO2 traps heat (causing the temperature to rise); more CO2, more heat trapped; temperature goes up. Temperature can follow CO2.

    The effects work independently and in concert. It’s a feedback/forcing. It doesn’t matter which comes first, the chicken or the egg. It is that simple (except that it is not that simple, because you have various other positive factors; and you have negative feedbacks trying to counter the rise in temperature, e.g. aerosols). So far as I’m aware, there hasn’t been a peer-reviewed publication discounting this basic physics of CO2 absorption of IR (since the QM work was done with regard to band shapes in the mid to late 50s(?)). It’s literally textbook stuff (I’m sure someone can recommend one if you ask.).

    Why do some of you dismiss the lag between T and CO2 as irrelevant?

    The lag is not strictly irrelevant (physically); if the CO2 wasn’t released in time and in sufficient quantities before the Earth’s various wobbles and/or solar output start to decline again, then it wouldn’t be irrelevant. And if you’re discussing palaeoclimate then it is relevant to what’s going on. The lag is irrelevant in the context of AGW (for the reasons already indicated).

  347. Angus:

    Dear Mr Whitney
    I was initially impressed by this documentary and resolved to find the truth for myself. I have spent about a week here and read a lot of science, not pseudo science. It’s heavy going but I would suggest you do the same, if you have a open mind you may be be surprised.

  348. Bob:

    Seems to me that if we can causing warming with CO2 and cooling with sulphates, we should be able to set just about any temperature we want.

  349. Michael:

    Bob (348)

    Our technology does allow us to alter the landscape to our choosing, but if nothing else, the science and research put into understanding the ecosystem has, if nothing else, taught us that the Earth is a fairly wise system and knows what is best for it.

    Man’s biggest goal (at this point) is learning how to live with nature without unintentionally altering it. If nuclear winters, aerosols, methane or CO2 could give us the temperature we wanted, the more important concern would be ‘what do we screw up this time?’

    If you consider man to be nothing but an animal, then the Earth deals with us as so. The Law of Conservation of Mass basically states: In a closed systerm, matter cannot be created or destroyed, only changed (except in a nuclear reaction). The minute we became capable of altering the ‘whole’, we endangered ourselves. The earth is an extremely complex system (surprising, I know). Every change we make, be it fertilizer in the soil, a 70 story building in Manhattan, or tearing down a tree, there are repercussions.

    While science has helped man gauge the effect of our ripples on the pond, we’re still working on how to keep the pond’s surface still.

  350. Joe Rosenfels:

    If you accept that adding Green house gases to the athmosphere will have a temperature increase (forget the specifics about c02 and ice cores, time delay, glaciers growing, antartic getting thicker etc) see this article.

    http://www.bbc.co.uk/science/horizon/2003/bigchilltrans.shtml

  351. BarbieDoll Moment:

    “Seems to me that if we can causing warming with CO2 and cooling with sulphates, we should be able to set just about any temperature we want. “

    Those are two different issues. CO2 decreases the window space available
    in the atmosphere for reradiated energy to escape off into space.

    Sulfates, like aersols, cause light scattering, an albedo effect.

    Cumberland Sulfur Emissions
    http://www.tva.gov/environment/air/ontheair/cumberland.htm

    …”Small particles are formed in plumes from coal-fired power plants when SO2 is oxidized to sulfate (SO4-2) aerosol particles. In the eastern United States in particular, these sulfate particles contribute significantly to the concentration of very fine particle matter (PM2.5), that causes reductions in visibility because of its light-scattering properties (Table 1). On the very haziest days, sulfate aerosols may contribute more than 80 percent of the visibility reduction in the Tennessee Valley region.”…

    GOES-8 Sounder Profile Retrieval Information
    Radiative Transfer Equation Basic Principles
    http://cimss.ssec.wisc.edu/goes/sounder_tutorial/profinfo.html
    …”The weighting function, the derivative of transmittance with respect to height (pressure), specifies the relative contribution each atmospheric layer makes to the radiation emitted to space and thereby determines those regions of the atmosphere which are sensed from space at this wavelength.”..

    …” Around the broader CO2 and H20 absorption bands, vertical profiles of atmospheric parameters can be derived. Sampling the center of the absorption band yields radiation from the upper levels of the atmosphere (e.g., radiation from below has already been absorbed by the atmospheric gas). Sampling away from the center of the absorption band yields radiation from successively lower levels of the atmosphere. In the wings of the absorption band are the windows that view to the bottom of the atmosphere. Thus, as a spectral band is moved toward the center of the absorption band, the radiation brightness temperature decreases due to the decrease of temperature with altitude in the lower atmosphere. “…

    …”Because the concentration of CO2 is nearly uniform in the atmosphere, the weighting functions specific to the CO2 absorbing bands show little variation with location. However, water vapor concentrations vary greatly from one location to another. The non-uniform concentration of water vapor in the atmosphere will cause the weighting functions specific to the H2O absorbing bands to vary by location. “…

  352. George:

    A reference to a paper by Notholt et al “Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity” from GEOPHYSICAL RESEARCH LETTERS is making the rounds in some of the debates on global warming.

    It’s being used to counter the argument that SO2 aerosols caused the relatively cool period from 1940 to 1960. And to show that the Global Warming Mafia can’t even get their SO2 effects right.

    To me it seems to actually be saying that in addition to what everyone says about SO2 causing cooling it also increases the transport of water vapour into the stratosphere, augmenting water vapour’s warming effect.

    Does anyone have knowledge of this paper and it’s relevance to global warming? Does it have any impact on the models in use?

    Thanks

  353. Hank Roberts:

    Uh, four year old newspaper article about a story that’s been debunked here — and your point is?

  354. Jeff:

    lolz at GW nutters. I wonder how many of you were this critical about Al Gores inconsistancys. Let the debate begin but let it begin in an open and honest manner. The point of the movie is debunk claims by Al Gore and the GW-ists. It does a great job at exposeing some bad claims that should have been delt with by Gore.

  355. guthrie:

    Bob- only if we have vast amounts of energy and material to spare. How do you propose to create the vast cloud of sulphates, let alone increase or decrease the amount of CO2 in the atmosphere by millions of tons every year?

    Joe, thats an old, sensationalist article, covering the North atlantic. Even if it were to happen, (and climatologists currently think the catastrophic scenario is very unlikely.) it would only really affect Norther Europe. The rest of the world would still be warmer.

  356. angus:

    Please forgive my ignorance again, is there a model which matches the T/CO2 ice core record and what happens to it if todays CO2 level is suddenly injected at the end of the last ice age?

  357. Leo:

    So. Tell me if I�ve got this right. The man-in-the-pub, one-stop-shop, bullet-point explanation is this:

    – CO2 is one of a number of “greenhouse” gases, which are known to act, with the stimulus of energy from sunlight, to make the planet warmer than it would be through the action of sunlight alone
    http://en.wikipedia.org/wiki/Greenhouse_effect

    – Ice core data shows the concentration of CO2 in the atmosphere rising and falling naturally over time (perhaps due largely to warming and cooling of the oceans amongst other factors, but who cares?).
    http://icebubbles.ucsd.edu/Publications/CaillonTermIII.pdf

    – Ice core data also shows that CO2 concentration is currently on an upward trend, and is at its highest level for about 330,000 years
    http://en.wikipedia.org/wiki/Image:Vostok-ice-core-petit.png

    – Very recently it has increased more dramatically than would be consistent with this natural variation
    http://commons.wikimedia.org/wiki/Image:Carbon_Dioxide_400kyr.png

    – This jump not only coincides with industrialisation and the known increase in combustion of fossil fuels
    http://commons.wikimedia.org/wiki/Image:Global_Carbon_Emission_by_Type.png
    http://cdiac.ornl.gov/trends/emis/em_cont.htm

    but it has been demonstrated that fossil fuels are to blame by measuring decayed radioactive carbon isotopes in the atmosphere. (?)
    ( Reference?)

    – Theoretically, it would be anticipated that the Greenhouse Effect would cause this high combined level of CO2 to have a marked effect on global temperature.

    – At the same time it has been observed that global temperatures, whilst apparently at a peak or plateau in the long term
    http://en.wikipedia.org/wiki/Image:Vostok-ice-core-petit.png

    are in fact increasing dramatically in the short term
    http://www.globalwarmingart.com/wiki/Image:Instrumental_Temperature_Record_png

    – Models incorporating all known effects on global temperature suggest that the current temperature increase is indeed linked to increased greenhouse gases.
    http://www.globalwarmingart.com/wiki/Image:Climate_Change_Attribution_png

    How am I doing?

    So Durkin is wrong to attack Gore’s suggestion that the Vostok core T and CO2 records show a cause-and-effect relationship because that’s not the point. The point is that our output of CO2 when coupled with an already high background level is reaching unprecedented concentrations. Which, from all that we know, would suggest a greatly increased greenhouse warming. The likely effects of which are a whole different can of worms.

    He is also wrong to try and overshadow the importance of CO2 with discredited theories about cloud formation, not least because even if it were true it would be beyond our control, whilst CO2 emissions, however small their effect, are definitely within it.

    BUT
    Scientifically
    Is he wrong to urge caution when relying on a model for that crucial last link?
    Is he really wrong to throw the debate so harshly into the public domain, however crassly?
    It would be dreadful to become complacent we have the answer only to discover global warming is being caused by another factor we have failed to mitigate.

    Politically
    Is he wrong to urge caution in making sweeping global policies that could make life impossible for the world’s most vulnerable people?

    Flippantly
    Why can’t mud huts have chimneys anyhow?

  358. angus:

    Leo, I think both Durkin and Dole were both guilty of “tabloid science”, aiming to sway the masses. Also, in an unprecented situation, a model is all we have to go on when predicting the future. I think if this went to a court of law, a jury would find the AGW case proved beyond reasonable doubt. Hey, there’s a thought lets get the lawyers involved!

  359. Matthew Lemin:

    Hopefully a simple question from a layman!
    To what extent is the change in Total Solar Irradiation (TSI) taken into account in the models used for the IPCC report?

    Follow on questions:
    Do the models assume a static constant for solar forcing?
    Or do they assume a change in line with projections of future sunsport, TSI and magnetic field flux in the sun?

    I have in mind Willson’s suggestion that TSI has changed by 0.05% a decade since 1978 and that other data points to this having been the continuation of a trend over the last 100 years.
    http://www.giss.nasa.gov/research/news/20030320/

    Also considering the Carbon 14 data which suggests that solar activity is currently at a 1,000 year high.
    http://en.wikipedia.org/wiki/Image:Sunspot_Numbers.png
    (graph on right hand panel)

    If the models fail to take into account that we may have been in a long-run period of continued increases in solar activity, and that the activity may affect global temperatures, is there not a danger that we are over-estimating the influence of greenhouse gas emissions simply because we have under-estimated the effect of solar forcing?

    [Response: The most recent assessments of the satellite data show no trend since 1979 (http://www.pmodwrc.ch/pmod.php?topic=tsi/composite/SolarConstant ). 14C can’t be used over the last 150 years due to contamination by fossil fuel use (which reduces the 14C content of the atmosphere significantly) and the bomb tests in the 1950’s (which increased it). Cosmic Ray trends over the last 50 years are non-existent. There are 11 year cycles that are clear though. Models use the best estimates of how TSI has changes (including the different changes in different parts of the spectrum), but when you stack it up against greenhouse gases, the trends would have to be about 10 times as large to even be comparable. – gavin]

  360. Hank Roberts:

    > Politically
    > Is he wrong to urge caution in making sweeping global policies that could
    > make life impossible for the world’s most vulnerable people?

    Certainly not, and that’s why Gore has been urging caution for a long time now.

    It’s what we did, mostly out of ignorance, by using fossil fuel so fast for fifty years. I”m not talking about ‘global warming’ — I’m talking about changing the oceans so the plankton, base of the food chain and primary photosynthesizers, are damaged.

    It’s like smoking knowing you’re putting the people around you at risk from combustion byproducts — immoral, and stupid.

  361. angus:

    excuse my typo, Dole for Gore, I would doubt they are interchangeable on this issue. I was somewhat distracted as my daughter just told me she was going to have a baby, suddenly I am even more convinced that we can’t sit by and see what happens.

  362. Barton Paul Levenson:

    [[Seems to me that if we can causing warming with CO2 and cooling with sulphates, we should be able to set just about any temperature we want. ]]

    Technically that’s true. But both have other consequences which are not so good. Sulfates hurt human health and carbon dioxide acidifies the oceans. In the long run it’s best to stop putting both into the atmosphere.

  363. Barton Paul Levenson:

    [[the Global Warming Mafia can’t even get their SO2 effects right.]]

    Youse keeps talkin’ like dat, and we’re gonna have to take youse for a global warmin’ ride.

    One paper doth not a consensus make. If he (or she, or they) has/have good results, then they will be accepted if others can reproduce them. Otherwise, they won’t be.

  364. Barton Paul Levenson:

    Angus, congratulations to you and your daughter.

  365. David B. Benson:

    Re #356: angus — Yes. The Archer/Ganopolski paper has been commented upon at least twice in different, recent threads. Roughly, if humans can limit cardon exhaust into the atmosphere to a mere 1000 Gt (300 Gt so far) then the climate will finally return to normal in about 100,000–150,000 years.

    Re #357: leo — You asked how you were doing so far. Looks to me that you have the jist of the science, but I’m only a fairly recent amateur at climatology…

  366. Alvia Gaskill:

    Harken Apostates, Lindzen Issues a Stern Rebuke

    http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=440869&in_page_id=1811&in_a_source=&ito=1490

  367. Hank Roberts:

    I can’t believe the Daily Mail quoted Dr Lindzen correctly, and asked them to recheck.

    They attribute this to Dr. Lindzen:

    > “a very gently warming trend, …. this minor trend could have easily have been
    > caused by irregularities such as volcanic eruptions …”

    I know volcanos are warm — but the notion they’re warming the Earth seems contrary to observations.

  368. moira:

    What the BBC think of TGGWS. The Now Show, 16/3/07 BBC Radio 4

    http://www.bbc.co.uk/radio4/comedy/nowshow.shtml

  369. J.C.H:

    From Lindzen’s rebuke:

    “… Stern also refers to ‘significant melting of and an acceleration of ice floes’ near the coast of Greenland because of global warming.

    Yet several reputable scientific studies have shown that the mass of the Greenland ice sheet is actually expanding, while Stern also fails to note that the temperature of Greenland is now lower than it was in 1940 and little changed from the first measurements in the 1780s. …”

    I’m far from being an MIT physicist, but one could easily have both expansion of the icecap and expansion of the ice melt; as in, it snows on top a whole bunch and it melts on the edges a whole bunch.

    If it’s warming, could it also be snowing a lot more in certain places? Maybe it’s snowing more on top of the Greenland icecap, which is a bit higher than the coastlines of Greenland, which, therefore, could be a bit warmer because they’re down lower – kind of like an island with snow-capped peaks and bikinis on the peaks on the beaches. In splendor, such peaks can coexist – I think?

  370. Mickey:

    There seems to be more “faith” in Global Warming than science. It is interesting that GW advocates totally discount a total picture of many related theories and focus on only the CO2 issue. By simplifying the data and cherry picking you end up complicating the issue. The other major flaw in the GW frenzy is your reluctance for peer review. If you don’t respect the professional input of other scientists then there is legitimate reason to assume you also have no confidence in your theories.
    You certainly don’t have exclusive knowledge here.

  371. Hank Roberts:

    Bingo.

  372. Bob:

    Now I am just wondering, if sulphate pollution from the 1940’s to the 1970’s caused global cooling during that period, but was fixed with Clean Air acts of the 1970’s, why isn’t pollution from China, India, Mexico, Russia, and other parts of the world, which have no clean air acts, doing the same ?

  373. Dick Veldkamp:

    Re: #370 (Mickey)

    Just out of curiosity, WHY in the world do you believe that:
    – there’s more faith than science in GW?
    – scientists discount other theories just like that without examining them?
    – they are cherry picking data?
    – they are afraid of peer review?
    – they have no confidence in their own theory?

    Before you make claims such as these, you’d better take a couple of hours to read up on the evidence. Use this site. If you think that’s too technical, check out Wikipedia. Or
    go here for excellent answers: http://gristmill.grist.org/skeptics

  374. Bladernr1001:

    Hmmmmmmm,

    Judging from this comment board I would have to conclude that the debate over global warming is not over.

    Any time I see people like polititians and scientists on the public dole saying anything….I look at it with a jaundiced eye.

  375. Hank Roberts:

    >372 Bob
    Because in the 1940-1970 period, the total fossil fuels so far burned was less than half today’s total; the CO2 increase had started at the time, but look at the pattern:

    http://www.globalwarmingart.com/wiki/Image:Global_Carbon_Emission_by_Type_png

    Aerosols work fast and go away fairly fast; after the Clean Air Act reduced those in the 1970s, they fell out of the atmosphere.

    But the CO2 put into the atmosphere during the same time span persists — it stays up much longer.

    Once a given amount of CO2 increase (above what nature can remove at the same pace) happens, we get the period of increasing temperature until the planet reaches equilibrium.

    http://www.globalwarmingart.com/images/a/aa/Global_Warming_Predictions.png

    During 1940-1970, when fossil fuel began being burned in large amounts, the aerosols acted right away — reflecting some solar energy; the CO2 was only starting to increase.

    The heating from thatt’s happening now — the heating committed to by the fossil fuel use up to 1970 goes on for decades; the effect we experience is — probably — slowed down by the second round of aerosols, acting now, but it’s acting on a very different background.

    In the time up to the 1940s, we hadn’t much overwhelmed the planet’s annual ability to recycle CO2.

    That’s an amateur reader’s explanation; stand by for someone with real science credentials to, I hope, correct and improve my understanding. I post what I think, expecting to learn better thanks to the scientists.

  376. BarbieDoll Moment:

    RE: “Notholt et al “Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity”

    No offense meant at all, but I am not sure if I even understand any of the reasoning you cite or mention because it seems to fails the basic science understandings to date.

    The link for the paper for which you spoke.

    Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity
    J Notholt et al
    Geophysical Research Letters 32 (7), 07810 (09 Apr 2005)
    http://dx.doi.org/10.1029/2004gl022159
    …”Here we present a mechanism that would link increasing anthropogenic SO2 emissions in southern and eastern Asia with an increase in stratospheric water.”…”Our model calculations suggest that such a mechanism could increase the amount of water that entered the stratosphere in the condensed phase by up to 0.5 ppmv from 1950â??2000.”

    Other papers that discuss the modeling and or science of the matter.

    Volcanic Hazards: Gases (sulfur dioxide, carbon dioxide, hyrdogen chloride, and hydrogen fluoride) U.S. Department of the Interior, U.S. Geological Survey 10 January 2006
    http://volcanoes.usgs.gov/Hazards/What/VolGas/volgas.html
    “The most abundant gas typically released into the atmosphere from volcanic systems is water vapor (H20), followed by carbon dioxide (C02) and sulfur dioxide (S02).”…

    Global Cooling After the Eruption of Mount Pinatubo: A Test of Climate Feedback by Water Vapor
    Science, Volume 296, Issue 5568, pp. 727-730 (2002) Soden, Brian J.; Wetherald, Richard T.; Stenchikov, Georgiy L.; Robock, Alan
    http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2002Sci…296..727S&db_key=PHY&data_type=HTML&format=&high=42d4f8714c06778
    …”Here, we first highlight the success of the model in reproducing the observed drying after the volcanic eruption. Then, by comparing model simulations with and without water vapor feedback, we demonstrate the importance of the atmospheric drying in amplifying the temperature change and show that, without the strong positive feedback from water vapor, the model is unable to reproduce the observed cooling. “…

    Two-decadal aerosol trends as a likely explanation of the global dimming/brightening transition
    Geophysical Research Letters 33 (15), 15806 (2006)
    http://dx.doi.org/10.1029/2006gl026471
    …”We show that the inter-annual trend in solar radiation between 1980 and 2000 mirrors the trend in primary emissions of SO2 and black carbon, which together contribute about one-third of global average aerosol optical depth. “…

    Climate simulations for 1880-2003 with GISS modelE
    J Hansen et al.
    ArXiv Physics e-prints, (Oct 2006)
    http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2006physics..10109H

    …”Satellite observations of the planetary radiation budget perturbation following the 1991 Mount Pinatubo eruption [Wong et al., 2004] provide a strong constraint on the aerosol forcing for that volcano [Figure 11 in Efficacy, 2005]. That comparison suggests that the above relationship between aerosol optical thickness and climate forcing is accurate within about 20%.The stratospheric aerosol forcing becomes more uncertain toward earlier times. We estimate the uncertainty as increasing from ±20% for Pinatubo to ±50% for Krakatau.At intervals be tween large eruptions prior to the satellite era, when small eruptions could have escaped detection, there was a minimum uncertainty ~0.5 W/m2 in the aerosol forcing. Stratospheric aerosol optical thickness was zero in our climate model control run. Our future control runs will include stratospheric aerosols with Ï? (λ = 0.55μm) = 0.0125, the mean visible optical thickness for 1850-2000, with the rationale that this is a better estimate of the long-term mean stratospheric aerosol optical depth than is the use of zero aerosols. We recommend (Appendix A) that other researchers include such a mean aerosol amount in control runs used as spin-ups for transient simulations, because the deep ocean then approaches a more appropriate equilibrium temperature. Omission of this forcing from the control run alters the rate of ocean heat storage in transient climate simulations. Use of the mean aerosol optical depth in the control run also would have reduced the modeled Krakatau cooling by almost 10%, for an appropriate reason, bringing model and observations into better agreement (see section 4.2).”…”The uncertainty in the net forcing is dominated by the uncertainty in the aerosol forcing, which we suggested above to be at least 50%. Even with the most optimistic assessment of our understanding of the forcings, we must conclude that the net forcing is uncertain by ~ 1 W/m2. Accepting these forcing estimates at face value implies that the net forcing is uncertain by about a factor of three, primarily because of the absence of accurate measurements of the aerosol direct and indirect forcings”….”Overall, we conclude that there is good qualitative and semi-quantitative agreement between simulated radiation-related quantities and observations, e.g., with the phenomenon of â??global dimmingâ?? [Stanhill and Cohen, 2001; Liepert, 2002; Cohen et al., 2004], the reduction of solar radiation incident on the surface. Our model results indicate that dimming is due primarily to absorbing aerosols and secondarily to the aerosol indirect effect on clouds. The same forcings are principal causes of a decrease in the amplitude of the diurnal cycle of surface air temperature, such a decrease being in accord with observational evidence [Karl et al., 1993]. The model yields a significant increase of global mean cloud cover, largely due to the aerosol indirect effect, but the local effect does not generally exceed local unforced variability in the model.”…

    Volcanoes and climate: Krakatoa’s signature persists in the ocean.
    P J Gleckler et al.
    Nature. 439 (7077), 675 (09 Feb 2006)
    http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16467829&query_hl=7&itool=pubmed_DocSum
    …”Volcanically induced cooling of the ocean surface penetrated into deeper layers, where it persisted for decades after the event. “….

    Significant decadal-scale impact of volcanic eruptions on sea level and ocean heat content.
    John A Church, Neil J White, and Julie M Arblaster
    Nature. 438 (7064), 74-7 (03 Nov 2005)
    http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16267551&query_hl=14&itool=pubmed_DocSum
    …”Here we use observations of ocean heat content and a set of climate simulations to show that large volcanic eruptions result in rapid reductions in ocean heat content and global mean sea level. “…

    Ocean Heat Content Variability in the Second Half of the 20th Century: Results from the IPCC AR4 Simulations.
    K Achutarao et al.
    AGU Fall Meeting Abstracts, 4 (Dec 2006)
    http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2006AGUFMOS42A..04A&%3Bdb_key=PHY
    …”We specifically examine the role of varying observational coverage and the inclusion of volcanoes in the simulated variability of ocean temperatures. ”

    2006 Was Earth’s Fifth Warmest Year
    NASA GISS: Research News, (08 Feb 2007)
    http://www.giss.nasa.gov/research/news/20070208/
    …”Blue semi-circles mark La Niñas, red rectangles mark El Niños, and green triangles mark large volcanoes.”…

    Solar influence on climate during the past millennium: Results from transient simulations with the NCAR Climate System Model
    Caspar Ammann et al.
    Proceedings of the National Academy of Sciences 104 (10), 3713 (06 Mar 2007)
    http://dx.doi.org/10.1073/pnas.0605064103
    …”High scaling of the solar irradiance leads to model temperatures by the end of the century that are only marginally (0.1°C) warmer than those from the low and medium scaled forcing. This finding suggests that, while solar irradiance changes and explosive volcanism were the dominant forcings in preindustrial times, their combined role has been changing over the past century. Although these natural forcing factors could be responsible for some modification of the decadal structure over the 20th century, they only played a minor role in the most recent warming.”…

    Southern Ocean warming due to human influence
    Geophysical Research Letters 33 (19), L19701 (2006)
    http://dx.doi.org/10.1029/2006gl027247
    …”I also show that climate models that do not include volcanic aerosols produce mid-depth Southern Ocean warming that is nearly double that produced by climate models that do include volcanic aerosols. This implies that the full effect of human-induced warming of the Southern Ocean may yet to be realized. ”

    Here are additional papers

    Private Library Seasonality of Volcanoes/Climate/Water
    34 abstracts
    http://adsabs.harvard.edu/cgi-bin/nph-abs_connect?library&libname=Seasonality%20of%20Volcanoes/Climate/Water

    Some of my other libraries with extensive scientific papers on the subject(s) matter

    volcanoes and climate
    http://www.connotea.org/user/msredsonyas?q=volcanoes+%2B+climate

    Volcanic Activity
    http://www.connotea.org/user/msredsonyas/tag/Volcanic%20Activity

    Climate Sciences
    http://www.connotea.org/user/msredsonyas/tag/Volcanic%20Activity

    Intergovernmental Panel on Climate Change (IPCC)
    http://www.connotea.org/user/msredsonyas/tag/Intergovernmental%20Panel%20on%20Climate%20Change%20(IPCC)

    Aerosols
    http://www.connotea.org/user/msredsonyas/tag/aerosols

  377. Angus:

    I have read the Archer Ganopolski paper. They say in para 16 that they the amplyfing role of natural CO2 in deglaciations is poorly understood, does this mean that the models used do not simulate oscillations in temp and CO2 levels as they come down from the maximum? Again a dumb question, but isn’t the key to understanding the anthoprogengic addition of CO2, is to model and understand the natural process it disrupts?

    http://geosci.uchicago.edu/~archer/reprints/archer.2005.trigger.pdf

  378. Manboy:

    Re #370,

    I’m not sure you know what you’re on about. “Reluctance” for peer review ?

    Such as IPCC ?

    Such as scientific research done on the matter and published in peer-reviewed journals ?

    Such as the Arctic Climate Impact Assessment ?

    I’d state the opposite : It is infact the DENIALISTS who rely so much on “faith”. The studies on climate change are based on science. You don’t like it but that’s the way it is.

    You’re just taking the mickey (pun intended) out of folks who have an serious interest in CC, aren’t you ?

  379. Geoff Wexler:

    IPACACC (UN’s International Panel against Cheating about Climate Change)

    Initial agenda:
    1. The identification of spin, cheating etc.
    1. Identification and definition of the forcing agents e.g the American Petrol Inst. ,Exxon-Mobil, etc.
    2. The distinction between forcing agent and causation (for cheating).
    3. An attempt to solve The lead-lag problem i.e which occurs first the funding or the dodgy papers?
    4. The detection and attribution problems e.g. the detection of input from Exxon and estimate of its significance.

    Seriously, the CO2 emitters have every right to highlight skeptical views but they if they do so covertly they should not complain when it is exposed. The C4 programme sneered at those who refer to Exxon funding while at the same time concealing that one of the graphs was funded by them (the one by Soon which I mentioned above). That graph shows a net coolng between 1940 and 2000 for the Antarctic. Of course the Exxon connection is strictly irrelevant except that it was implicitly denied by C4. I am still awaiting comment from the experts as to its status.

  380. David B. Benson:

    Re #377: Angus — Archer & Ganolpolski used a fairly simple, but robust, model of global climate due to Paillard in which only temperature and ice volume occur. They treat carbon dioxide entirely as a forcing, except for the deep ocean contribution. This latter is just a matter of adjusting the parameters in the Paillard model.

    One possible source/sink of up to 60 ppm of carbon dioxide during the transition through an interglacial from one stade to the next is coral reefs. Archer & Ganolpolski state, again in paragraph [16], that including such effects would prolong the long-term climate impact.

    I believe the results are good enough to suggest long-term impacts. However, I do not view the work as precise enough to state, for eample, that the maximum global temperature increase from adding 1000 Gt of caron will be, say, 3 K. For that a more sophisticated approach to modeling carbon dioxide would be required.

  381. Eric:

    Well it’s been a funny kind of month. Every day I wake up to the Radio 4 news. I listen and – yes – there it is. Someone has mentioned the word(s) ‘environment’ or ‘green’ or ‘carbon footprint’ or ‘global warming’. I fear that I shall scream if I hear them again. Some politician tells us how additional taxes will help sort the problem and a friendly Greenpeace representative tells us we are all doomed. The message is always the same. Why is it always presented as a dead certainty? Where is the balanced scientific discussion?

    Then ….10 days ago – a wonderfully refreshing program on Channel 4. Biased? Who cares. It has the desired effect. Suddenly everyone wants to talk about the Science.

    At this point, as a caring and concerned and member of the human race, with no inside knowledge on these matters, I felt I ought to do something about my lack of expertise in this area. I set myself the task of the reading the newspapers and surfing the internet.

    The experts don’t seem to agree with each other. The only way I am going to be able to work this one out is to get hold of the original data and sort it out myself. I spend hours surfing but it is so difficult to locate the data sets. Time for bed.

    It is now Saturday morning. There is a discussion on the radio. The nice Greenpeace man calls the C4 program “Junk Science” not like the really informative articles in the “Independent” newspaper. So it’s back to the Independent for some independent advice. I get out my crumpled copy dated 14th March. I am immediately struck by the 2 central graphs concerning Temperature and Solar Activity. How could C4 have got it so wrong? The 2 graphs look nothing like each other! Lets have a look at the Peter Laut paper (Journal of Atmspheric and Solar-Terrestrial Physics 65 – 2003) – Yep, those last 2 points are wrong, the solar cycle lengths should be 10.61 and 10.59. Back to the Damon and Laut article (2004) to see the effect on the graph. Let’s compare the original graph with the updated graph (c)….(a), (c), (a), (c).. .Just a minute, aren’t they very similar apart from the flat bit at the end. Hang on a minute, what about those 2 entirely different looking graphs in the Independent? After a long hard look I’ve spotted it. Steve Connor at the Independent has decided to change the temperature scale on the 2nd graph thus creating the illusion of dissimilarity. I wonder what the 2nd graph would look like with the original scales of the 1st graph? An unfortunate oversight I am sure. But wait, the exaggeration is made to look even worse. While the Solar activity is having a rest on its plateau we are reminded of the “Roadrunner” temperature which zooms past, onwards and upwards, for a further 20 years. Bit difficult to compare the two sets of data here. Never mind, so long as we are left with the correct final impression that’s all that counts. So the graphs are unfortunate, what about the words? Steve Connor writes next to these 2 graphs “There is now no such correlation between the 2 sets of data, which undermines another key ‘fact’ “. O.K. let’s see if we can run the updated data (well that is my best attempts at determining the updated data – it is not that easy for Joe Public to find!) through a basic stats package. Oh dear, it would appear that the 2 sets of data have a correlation of about 0.65 with a p value of 0.023, i.e. somewhere between “significant” and “highly significant”. Right…somewhat different from “no such correlation between the two data sets”.

    So where does that leave me? I clearly can’t trust C4 i.e. Television. I clearly can’t trust the Independent i.e. Newspapers. I clearly can’t trust the “experts” who disagree with each other. I most certainly will not trust the utterances of any politician or any group with a vested interest. I guess I’ve got to work it out for myself. Well, funnily enough I think I have. You see, when I go into a crowded smoky room my body reacts to the carbon floating in the atmosphere. Also, I have noticed that at night time, when the big yellow thing in the sky has gone to sleep my body reacts again and I feel chilly. My wild guess is that probably both the Sun and the contents of the atmosphere have an effect upon temperature. I do hope I’ve got it right.

  382. Hank Roberts:

    I do hope you will consider the possibility that you have got it completely wrong.

    Have you read the AIP history page, for example, or any of the other sources linked at the right side of the main page?
    Done the math?

    Correlated fossil fuel burned per year, CO2 change
    http://www.globalwarmingart.com/wiki/Image:Carbon_History_and_Flux_Rev_png
    and aerosol change
    http://www.washington.edu/research/pathbreakers/1969e.html
    with that set of temperature charts,
    http://www.globalwarmingart.com/wiki/Image:Instrumental_Temperature_Record_png
    Compare rather than lump together the early and later times — the lines diverge where the predicted warming shows up.

    Please show your work if it’s your own, or cite it if you’re borrowing others’ work, eh?

  383. Ian:

    Eric (#381),

    I think your willingness to track down and look at the data and science itself is great! Keep it up, there should be more people like you.

    From your description, it sounds as if you ran a correlation to test for linear trend over the whole data range, in which case a significant coefficient isn’t surprising. The crucial thing here is that more advanced models, especially GCMs, aren’t simple linear models – they match the curve of observed temperature, and will even reproduce temporal and spatial patterns, in response to observed changes in forcings (e.g., solar irradiance, CO2, volcanic eruptions, etc., etc.). That’s why a divergence between solar measures and temperature over the last few decades is meaningful, and doesn’t help the solar explanation.

  384. JonL:

    In your introduction to this Blog you say,

    ‘…but if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its (sic) so small. The correct interpretation of this is well known: that there is a T-CO2 feedback…’

    So, the (800ish)-year lag is totally insignificant when viewed from a larger time scale? (The ‘T-CO2 feedback’ appears causally impossible given this lag.) I have read the rather good article on this site which tackles this counter-intuitive anomaly and have found in it a lot of ‘coulds’ and ‘mights’, but a general admission that it is an unknown http://www.realclimate.org/index.php?p=13. It also notes that the ‘first cause’ of a new (interglacial) warming trend would probably be variations in solar radiation or changes in ocean behaviour. It is unclear on this, as it is on other points. The solar radiation ‘forcing’ issue in general I suppose is one of those areas of uncertainty.

    But the lag does exist, then, even if it is here dismissed as insignificant when viewed in a larger time scale. As you put it, the ‘correct’ interpretation is the – well – correct one, I guess!

    Fine, I am not trolling around here. I have a genuine interest, as all responsible people do, and I don’t want to ‘get into it’ with science journalists or climate-studiers who seem to spend most their lives rebutting people they (rather hastily in my view) adjudge ‘deniers’, if this site is anything to go by, and have therefore become rather good at it.

    I have just a couple of concerns, though: If we can ignore an 800-year lag between CO2 and temperature rise as insignificant when reviewed on a geological time scale – regarding it as the beginning of a 5000-year cycle during which CO2 takes over the warming process (at c.4200 years) – then why can’t we ignore recent tiny temperature variations on similar grounds? Or, why can’t we see current trends as merely the beginning of a new 5000-year interglacial cycle – which began some time ago, during which relatively small contributions from human activities will merely foreshorten the 800-year lag (by how much is another unknown/unknowable, it seems)? And why can’t we assume that it hasn’t been kick-started by solar radiation or some other ‘forcing agent’ just as it has in the past?

    I can comprehend the notion that a higher CO2 level might conceivably have ‘kick-started’ this latest trend itself. But apparently this would be remarkable as it has never been proved that CO2 actually could ever act as a ‘kick-starter’ for such a trend in the first place. Maybe this last point can be clarified for me. I am sure someone who is much more informed will have a wonderful answer to all these no-doubt silly reactions (which are really more about method than topic). I look forward to reading it.

    Lastly, although it is self-evident that future generations will have to ‘pay the price’ for a warming planet regardless of what caused it, what I do object to is that we mere ‘civvies’ are expected to pay for all this one way or another in any case right now; that it is some kind of ‘moral responsibility’. It really is not that simple. And for myself, a natural sceptic, I suspect we will pay inevitably and soon, but far more in treasure than in pain, although the two are never mutually exclusive, given the current political ‘climate’. That is not to say that there are not people in the developing world who could conceivably pay in pain – if they aren’t already – if the western governments proclaim they shall not ‘develop’ (ie: make electricity and create sanitation for future generations using all means possible).

    But I still appreciate what you at realclimate are trying to do – keep ordinary people reliably informed about the state of the research, and engage in some debate, even if it is from the position of a particular mindset (that AGW is completely irrefutable – something with which I am bound to disagree. But, of course, I do agree that GW is completely irrefutable – just for the record).

  385. Hank Roberts:

    Eric:
    http://upload.wikimedia.org/wikipedia/en/a/a2/Climate_Change_Attribution.png

  386. Hank Roberts:

    A perhaps useful definition, found here: http://www.plexoft.com/cgi-bin/M.cgi

    Mathematics
    In a speech in 1913, Cassius J. Keyser (J. does not stand for Julius) explained:

    “But does not the lawyer sometimes arrive at correct conclusions? Undoubtedly he does sometimes, and, what may seem yet more astonishing, so does your historian and even your sociologist, and that without the help of accident. When this happens, however, when these students arrive, I do not say at truth, for that may be by lucky accident or happy chance or a kind of intuition, but when they arrive at conclusions that are correct, then that is because they have been for the moment in all literalness acting the part of mathematician. I do not say this for the aggrandizement of mathematics.”

  387. proffate:

    What’s a “scientist.” anyway? Are acolytes required to undergo arcane rituals in order to gain access to the mysteries of “science”?

    Nope. It’s all out there for anyone who wants to look it up.

    So I looked it up. My conclusion was that the global warming bruhaha was political, rather than scientific.

    When in doubt, follow the money. Tons of cash is going to researchers who put “warming” into the descriptions of their research.

    What’s worse is the “cure.” A Global Warming Tax is being proposed for anyone who has the audacity to use energy for heating, cooling, driving or any other activity associated with life in an industrialized nation. If global warming guilt could be translated into cash, somebody is going to make a bundle!

    This money would go to an unelected body who could pay themselves any salary they saw fit, while claiming “nonprofit” status.

    My background is in advertising/marketing, rather than science (although I can claim a 99 percentile on the ACT test). So I’m able to recognize a moneygrubbing scam when I see one.

    Global warming is that scam. Guard your wallets!

  388. Gavin McP:

    In case you didn’t catch it on the other thread, Chris Merchant of Edinburgh University offers an eloquent rebuttal to some of the claims made in Durkin’s film.
    http://www.geos.ed.ac.uk/homes/chris

    (115 MB download)

  389. Mike Donald:

    #387
    That ACT. Does that stand for Associated Conservatives of Texas or Alliance for Cannabis Therapeutics?

    I dunno.

    Mike

  390. Gavin McP:

    #388: Sorry to correct my own post – I should point out that Merchant appears to have made an error in his analysis of the solar-T curve (as noted here, based on William Connelly’s analysis here).

  391. Paul Swanson:

    Where did the carbon in coal and oil come from? There can be no denying that it came from atmospheric CO2. If up until recent times the biosphere was a net sink for carbon, then a reversal of that process just gets us back to were we started. The real issue is how the perturbation of current levels effects the ecosystem, and what will be new steady state. We will adapt; that is what we do best. Adapting to change is why we are all not trilobites.

    p.s. Would have it been ethical to prevent an ice age?

  392. Barton Paul Levenson:

    [[The message is always the same. Why is it always presented as a dead certainty?]]

    Probably because, at this point, it’s pretty much a dead certainty.

  393. Barton Paul Levenson:

    [[So I looked it up. My conclusion was that the global warming bruhaha was political, rather than scientific.]]

    You can’t have looked very far. Did you read any articles in peer-reviewed journals, such as Science, Nature, the Journal of Geophysical Research, Geophysical Research Letters, or the Journal of Atmospheric Sciences? Did you learn all the science, say by going through Hougton’s “The Physics of Atmospheres” and working all the problems?

    [edit]

  394. Barton Paul Levenson:

    [[ why can’t we assume that it hasn’t been kick-started by solar radiation or some other ‘forcing agent’ just as it has in the past?]]

    Because we’ve measured the isotope ratios and know that the new CO2 in the air is almost all from burning fossil fuels.

  395. Barton Paul Levenson:

    [[Where did the carbon in coal and oil come from? There can be no denying that it came from atmospheric CO2. If up until recent times the biosphere was a net sink for carbon, then a reversal of that process just gets us back to were we started. The real issue is how the perturbation of current levels effects the ecosystem, and what will be new steady state. We will adapt; that is what we do best. Adapting to change is why we are all not trilobites.

    p.s. Would have it been ethical to prevent an ice age? ]]

    The end state is NOT the only thing that’s important! How we get there matters as well! The future Earth with 295 K mean global annual surface temperature and 75% ocean coverage may be a nice place, but if the transition is fast enough, it will completely disrupt our agriculture and our economy.

    Achieving 120 mph because you’re in an airplane taking off is good. Achieving 120 mph because you fell off the Empire State Building is bad.

  396. Hank Roberts:

    CO2 and oceans: http://www.pmel.noaa.gov/co2/co2-home.html

  397. Hank Roberts:

    PS — coming soon — don’t have time to hunt for a link for this, just flagging for contribs to consider if interesting

    Full Committee Hearing: Future of Coal
    Thursday, March 22, 2007
    02:30 PM
    Energy Committee Hearing Room – SD-366

    The purpose of the hearing is to receive testimony on the �Future of Coal� report recently published by the Massachusetts Institute of Technology.

  398. John L. McCormick:

    RE # 397

    Hank, thanks for the heads up on the Senate Energy Committee hearing on the Future of Coal report.

    Excuse the long URL but it should take you to the Senate announcement of the hearing and a link to the report, which, IMO, is a fabulous piece of work and a must read.

    http://energy.senate.gov/public/index.cfm?FuseAction=PressReleases.Detail&PressRelease_id=235242&Month=3&Year=2007&Party=0

  399. SomeBeans:

    #390: Gavin McP
    Regarding Chris Merchant’s reconstruction of the solar-T curve. Doesn’t the 11 point moving average which forms the first step of the analysis give you the solar cycle length (or something proportional to it) from the sunspot number?

  400. James:

    Re #391: [Where did the carbon in coal and oil come from? There can be no denying that it came from atmospheric CO2. If up until recent times the biosphere was a net sink for carbon, then a reversal of that process just gets us back to were we started.]

    I suppose that’s technically sort of correct, but what you’re not seeing is the timescale. About half a billion years ago (give or take) the Earth’s atmosphere had a lot of CO2 but no oxygen. (The sun was dimmer then, too.) Then the first photosynthesizing plants started taking CO2 and turning it into oxygen, in the process of which some died, and their bodies got buried and eventually turned into coal and oil. Likewise, some kinds of sea life use CO2 to build shells, which eventually turn into rocks. Since volcanos and such keep adding a bit more CO2, eventually you get an atmosphere which has a fairly constant small amount of CO2. Meanwhile, life has evolved to prosper in this sort of atmosphere, and the sun’s gotten warmer so the temperature stays comfortable.

    So over 500,000,000 years, the biosphere has gradually taken most of the CO2 out of the air, and turned it to coal and oil. Now humans are digging up all that fossil carbon, and putting it back in the atmosphere a million times faster than it came out. Burn it all, and we might indeed get back where we started, to a planet with lots of CO2 but no oxygen, and a warmer sun. Not a place most of us would want to live, even supposing we could.

  401. Nathan:

    “…if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its so small.”

    You may be right on the issue, but this is shoddy reasoning. Who cares whether you can see the lag on the 400-800 kyr graph? Does it disappear if you can’t see it?

    You still haven’t answered the fundamental question: If CO2 drives temperature change, why does the temperature change appear in the record before the C02 increase?

  402. Dave Rado:

    Re. 401 This question has been exhaustively answered over and over again in the past few days, in this and in other realclimate threads. How many times do people here have to answer the same questions? See for instance here (wait for the page to fully load � it will eventually jump down to the relevant posting).

  403. Robin Levett:

    Nathan (#401):

    An even shorter answer to your question is: No-one claims that CO2 is the only driver of temperature change.

  404. Gavin McP:

    #399: “Regarding Chris Merchant’s reconstruction of the solar-T curve. Doesn’t the 11 point moving average which forms the first step of the analysis give you the solar cycle length (or something proportional to it) from the sunspot number?”

    From watching the presentation, the graphs look similar but not identical. Come to think of it, I don’t understand why the two graphs should look so similar – can anyone enlighten me?

  405. James:

    Re #401: [You still haven’t answered the fundamental question: If CO2 drives temperature change, why does the temperature change appear in the record before the C02 increase?]

    Because CO2 only drives temperature change when it’s in the atmosphere. Before humans came along and started burning fossil fuels, the only way to increase the amount in the atmosphere was for something else to warm up the planet and cause CO2 to be released from warmer oceans.

  406. Barry Wells:

    Gavin, In your article SWINDLED! you make the following observation ,’the 40-70 cooling type period is readily explained, in that the GCMs are quite happy to reproduce it, as largely caused by sulphate aerosols’. Do you know of any work / data that might have been produced which investigates any possible effects on the climate relating to the 528 atmospheric Nuclear bomb tests that took place betwen 1945 and the mid 1960’s. A time line that covers the major part of the period with a depresion of the temperature signal.

    [Response: What mechanism would you propose? My sense is that anything sensible would end up being completely negligible. – gavin]

  407. Flightless Bird:

    I’ve been posting on a general message board (hence the silly name) trying to explain some of the arguments about global warming. I got asked about the lag between T and CO2, and after reading some (but not all, I couldn’t get onto the site because it was too busy) of the above responses, made the post below. I suppose I should have asked you gus first, but is it a corrct explanation?

    “First, it seems pretty clear that in the recent geological past that CO2 concentrations have been *lagging* temperature (T) changes by about 600-800 years. However:
    (1) This is not the primary scientific evidence for CO2 being responsible for the current warming.
    (2) It is also not inconsistent with CO2 being responsible for the current warming.

    The important point is that causation does not work in just a single direction between T and CO2, but in both directions: T has an effect on CO2, and CO2 has an effect on T. We know this from well understood physical and chemical properties that can be measured in the laboratory: as you warm up water (on a big scale â?? the oceans) it gives off the dissolved gases, so increasing T increases CO2 in the atmosphere; and CO2 molecules absorb long-wave radiation (ie heat radiation) and then re-radiate it (and in the atmosphere since half of it gets re-radiated downwards this tends to keep the earth warmer than it would otherwise be), so that more CO2 in the atmosphere tends to increase T.

    Systems in which causation works in both directions are not unfamiliar to us. Think about education and wealth: better educated people tend to end up with better jobs and as a result become wealthier; on the other hand, wealthy people are able to buy their children better education. So if causation works in both directions, what determines which will lag the other one? Imagine that we could play God and change either education or wealth levels (I donâ??t mean to cause offence, what Iâ??m simply trying to do is to imagine being able to change one of these two independently of the backwards and forwards causation between wealth and education). Say we made wealth go up and down cyclically over a period of 100 years. Itâ??s not difficult to see that weâ??d expect cyclical variation in education that lagged behind the variation in wealth. Now imagine that we make education go up and down cyclically instead: weâ??d then expect wealth to go up and down cyclically, but lag behind education. So which of the two variables leads, and which lags, depends on which is being â??externally drivenâ??.

    OK, now back to CO2 and T. Over geological time, temperature is externally driven by variations in solar heating caused by orbital variations (no, not the sunspots that the program talked about): in these long cycles, T tends to drive CO2, and CO2 lags by 600-800 years. But since the industrial revolution man has been adding huge quantities of CO2 to the atmosphere. (We know that, at the very least, because there are good records of how much coal and oil have been extracted (and subsequently burnt.) This is now acting as the dominant driver, swamping the gentle decrease over the last 8000 years in temperature that would have been expected from the stage that we are currently at in the solar heating cycle.

    This is why the fact that CO2 lags T in the recent geological past is not inconsistent with CO2 being the *cause* of the current increase in T.”

  408. Nathan:

    #s 402 and 403:

    I do not object to the claim that C02 is a greenhouse gas and, all else being equal, more C02 will lead to warmer temperatures. That is why I prefaced my comment with “you may be right on the issue.” I object to two claims:

    1. That the importance of the 800 year gap is somehow mitigated by the fact that it isn’t obvious on a plot of poor enough resolution, which is just downright silly, and

    2. That a plot showing the correlation of temperature and C02 through geologic history constitutes *evidence* that rising C02 will in fact cause rising temperatures. Most popular presentations on global warming and not a few allegedly technical ones entirely omit the elementary point that correlation is not causation.

  409. Hank Roberts:

    Nathan, the causation is basic physics, see the AIP history, search for “Arrhenius” — this just isn’t in doubt, even before the uncontrolled experiment by burning fossil fuels put it to experimental test.

    It’s a chicken and egg problem, you can start with either one and get more.

  410. Pete Burns:

    Not too many decades ago I can remember reading with some alarm a full two page newspaper article by eminent scientists explaining how the world was facing an imminent ice-age. Since the place I live was under 300 feet of ice less than 10,000 years ago I thought of moving. Seems things (or funding?) has run out on that one. Anyway following “the program” I have been doing a bit of looking around regarding anthropomorphic induced climate change and would appreciate comments on the following extract from a site with it’s own opinions. Thanks in anticipation.

    “The focus solely on CO2 is fueled in part by misconceptions. It’s true that human activity produces vastly more CO2 than all other greenhouse gases put together. However, this does not mean it is responsible for most of the earth’s warming. Many other greenhouse gases trap heat far more powerfully than CO2, some of them tens of thousands of times more powerfully. When taking into account various gases’ global warming potential – defined as the amount of actual warming a gas will produce over the next one hundred years – it turns out that gases other than CO2 make up most of the global warming problem.

    …. the fact remains that sources of non-CO2 greenhouse gases are responsible for virtually all the global warming we’re seeing, and all the global warming we are going to see for the next fifty years. If we wish to curb global warming over the coming half century, we must look at strategies to address non-CO2 emissions.

    Methane

    By far the most important non-CO2 greenhouse gas is methane, and the number one source of methane worldwide is animal agriculture.

    Methane is responsible for nearly as much global warming as all other non-CO2 greenhouse gases put together. Methane is 21 times more powerful a greenhouse gas than CO2. While atmospheric concentrations of CO2 have risen by about 31% since pre-industrial times, methane concentrations have more than doubled. Whereas human sources of CO2 amount to just 3% of natural emissions, human sources produce one and a half times as much methane as all natural sources. In fact, the effect of our methane emissions may be compounded as methane-induced warming in turn stimulates microbial decay of organic matter in wetlands – the primary natural source of methane.”

    [Response: I greatly doubt that you saw any such article by ‘eminent scientists’ – but if you can find it, I’d be interested. It is not true that the non-CO2 gases are more important than CO2, currently they are slightly less, but the growth rate of those forcings is actually less than CO2. Methane is important, and the flattening of it’s concentrations in recent years is a small ray of sunshine in the whole situation. The statement that the non-CO2 gases are responsible for all recent climate change and for all projected growth is simply false. – gavin]

  411. Walt Bennett:

    Re: #410,

    “I have been doing a bit of looking around regarding anthropomorphic induced climate change and would appreciate comments on the following extract from a site with it’s own opinions.”

    My comment is, there is nothing controversial there. Dr. James Hansen of NASA-GISS said the same things in 2000:

    Global Warming in the 21st Century: An Alternative Scenario
    http://pubs.giss.nasa.gov/abstracts/2000/Hansen_etal_2.html

    Abstract:
    A common view is that the current global warming rate will continue or accelerate. But we argue that rapid warming in recent decades has been driven mainly by non-CO2 greenhouse gases (GHGs), such as chlorofluorocarbons, CH4, and N2O, not by the products of fossil fuel burning, CO2 and aerosols, the positive and negative climate forcings of which are partially offsetting. The growth rate of non-CO2 GHGs has declined in the past decade. If sources of CH4 and O3 precursors were reduced in the future, the change in climate forcing by non-CO2 GHGs in the next 50 years could be near zero. Combined with a reduction of black carbon emissions and plausible success in slowing CO2 emissions, this reduction of non-CO2 GHGs could lead to a decline in the rate of global warming, reducing the danger of dramatic climate change. Such a focus on air pollution has practical benefits that unite the interests of developed and developing countries. However, assessment of ongoing and future climate change requires composition-specific long-term global monitoring of aerosol properties.

  412. Dan:

    With a lot of help from realclimate.org, I think I was successful in convincing a group of hard conservatives that GGWS was a total propaganda piece. Intially they were convinced this was groundbreaking info. This page was exactly what I needed. Thanks guys!

  413. Hank Roberts:

    Pete, what you quote contains statements about the different gases and what part of warming they’re responsible for that don’t sound familiar to me — where are you getting your beliefs about this?

    All need attention. You’re basically restating James Hansen’s ‘Alternative Path’ proposal, you know? This has come up before here, fairly often.

    I tried to look up your numbers and can’t find them. What’s your source?

    I found this, for example:
    “carbon dioxide emissions account for 80% of the contribution to global warming of current greenhouse gas emissions, as compared with 57% of the increase in radiative forcing for the 1980s.”
    http://www.nature.com/nature/journal/v344/n6266/abs/344529a0.html

  414. Hank Roberts:

    Pete, it appears there are only two websites where Google finds what you’re quoting.
    Do you know who these people are? You can look them up. You should, if you’re not one of them.

  415. Hank Roberts:

    Gavin, try dropping some chunks of the quote in #410 into a search engine; this gets intriguing.

    I found bits of it attributed to James Hansen, only in the last few days (no cite) and large chunks of it posted in various supposedly animal-rights and vegetarian sites, several of them recommending the ‘Swindled’ video.

    All very recent. I didn’t get to checking who owns the various IP addresses used, but it’s most curious to see this sort of thing suddenly showing up in a lot of places all at the same time. It’s in several threads here at RC as well.

  416. Hank Roberts:

    Okay, this really smells funny. Googling a chunk of that text quoted, I find part of it attributed (with no cite) to Dr. James Hansen, at one of these sites (flaggman.wordpress) — alongside recommendations of the Swindled film and the Friends of Science site as well.

    Other sites mention Hansen along with repetitions of the text. It’s all basically claiming Dr. Hansen doesn’t think CO2 is responsible for warming.

    Disinformation?

  417. P. Lewis:

    Before ‘everyone’ starts using the term, can I just say that you mean anthropogenic (originated by humans) not anthropomorphic (having or representing a human form). Clouds may occasionally be anthropomorphous, as might the edges of melting glaciers I suppose, but that would be about the limit.

  418. P. Lewis:

    You might find the national figures issued by the US DOE instructive and informative, since these are generally broken down into actual physical masses of the individual (or groups of) GHG components and in terms of CO2 equivalents.

    And bear in mind that the fate of all CH4 emissions to the atmosphere is CO2 + H2O (over about a decade, IIRC), but offhand I can’t recall whether that’s taken account of when arriving at the GWP of CH4.

    [Response: One molecule of CH4 makes one molecule of CO2, and so the concentration of methane ~1.750 ppm only makes 1.750 ppm extra CO2 when oxidised – compared to mean concentration of 380 ppm, this is trivial. – gavin]

  419. P. Lewis:

    Re# 418 response

    Thanks for fleshing that out.

  420. Leo:

    #417, #411

    – “can I just say that you mean anthropogenic (originated by humans) not anthropomorphic (having or representing a human form).”

    I think that’s a bit of a bold assumption. My assumption was he was being facetious.

  421. P. Lewis:

    Well, Leo, that might be the case, but it bears stating since people do get it wrong and the uninitiated and uneducated propagate it.

    And picking up on #410 and the assertion of an imminent ice age of the 1970s:

    Not too many decades ago I can remember reading with some alarm a full two page newspaper article by eminent scientists explaining how the world was facing an imminent ice-age. Since the place I live was under 300 feet of ice less than 10,000 years ago I thought of moving. Seems things (or funding?) has run out on that one.

    one only needs to look at the RC article hereabouts somewhere on that issue and an analysis of this issue by William Connelly. It’s a fallacy. The race didn’t get underway; the starter never fired his pistol on this issue. Which, perhaps, highlights the adage that you shouldn’t get your science from newspapers.

  422. Mike Donald:

    Folks,

    Any else see this? Come to think of it when I hear Durkin I think of swear words too!

    Times article 15/3/07 headed:-
    “C4â??s debate on global warming boils over”

    http://www.timesonline.co.uk/tol/news/uk/science/article1517515.ece

    Quote

    Two eminent British scientists who questioned the accuracy of a Channel 4 programme that claimed global warming was an unfounded conspiracy theory have received an expletive-filled tirade from the programme maker.

    In an e-mail exchange leaked to The Times, Martin Durkin, the executive producer of The Great Global Warming Swindle, responded to the concerns of Dr Armand Leroi, from Imperial College, and Simon Singh, the respected scientific author, by telling them to â??go and f*** yourselfâ??.

    Unquote

    The article also has some debunking of the programmes’ claims.

    Cheers and keep up the good work.

    Mike

  423. Nick Gotts:

    Re #410, #411, #414, #415, #416.

    So far as I can tell, the original source for the quote in #410 is an article on the following page: http://earthsave.org/globalwarming.htm

    Headed:

    EarthSave Report:

    A New Global Warming Strategy:
    How Environmentalists are Overlooking Vegetarianism as the Most Effective Tool Against Climate Change in Our Lifetimes by Noam Mohr

    The full downloadable version cites the Hansen et al NASA report for which the abstact has been quoted, and a Hansen and Sato 2001 paper in PNAS: vol. 98, no. 26, 18 Dec. 2001, p. 14778-14783, http://www.pnas.org/cgi/ content/full/98/26/14778 (which apparently caculates the net forcing from non-CO2 GHGs to be slightly greater than those from CO2 over the period 1850-2000, when indirect effects via ozone and water vapor are taken into account). It argues that because the main anthropogenic CO2 sources also produce aerosols with a net cooling effect, warming so far is almost entirely due to other GHGs (I’d say this is a misleading way of putting the state of affairs, particularly as aerosol production can be and has been reduced for good reasons without reducing CO2); and argues that reducing methane (by going vegan) is the best short-term strategy against climate change. However, it also says:

    “While CO2 may have little influence in the near-term, reductions remains critical for containing climate change in the long run. Aerosols are short-lived, settling out of the air after a few months, while CO2 continues to heat the atmosphere for decades to centuries.”

    In sum, it’s not a scientific article, and pushes a particular line for what I’d guess are primarily non-climate related motives, but I’d say it’s by no means outright ignorant or irresponsible.

  424. Scott:

    Most people would say that the concept of global warming has put environmentalism into the big time. The green movement was not started in the seventies, rather it was returned to after years of neglect in the shadows of the industrial revolution. Its natural to be green. Environmentalism is not a political consumer driven war, its essentially respect for ones habitat.(a fundamental of survival).

    Environmental Activism that has bled into many walks of life, many age groups, many nations. So what if global warming is�nt caused by us, we may be fighting a ghost but in doing so we are relearning the respect that we lost. Not only that but as far as energy is concerned is�nt it a good thing that we diversify into renewable sources, take the dominance of these industrial behemoths away and give our communities independence and security from the whims of war lords, extremists and despotic tycoons. Our consumption of energy from its current sources is directly responsible for countless atrocities and inequalities. It is shameful to think that this fact alone, aside from global warming would not be enough cause to rework this planets energy.

    The Nasty dwindle swindle left me with this question:
    If you categorically knew that global warming was happening but it was caused by the sun, why would you make a documentary about it knowing it would have no effect other than to stifle environmental activism?

    Send your answers to channel four ratings department, its next to the big brother alter.

  425. P. Lewis:

    Re # 422 (Mike)

    I note Durkin has apologised and is quoted as saying

    “Needless, to say, I regret the use of intemperate language. It is so unlike me. I am very eager to have all the science properly debated with scientists qualified in the right areas and have asked Channel 4 if they will stage a live debate on this subject.”

    It is not clear to me what branch of science “intemperate language” belongs in. Should be a lively debate, though … after the watershed presumably.

    His thesis seems to be that “intemperate language” is OK in private e-mails but not in those likely to be published. For one so versed in the media, this seems very naive.

  426. Hank Roberts:

    Scott, you have that backwards — it’s certainly possible at some point that the physicists will tell us that our star is more variable than we’ve thought, or going into a more variable period, and so will be responsible for more of the change in climate over a shorter span of time — even so short as to be important in human plans.

    If we’ve learned all we can about how life and climate work, we’ll have a better chance of handling what surprises remain in the universe, and perhaps figuring out why there’s so far no sign of intelligent life (the Fermi Paradox).

    Don’t conflate ecology —- the science needed to understand what we’re doing, considering how fast humans are changing the basics of life on the planet — with ‘environmental activism’ (commercial and political activity that changes the world, for better or worse, intentionally or not).

    The biggest environmental changes are from business as usual. The conservatives — the conservationists — are making much less difference, and they’re saying don’t burn and eat it all, we might need some of the parts to keep breathing.

  427. Mike Donald:

    #418
    About Gavin’s response:-

    From Wikipedia

    Start Wiki quote

    The second scale is global warming potential (GWP). The GWP depends on both the efficiency of the molecule as a greenhouse gas and its atmospheric lifetime. GWP is measured relative to the same mass of CO2 and evaluated for a specific timescale. Thus, if a molecule has a high GWP on a short time scale (say 20 years) but has only a short lifetime, it will have a large GWP on a 20 year scale but a small one on a 100 year scale. Conversely, if a molecule has a longer atmospheric lifetime than CO2 its GWP will increase with time.

    Carbon dioxide is defined to have a GWP of 1 over all time periods.
    Methane has an atmospheric lifetime of 12 ± 3 years and a GWP of 62 over 20 years, 23 over 100 years and 7 over 500 years.

    The decrease in GWP associated with longer times is associated with the fact that the methane is degraded to water and CO2 by chemical reactions in the atmosphere.

    End Wiki quote

    Taking a timescale of 100 years. Methane GWP of 23
    Natural CO2 was 280-300 ppm. Present 380ppm = Man-made difference 100ppm. 23 * 1.75ppm = 40 ppm. 40/100 = 40%??? or 40/380= 11% ?

    (Or 7 * 1.75/380 = 3%).

    Sorry about the back of fag packet calcs but maybe 3% might be seen as trivial but with all this talk about tipping points etc that 11% sounds like a worry.

    I await the inevitable corrections to my howlers.

    Keep up the good work.

    Mike

    [Response: GWP is only useful for comparing future emissions of CH4 and other non-CO2 GHGs, it doesn’t tell you about the attribution to changes so far (there are complicated reasons why this is so for CH4). For the anthropogenic increase in CO2 (100 ppm) and the anthropogenic rise in CH4 (~1000ppm), the radiative forcings are ~1.5 W/m2 and 0.5 W/m2 respectively. Current growth rates though are strongly positive for CO2 (~2ppm/yr) and close to zero for CH4. – gavin]

  428. Hank Roberts:

    And — for Scott — of course scientists think about what the sun may do. Sol _is_ a variable, just not a very variable variable, on the time scale we know about.

    This is fiction, and I _think_ the Apollo rocks really weren’t as described, after a later look. But it’s within the realm of possibility.

    Knowing how the world works is the secret to having a chance of outliving it: http://homepage.ntlworld.com/adam.milner/books/inconstant_moon.htm

  429. Barton Paul Levenson:

    [[Sol _is_ a variable, just not a very variable variable, on the time scale we know about.]]

    I think Larry Niven is responsible for this popular myth, through his award-winning “Inconstant Moon.” For the record, the Sun is not a variable. It is a main sequence star. Variables are generally red giants; i.e., stars which have gone through the main sequence and are now rapidly changing their energy output.

  430. Joe (Bigsky770):

    IMO, there is something that I find strangely hypocritical about the stance of the so-called “Right Wing” RE: “The Global Warming Issue”.

    One would think that given the current (so-called) “War on Terrorism”, since it is believed that all those petro-dollars are gleefully being directed towards nations that would enjoy nothing less than the complete and utter destruction of the west and what they refer to as “the capitalist-imperialist society,” we’d at least try to double our efforts at trying to break this “Petroleum Addiction”.

    Perhaps it’s just easier for “Big Oil” to ‘go with the flow of the status quo’ then to diversify those billions in record profits towards greener technologies, never mind the thought of striking a blow against “Extremist-Islamic Terrorism,” canceling their income…

    Are you as confused as I am?

  431. Hank Roberts:

    Sol is a G-type — not a “Cepheid variable” — but G-types are variable in output, as people keep pointing out, and varying in different ways at different wavelengths, not all in a coordinated fashion.

    http://adsabs.harvard.edu/abs/2003toed.conf..403E

    A good reminder of how tentative our knowlege is, follows a discussion of what relation studies of solar and climate might have. The studies (many mentioned here in other threads) are new and tentative science:

    “… These studies, all depending upon relationships between irradiance, sunspots and faculae derived during a single solar activity cycle, or upon the still somewhat shaky calibration between measures of solar and stellar chromospheric K-line fluxes (see Hall & Lockwood 1995), must be viewed as tentative. They also illustrate that an appeal to the behavior of solar analog stars is a natural impulse. The direct comparison of solar and stellar brightness variability has, however, been slowed by the severe demands such a comparison makes on the precision of stellar photometry…..”
    http://www.journals.uchicago.edu/ApJ/journal/issues/ApJ/v485n2/35548/35548.html?erFrom=538071448004377618Guest

    Nor is Sol a “flare star” as that term is defined astronomically of course.

    Yet Sol is capable of surprisingly large flares (as in, capable of surprising us about how big, given our very limited timeline). Google “X-class flare” for some of that.

    “The largest flare in modern times was recorded in November 2003 and was estimated to be an X-40. It, too, was on the limb of the Sun and so its full impact was not felt on Earth. That flare was part of an unprecedented series of 10 major flares within two weeks; at least one Earth-orbiting satellite was disabled and one instrument aboard a Mars-orbiting craft was knocked offline….”
    http://www.space.com/scienceastronomy/050909_solar_flares.html

    I’m just saying that knowing how nature works — both our climate system and our local star — all do fascinate scientists.

    People can put a lifetime into studying something that has only a tiny, barely measurable effect on day to day life. Sometimes, later, that proves quite useful.

    Again, solar variability right now is clearly minor as a factor in the climate change we know about. Just saying, scientists don’t ignore this kind of thing, it’s fascinating.

    http://www.agu.org/history/SV.shtml (fairly old info)
    http://www.ucar.edu/communications/factsheets/sun/

  432. tamino:

    The sun is not a variable star in the traditional sense. It can be called “micro-variable” because its output does vary, but only slightly (as measurements of total solar irradiance confirm), but its variability is on the order of 0.1%, or (using the usual astronomical measure of brightness) about 0.001 magnitudes. At that level, only the most sensitive photometers would be able to detect its variability. Traditionally, variable stars are those whose brightness varies by around 0.1 magnitude or more, which means that brightness variations are (sometimes only barely) perceptible to the naked eye.

    Not all variable stars are red giants. In fact there are two broad classes of variables: intrinsic and extrinsic. Intrinsic variables change brightness due to changes in the star itself; this can include such phenomena as pulsation, mass transfer, starspots, or explosions (supernovae are the brightest variables of all). Extrinsic variables don’t really vary, but they seem to due to changes in viewing conditions. The best-known extrinsic variables are eclipsing binaries, in which two (or more) stars orbit each other and we note brightness changes as they take turns eclipsing other (along our line-of-sight).

    Variable star astronomy is one of the fields in which amateur observers make a tremendously valuable contribution. Those who are interested can visit the American Association of Variable Star Observers for lots of information.

  433. Barton Paul Levenson:

    tamino — right, I should have remembered things like eclipsing binaries. I just meant Niven wasn’t really accurate in calling Sol “a 4% variable star.” It isn’t.

  434. Hank Roberts:

    CNN is carrying the Congressional hearing with Lomborg right now, the congressman is referring to the “Maulder” [sic] minimum, quoting a Dr. Hall, asking about suggestions of a possible longterm disappearance of sunspots in the near future and a longterm cooling to come, and referring to melting poles on Mars.

    “I am not a scientist” Lomborg replies … “we might be surprised in 20 years and know something else” but right now the best information we have is the IPCC.

  435. Jerry Cunningham:

    I ‘m not a scientist , biologist or any other kind of “gist” or ” tist ” , but I wonder how the same bunch of experts that can’t tell me if it is going to rain next Tuesday can predict what the weather will be like in 50 years. Also , according to most historic data ( I don’t doubt it ONE bit , I can SEE the mountains ), the spot where I am currently sitting pecking on this keyboard was under about 500 feet of ice about ten thousand years ago. Where did the ice go ? What caused THAT global warming trend ? Please answer if you can….THANX

    [Response:Milankovitch – gavin]

  436. Michael Tobis:

    Many of the conversations in this particular thread have been alarming in the failure to come to terms with nomenclature. I see lots of instances of people talking past one another.

    The case of Reid vs almost everyone else is especially disconcerting. Reid is trying to explain a very rigorous body of mathematical theory that is at the core of electrical and mechanical engineering curriculum. Dismissing his comments (as Gavin does in the response to #228) greatly damages the credibility of RC and of climate science.

    The distinction of positive vs negative feedback as used in climate science is, I think, identical to the distinction between amplification and attenuation as used in engineering, and NOT identical to the distinction between positive and negative feedback as used by engineers.

    Reid claims to be among the people who have a very rich theory in which these concerns are central, and he talks the talk well enough that I am entirely convinced. To dismiss him without trying to patch together what he is actually trying to say is a very serious error both intellectually and strategically.

    RC editors have taken on a very serious mandate without pay or reward, and I join others in greatly appreciating it, but it is a mission that needs to be taken seriously. While it is surely hard to keep the conversations productive, it’s particularly unfortunate when the editorial green ink pops in and contributes to the confusion rather than allaying it.

    [Response: Michael, I appreciate your comments, but I did point Reid to an excellent explanatory text which he did not read. This stuff is not difficult, and given the constraints on our time, asking someone to read the answer to his questions is not too much to ask. -gavin]

  437. Chuck Booth:

    Re #435

    I don’t think any climate scientist would claim to be able to predict the weather 50 years from now. You are confusing weather and climate.

  438. Dano:

    I’ve been busy and haven’t followed RC’s threads, but MTs comment popped up and I agree with his thesis. I state, as an ecosystem guy, that ecological processes have been give short shrift in answering Reid’s questions, which should be given more prominence and reflection in the climate community. That is: gawdawful interdisciplinarity a-gaaaain. I know, I know.

    Nonetheless, I hope Reid is still lurking and reads this from an ecosystem guy: there is merit in what you say and likely biota formed the 280 ppmv CO2 limit. Biota utilized the increase and did their thing. The human organism has tilted the CO2 ppmv balance and thus we are where we are today. Oh, yes, I want you to ask me where is the empiricism that biota have been the top-down control. Please ask.

    Best,

    D

  439. Barry:

    I would recommend reading Dr.Theodor Landscheidt’s “Solar Activity: A Dominant Factor in Climate Dynamics.” Future little ice-ages will come again and so will global warming trends.

  440. Hank Roberts:

    > The distinction of positive vs negative feedback as used in climate science is, I think,
    > identical to the distinction between amplification and attenuation as used in engineering,
    > and NOT identical to the distinction between positive and negative feedback as used by engineers.

    Flag that somehow for inclusion in a Glossary, or a Wikipedia article, if any editor’s reading this and confirms it — that sort of thing is invaluable (was it Confucius who made rectification of names the first priority?).

    Visitors ought to be warned that climatology — like any other science — requires learning more new terms than a year or three of study of a new language, and often the same words used differently elsewhere.

    “Lessons learned” maybe. But I appreciate, just as a reader, how tired the regulars must get and how hard it often is to know where a new poster is coming from and how willing they are to read a bit and learn from what’s all around them here. Banging on the counter for fast service is hard to reward, eh?

  441. Hank Roberts:

    Landscheidt was last famous for litigation, if I recall, not for science.

  442. Hank Roberts:

    Oh, silly me, I forgot his astology credentials (sigh). Should’ve googled first.

  443. Barton Paul Levenson:

    [[ I wonder how the same bunch of experts that can’t tell me if it is going to rain next Tuesday can predict what the weather will be like in 50 years. ]]

    There’s a difference between weather (day to day variations, which are hard to predict) and climate (regional averages over 30 years or more). We can’t predict which uranium nucleus will decay next; it’s probabilistic at the most basic level of reality. But given a lump of uranium large enough to see, we can predict with extremely good accuracy how much will be left after a given period of time.

  444. Barton Paul Levenson:

    [[I would recommend reading Dr.Theodor Landscheidt’s “Solar Activity: A Dominant Factor in Climate Dynamics.” Future little ice-ages will come again and so will global warming trends. ]]

    I read it years ago, when it was posted on John Daly’s warming-denial site. It’s no more accurate now than it was then.

  445. P. Lewis:

    Re # 443 (Mike)

    Yes, I know he hasn’t apologised for “the” programme. There’ll likely be icebergs in Hades before that happens. That wasn’t the point of my post. It was all about his “intemperate language” usage (thanks for spotting the story, btw) and the naivety of thinking (such newsworthy) e-mails would remain private. It was also about his seemingly newfound eagerness “to have all the science properly debated with scientists qualified in the right areas”, which in the context of his polemic fiction is truly laughable.

  446. Leo:

    #447, 443&c

    But surely better to let him enter into open and free debate than it would have been to prevent him speaking in the first place. I couldn’t be further from Mike’s view that C4 should somehow be prevented from giving a voice to this sort of dissent.

    The discussions prompted by this programme, not only here but across the media and down the pub are proving to be good, fair and enlightening.

    Through openness and debate the truth will prevail. Whatever it is.

  447. P. Lewis:

    But surely better to let him enter into open and free debate than it would have been to prevent him speaking in the first place.

    But one of the main points of this thread has been about Durkin not really entering debate (the programme was a jaundiced, polemic piece) and Mike’s Times link is about not wanting to debate (telling people to go and fornicate elsewhere).

    The discussions prompted by this programme, not only here but across the media and down the pub are proving to be good, fair and enlightening.

    That it has engendered debate on blogs such as this one might well be good, but I read the 30-odd comments after the Times article that Mike linked to, and they were largely in support of the position Durkin set forth, in spite of the actual tenor of the Times article’s anti-Durkin position that those commenters were commenting on! The general level of ignorance made for depressing reading.

    C4 is a TV company with a public service broadcast remit; in airing this WAG production, C4 has done the UK public a great disservice, especially if it has left the lasting impression that AGW is a swindle (and judging by the Times correspondence that is indeed the case).

    Even if Ofcom complaints are upheld, most of those who’ve watched Durkin’s poison will be like those commenters at the Times and will take some shifting in their erroneous views. And Durkin’s poison is now on the Web in video form to win over the uneducated and ineducable, much like the 9/11 and Diana conspiracy theory videos are by the demented conspiracy theorists that abound.

    If Durkin had wanted a proper debate about aspects of AGW, he could have built a programme around the likes of Pielke Snr, rather than around “the usual suspects”, but that would not have played along with Durkin’s preconceived notions and political outlook, it seems.

    You don’t inform and engender proper debate by publishing lies, which is what Durkin has done. Durkin is the swindler.

    Thankfully, it seems, our politicians generally have more sense, which is pretty much an unusual state of affairs in the UK (he says sarcastically).

  448. Robin Levett:

    Leo

    I don’t read Mike as wanting to stop C4 giving voice to dissent – he just wants them to stop giving a platform to dishonesty.

  449. Leo:

    But who’s to police the difference between dissent and dishonesty? More half-knowledgeable media types? Do you really want that?

  450. Joel Shore:

    Re #435 (Jerry Cunningham):

    (1) To understand the difference between weather and climate, consider the following point: You might not have much confidence in the weather forecast for next Tuesday…or certainly not for several months in the future. However, I assume you would believe me when I forecast that(assuming you live in the mid-latitudes of the Northern Hemisphere) the average temperature in July is highly likely to be warmer than the average temperature in April which is highly likely to be warmer than the average temperature in January (assuming you live in the mid-latitudes of the Northern Hemisphere).

    (2) In regards to ice ages: Many skeptics seem to believe that the idea that the climate has changed dramatically in the past without human intervention is strong evidence that we humans are not causing climate change now. However, this logic is faulty to the point of being essentially backwards. In fact, what the climate oscillations in the past allow us to determine is how sensitive the climate is to perturbations (measured as changes in “radiative forcings”). For example, for the rise out of the last ice age, we can estimate the forcings and the temperature change that produced them. We also know quite accurately what the radiative forcing due to a given increase in CO2 is…so we can figure out how large a perturbation we are producing on the climate system. And, the answer is that it is pretty large, e.g., a doubling of CO2 levels produces a perturbation that is around half or so of the perturbation that took us from the last ice age to the present climate! That ought to give you pause when you think of all that ice that used to be on top of your present location. (And, by the way, unless you were on the very tail end of the glacial extent, I think the thickness of ice above you was likely about 10 or 20 times as large as the 500 ft you mentioned.)

    (3) As a final point, it is worth noting that past climate changes such as the changes from ice ages to warmer interglacial periods and the reverse generally took place over fairly long periods of time (although there may have been some more abrupt climate shifts too)…e.g., the temperature generally rose about 0.1 C per century. By contrast, in the last century it rose about 0.6 or 0.7 C…and will likely rise considerably more in the current century. (The current rate of change over the past few decades corresponds to close to 2 C per century.)

  451. Robin Levett:

    Leo #449:

    Can we not expect them to learn from experience? this isn’t the first time they’ve got burned by Durkin.

    The problem is that they are still defending Durkin – Hamish Mykura wrote to the Independent defending it as a “polemical film which contributed to the climate change debate”; and went on to defend the use of the fraudulent 20th century temperature graph.

    They should stop being “half-knowledgeable media types” and actually learn a little about the subject upon which they are commissioning films so that they can actually judge whether they actually contribute anything. It’s not as if there are no resources out there available to the lay reader.

    They should also learn that “polemical” isn’t supposed to mean “dishonest”.

  452. Hank Roberts:

    Leo — you police the difference. When you see people referring to that program or hosting copies of it, after you’ve understood the problems with it, point them out. You have to make up your own mind and you can read the science and decide who is giving you honest answers regardless of their politics.

    Remember — “Just because you’re on their side, doesn’t mean they’re on your side.” People lie to get political support. Read the science instead of the rhetoric and be willing to say ‘ouch’ when it conflicts with what you wish the world were like.

    Nature isn’t fooling.

  453. Leo:

    Actually, I imagine C4 are rather pleased with this film. Viewing figures for the first transmission matched the drama on ITV1. But I bet they’re kicking themselves they didn’t cram it full of 4×4 ads.

    They should stop being “half-knowledgeable media types” and actually learn a little about the subject upon which they are commissioning films so that they can actually judge whether they actually contribute anything. It’s not as if there are no resources out there available to the lay reader.

    Perhaps they should, but they’re not going to are they? So we need some other way to deal with it.

  454. Mike Donald:

    #445 to #452

    Gents,
    Sorry for messing up the link stream. My original comment wrongly implied that C4 had received taxpayer’s money so I asked RealClimate to delete it which they kindly did. But in today’s Guardian

    http://www.guardian.co.uk/g2/story/0,,2039587,00.html

    Quote

    Channel 4 is awaiting the results of a financial review by Ofcom, in which it has been lobbying for a public subsidy of £100m to fund its digital ambitions.

    Unquote

    After such vile misrepresentations in the programme I don’t want to give C4 money. If people want to believe in flat earths, 9-11 conspiracies etc that’s harmless to me but GW tripe is different. We’re all on the same planet (at least physically) and these programmes help delay effective action so it impacts on you, me, all of us. And the poorest in the world are already being hurt. So I want to get back at them.

    Aim straight for their wallet, do not pass Go, do not collect £200. Now what’s your MP’s address?

    Regards

    Mike

  455. Mike Donald:

    Chaps,

    And reading the Guardian article further we find the following

    Quote
    But Channel 4 is not a privatised broadcaster. – yet. It’s more important than that. It is owned and operated by the Channel 4 Television Corporation, whose board is appointed by Ofcom in agreement with the culture secretary.
    Unquote

    And the culture secretary is Tessa Jowell who represents the safe Labour seat of Dulwich and West Norwood. Place your bets on the financial overruns to Channel 4!

    Regards

    Mike

  456. Jim:

    Almost exactly 29 minutes into the documentary, a graph is shown of sunspot activity and temperature. Curiously, the curves don’t end at the same point. The solar activity curve ends around 1978, and the temperature curve continues until approximately 1985. I believe that they deliberately truncated the data right at the point that it would have diverged. What’s worse is that this happens to be the most recent 20+ years’ worth of data, which is the best example of a warming anomaly. This appears to me to be an egregious error (lie) of omission. This is, in my mind, their worst failure. It represents their central counter-argument, and it’s based upon altered/truncated data.

  457. Leo:

    Let’s keep this in perspective.

    This film has been widely criticised. It is full of holes, has been easily knocked down as insubstantial. It has failed to change the now orthodox view that AGW is a real threat.

    Whether you believe any of its contents or not, it is definitively NOT making governments lessen their plans for reducing CO2 emmissions. That much is pretty clear.

    Nobody (not even Durkin) ever suggested it’s the last word on the subject. And importantly nor is the current consensus.

    Debate about the detail of GW theory will and should continue. Clearly nobody can claim to fully understand all the processes involved. But still, Mankind is acting on the best information we have.

    As science continues to hone theory about what is happening to this planet we will adjust our behaviour to match. Mankind has proved to be very good at preserving its interests, I see no reason to doubt that will continue.

    Whatever we think of this film, it’s a small part of a much bigger picture. A vanishingly small percentage of the world’s population have even heard of it. Don’t let’s give it more credit than that.

  458. P. Lewis:

    MI: V synopsis. Your mission, should you choose to accept it, is to go to Mike’s Times link (noted above) and to convince one of the more rabid of the Durkin believers to see the error of their ways.

    Good luck!

    This message will self-destruct, in time.

    Never underestimate the power of the televisual medium … advertisers don’t, for a reason: witness, for example, the success of the general pseudoscience in attracting about half the population to the unrequired and generally ineffective creams and lotions.

  459. Leo:

    …Although I can’t help being slightly alarmed by the fact that:

    Gore makes a film with some holes in that says “we’re doing the right thing by being worried” and gets an oscar.

    Durkin makes a film with some holes in that says “we’re not doing the right thing by being worried” and gets lynched.

    The fuss about TGGWS isn’t really about science is it?

    [Response: Gore did not fake any images, quote people out of context or generally say anything that the mainstream scientific community was not already saying. There is no equivalence. -gavin]

  460. Ken Winters:

    Re: 459 Gore’s movie was most certainly attacked. It was attacked in OpEd pieces, anti-AGW web-sites, Blogs, Talk radio, and even by members of the US Senate. His weight was criticized, his motives were questioned, etc., etc. The difference is that in this case, the scientific mistakes (intentional or otherwise) of Durkin’s movie are far too significant to ignore. If the truth is important, and it is, then Durkin’s movie needs to be taken to task for it’s numerous errors and misleadings.

  461. P. Lewis:

    The fuss about TGGWS isn’t really about science is it?

    In so far as it’s about the misrepresentation of science, for what seems like the gazillionth time on this thread alone, it is precisely about science.

    Scientists care (or should) about how their science is used and abused.

  462. Leo:

    Gavin,

    I understand that Durkin is flying in the face of the weight of scientific opinion. I understand also that his arguments don’t stand up. What I don’t understand is the vitriol that has been directed at him. It disturbs me.
    He’s said some things that are perhaps misguided, perhaps deliberately contentious. Regard him as a clown or a random nutter if you will. But to set him up as some kind of evil mastermind is taking things a bit far – and quite likely to turn him into a hero for the real nutcases.

  463. Leo:

    for what seems like the gazillionth time on this thread alone, it is precisely about science.

    Of course discussion in this thread is mostly about the science. I meant the main media furore/ blogfests which are linked to above.

  464. Nick Gotts:

    Re #462 “I understand that Durkin is flying in the face of the weight of scientific opinion. I understand also that his arguments don’t stand up. What I don’t understand is the vitriol that has been directed at him. It disturbs me.”
    There are at least three reasons for it:
    1) Durkin, explicitly in the title of his programme, is claiming that the vast majority of climate scientists are liars and frauds.
    2) As has been amply demonstrated here and elsewhere, he used deliberately distorted and misleading material – it’s not a question of honest mistakes.
    3) This is an extremely serious and urgent issue – it’s about people’s lives and the beauty and diversity of the natural world. Telling lies in order to convince people there’s no need to act is wicked. Compare with the “vitriol” directed (quite justifiably in my opinion) at those claiming HIV does not cause AIDS, or that vitamin supplements are better treatment for AIDS than ARVs.

  465. Barton Paul Levenson:

    [[I understand that Durkin is flying in the face of the weight of scientific opinion. I understand also that his arguments don’t stand up. What I don’t understand is the vitriol that has been directed at him. It disturbs me.
    He’s said some things that are perhaps misguided, perhaps deliberately contentious. ]]

    You seem to have missed the point that Durkin didn’t just show a controversial point of view. He lied about it. He distorted data. He altered charts. He quoted people out of context. That’s why people are enraged at him. There’s nothing morally wrong in being an AGW skeptic. But Durkin’s documentary was dishonest.

  466. Mike Donald:

    #464
    Very well put Nick.

    I’ve been attempting to become a member of C4 Forums basically to spread the word on RealClimate.org. After all we’re mainly talking to the converted here.

    http://community.channel4.com

    Regards all

    Mike

  467. Ray Ladbury:

    Re 462, 463, 464, etc.
    A dishonest man has always been villified, and Durkin has shown himself beyond all doubt to be dishonest. He has also thrown down the gauntlet to the scientific community–calling them “swindlers”. He distorted peoples’ positions. He distorted the science. Calling him a lying sack of organic matter is probably charitable.
    If the nutcases choose to glorify him, well it is their prerogative to glorify one of their own. I don’t think we can care what the nutjobs think. All we can do is try to expose them, isolate them and marginalize them. We do this by sticking to the high road in terms of our adherence to truth, but I don’t think it is reasonable to ignore a frontal assault on the integrity of science.

  468. Leo:

    #464, Nick

    OK, let’s be clear about this. It’s all political.

    The title of the programme is a piece of transparent posturing. I don’t believe that anyone tuning in could seriously believe this was going to be a thorough, evenly-weighted discussion of the facts. It is clearly an anti-establishment 2-fingered salute. It as good as says ‘this a political message’.

    Television is not science. Ever.

    Exactly how wrong Durkin is, and whether that wrongness is accidental or deliberate is in my view irrelevant. Being wrong is not a crime. Ideas are not crimes, although actions based on them may be. Durkin is not unilaterally changing policy on carbon emissions. He is not denying antiretrovirals to anyone.

    I would rather be uncomfortably warm for the rest of my short life than live in a world where people are afraid to be wrong. If we’re not wrong some of the time, we’re not trying hard enough. If we don’t allow people to be deliberately wrong some of the time, we’ll also deny others the chance to be right.

  469. Nick Gotts:

    Re #468 “If we don’t allow people to be deliberately wrong some of the time, we’ll also deny others the chance to be right.”

    OK Leo, let’s be clear about this: “being deliberately wrong” is a euphemism for lying. You are supporting Durkin’s right to lie. I never said this is or ought to be a crime; I said that with regard to this issue, as with regard to the closely parallel case of AIDS denialism, it is wicked. Many things which are wicked are not and ought not to be crimes.

    It’s not about whether you personally are going to be “uncomfortably warm”. It’s about the potential for millions of premature human deaths, and mass species extinctions.

    The claim I have quoted from you above is absurd: it simply does not follow that if we object to lies, this will obstruct the search for truth.

  470. Barton Paul Levenson:

    [[Being wrong is not a crime. Ideas are not crimes, although actions based on them may be. Durkin is not unilaterally changing policy on carbon emissions. He is not denying antiretrovirals to anyone.

    I would rather be uncomfortably warm for the rest of my short life than live in a world where people are afraid to be wrong. If we’re not wrong some of the time, we’re not trying hard enough. If we don’t allow people to be deliberately wrong some of the time, we’ll also deny others the chance to be right. ]]

    You seem to be missing the fundamental distinction between “being wrong” and “lying.” Until you get that sorted out, you won’t understand why people are mad at Durkin.

  471. David B. Benson:

    Re #469: Nick Gotts — Billions

  472. Julian Flood:

    [[ why can’t we assume that it hasn’t been kick-started by solar radiation or some other ‘forcing agent’ just as it has in the past?]]

    [Because we’ve measured the isotope ratios and know that the new CO2 in the air is almost all from burning fossil fuels.]

    I can think of three processees which would alter the isotope ratios of atmospheric carbon. Four if you count burning fossil fuel. ‘Because we can think of no other reason’ is not good enough in a vital subject like this.

    We ‘know’ that the excess carbon in the atmosphere is anthropogenic: is there any paper on the web which explains this certainty? I’ve searched myself, but what little I’ve found so far has been unconvincing.

    Thanks in advance.

    JF

    [Response: This is as ‘known’ as anything in earth science. 13C ratios, 14C ratios, O2 measurements, known emissions, carbon uptake by terrestrial biosphere and ocean are all consistent with this and no other explanation. This is a slightly out of date description http://www.radix.net/~bobg/faqs/scq.CO2rise.html (but it’s still valid) and this is good too: http://www.realclimate.org/index.php/archives/2004/12/how-do-we-know-that-recent-cosub2sub-increases-are-due-to-human-activities-updated/ Actually, this is a good test. If the data on this are unconvincing to you, then there is nothing that you will ever be convinced of. -gavin]

  473. Hank Roberts:

    Nominating the above response by Gavin as a FAQ worth linking high and wide.

  474. Dave Rado:

    Re. 454, Mike Donald – write to Ofcom. There’s a model letter to Ofcom here (where it says “Dear Ofcom”).

  475. Peter Geldard:

    As a total layman here, I watched the programme and then decided to look into the claims myself. Well – I guess I am a pretty average bloke and a living part of the “great unwashed” as us non academics have been referred to. To me the arguments put forward have some validity but probably not as much as the arguments that the current trend of temperature rising is caused by man. However, those in the know in this are really not helping themselves. There is simply too many unknowns to make statements which contain the amont of uncertainties of the IPCC reports. Where this leads to is “the end of the world is nigh” journalism and to be quite frank, the general public are sick to death of CO2 CO2 and more CO2. Our government policy makers view global warming as a cash cow to milk more taxes, we see local authorities wasting tax payers money employing a graduate on £50,000 as an “global warming environment officer” etc etc. In short the general public are quite frankly sick to death of having this whole thing rammed down our throats. There is also a lack of good quality information for people without a science degree and that is where this programme scored points – it was easy for a layman to understand – which is something the science community have failed to do. From my understanding water vapour is a bigger greenhouse gas than CO2 – should we reduce that also !!!!! To finish I certainly think that man is not helping the planet with our over reliance on fossil fuels, but lets not blame the worlds ills on CO2 For a layman it is hard to understand how a part of our atmosphere that is 0.03 -0.06 % is causing so many problems. I certainly believe that part of the warming we see is natural but probably being helped somewhat by mankind.

    [Response: Water is a feedback not a forcing, Calculating the greenhouse effect etc… The answers are out there… – gavin]

  476. Leo:

    #468.469.470.

    deliberately wrong

    uncomfortably warm

    I take those words back.

    From everything I have read, I don’t actually believe Durkin is lying. I think he believes what he says.

    I don’t think he’s right, but I think his conviction is genuine.

    That is why I defend his right to voice the opinion of a significant minority, however misguided I may think they are. Just as I would defend the right of stalinists, fascists, anarchists, scientologists, jihadis and teenagers to voice their opinions.

    Science works by consensus, not coercion. The consensus has not been changed by this film. Is that not enough?

    (‘Uncomfortably warm’ was facetious and deserved the contempt it received.)

  477. Isaac Held:

    Re #475:

    Dear Peter,

    We appreciate your desire to understand this problem more clearly. Let me address one specific point that you raise.

    You find it remarkable that CO2 is such a powerful warming agent and yet is such a small fraction of the atmosphere. You are not alone in finding this strange, and you are right to focus on this question at the start. Humanity is changing the amount of oxygen in the atmosphere too (we can even measure these changes) but these changes are tiny because there is so much oxygen. But we can and are changing the concentration of CO2 in the atmosphere profoundly. The main point to realize here is that most of the atmosphere — the nitrogen and oxygen molecules and the argon atom — do not interact significantly with radiation at all. After these three, water vapor and carbon dioxide are the next in line. If you can accept this fact (which has been very well established for over a century), then it might be less strange to you that carbon dioxide and water vapor are the big players in setting the temperature of the Earth.

    The reason why water vapor changes are thought of as a consequence of CO2 changes, and not a separate forcing agent, in discussions of climate change is a bit more involved. But first things first, and before tackling this issue, you first have to convince yourself that gases that make up a small fraction of the atmosphere can be the dominant greenhouse gases.

  478. Dave Rado:

    Re. 475

    Hi Peter

    As a total layman here, I watched the programme and then decided to look into the claims myself.

    From what you’ve written subsequently you seem to have been looking at disinformation sites with a policy agenda rather than scientific articles that egenuinely attempt to explain the science of climate in an honest way. If the articles on realclimate are too technical, try the ones on Wikipedia. Start here:
    http://en.wikipedia.org/wiki/Climate_change

    Our government policy makers view global warming as a cash cow to milk more taxes

    The following scientific bodies are all calling for much stronger action to reduce emissions than any government has considered so far:

    Academia Brasiliera de Ciências (Brazil)
    Royal Society of Canada
    Chinese Academy of Sciences
    Academié des Sciences (France)
    Deutsche Akademie der Naturforscher Leopoldina (Germany)
    Indian National Science Academy
    Accademia dei Lincei (Italy)
    Science Council of Japan
    Russian Academy of Sciences
    Royal Society (United Kingdom)
    National Academy of Sciences (United States of America)
    Australian Academy of Sciences
    Royal Flemish Academy of Belgium for Sciences and the Arts
    Caribbean Academy of Sciences
    Indonesian Academy of Sciences
    Royal Irish Academy
    Academy of Sciences Malaysia
    Academy Council of the Royal Society of New Zealand
    Royal Swedish Academy of Sciences
    NASA’s Goddard Institute of Space Studies (GISS)
    National Oceanic and Atmospheric Administration (NOAA)
    National Academy of Sciences (NAS)
    State of the Canadian Cryosphere (SOCC)
    Environmental Protection Agency (EPA)
    Royal Society of the United Kingdom (RS)
    American Geophysical Union (AGU)
    American Institute of Physics (AIP)
    National Center for Atmospheric Research (NCAR)
    American Meteorological Society (AMS)
    Canadian Meteorological and Oceanographic Society (CMOS)

    See here and here and here.

    Surely you don’t think these scientific bodies all want to milk you for your taxes?

    The CEOs of almost all of the Fortune 500 and Times Top 100 business are also calling for much stronger action to reduce emissions than any government has considered so far:
    : E.g. see here..

    Surely you don’t think the CEOs of almost every major corporation wants to milk you for your taxes?

    There is also a lack of good quality information for people without a science degree

    You’ve just looked in the wrong places. Try Wikipedia if you find this site too technical.

    and that is where this programme scored points

    Scoring points by lying is fraud.

    water vapour is a bigger greenhouse gas than CO2 – should we reduce that also !!!!!

    Water vapour levels can’t change unless the temperature changes. If you add a whole load of extra water vapour to the atmosphere it condenses again almost immediately. Climate change is caused by changes in the factors that influence the climate. Gavin’s link explains it in more detail. As does Wikipedia: http://en.wikipedia.org/wiki/Positive_feedback

    but lets not blame the worlds ills on CO2

    No climate scientist is blaming all of the world’s ills on CO2. What they are saying based on overwhelming evidence, is that if we don’t reduce emissions drastically and soon, there will be serious consequences.

    I certainly believe that part of the warming we see is natural but probably being helped somewhat by mankind.

    Most of the warming during the past 40 years is due to greenhouse gas emissions. Please read the linked articles before posting back.

  479. Dave Rado:

    Re. 476

    Making up data isn’t voicing an opinion. If making up data isn’t lying in your book then we must be using different dictionaries. And Durkin has form.

  480. James:

    Re #472: [We ‘know’ that the excess carbon in the atmosphere is anthropogenic: is there any paper on the web which explains this certainty?]

    There is an answer which is a lot simpler than isotope ratios and such, and to my mind a lot more convincing. There are various economic references where you can look up the amount of coal, oil, and natural gas that was mined/pumped every year back to the 19th century. From simple chemistry, you can figure out how much CO2 that produces, and a bit more simple math will tell you how that compares to the total CO2 in the atmosphere. Do the figures, and you will find a good match with the measured increase. (Actually the amount humans produce is rather larger, because some dissolves in the ocean.)

    So if you hope to invoke some non-human process to explain the measured CO2 increase, you not only have to tell us what it is, you have the problem of explaining what happened to all the CO2 that humans did produce. I would be very surprised indeed if you could come up with even a superficially-plausible explanation – at least one that doesn’t involve UFOs shipping it off to their home planet :-)

  481. Robert:

    476: Umm, Leo, Politics works by concensus, not science.

    Science works by logic and speculation; leading to hypothesis, experiment, and replication; leading to theory and logic.

    Concensus isn’t required, as Einstein said: “200 scientists think I’m wrong? It would only take 1 to prove it.”

    cheers,
    Robert

  482. Mark A. York:

    “200 scientists think I’m wrong? It would only take 1 to prove it.”

    That’s Crichton’s line. So name one who has a peer reviewed article that refutes AGW? I mean it only takes one. Got Milk?

  483. Leo:

    Robert #479

    Science works by logic and speculation; leading to hypothesis, experiment, and replication; leading to theory and logic.

    Concensus isn’t required, as Einstein said: “200 scientists think I’m wrong? It would only take 1 to prove it.”

    but if nobody accepts that proof as valid it’s meaningless. Durkin believes there is proof that global warming is mostly caused by the sun. The weight of opinion is against him.

    He will doubtless (and indeed should) continue looking for that proof until he either changes his mind or changes concensus.

    The proponents of AGW theory must continue looking for holes in it and shoring it up with further research – the doubters will continue to doubt models and feedback theories until more supporting evidence can be found in the real world.

    That is where the science lies. Not in gagging opponents – That’s politics.

  484. Ray Ladbury:

    Re 479: Robert, any real scientist knows you are wrong. Science must operate by consensus, precisely because any one scientist, no matter how brilliant, can be wrong.
    Consider two episodes from the history of science:
    In the 1600s, before there was a real global scietific community, Isaac Newton dominated English science. As a result, the English were obliged to adopt both his inferior notation for the calculus and his corpuscular theory of light. Both mistakes cost English science dearly, setting it back decades in both mathematics and optics relative to the Continent.
    Now, let’s talk about your hero, Einstein: the 200 scientists who opposed Einstein’s relativity were not a scientific consensus, but a vocal minority. Einstein prevailed because the evidence convinced the majority of scientists he was correct. Yet Einstein opposed quantum theory all his life–to his dying day. Here, HE was opposed to the scientific consensus based on the evidence available, and he did not prevail. Had he prevailed, he would have held physics back. Both incidents represent the value of scientific consensus. You should learn what that really means.

  485. Barton Paul Levenson:

    [[the general public are sick to death of CO2 CO2 and more CO2.]]

    I know just what you mean. During the Blitz, all we ever heard about was air raids, air raids, and more air raids. Like we didn’t have any other concerns.

  486. Barton Paul Levenson:

    [[That is why I defend his right to voice the opinion of a significant minority, however misguided I may think they are. ]]

    Straw man argument. No one is saying he should be suppressed. We’re saying he should quit lying. If he wants to honestly argue against AGW, let him. It’s dishonestly arguing that we’re annoyed about.

  487. Barton Paul Levenson:

    [[476: Umm, Leo, Politics works by concensus, not science.
    Science works by logic and speculation; leading to hypothesis, experiment, and replication; leading to theory and logic.
    Concensus isn’t required, as Einstein said: “200 scientists think I’m wrong? It would only take 1 to prove it.”]]

    Ideas make the scientific consensus because they’ve panned out. The scientific consensus is part of how science works nowadays, and it seems to be working fantastically well to anyone following it. What do you propose to replace it with?

  488. Julian Flood:

    Re: 472 response. Thank you, that’s excellent. I’ll go away and think about it. Incidentally, I can think of reasons why isotopic signatures would change without invoking the burning of fossil fuel — it’s a bit of the argument I find unconvincing because of the ‘post hoc ergo propter hoc’ nature of the point.

    Thanks again.

    JF

  489. Hank Roberts:

    >why isotopic signatures would change without invoking the burning of fossil fuel
    Many isotope signatures change over geologic time in many ways. Fossil carbon shows up in the PETM event for example.

    And you can imagine reasons like, if the sun had quit producing C14 in our atmosphere 200 years ago, that would explain the current excess of C12. But we’d have noticed a change like that for other reasons.

  490. Hank Roberts:

    In other science news, plate tectonics turns out to be wrong, Wrong, WRONG …. well, no. This is how science works:
    http://scienceblogs.com/highlyallochthonous/2007/03/rebellious_mantle_refuses_to_t.php

  491. Leo:

    #486 – BPL

    Straw man argument. No one is saying he should be suppressed. We’re saying he should quit lying.

    &#479 – Dave R

    As I said above, I don’t believe him to be lying. I believe he is genuine in his convictions.

    If you are going to call him a liar, you need proof that he is being disingenuous.

    There are comments above suggesting complaints to ofcom. This is surely about censure and future censorship. The fact that he ‘has form’ should be an indication that his work needs to be approached with care, nothing more. What journalist doesn’t colour their work with their own opinions? I think Durkin has consistently done this more openly than most.

    I still think he’s wrong. I still don’t think he’s evil or dangerous.

  492. Dave Rado:

    If you are going to call him a liar, you need proof that he is being disingenuous.

    I could give hundreds of examples, but one is enough to prove the point – see
    here
    .

    What he has done more than most is not air opinions but distort facts.

  493. Dave Rado:

    Also (re. #491), when I referred to Durkin’s “form” I was not referring to him colouring his work with his opinions. The Independent Television Commission (ITC, Ofcom’s predecessor) published the following ruling on Durkin’s “Against Nature” series of programmes:

    “Comparison of the unedited and edited interview transcripts confirmed that the editing of the interviews with these four contributors had indeed distorted or misrepresented their known views. It was also found that the production company had misled them, when it originally sought their involvement, as to the format, subject matter and purpose of the programmes. No mention had been made of the critical position the programmes intended to adopt, for example in correspondence.”

    With regard to the “distorting or misrepresentation” the ITC referred to, one of many such edits Durkin made was to edit out the word “not” in the following statement by one interviewee:

    “I do not believe that these problems are caused mainly by population growth.”

    So his form is for intentional distortion/misrepresentation of the truth. Opionions have nothing to do with it.

  494. Julian Flood:

    Re 489:

    Sorry, what do you mean by fossil carbon? Do you mean high weight isotope depleted carbon? If so, one wonders whether a low isotope signature is some feature of warming events — does it show in other events that we know about, or is it just a feature of sudden spikes like the PETM and the current one?

    The science gets more fascinating the more we learn.

    Thanks!

    JF (still working through the first two references…)

  495. Leo:

    Dave,

    #493

    My point is that those are comments made nearly a decade ago about a different programme. By all means be alarmed. By all means treat his current film with suspicion because of it. But you cannot use this as proof that he is lying now.

    #492

    This is speculation. It shows that there is an error, and attempts to explain the error. It does not prove the error was intentional.

    If you are to discredit Durkin’s portrayal of the science involved here (I presently believe this thread has already discredited the science – I’m not questioning that) you will have to be more rigorous than he has been. Not less.

  496. Dave Rado:

    Leo, so if I take a graph and change parts of the data in it so that it appears to back up the point I want to make, that’s an error? I don’t understand your definition of “error”.

  497. Mike Donald:

    #486 #491 #492
    Well lying is a state of mind so unless you can do a Vulcan mind probe on him you can’t be sure. But as the voiceover in TGGWS said
    Quote
    It is the story of the distortion of a whole area of science.
    Unquote. 3min50sec

    http://video.google.com/videoplay?docid=-4520665474899458831

    Thanks Durkin. I couldn’t put it better myself!

    Cheers

    Freud

  498. Chris Nankervis:

    I am interested by the satellite discrepancy of atmospheric temperature. The atmosphere over the entire longwave spectrum by a braodband calculation would give an identical emitting temperature. The Earth will always appear the same temperature from space. (1) Window regions of the spectrum will get hotter as the surface and atmosphere warm. (2) Greenhouse regions will become increasingly opaque as greenhouse gases increase shifting them upwards into the colder atmosphere. The net affect of (1) and (2) MUST be neutral, as the outgoing radiation will only be reduced if the planetary albedo increases (i.e. incoming shortwave flux is reduced). If this is not true then the Earth would be ‘out of balance’. Even a 0.1K discrepany would result in an Earth-Atmosphere system warming or cooling at a significant rate. The longwave spectrum must have undergone a broadening. Shortwave absorbed by the atmosphere and Earth’s surface must equate to the outgoing radiation at the top of the atmosphere precisely.
    Temperature retrieval of the upper atmosphere depends on the chemical profile. A Fixed pressure output, may produce discrepances due to the height of the atmosphere increasing by to order of 40 metres for a 1’C surface temperature rise. This may sound small, but calculations at a constant pressure level would reduce the temperature in the upper atmosphere by as much as 0.45K, as the lapse rate at the tropopause is near dry rate (-g/cp) = -9.81K/km. One must note that the tropical 100hPa level is far colder than the polar or midlatitude 100hPa temperature. Then we have the retrieval theory dilema where an initial input requirement is a temperature a-priori (or guess), in order to give a reliable temperature profile.
    Any of the above factors could have potentially caused a error in the satellite temperature retrieval.
    It is true that upper tropospheric temperatures should be increasing at a rate greater than that of the surface. If the atmosphere was saturated then the rate of warming would be 40% greater by a simple calculation using thermodynamics and a fixed relative humidity. This is due to process known as separation of saturated adiabats. If however, the upper troposphere underwent a drying this affect would be reduced, by dynmical changes. The distrubution of water vapour in the vertical is an essential component to the vertical temperature profile.

  499. Leo:

    Leo, so if I take a graph and change parts of the data in it so that it appears to back up the point I want to make, that’s an error? I don’t understand your definition of “error”.

    If he deliberately and knowingly manipulated the data to make it fit his argument when in reality it did not, then yes he is lying.

    But I don’t think we can say for certain that that is what happened.

  500. Hank Roberts:

    Climate change is wiggly, Leo.

    Durkin said he presented smoothed data — losing the wiggles in the real data.
    “‘The original NASA data was very wiggly-lined and we wanted the simplest line we could find,’ Mr Durkin said.”
    When people look at the real data, seeing the wiggles, they can tell that he was wrong.

    And you say “Oops, no foul?”

  501. Geoff Wexler:

    It is ironical that a frequent justification for C4’s programme is that the media has been giving too little space to opponents of GW theory. The opposite is the case. The media tend to give the headlines but not the theory. On the other hand the “anti-GW theory party” has been allowed time to go beneath the headlines and provide apparently technical arguments, graphs etc. and interviews with Lindzen attacking all the modeling work.

    In my view one of the worst features of Durkin’s programme was it’s censorship of the theory which it was trying to undermine. Just one example was the assertion (repeated more than once) that

    “ALL climate models ASSUME that CO2 is the main cause of GW.”

    This is worse than a lie because it censors all the work on the attribution problem which is designed to investigate this issue without assuming the answer. But the trouble is that (as far as I know) neither channel 4 nor BBC TV (or radio) have ever informed the public about this work. So Channel 4 and Durkin have attacked a theory which has never been described properly to the general public. No wonder that there are so many people writing in to various web sites claiming to have had their minds changed.

    BBC Radio 4 suffers from a similar problem. During the last few years it has run three versions of the “Moral Maze” on GW which were based on very poor provision of information.

    #265 You write
    “The climate scientist didn’t come across too well on the radio interview though, perhaps because he wanted to cover too much ground in so little time”

    I think that scientist was John Houghton who amongst many other things has written the excellent book “Global Warming”. He has also reputed to have done good work in educating some of the Christian Evangelists. I’m afraid that your assessment was right and that just illustrates the difficulty. He needed much more time and did not concentrate on the fraudulent nature of the C4 programme. It may have needed someone with the skills of a barrister with forensic skills rather than a nice scientist.

  502. Bill H:

    Leo,

    Re: 499

    You may be right. It may be that Durkin was not aware of the distortion in the graph in question when making the programme. For instance the distortion may have been carried out by the “scientific consultant” to the programme, and Durkin in innocence accepted it as the genuine article.

    However, the error was pointed out more or less immediately after the broadcast, and Durkin has had plenty of time to admit to the error. He has done nothing of the sort and has on the contrary continued in a series of media articles (plus obscene emails) to justify the full content of his programme. Do you not agree that in so doing he is now knowingly a party to the deception, whereas before the broadcast he may have been only an unwitting party thereto?

  503. Dave Rado:

    Leo, 499, I’m baffled that you don’t, but getting back to the point, those of us who are complaining to Ofcom are doing so solely because we consider the evidence to be overwhelming that he set out to systematically deceive the public, not with a few “errors” but with a few hundred intentional deceptions. Ofcom rules do not restrict the airing of opinions. So your accusing us of wishing to restrict free speech is fallacious. We wish to prevent public service broadcasters from setting out intentionally to deceive the public. If Ofcom don’t agree that Durkin and Channel 4 did that, then our complaints will go straight into their bin.

  504. Dave Rado:

    Re. 498, have you read this?

  505. Hank Roberts:

    > The earth will always appear the same temperature from space

    What do you mean by “temperature” — measured how? Averaged over some time span? Instantaneously? According to whom? What’s your source for this? I’m not sure what you mean.

    As a broad generalization, it doesn’t seem credible to me.
    Imagery suggests the brightness in the infrared can vary, for example

    http://csep10.phys.utk.edu/astr161/lect/earth/watervapor_goes8.gif

    And until the planet’s in thermal equilibrium again, with the stratosphere currently cooling, changes ought to show up in a variety of bands over time.

  506. Hank Roberts:

    >498
    Ah, light dawns; I should have read your home page before asking you to explain; much more there, far more than I’ve read yet; but just skimming the main page clarifies what you meant above:
    > Earth does not look hotter from space by a simple broad-spectrum calculation or
    > by the use of an infra-red thermometer.
    Lots there; say more about what you do? (Or where to go read up — delighted to study, your page has a lot of info)

  507. Leo:

    Dave,
    I understand totally that you believe Durkin to have deliberately misled his audience. What I fail to understand is what makes your conviction of this so strong.

    I don’t think you have the evidence to press such a serious charge.

    With the exception of the mistake on the temperature graph, to which he has owned up and indeed corrected, all of his ‘lies’ as you insist on calling them are genuine, precedented, ongoing, corroborated disputes with the orthodoxy.

    The most noticeable being the dispute over the Hockey Stick. The range of dispute over the validity of this graph is well documented.

    It seems to be unclear which dataset(s) Durkin used for his graph, so I’m not saying his data are any better. But we should be more certain of their inaccuracy before crying foul. Perhaps Durkin should have used this graph, which appears to show a levelling off of temperature in the last few years. (Actually I’d be grateful for any information about this graph (Brohan et al, 2006). Is it accepted?)

    Hank #500

    Durkin said he presented smoothed data — losing the wiggles in the real data.
    “‘The original NASA data was very wiggly-lined and we wanted the simplest line we could find,’ Mr Durkin said.”
    When people look at the real data, seeing the wiggles, they can tell that he was wrong.

    Almost all global temperature graphs I have seen are smoothed. Without smoothing you get a broad scatter, making it hard to pick out the difference between trends and anomalies. I understand this to be a valid approach.

    What are the ‘real data’ that show him to be wrong?

  508. bill h:

    Leo, re: item 507

    You asked: “What are the ‘real data’ that show (Durkin) to be wrong?”

    They’re given in a previous comment, but here they are again to save you the trouble of searching.

    http://img103.imageshack.us/img103/6634/sdodgygraphgm3.jpg

    You can see the data published by NASA, cited by Durkin as his source, superimposed on Durkin’s graph. Would you not agree that, if he has used a smoothing technique, it is, even to the layperson, obviously flawed?

    You mention that Durkin has “owned up” to a mistake concerning the graph, and corrected it. Do you have a reference to this. As far as I can tell from Durkin’s numerous post-broadcast pieces on the subject he has treated the world to unrelenting justification of every aspect of the programme.

    You say that with the exception of the graph in question (which actually provides the basis of a major plank of Durkin’s thesis: it’s not a minor consideration as you suggest):

    “With the exception of the mistake on the temperature graph, to which he has owned up and indeed corrected, all of his ‘lies’ as you insist on calling them are genuine, precedented, ongoing, corroborated disputes with the orthodoxy.”

    Would you include his claims about tropospheric cooling as a “genuine dispute”, and on what grounds? This happens to be another major strand of his polemic.

    Bill

  509. Leo:

    Thanks Bill I’ll have to go and look into this.

    The corrected graph (for the second Transmission) can be found here :http://s157.photobucket.com/albums/t63/izzy_bizzy_photo/?action=view¤t=temp-rerun.jpg (from comment #32’s link on this thread)

    I don’t have the software to hand to do the overlay with it so I’ve no idea how it matches.

  510. Bob Ward:

    Has the paper by Christy et al published in JGR on 16 March added anything to the discussion of surface vs tropospheric temperatures, which was one of the pillars of the argument put forward by the programme?

  511. Barton Paul Levenson:

    [[As I said above, I don’t believe him to be lying. I believe he is genuine in his convictions.
    If you are going to call him a liar, you need proof that he is being disingenuous.]]

    Have you not paid attention to the posts in this thread? He altered charts and quoted scientists out of context. For details, see above.

  512. Leo:

    #511 BPL

    I am trying very hard to absorb all the arguments being put forward in this thread. However I’m confounded by the fact that I’m trying to balance one set of rants (Durkin) against another (too much of what is written above is hyperbole: levelling sweeping accusations with no real backup) f’rinstance:

    He altered charts and quoted scientists out of context. For details, see above.

    He published one incorrect graph, which he claims to have corrected.
    He is accused of misquoting one scientist – Wunsch.

    I’m not saying this is excusable but please stop exaggerating everyone. This is supposed to be about science.

  513. Adrianne:

    I see that people are commenting more and more about the documentary and I am glad to see this. Especially because there was a big need of facts that contradict Gore’s documentary that stated that the global warming was man-made.

    Actually, I liked alot the part of the movie that showed how much other factors influence the climate, and the oceans are one of them. I think the oceans should have been first discussed instead of trying to blame energy consumption, flying, driving, etc. Of course, the pollution in the cities is important, but not as important as stated in Gore’s movie.

  514. Dan:

    re: 512. Yes, it is about science. Which is why it is disingenous why so many skeptics/deniers quote articles and information from non-peer reviewed, unscientific sources such as web postings, op-eds in newspapers, and science fiction writers. Or equally worse, think they as laymen know more than literally thousands of climate scientists and professionals across the world. And then they spread the disinformation as if it were fact.

  515. Barton Paul Levenson:

    Re #513 – it is largely man-made, in fact, so Gore was right.

  516. Dick Veldkamp:

    #513 (Adrianne)

    Why would there be ‘a big need to contradict Gore’s documentary” ? Gore happens to be right, he’s just presenting what all the experts in the field agree on – and what is supported by the evidence.

    There are of course many factors influencing climate, but man-made CO2 is the (most important) root cause of the change we see now. The oceans are just responding. And that CO2 is produced by flying, driving etc.

    Please do a bit of reading: http://gristmill.grist.org/skeptics

  517. Guy:

    A lot of discussion here has centred on the dodgy world temperature graph (which I agree was a central plank in Durkin’s arguments). As has already been linked here (http://scienceblogs.com/stoat/2007/03/more_tggws_fakery.php) it does seem that the genuine source of the graph has been found – it is accurate to the last wiggle, and it lies here http://www.oism.org/pproject/s33p36.htm (although the axis in the GCCS are labelled incorrectly). What is perhaps striking about this source is that it is the legendary Oregon Institute of Science and Medicine (info here http://www.sourcewatch.org/index.php?title=Oregon_Institute_of_Science_and_Medicine – it is well worth a full read), which is run from a sleepy farm.

    Durkin removed the libellous NASA reference from the graph on repeated transmissions and shifted the data on the X axis, but what stikes me with some force is that his famous “wiggly line” defence does not now stand. It is very hard to imagine that this graph was nothing more than a ripped off (and then further altered) graph from a discredited – and thoroughly unscientific – website.

    Personally I can see why, when his documentary opened with the dramatic “you are being told lies”, some posters here have become rather agitated.

  518. Geoff Wexler:

    re : 507 To Leo.
    You write:
    “I understand totally that you believe Durkin to have deliberately misled his audience. What I fail to understand is what makes your conviction of this so strong.”

    There are lots of answers on this page. Just consider one example of a Durkinism which I quoted in #501 and repeat here:

    “ALL climate models ASSUME that CO2 is the main cause of GW.”

    I called it censorship before. Are you suggesting that this remark was an example of innocent ignorance?
    He has set himself up as an expert on the subject, so I should imagine that he must have looked at the TAR at least once. If so then the above statement is a seriously misleading deception. If not then he had no right to write a TV programme attacking GW theory from a position of total ignorance of it. It is possible that he might get away from the blame by claiming that this was a recording of someone else speaking. But it was at the very core of the programme’s argument. It was all devoted to the attribution problem and the drift of it was that there was no reason for concluding that CO2 contributes to warming …. no reason at all, why? because he is suggesting to you that the reasons do not exist.
    Without such reasons his case is made.

  519. P. Lewis:

    OK, Leo

    I’ve no wish to descend into politics, but consider the following hypothetical scenario:

    A. Politician states they are telling the truth (oxymoron, I know) about some evidence that A. Dictator has a Nasty Weapon or Two and that this Nasty Weapon or Two can hit our bases on an inland sea island in ~20 min. That evidence, A. Politician states, is held sufficiently incontrovertible to warrant an invasion of A. Dictator’s country to rid the world of said A. Dictator and his Nasty Weapon or Two. After this invasion we find A. Dictator but no evidence of this Nasty Weapon or Two stockpile. What are we to make of A. Politician’s claims?

    Substitute Durkin for A. Politician and TGGWS for Nasty Weapon or Two, and what do you get?

    Honestly mistaken and badly advised? Or mendacity and cherry-picking half-truths? Hmmm … tough call.

    TGGWS, I think, was about as truthful as were Enron’s last few sets of published annual accounts, i.e. largely misdirection dressed up as fact.

    Scientific fraud (and that is what “swindle” implies) is a serious accusation to level at any individual scientist, let alone the massed ranks of the IPCC contributors. And serious accusations need to be backed up with concrete evidence that will stand scrutiny. Durkin is the swindler, and most of the negative comments made here, IMHO, are warranted.

  520. Roger from NYC:

    As an uncommitted outsider who only recently has had the opportunity to pay more than desultory attention to the global warming issue, I have a question. What is the error, if any, in the following: (3 statements whose truth is almost universally acknowledged; thereafter some conclusions which flow reasonably, perhaps ineluctably, from those 3 statements.)
    Statement 1: There is vast, probably irrefutable, theoretical and empirical support for the notion that man-made greenhouse gases must be playing some role in the undisputed rise of global temperatures but the magnitude of that role is difficult to quantify.
    Statement 2: In relatively recent historical times there have been two very significant and well-documented temperature oscillations, the medieval warming and the Little Ice Age, which produced temperature deviations that considerably exceeded any experienced in the past century, without any Milankovitch forcing or man-made greenhouse gases being responsible. While many causes have been proposed, from the laughably silly (indirect effects of bubonic plague episodes) to the highly imaginative though still plausible, none has yet emerged from the realm of the conjectural. So a non-man-made greenhouse gases Climate Changer of major, if not Day After Tomorrow, proportions remains out there–lurking, sinister and unidentified, in the darkness of our uncertainty, capable of freezing or frying us in the future as it most demonstrably has in the past.
    Statement 3: Global temperatures rose in the 20th century prior to 1940, followed by a cooling c.1940-1975, succeeded by a resumed warming, while carbon dioxide concentrations rose throughout the period, and steeply after c.1940.
    Tentative Conclusion A: Statement 3 suggests that if the sharply rising carbon dioxide was more than nullified by aerosols from 1940-1975, then it may be a factor of fairly modest impact.
    Tentative Conclusion B: Statement 2 indicates a Factor X (or a set of factors) has been operating to cause dramatic cooling and warming for much of the past millenium, and it could, in more measured form, be operating today. And, further, that even a much attenuated Factor X (say at 20% of its former strength) would significantly outweigh the undramatic effects of man-made greenhouse gases (Tentative Conclusion A) as a player in post-1900 global warming.
    Firm Conclusion C: Even if Tentative Conclusions A and B are assigned probabilities that reduce them to less-than-likely status, and even if we overall assess a Factor X causation of 20th century and present day global warming a lesser probability than human activity, is anyone seriously willing to assert that Anthropogenic Global Warming has relegated Factor X, in a Bayesian statistical competition of rival hypotheses, to the lowly status of a “p-value less than .05 null hypothesis” in classical statistics? Or in plain English, with Factor X a continuing mystery, can any rational person emphatically proclaim that human activity has been shown to be the true culprit with the high degree of certainty science has traditionally, and properly, demanded?

  521. Dave Rado:

    He published one incorrect graph, which he claims to have corrected.

    Where did you get the idea there was only one? Every graph he showed was incorrect. And the one he claimns to have corrected was not the one I gave you the link to, it was a different one.

  522. Mike Donald:

    #513
    Adrienne,
    I clicked on your link (if you’ll forgive the expression). Er I think the article headed “Man stopped global warming with naval war in winter 1939/40″ doesn’t tell us the full picture. But anyone who accesses RealClimate is one up on the rest so good on you. I find the archives a mine of info.

    Regards

    Mike

  523. Leo:

    Dave #521, I don’t understand.

    This: http://img485.imageshack.us/img485/6576/temprerunhr7.jpg

    Is the correction of this: http://i157.photobucket.com/albums/t63/izzy_bizzy_photo/capture.jpg

    No?

    Your earlier link here: http://scienceblogs.com/stoat/2007/03/more_tggws_fakery.php
    appears to confirm (or at least doesn’t deny) that this correction is valid.

    Every graph he showed was incorrect

    I don’t have time just now, but I will review this thread in due course (probably not for a couple of weeks now as it’s quite substantial, and quite clogged with rhetoric and side-topics) and look again for the evidence that shows how each of these graphs is wrong. It would help me greatly if you can point me to comment #s that are relevant. If you are right I will certainly owe you an apology.

    [Response:The “corrected” graph merely removes the gross errors. It still fails to show the recent warming period – ie the data has been arbitrarily truncated – and it still uses a dubious datasource for the graph – William]

    Guy #517
    http://www.sourcewatch.org/index.php?title=Oregon_Institute_of_Science_and_Medicine

    thanks, I’ll look at that. Although:

    which is run from a sleepy farm.

    So what?

    P Lewis #519
    I get your point exactly. But the problem with your example is it can be used either way round.

    It’s an unfortunate truth that this topic is intimately bound up with Politics and even more with politics – having such grave implications. I don’t think you should apologise for veering into politics, capitalised or not. We just need to remain clear about which comments are political and which scientific.

    All:
    I’m going to have to put this down for a few days, but very much want to continue this discussion later. Thanks for your patience.

    Leo

  524. Barton Paul Levenson:

    [[Statement 2: In relatively recent historical times there have been two very significant and well-documented temperature oscillations, the medieval warming and the Little Ice Age, which produced temperature deviations that considerably exceeded any experienced in the past century, without any Milankovitch forcing or man-made greenhouse gases being responsible. ]]

    Statement 2 is flat-out wrong. The medieval warm period and the little ice age were NOT greater temperature variations than today. Sixteen studies, starting with the much-vilified but many times reproduced Mann et al. “hockey stick”, have shown that the world is warmer now than in the past 1000 years.

  525. Hank Roberts:

    Someone’s back again in 513, once again linking to that series of blogs flogging the claim that it’s not fossil fuel, it’s World War II’s oil spills that changed climate.

    I doubt it. I looked into it, and the oil from all the shipping lost in the war was roughly comparable to annual natural seepage of hydrocarbons. Google will find the info if you’re curious to look it up.

  526. Nick Gotts:

    re #476 “From everything I have read, I don’t actually believe Durkin is lying. I think he believes what he says.”
    That may not actually be exclusive possibilities. I would guess Durkin does believe that AGW is not happening, and that the scientists who say it is are part of an evil conspiracy against human progress; and so strong is he in that conviction, he feels justified in lying (distorting evidence and the views of others) in its service.

  527. Craig Mackenzie:

    Channel 4 Unrepentent

    I made a formal complaint to Channel 4 after watching TGGWS. Today they responded (see below). They appear not to be prepared to accept that they have done anything wrong.

    —-
    Dear Viewer

    “The Great Global Warming Swindle” is an opinionated, authored documentary from film-maker Martin Durkin which examines the scientific evidence that CO2 produced by human activity may not be the driver of climate change. It does not deny that Global Warming is taking place, but disputes whether humans are the cause. It argues that on the causes of Global Warming, the time for debate is NOT over, and that the science of Global Warming is far from settled.

    Channel 4 strongly defends its right to commission and broadcast this programme. It transmitted as part of a season of polemical films about climate change, which include two pieces broadcast recently: Theologian Mark Dowd’s film “God is Green” about the role that organised religion should be playing in reducing carbon emissions, and a film by the environmentalist George Monbiot called “Greenwash”, critically evaluating the claims of businesses that they are becoming environmentally friendly.

    “The Great Global Warming Swindle” is an important part of this season of films. It provides a powerful counterpart to Al Gore’s ‘An Inconvenient Truth’ and makes a valid and important contribution to the present debate.

    Please be assured however, that your complaint has been noted and logged. The log is distributed throughout Channel 4.

    Regards
    Tim Stone

  528. Hank Roberts:

    Roger

    You’re using logic based on assumptions or being fooled by the PR sites. It’s never wise to make conclusions without checking your facts; that’s leading you toward conclusions you may find attractive. This is always a risk.

    — The ‘Medieval Warm Period’ was just that — the Medieval period was western European, so was the warming. You can look this up.

    — Sulfate aerosols and CO2 and warming, you can look this up too.
    Half the fossil fuels burned were burned by about 1970; the other half of fossil fuels burned to date were burned since 1970.

    Aerosols act fast, but fall out fairly quickly. CO2 merely changes the planet’s ability to hold heat slightly, but act for a very long time.

    The aerosols from the early period were causing cooling, on a background of relatively little fossil fuel use, at a time the warming was just beginning (in retrospect) to show up.

    The aerosols after 1970 were cut back by the US Clean Air laws, while fossil fuel rate of use went up very fast.

    Now we’re seeing aerosols from dirty coal use in China and India, but it’s on not the natural background but the increasing temp background.

  529. John Gribbin:

    Re 96: I know I’m late on this – missed it before – but here is a classic example of the Big Lie. “Even Einstein held faith in his special theory in face of growing evidence.” Huh? There has never been any evidence against the special theory, which was devised in order to explain existing observations! Dragging Einstein’s name in gratuitously is one of the sure signs of someone without a case — like “they said Galileo was wrong.”

  530. Ernie Savage:

    It seems to me that this debate, and indeed others, not necessarily about issues in natural science, is bedevilled by a tendency among some journalists to seek a single prime cause. The environment is not like that; whatever global climatic changes may be being considered, both those taking place at the present time and those in the past, the causation is multifactoral. This may be driven by the medias `bosses`; certainly I hope that such an approach is driven by scientists.
    Over forty years teaching Geography, I tried to show my students this approach to the environment. Perhasp I, and many of my fellow teachers, have failed.

  531. Ray Ladbury:

    It amazes me that there seem to those who still question whether we have cause to doubt the bona fides of Mr. Durkin.

    I submit:
    Exhibit A: The title of his “work” is “The Great Global Warming Swindle”. This represents at least calumny if not outrigt libel against thousands of scientists who have dedicated their lives to understanding Earth’s climate.

    Exhibit B: The tone of the work is no less confrontational than the title. It is an anti-science diatribe that would have been cause for concern had it not been handles in such a ham-handed fashion.

    Exhibit C: The misrepresentation of data in a fashion that understates the significance of the changes being seen.

    Exhibit D: The misrepresentation of the position and words of Dr. Wunsch–again in a way that downplays the level of certainty in anthropogenic climate change and its effects.

    Then there are the previous works by the same director–all of which were anti-science in tone.

    The only defenseI heard the accused offer consisted of telling his accusers to attempt an anatomical impossibility.

    I don’t see much cause for lenient judgement.

  532. Mike Donald:

    #527
    Craig. Now off to Ofcom old bean. Click on the link in comment #22 and of course comment #51 and others…

    Come to think of it I noticed two things in Channel 4’s reply that could become part of your complaint to Ofcom. That’s nice of them.

    ” documentary from film-maker Martin D***** “.
    The Cambridge dictionary defines “documentary” as “a film or television or radio programme that gives facts and information about a subject”. Plenty of comments here indicate that Ofcom should teach Channel 4 the meaning of the word “documentary”.

    “It .. makes a valid and important contribution to the present debate.”
    The Cambridge dictionary defines the word “valid” as “based on truth or reason; able to be accepted:”

    Channel 4, Durking and those darn words “facts” and “truth”.

    Regards

    Mike

  533. Geoff Wexler:

    Re # 527 : Tim Stone from Channel 4 has correctly defined the subject of Durkin’s programme as concerned with the cause (attribution) of global warming but his “strong defence” of the programme concludes triumphantly with the bluster:

    “makes a valid and important contribution to the present debate.”

    I wonder which parts of the programme Tim Stone thinks are
    (a) valid ,
    (b) important,
    (c) a contribution………?

    the ice core diversion? the accusations of unspecified lies by Nigel Calder, the repeat of the ice age scare myth by Calder who helped to spread the scare a generation ago, the distortion of Wunsch’s interviews, the false suggestion that it is always assumed that CO2 is the main cause of GW, the doctoring of the sunspot evidence, the distortion of the temperature data, the confusion of SO2 from volcanoes with CO2, the assertion that the anthropogenic additions to CO2 are very small, the suggestion that environmentalists want to prevent Africa from slightly increasing its minute carbon footprint?

    Elsehwere Stone asserts that this film “examines the scientific evidence..”

    Remarkably Channel 4 has not offered a second opinion on this examination i.e they have attacked consensus science without explaining what they have been attacking. Monbiot’s film was about a completely different topic and does not offer any kind of balance. His article in the Guardian would have been rather more relevant.

    (I’m sorry of this partially duplicates other people’comments but I wanted it all in one place)

  534. Andrew:

    Dumb question, if there is an 800 year lag and feedback loop, don’t we have to wait 700 years to see the man-made CO2 effects of the past 100 years?

  535. Marion Delgado:

    Andrew:

    The global warming deniers are claiming temperature ALWAYS LEADS, not FOLLOWS C02, so in their terms, it’s the amount of increased C02 in the atmosphere we’d have to wait 800 years to see, due to global warming now. Clear?

    Also, I would call it a surprising question. That “800-year lag” is only for that cherry-picked slice of the ice-core records, so you must have gotten it there, and yet you literally drew the opposite interpretation from what the graph very clearly showed.

    Also: No. Temperature increases due to the physical action of adding additional amounts of a greenhouse gas, including C02, do not show an 800-year lag.

  536. James:

    Re #534: [if there is an 800 year lag and feedback loop, don’t we have to wait 700 years to see the man-made CO2 effects of the past 100 years?]

    No, because the speeds are different. The CO2 involved in the 800 year lag is mostly dissolved in the oceans. It takes centuries for the deeper parts of the ocean to warm up (or cool down) in response to a temperature change at the surface. The CO2 from burning fossil fuel goes directly into the atmosphere, and starts working right away.

  537. Adam:

    Posting this here for completeness. George Monbiot has posted his correspondence with the C4 commissioning editor after taking umbrage about his policy programme being lumped in with Durkin’s mockumentary. I didn’t see Monbiot’s programme, so can’t comment on that, but if it was vaguely accurate it’d be pretty justified umbrage.

    Anyway:

    http://www.monbiot.com/archives/2007/04/01/correspondence-with-hamish-mykura/#more-1052

  538. SomeBeans:

    Not surprised Monbiot is a bit peeved, following this episode I’m reluctant to believe any “science” that C4 broadcasts.

  539. Mike Donald:

    Hi chaps,
    And here’s Mr Durkin yakkin away on cjob (yes my thoughts exactly).

    http://www.cjob.com/shows/adler.aspx?mc=67455

    The last word by Durkin? I hope there’s another posting on this thread.

  540. SomeBeans:

    I wonder if they checked the rest of their facts as well as they checked the channel on which it was originally broadcast…

    (For the non-UK viewers BBC Channel 4 makes as much sense Pepsi Coca)

  541. Dwight Jones:

    Comment 77 by Hopp is completely apropos, the evidence presented re: the sun was worthy of consideration at all times.

    Further, if we are to characterize our climate as becoming wilder and more unpredictable, it follows that present-day deserts my turn green. Desertification may stall or contract. This possible cooling effect warrants some inclusion in these debates.

    Dwight

  542. David Klinke:

    Did anybody notice that early on in the *documentary* they went out of their way to say that environmentalists and global warming theorists have made this into a kind of religion? And, at least one of their *experts* (I didn’t watch the whole show – might have been more) gave his rationale/interview against (human generated) global warming inside a church/cathedral. To me, this was about as subtle as a sledge hammer. They were clearly playing into the fears of the religious right, suggesting that this is a threat to Christianity. This kind of manipulation works well with people who place faith above reason.

  543. Ray Ladbury:

    Re 541: Yes, and I may win the lottery tomorrow. However, it is prudent to save for my retirement assuming that I won’t. In a world where entropy must rise, optimists are wrong more often than not. That’s why they make lousy engineers.

  544. Adrianne:

    RE #522; Mike, The article “Man stopped global warming with naval war in winter 1939/40″ as a principle factor of climate, as explained (see: the oceans ), is certainly not the full picture. The story started when WWI had just ended, in winter 1918/19. By more than 10 degrees Fahrenheit the temperature increased at Spitsbergen over a few years time, and ended when WWII started. And what do we hear about the reasons today? Only this:
    It is natural fluctuations internal to the climate system; (Ola M. Johannessen, et.al, Tellus 56A (2004). Natural variability is the most likely cause (Lennart Bengtsson et.al, Journal of Climate, October 2004);. The 1930s warm period did not coincide with a positive phase of the NAO (North Atlantic Oscillation) (I.V.Polyakov, et.al.;, Journal of Climate, 2004).

    Also the latest IPCCâ??s Summary for Policymakers (Feb.2007) paid little attention to this event, only summarising the â??arctic warmingâ?? as follows:
    Average Arctic temperatures increased at almost twice the global average rate in the past 100 years. Arctic temperatures have high decadal variability, and a warm period was also observed from 1925 to 1945.

    This is as explanation hardly acceptable after such a long time. The warming at Spitsbergen is one of the major keys to understand climate changes during the last century, which was first observed and published by the Norwegian scientist B.J. Birkeland in 1930. As explained in detail in a number of interesting workouts, for example at http://www.seaclimate.com , the warming at Spitsbergen and subsequently the Arctic was generated by the seas around Spitsbergen; and the sea around England , subject to devastating fighting during WWI, are directly connected by the Norwegian Current, moving the water to the high North in a few weeks time. But to link these events together will presumably only understood, when IPCC would be required to define Climate (a shameful deficit of the FCCC not to have one). The source I use for my contribution says: Climate is the continuation of oceans by other means. I am sure, if climate would be understood in this way, many open questions could be answered more precisely.

  545. Adrianne:

    RE #516: Please note! The warming at Spitsbergen (and Arctic) occurred during the winter months!! The warming occurred since winter 1918/19!! What could CO2 contribute??

  546. Ray Ladbury:

    Adrianne, among the predictions of climate change: Warmer winters, shorter times between first and last frost and warmer overnight low temperatures (all on average, of course). Can you see that these might play a role overall? Of course, no single instance is evidence of GLOBAL climate change, but the coincidence of so many changes in the same direction from pole to pole are indeed strong evidence.

  547. Adrianne:

    RE #522; Mike, The article “Man stopped global warming with naval war in winter 1939/40″ as a principle factor of climate, as explained (see: http://www.seaclimate.de), is certainly not the full picture. The story started when WWI had just ended, in winter 1918/19. By more than 10 degrees Fahrenheit the temperature increased at Spitsbergen over a few years time, and ended when WWII started. And what do we hear about the reasons today? Only this:
    It is natural fluctuations internal to the climate system; (Ola M. Johannessen, et.al, Tellus 56A (2004). Natural variability is the most likely cause (Lennart Bengtsson et.al, Journal of Climate, October 2004);. The 1930s warm period did not coincide with a positive phase of the NAO (North Atlantic Oscillation) (I.V.Polyakov, et.al.;, Journal of Climate, 2004).

    Also the latest IPCCâ??s Summary for Policymakers (Feb.2007) paid little attention to this event, only summarising the â??arctic warmingâ?? as follows:
    Average Arctic temperatures increased at almost twice the global average rate in the past 100 years. Arctic temperatures have high decadal variability, and a warm period was also observed from 1925 to 1945.

    This is as explanation hardly acceptable after such a long time. The warming at Spitsbergen is one of the major keys to understand climate changes during the last century, which was first observed and published by the Norwegian scientist B.J. Birkeland in 1930. As explained in detail in a number of interesting workouts, for example at http://www.seaclimate.com , the warming at Spitsbergen and subsequently the Arctic was generated by the seas around Spitsbergen; and the sea around England , subject to devastating fighting during WWI, are directly connected by the Norwegian Current, moving the water to the high North in a few weeks time. But to link these events together will presumably only understood, when IPCC would be required to define Climate (a shameful deficit of the FCCC not to have one). The source I use for my contribution says: Climate is the continuation of oceans by other means. I am sure, if climate would be understood in this way, many open questions could be answered more precisely.

  548. Hank Roberts:

    The people Adrienne represents — arguing based on their own unique definition of the word “climate” — keep popping in here posting links to their many websites.

    I wish they’d do the math. Sure there’s a correlation between arm-waving numbers and temperatures, or no way to disprove it, without having some actual numbers.

    There’s a correlation between sunspots and wars, and there’s a correlation between wars and global warming, and there’s a correlation between sunspots, suicides, and heart attacks, and so on.

    Given enough numbers, correlations are inevitable. You can look this stuff up if you don’t believe it. Heck, make up some likely correlation and try it in Google Scholar — someone’s likely already published it.

    I did a little homework-help searching before and gave them the links to estimates of the amount of natural seepage of hydrocarbons.

    Here’s one again, as a starting point:

    http://www.springerlink.com/content/bya6g7r7ceebanrl/

    “….The amount of natural crude-oil seepage is currently estimated to be 600,000 metric tons per year, with a range of uncertainty of 200,000 to 2,000,000 metric tons per year. Thus, natural oil seeps may be the single most important source of oil that enters the ocean, exceeding each of the various sources of crude oil that enters the ocean through its exploitation by humankind.”

    If they want to argue that oil pollution from wars causes climate change, they ought to try collecting some verifiable numbers, with the cites to the sources — not just repeatedly posting links to their pages to get their Google rank up.
    And not just numbers that agree with the argument—-all the available information. Put it up in public where someone who can do statistical analysis has access to it.

    Not that such a collection is a good enough basis —- because you really have to talk to a statistician _before_ you start collecting data, if you want to be able to do an analysis that’s useful.

  549. Adrianne:

    RE #546 Ray Ladbury, thanks that you put the finger on the problem of current discussion. Birkeland stressed already in 1930 that the sudden rise of winter temperature at Spitsbergen could: probably be the greatest yet known rise on earth. Recently Lennart Bengtsson et.al, JoC 2004, acknowledged that this event is: one of the most puzzling climate anomalies of the 20th century. A graph showing the rise can be found on http://www.oceanclimate.de .
    Is it really that puzzling? The point is that during winter at Spitsbergen at latitude 80 degrees North, just 1000km away from the North Pole, the influence of the sun can be neglected for several months. At that time, around winter 1918/19 not one single natural event has been observed. No earthquake, tsunami, volcano, or meteorite, which could have triggered this event. What can be said for sure, that only the seas around Spitsbergen could have initiated and sustained this winter warming over two decades until it ended in winter 1939/40. One need only to accept the fact that the Norwegian/Greenland Sea must have playing the major role in this event, thereon it should be possible to identify the cause. It would be late, but not to late!

  550. Hank Roberts:

    Adrienne’s site refers to Bengtsson, (the page uses an image from it, but gives no link).
    Their claim is that “not one single natural event has been observed” — suggesting that Bengtsson’s paper supports their claim that the warming described is inexplicable — then the page offers the World War I timing as an explanation.

    Check the sources for claims like this, to assess whether you’re getting science or not.
    When websites make claims but don’t provide links to sources, Google Scholar will find them if they’re real.

    Compare what Bengtsson actually wrote: http://edoc.mpg.de/175055

    “… we suggest that natural variability is the most likely cause with reduced sea ice cover being crucial for the warming. A robust sea ice-air temperature relationship was demonstrated by a set of four simulations …. the observed early century surface air temperature anomaly revealed that it was associated with similar sea ice variations. …. the simulated temperature increase in the Arctic was caused by enhanced wind driven oceanic inflow into the Barents Sea with an associated sea ice retreat.

    “The magnitude of the inflow is linked to the strength of westerlies into the Barents Sea.”

  551. Russ Willis:

    “the 40-70 cooling type period is readily explained, in that the GCMs are quite happy to reproduce it, as largely caused by sulphate aerosols” – this is a v. bold statement – just because something can be modelled does not mean that it is correct – it might be, but not necessarily. It’s very easy to be convinced by modelling, probably because it’s relatively easy to model even extremely complex patterns, after the event – however such models usually break down when asked to predict events. Just take the weather, protein structures or even the stock market as examples – people have being attempting to model these processes for years with relativey little progress.

    “but if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its so small” – I’m sorry, but the lag is either there or it isn’t – you cannot pretend it isn’t there just by squashing up the time axis. I hope you didn’t really mean this – maybe you could try plotting your graph on bigger piece of paper, perhaps!

    “The correct interpretation of this is well known: that there is a T-CO2 feedback” – “correct interpretation” – this is a subjective statement (and probably an oxymoron) – please give us the facts, your opinions or both, but not your opinions dressed up as facts.

    I am still open minded on the GW issue and am hoping to be persuaded by convincing evidence. However, I find that its very difficult to get a clear picture of the situation, from either side, because the data are so clouded by interpretation and subjectivity

  552. Barton Paul Levenson:

    Adrianne —

    I think the people who came up with the oil-slick theory of climate change may yet rank with the most brilliant scientists of our time. I mean men like Velikovsky, Von Daniken, John Mack, and Henry Morris. Men with vision, who strike out boldly into new territory without worrying about what so-called mainstream scientists think.

  553. Hank Roberts:

    Russ:
    http://www.copernicus.org/EGU/cp/cpd/3/435/cpd-3-435.htm
    Hat tip to: http://scienceblogs.com/stoat/2007/03/yet_more_tco2_lags.php#more

  554. John Mashey:

    on oil-slicks: (slightly whimsical)

    I’d observe that the cooling effects of sulfate aerosols are well-known, are relatively, can go up very quickly (as from a major volcanic eruption), but come down fairly quickly unless somebody keeps generating the aerosols.

    Ascribing quick cooling directly to war and oil-slicks seems a *real* reach, given normal oceanic temperature inertia (not thermohaline circulation events).

    Ascribing *some* of the 20th-century NH temperature jigglinh to fast, dirty industrialization periods around WW I and WW II/Cold War doesn’t seem quite so-far-fetched…
    in which case, the oil-slick theory would be a typical confounding of correlation & causation. I.e., there may be cooling from periods of intense sulfate production happening due to all-out industrial production, which has certainly occurred during major wars.

    I looked for one simple chart that showed world coal and steel production since 1900, but couldn’t find a nice one in any one place, so:

    http://www.data360.org/dsg.aspx?Data_Set_Group_Id=813 for US, see yellow line

    http://capita.wustl.edu/capita/CapitaReports/EmisTrends/sox2.gif coal production: note peaks around WW I and WWII, and dip during Great Depression.

    Anyway, the causal chain:
    industrial activity (esp steel in Germany, UK, US) -> sulphate gyrations -> fast localized cooling/warming

    seems at least plausible. The sulfate chart on p157 of Ruddiman’s book is useful.

  555. David B. Benson:

    Re #551: Russ Willis — When the ocean warms, more of the disolved carbon dioxide goes into the air. This process requires several centuries to be noticable in the ice core records. But also it has been well known for over a century now that carbon dioxide in the air is a greenhouse gas, heating the air and surface.

    What has happened for the past 250 years, but most noticably in the past 50, is that fossil carbon has been artifically (that is, by humans) converted into carbon dioxide in the atmosphere. Therefore the climate is now out of balance and is warming.

    On a sidebar there is a link to the AIP history of climatology site. You will find this to be a good read…

  556. Russ Willis:

    Dear All
    I’m sure these data are well known, but I can’t find them and I’d be very grateful if someone could help:

    Can anyone tell me what proportion of “man made” CO2 is due to processes that we can do little about (in the short term anyway), such as human and animal respiration (inc. livestock farming)? Is there a breakdown of the sources of CO2 production somewhere – it would certainly be very useful? In other words is the exponential increase in the human global population, which has ~doubled since 1960, a problem or not?

    [Response: Try http://www.ghgonline.org – gavin]

  557. Marcus:

    Russ Willis: You have to think about the carbon cycle when looking at sources such as animal respiration: remember that every atom of carbon emitted in CO2 in breath was once an atom of carbon that a plant took out of the atmosphere. Therefore, the net effect of respiration on CO2 is effectively zero. The sources of CO2 can really be divided up into: fossil fuel emissions (the largest portion), cement production emissions (fairly small), and deforestation/land use change emissions (medium size, but uncertain, and possibly offset by forest regrowth)

    Now, methane is an entirely different story. There livestock and rice paddies are quite important.

    (The exponential increase in human population is still a problem because that increases the total energy demand, but it isn’t because of our breath)

  558. Nick Gotts:

    Re #556, 557. Human population is not growing exponentially. In percentage terms, according to Wikipedia the peak growth rate was reached in 1963 at 2.19% per annum (before that, growth had for a long time been superexponential i.e. the percentage increase per year was itself increasing); it has since fallen fairly smoothly to 1.14%. In terms of absolute rate of increase – the arithmetic excess of births over deaths over a given period – the peak was probably reached around 2000, and since then the increase has been sublinear. None of this means population growth is not a problem, but it’s one we have a good handle on. Urbanisation, increasing living standards, improved status and education for women, and better availability of contraception and abortion all appear to contribute to lowering birth rates; and urbanisation, which we couldn’t stop even if we wanted to, is probably the main driver, particularly as it contributes to improved status and education for women, and availability of contraception and abortion.