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Convenient Untruths

Filed under: — group @ 15 October 2007 - (Svenska) (Español)

Gavin Schmidt and Michael Mann

Update 10/18/07: We are very disappointed that the Washington Post has declined to run an op-ed placing the alleged 9 ‘errors’ in a proper scientific context, despite having run an extremely misleading news article last week entitled “UK Judge Rules Gore’s Climate Film Has 9 Errors”.

Last week, a UK High Court judge rejected a call to restrict the showing of Al Gore’s An Inconvenient Truth (AIT) in British schools. The judge, Justice Burton found that “Al Gore’s presentation of the causes and likely effects of climate change in the film was broadly accurate” (which accords with our original assessment). There has been a lot of comment and controversy over this decision because of the judges commentary on 9 alleged “errors” (note the quotation marks!) in the movie’s description of the science. The judge referred to these as ‘errors’ in quotations precisely to emphasize that, while these were points that could be contested, it was not clear that they were actually errors (see Deltoid for more on that).

There are a number of points to be brought out here. First of all, “An Inconvenient Truth” was a movie and people expecting the same depth from a movie as from a scientific paper are setting an impossible standard. Secondly, the judge’s characterisation of the 9 points is substantially flawed. He appears to have put words in Gore’s mouth that would indeed have been wrong had they been said (but they weren’t). Finally, the judge was really ruling on how “Guidance Notes” for teachers should be provided to allow for more in depth discussion of these points in the classroom. This is something we wholehearted support – AIT is probably best used as a jumping off point for informed discussion, but it is not the final word. Indeed, the fourth IPCC report has come out in the meantime, and that has much more up-to-date and comprehensive discussions on all these points.

A number of discussions of the 9 points have already been posted (particularly at New Scientist and Michael Tobis’s wiki), and it is clear that the purported ‘errors’ are nothing of the sort. The (unofficial) transcript of the movie should be referred to if you have any doubts about this. It is however unsurprising that the usual climate change contrarians and critics would want to exploit this confusion for perhaps non-scientific reasons.

In the spirit of pushing forward the discussion, we have a brief set of guidance notes of our own for each of the 9 issues raised. These are not complete, and if additional pointers are noted in the comments, we’ll add them in here as we go along.

  • Ice-sheet driven sea level rise Gore correctly asserted that melting of Greenland or the West Antarctic ice sheet would raise sea levels 20ft (6 meters). In the movie, no timescale for that was specified, but lest you think that the 20 ft number is simply plucked out of thin air, you should note that this is about how much higher sea level was around 125,000 years ago during the last inter-glacial period. Then, global temperatures were only a degree or two warmer than today – and given that this is close to the minimum temperature rise we can expect in the future, that 20 ft is particularly relevant. The rate at which this is likely to happen is however highly uncertain as we have discussed previously.
  • Pacific island nations needing to evacuate Much of Tuvalu is only a few feet above sea level, and any sea level rise is going to impact them strongly. The impacts are felt in seemingly disconnected ways – increasing brine in groundwater, increasing damage and coastal erosion from tides and storm surges, but they are no less real for that. The government of Tuvalu has asked New Zealand to be ready to evacuate islanders if needed, and while currently only 75 people per year can potentially be resettled, this could change if the situation worsened.
    In the movie there is only one line that referred to this: “That’s why the citizens of these pacific nations have all had to evacuate to New Zealand”, which is out of context in the passage it’s in, but could be said to only be a little ahead of it’s time.
  • Climate impacts on the ocean conveyor The movie references the Younger Dryas event that occurred 11,000 years ago when, it is thought, a large discharge of fresh water into the North Atlantic disrupted the currents, causing significant regional cooling. That exact scenario can’t happen again, but similar processes are likely to occur. The primary unresolved scientific issue regards how quickly the circulation is likely to change as we move forward. The model simulations in the latest IPCC report show a slowdown in the circulation – by about 30% by 2100 – but there is much we don’t understand about modeling that circulation and future inputs of freshwater from the ice sheets, so few are willing to completely rule out the possibility of a more substantial change in the future. Further discussion on what this really means and doesn’t mean is available here and here.
  • CO2 and Temperature connections in the ice core record Gore stated that the greenhouse gas levels and temperature changes over ice age signals had a complex relationship but that they ‘fit’. Again, both of these statements are true. The complexity though is actually quite fascinating and warrants being further discussed by those interested in how the carbon cycle will react in the future. We’ve discussed the lead/lag issue previously. A full understanding of why CO2 changes in precisely the pattern that it does during ice ages is elusive, but among the most plausible explanations is that increased received solar radiation in the southern hemisphere due to changes in Earth’s orbital geometry warms the southern ocean, releasing CO2 into the atmosphere, which then leads to further warming through an enhanced greenhouse effect. Gore’s terse explanation of course does not mention such complexities, but the crux of his point–that the observed long-term relationship between CO2 and temperature in Antarctica supports our understanding of the warming impact of increased CO2 concentrations–is correct. Moreover, our knowledge of why CO2 is changing now (fossil fuel burning) is solid. We also know that CO2 is a greenhouse gas, and that the carbon cycle feedback is positive (increasing temperatures lead to increasing CO2 and CH4), implying that future changes in CO2 will be larger than we might anticipate.
  • Kilimanjaro Gore is on even more solid ground with Kilimanjaro. In the movie, the retreat of Kilimanjaro is not claimed to be purely due to global warming , but it is a legitimate example of the sort of thing one expects in a warmer world, and is consistent with what almost all other tropical mountain glaciers are doing. There is indeed some ongoing discussion in the literature as to whether or not the retreat of ice on Kilimanjaro is related to the direct effects (warming atmospheric temperatures) or indirect effects (altered patterns of humidity, cloud cover, and precipitation influencing Kilimanjaro’s ice mass) of climate change, and that argument isn’t yet over. But these arguments would be of more relevance if (a) we were not witnessing the imminent demise of an ice field that we know has existed for at least the past 12,000 years and (b) most of the other glaciers weren’t disappearing as well.
  • Drying up of Lake Chad It is undisputed that Lake Chad has indeed shrunk rapidly in recent decades. While irrigation and upstream water use are probably contributing factors, the dominant cause is the reduction of rainfall across the entire Sahel from the 1950s to the 1980s and with rainfall today still substantially below the high point 50 years ago. There is substantial evidence that at least a portion of this drying out is human-caused. A few recent papers (Held et al, PNAS; Chung and Ramanathan and Biasutti and Giannini) have addressed causes ranging from Indian Ocean changes in sea surface temperature to the increase in atmospheric aerosols in the Northern hemisphere. Gore uses this example to illustrate that there are droughts in some regions even while other areas are flooding. Unfortunately this is exactly what the models suggest will happen.
  • Hurricane Katrina and global warming Katrina is used in the film as a legitimate illustration of the destructive power of hurricanes, our inability to cope with natural disaster, and the kind of thing that could well get worse in a warmer world. Nowhere does Gore state that Katrina was caused by global warming. We discussed this attribution issue back in 2005, and what we said then still holds. Individual hurricanes cannot be attributed to global warming, but the statistics of hurricanes, in particular the maximum intensities attained by storms, may indeed be.
  • Impact of sea ice retreat on Polar bears As we presaged in August, summer Arctic sea ice shattered all records this year for the minimum extent. This was partially related to wind patterns favorable to ice export in the spring, but the long term trends are almost certainly related to the ongoing and dramatic warming in the Arctic. Polar bears do indeed depend on the sea ice to hunt for seals in the spring and summer, and so a disappearance of this ice is likely to impact them severely. The specific anecdote referred to in the movie came from observations of anomalous drownings of bears in 2004 and so was accurate. However, studying the regional populations of polar bears is not easy and assessing their prospects is tough. In the best observed populations such as in western Hudson Bay (Stirling and Parkinson, 2006), female polar bear weight is going down as the sea ice retreats over the last 25 years, and the FWS is considering an endangered species listing. However, it should be stated that in most of the discussions about polar bears, they are used as a representative species. Arctic ecosystems are changing on many different levels, but it is unsurprising that charismatic mega-fauna get more press than bivalves. In the end, it may be the smaller and less photogenic elements that have the biggest impact.
  • Impact of ocean warming on coral reefs Corals are under stress from a multitude of factors; overfishing, deliberate destruction, water pollution, sea level rise, ocean acidification and, finally, warming oceans. The comment in the movie that rising temperatures and other factors cause coral bleaching is undoubtedly true. Bleaching episodes happen when the coral is under stress, and many examples have been linked to anomalously warm ocean temperatures (Australia in 1998 and 2002, all over the Indian Ocean in recent years). Corals are a sobering example of how climate change exacerbates existing vulnerabilities in eco-systems, potentially playing the role of the straw that breaks the camel’s back in many instances.

Overall, our verdict is that the 9 points are not “errors” at all (with possibly one unwise choice of tense on the island evacuation point). But behind each of these issues lies some fascinating, and in some cases worrying, scientific findings and we can only applaud the prospect that more classroom discussions of these subjects may occur because of this court case.

492 Responses to “Convenient Untruths”

  1. 251
    Dave Rado says:

    Re. Rich, 243:

    Thirty years ago I had climatologists telling me that we could experience a “glacial blitzkrieg” in less than a decade (from the same CO2 data).

    This is another myth, as far as peer reviewed science is concerned. See here. You are confusing popular news articles (and a fairly small number even of those) with peer reviewed science.

  2. 252
    J.S. McIntyre says:

    re 248.

    “some would argue for the purpose of evoking fear”

    Rhetorical question:

    If you knew with any certainty that the likelihood was strong that your chidren’s and grandchildren’s lives would be compromised in terms of resources, health and safety, would you fear for them?

  3. 253
    Hank Roberts says:

    Rich, you write:
    > Thirty years ago I had climatologists telling me

    Name one. Just one.

    > …a “glacial blitzkrieg”

    in quote marks — got a source? Who are you quoting?

    Why do you believe what you think you know?
    You’re claiming personal recollection. Name one name.
    You’re using quotation. Name one source.

    Let’s give you the benefit of all the doubt.

    You may not be a troll.
    You may not be posting well known nonsense on purpose.
    You may not be trying to stir up people for fun
    You may not be posting stuff from the PR sites knowingly.

    But a little bit of reading would save you from the appearances.

    Why do you believe what you’re posting is true?
    What source do you trust for the things you’re posting?
    Do you have a science library near you?
    Do you know and rely on a good reference librarian?

    See, you’re managing to hit all the wrong notes on your first appearance.

  4. 254
    Dave Rado says:

    Re. J.S. McIntyre, #245:

    “But it is a political film,…”

    Red Herring. If you want to make a case for this being “political”, please respond to 44. Otherwise, you are making a hand wave of no substantive power.

    In the context of the ruling and this thread, the judge had the following to say:

    “It is now common ground that it is not simply a science film – although it is clear that it is based substantially on scientific research and opinion – but that it is a political film, albeit of course not party political. Its theme is not merely the fact that there is global warming, and that there is a powerful case that such global warming is caused by man, but that urgent, and if necessary expensive and inconvenient, steps must be taken to counter it, many of which are spelt out.”


    “the Defendant, does not challenge that the film promotes political views”

    In #44 you asked:

    What political ends were furthered? Please be clear and concise.

    Clearly, the policy end of waking people up to the need for governments to take action on climate change. That in the judge’s sense of the word, is clearly political.

  5. 255
    Rafael Gomez-Sjoberg says:

    Re 229.

    Rich, I should apologize for the tone of my previous post. I shouldn’t have attacked you personally in the way I did. But too many people come here to post nonsense statements and I start getting annoyed and trigger-happy.

    So, back to the science. The following statement of yours makes no sense:
    “His conclusion that the reader accept his conclusion or a “mysterious” alternative doesn’t wash as truth. CO2 solubility decreases with rising ocean temps…that’s not very mysterious and it’s also a logical alternative!”

    Decreased CO2 solubility is not at all a “logical alternative” to the observed increase on atmospheric CO2 for a few simple reasons:

    1) If the decrease in CO2 solubility were responsible for the observed increase in atmospheric CO2, we still have the problem of figuring out what happened to the huge amount of CO2 we have produced. If the oceans were currently outgassing large amounts of CO2, we would have a much larger increase in atmos CO2 than what has been measured. The increase in the atmosphere would be equal to what we produced plus what the oceans would emit. However, the increase is *less* than what would be if *all* of the CO2 we have produced had stayed in the atmosphere. As I said earlier, we have produced much more CO2 than what has accumulated in the atmosphere, so a lot of that human-produced CO2 has gone somewhere other than the atmosphere (mainly the ocean). Your reduced ocean solubility hypothesis cannot explain any of this. That’s why you would have to resort to some mysterious mechanism for removing *all* or most of the CO2 we have produced.

    This is all easily sorted out by asking: Where is all that CO2 us humans have injected in the atmosphere if the observed increase in CO2 is *not* caused by us as you claim?!?!?!

    At some point, if we don’t do anything about global warming, the oceans will indeed start outgassing CO2 due to reduced solubility as they warm. But we are not there yet, and hopefully we won’t reach that point.

    2) Decreased CO2 solubility in the oceans cannot explain, and is actually directly contradictory, with the fact that the absorption of anthropogenic CO2 has been measured in the ocean. A good reference for this is here:

    3) The change in C13/C12 isotopic ratio of the atmospheric CO2 would not match so well with what is expected from CO2 produced by burning fossil fuels.

  6. 256
    Dave Rado says:

    Re. J.S. McIntyre, 235:

    “The accompanying slides refer to SARS, antibiotic-resistant tuberculosis and avian influenza. If there is a link between climate change and the spread of these diseases, it is not very direct and there are other factors that are far more important. It gives a misleading impression of what is driving the spread of these diseases.”

    Here I do believe you might have a point, BUT … wasn’t malaria and a variety of other diseases also mentioned, diseases that DO thrive in warm climes?

    Malaria is another bad example (like Kilimanjaro).

    For example, the IPCC TAR Working Group II, states:

    “Malaria was successfully eradicated from Australia, Europe, and the United States in the 1950s and 1960s, but the vectors [i.e. the mosquitoes] were not eliminated (Bruce-Chwatt and de Zulueta, 1980; Zucker, 1996). In regions where the vectors persist in sufficient abundance, there is a risk of locally transmitted malaria. This small risk of very localized outbreaks may increase under climate change. Conditions currently exist for malaria transmission in those countries during the summer months, but few nonimported cases have been reported (Holvoet et al., 1983; Zucker, 1996; Baldari et al., 1998; Walker, 1998). Malaria could become established again under the prolonged pressures of climatic and other environmental-demographic changes if a strong public health infrastructure is not maintained. A particular concern is the reintroduction of malaria in countries of the former Soviet Union with economies in transition, where public health infrastructure has diminished (e.g., Azerbaijan, Russia).” [Emphasis added.]

    This is a very cautious statement. It makes it quite clear that malaria is not a tropical disease (stating that is was eradicated from temperate regions only quite recently); it states specifically in its third sentence that Anopheles mosquitoes (i.e. those that could carry malaria) do currently live in many temperate countries; and it makes it clear that the reintroduction of malaria into temperate regions due to climate change is highly unlikely, except possibly in countries whose health services break down.

    Better examples of diseases that are likely to move north as a result of climate change would have been tick borne encephalitis and West Nile virus. The less severe winters in Sweden are already thought to be causing an increase in tick borne encephalitis.

    A better examples of a disease that is likely to become more widespread (rather than moving north) as a result of climate change is cholera (see IPCC).

    So as in the case of Kilimanjaro and Lake Chad, the point Gore was making was sound but the examples of diseases that he gave were very badly chosen.

  7. 257
    J.S. McIntyre says:

    re 256.

    I stand corrected. Thanks.

  8. 258
    J.S. McIntyre says:

    re 254:

    Clearly, the policy end of waking people up to the need for governments to take action on climate change. That in the judge’s sense of the word, is clearly political.


    Now, when you hear the word “political” being used in the context of the movie by climate skeptic/denialists, do you believe that they are doing so in the same context as the judge?

    In the judges context of the word it’s pretty much of what I was saying about the movie in 44 – this is a social, human issue. Government is a biproduct of our need to socially interact, to govern our affairs.

    But when you see someone arguing against the movie and AGW at the same time, I would argue the word is viewed in a different context re AGW is a “liberal” position, as reflected by the conservative leanings of the skeptics.

  9. 259
    dhogaza says:

    Milloy at his best (from the link above):

    Gore also says in the film that 2005 is the hottest year on record. But NASA data actually show that 1934 was the hottest year on record in the U.S. — 2005 is not even in the top 10.

    Comparing apples to oranges ummm global temp record to the US record.

    This dishonesty of this man never ceases to amaze me.

  10. 260
    Dave Rado says:

    re. #252, to fear for one’s children is one thing; for them to have fears of their own that keep them awake at night (this has been documented by some psychiatrists), and that to some extent may be overblown (e.g. if they believe that Manhattan is likely to be flooded suddenly within their lifetime), is another thing entirely.

    Part of the problem is that so much of the debate has been couched in either alarmist (“apocalypse is imminent, so there’s nothing we can do”) or denialist (“there’s no need to do anything”) terms. Mainly because both extremist viewpoints sell newspapers/TV ads, whereas a more rational approach does not.

  11. 261
    J.C.H. says:

    I guess I missed the book in Al Gore’s Presidential Library containing the chapter celebrating the fantastic zenith of his Machiavellian shrewdness.

  12. 262
    David B. Benson says:

    Rich — Orbital forcing theory offers a very good explanation of the paleoclimate data for at least the last 3.8 million years. Using this to predict the future, baring anthropogenic influences, the earth should be gradually cooling now, moving towards a stab at a stade in about 20,000 years.

  13. 263
    Timothy Chase says:

    joe (#248) wrote:

    In the context of showing AIT to school children in a classroom setting, which is what the judge was considering, can it not be argued that the so-called nine “errors” were presented in the movie in a manner that was at least a bit misleading (some would argue for the purpose of evoking fear) to the minds of 10 year olds.

    Interesting question.

    If you say that global warming will result in droughts, water shortages, rising sea levels, etc., what time-frame is a ten year old likely to be thinking in terms of? Next week, perhaps? Or next year? Typically I suspect that kids that age will do a great deal better at it than this, but…

    … was at least a bit misleading(some would argue for the purpose of evoking fear) to the minds of 10 year olds.

    … some would argue, and sometimes kids will get spooked by anything which suggests that the world isn’t always a safe place, that it might be vulnerable to disasters. However, I when the movie was produced, it wasn’t produced specifically for ten year olds.

    It was meant for a wider, generally older audience who realizes that a quick, early disaster may stand in as a symbol for later, more prolonged disasters, helping one to think of what may come not simply in cold, abstract statistical terms but in terms of the human impact of disasters. Thus for example, Katrina can stand in for rising sea levels, even though Katrina was a relatively quick disaster, and rising sea levels will be much more prolonged – but will in all likelihood require that we abandon major cities, in some cases (even given a fairly conservative estimates of sea level rise) within this century itself.

    We don’t know what the exact time scale is for the sea level rise, and the movie doesn’t pretend to say. The IPCC gave one set of estimates earlier this year in the neighborhood of half a meter within this century, Hansen has said that given the nonlinear response of ice and the paleoclimate record five meters would be more realistic, and more recently it looks like in light of recent events the IPCC may be getting ready to revise upwards to between one and two meters. However, on the scale of centuries we can be pretty confident that it will be in the tens of meters.

    At a certain level, beyond a certain point, the speed of the disaster becomes irrelevant. This isn’t an is of politics, but an issue of ethics for humanity as a whole. Even if the worst of the disasters brought about by climate change do not happen in my lifetime, they will happen to someone, in fact to a lot of people, and they will affect the legacy of our world that we leave to future generations – in all likelihood in dramatic ways for the next thousand centuries.

    The relevance of a thing should not end where it no longer directly affects my life. As a human being I should recognize the importance of what happens to others, to be able to identify with those I do not know or who may not live until long after I am gone.


    But ten year olds…

    I think the movie would be an excellent beginning for a discussion of what cities are, what kind of investment they entail, the vulnerability of aquifers, sewer systems and subways to rising sea levels even when the surface of the city remains above water, and why you can’t simply expect to pick up a city and move it. Discussions of the dependence of agriculture upon a stable climate, including its patterns of rain. Discussions of long-term planning and of the investments required for long-range human action.

    This would give people an opportunity to deal with whatever shortcomings the movie might have for an audience of ten year olds and would give them a deeper understanding of the modern world which will soon be theirs, then theirs to pass on.

  14. 264
    PHE says:

    The hysteria of the pro-AGW commentators here really paints a picture.

    The only reason that ‘climate cooling’ of the 60’s/70’s didn’t result in a solid load of peer-reviewed papers is that it didn’t last long enough. If it had, the very same people crying out about AGW would be crying about polar bears starving due to not being able to catch fish through the ice, of the threat of growing glaciers, increased rainfall and flooding, etc, etc.

  15. 265
    Joe Duck says:

    With a warming debate raging over at my blog after I criticized the film “An Inconvenient Truth” for it’s obvious hyperbole, I find myself searching for “expertise”. Here I thought I’d find it, and I’m ready to burn my M.S. if this kind of advocacy is what science has become.

    Clearly you are climate experts, but clearly you are applying some odd and non-scientific standard to the *implications* of the film, which are far more relevant than the specific factual statements. Facts become increasingly irrelevant when presented out of any context, and the film is a perfect example of using true statements to lead people towards unreasonable, catastrophe conclusions.

    You seem to defend the clear implication of the film that sea levels are going to rise catastrophically and that Katrina was caused by Global Warming. You do this by stating that the film provides some qualifications as if that somehow makes the implications true. It does not make the implications true. As you know very well (but very few watching the film could possibly know), no responsible researcher would say “Katrina was caused by GW” and no responsible researcher would conclude that “sea levels are likely to rise twenty feet”. This line | is (approximately) the IPCC’s estimate of average sea level rise. This could have some ominous implications but it doesn’t compare to calving glaciers and flooded coastlines.

    I’ll try to leave my respect for your scientific credibility intact while I read more, but you sure are suckers for alarmism thata supports your grant budgets, and defending it is unbecoming at the least, and unscientific at the worst.

  16. 266
    Ray Ladbury says:

    Re 243. Rich, Why the hell would you want to believe me. That’s not what I’m asking you to do. I am asking you to familiarize yourself with the science–peer-reviewed, generally accepted, consensus science. If you do, you will find that:
    1)GCMs include H20 as both a driver and a feedback
    2)No. There was no consensus on a “glacial blitzkrieg” or ice age or whatever else Rush has called it.
    3)Human beings have actually produced more than enough CO2 to account for the increased amount in the atmosphere. The rest has gone mainly into the oceans, whose ability to absorb ever more CO2 may be diminishing.
    4)The content of C-13 in the atmosphere is decreasing. This indicates that the source of the new carbon is largely fossil, since living organisms tend to be composed of carbon richer in C-12 than the background.

    And lots, lots more. I would also be very interested in where you have been getting your information. It really strikes me as odd that you would come on so strongly saying climate scientists don’t know what they are talking about on a site run by professional climate scientists. Not every source is equally reliable. Stick with peer-reviewed (at a minimum) literature or sources that derive their facts from peer-reviewed and generally accepted research.
    And if I have been harsh on you, I apologize. The trashing of good scientists by ignorant food tubes like James Inhofe has my back up.

  17. 267
    Ray Ladbury says:

    And Michael, I must apologize to you as well if I have been harsh. It does get tiring addressing the same contrarian arguments over and over. I hope that I was able to convey at least one point: there is a huge difference between saying a scientific field is “settled” and saying it is mature. In a mature field, we still expect breakthroughs in our understanding, but these will not change the basics of the theory. For instance, we will likely understand aerosols better in 10 years, but would you expect a change in magnitude of forcing due to aerosols to change our understanding of CO2 forcing in which we have high confidence or some other forcing we do not yet understand? The state of our understanding of global climate is comparable to our understanding of, say, semiconductors. We continue to learn new things, but the theory stays the same.

  18. 268
    Dave Rado says:

    Re. 258, I agree, words are often ambiguous, and parts of the press take advantage of that fact. In its strict definition, the film is political, and the judge ruled on that basis; but the denialist press has twisted this to imply “left wing”. The judge should have made it explicit that not only did he not think it was party political but that he also didn’t think it it was political in the left-right sense of the word.

    Similarly he should have referred to “alleged errors” rather than “errors”, and stated explicitly that he wasn’t ruling that they were actually errors (which it is clear that he wasn’t if you read the judgement carefully) – a failing of his which the denialist press has also twisted to its advantage.

  19. 269
    Timothy Chase says:

    RE Arctic Sea Ice

    Just a quick note regarding the arctic sea ice this year…

    It has been recovering noticeably since about 1 Oct 2007 and more so as time goes on. However, the recovery has been very weak when compared against previous years. In fact the Arctic Sea Ice Anomally has plummeted to below -2.75 million square kilometers and would appear to be still falling. Tough to say – as it is now quite literally off the charts.

    Please see the charts “Hemispheric Anomaly” or “Tale of the Tapes” at:

    Cryosphere Today

  20. 270
    dhogaza says:

    Clearly you are climate experts, but clearly you are applying some odd and non-scientific standard to the *implications* of the film, which are far more relevant than the specific factual statements.

    Care to provide some specifics to back up this blatant ad hom attack on the owners of this site?

    Or are we just supposed to take your word on it?

  21. 271
    David B. Benson says:

    What is one to do in the face of this?


    [Response: I’d complain about the journalist. I’ve talked to Marburger on a number of occasions and he very clearly ‘gets it’ – no denial there. This piece is more of a ‘gotcha’ piece of journalism where normal caveats are taken out of context in order to fit an pre-existing frame. – gavin]

  22. 272
    J.S. McIntyre says:

    re 271

    Um…Don’t worry, be happy?


  23. 273
    Dave Rado says:

    Re. 264. P.H.E.

    The hysteria of the pro-AGW commentators here really paints a picture.

    Which post(s) are you referring to? In what specific way do you consider them to be hysterical? Resorting to blanket insults that you are unwilling to back up with a single concrete example is hardly the behaviour of someone who has any interest in the truth.

    The only reason that ‘climate cooling’ of the 60’s/70’s didn’t result in a solid load of peer-reviewed papers is that it didn’t last long enough.

    Where did you get that idea from? Please cite your sources.

    If you really want to know about the history of the science, rather than just spouting uninformed opinions, start here. But from your posts you come across as someone who would never let an inconvenient fact get in the way of a good opinion.

  24. 274
    Mary C says:

    Re 260. Have you seen AIT? It is far from an alarmist, “there is nothing we can do,” presentation. I constantly wonder where that idea comes from. It seems to me that your characterization of the two sides is confused. Those scientists who believe that global warming is real and that it is largely human-caused wouldn’t bother to participate in something like the IPCC or to sustain a website like RealClimate if they were promulgating the idea that it’s hopeless. What articles in the media can you point to that make the claim that “apocalypse is imminent, so there’s nothing we can do”? If there are some–which there well may be–they’re rare enough that those are not the ones that come to mind for me. Rather, it is the claims, or perhaps more accurately the accusations, of the denialists about those with whom they disagree that the other side is “alarmist” than any actual “hysteria” (see 264) on the part of climate scientists and others who accept the likely reality of global warming.

    As for the children, well, various recent generations have grown up with things like the Depression, World War II, the Cold War (anyone remember “duck and cover,” air raid drills–yeah, those school hallways alwasy seemed so safe, backyard bomb shelters?), and terrorists who bomb buildings, to say nothing of the more visible threats of, for example, polio and other diseases. Life–and bad stuff–happen.

  25. 275
    Ray Ladbury says:

    Joe Duck, it is a rather novel standard to which you are holding Mr. Gore. I mean, he’s responsible not just for what he says, but also for you YOU think he implies or what a “ten-year-old” thinks he implies, or what an imbecile thinks he implies. I wonder how your own missive might fare under such a standard. After all, you are clearly implying that the prime motivation of the contributors is supporting their “grant budgets”. This could be interpreted as alleging scientific fraud.
    For whatever reason, Al Gore has become the whipping boy of the anti-environmentalists–the man they love to hate. Do you think that maybe your view of the film might be colored by your clear antipathy toward the man? Do you realize that at this point your opposition only elevates his status?

  26. 276
    Dave Rado says:

    Re. #271, it’s a very confused article that you linked to. The headline and the article contradict each other. The headline is “Bush climate advisor says temperature change won’t ‘affect people’s lives, not linked to events'”. But in the article, he only seems to be saying that 2 degrees C isn’t a “magic number”, and that things could get very bad with a less than 2 degree rise:

    “While admitting that humans are producing too much carbon dioxide, he added, “you could have emerging disasters long before you get to two degrees… There is no scientific criterion for establishing numbers like that.”

    So logically he’s really saying that the emissions reduction targets need to be much tougher than the EU, with its 2 degree C stabilisation target, is arguing for. But the headline implies that he’s saying the opposite of that.

  27. 277
    Mary C says:

    Re 264. Ae you saying that if we now found ourselves in cooling off period that had already lasted for over forty years, it would be inappropriate for scientists to be looking into the causes of that cooling off, the potential for continuation or worsening of the pattern, the implications for human beings and other living creatures, and possible mitigation efforts to avoid the worst of the problems?

  28. 278
    J.C.H. says:

    David B. Benson Says:
    19 October 2007 at 5:06 PM

    What is one to do in the face of this?

    Perhaps hope for the return of the days when America had leadership that paid attention to its climate scientists:

  29. 279
    Nick Barnes says:

    Timothy Chase @269: yes, I’ve been watching the Tale of the Tape for most of this year.
    What I would like from CT is more raw data, but their graphs are very striking.

  30. 280
    Dave Rado says:

    Also re. #271, Marburger’s statement that there are no scientific criteria for the 2 degree stabilisation target is also rather puzzling – see for example Oppenheimer and Petsonk, 2004.

  31. 281
    Hank Roberts says:

    > leadership that paid attention to its climate scientists

    Yeah. Last time was probably around 1776.

  32. 282
    S. Molnar says:

    Re #271: I haven’t seen the full transcript, but it seems to me that Marburger is making a very narrow point, that there’s nothing magical about 2 degrees, as opposed to, say, 1 or 3 or 2.1, which can easily be interpreted by the unsophisticated listener (e.g., the president of the United States) as meaning there’s no problem with an increase of 2 degrees. There was a time when only lawyers spoke that way, but now science advisers are in on the act.

  33. 283
    Figen Mekik says:

    Did anyone watch John Stossel on 20/20 tonight about how global warming is not happening and the IPCC is made up of government appointed officials… He ends with Gore saying “the debate is over” and actually says “the nobel winning vice president may say the debate is over but I say it’s not.”

    Who is this Stossel guy? A comedian?

  34. 284
    John Mashey says:

    re: #281 Hank
    Now, now, not quite that bad…

    Actually, even skipping Clinton/Gore, we find the following from George H. W. Bush Nov 7, 1989, who perhaps was listening to climate scientists:

    He at least *says* that stabilization of CO2 should be achieved as soon as possible… obviously a different Republican party … which is a reminder that climate change should never have been a general partisan political issue, except that it was convenient for some people to make it so.

  35. 285
    S. Molnar says:

    In view of gavin’s reply to #271, I retract the last sentence of my previous post: I have no basis for comparing Marburger to a lawyer (and some of my best friends are lawyers – really).

  36. 286
    Ray Ladbury says:

    Re 271 and 285. Marburger is not well, and in any case it can’t help that any credibility he had was lost when he didn’t resign when the administrations attitudes toward science became clear.

  37. 287
    Mark says:

    A quick tangential note of thanks here from a long-time reader and first time poster. I’m not sure if you folks at have ANY idea what an immense public service you are performing. Please know that it is greatly appreciated by thousands of (often) anonymous readers like myself. In the vast sea of questionable “information” that is the internet, it is invaluable to have a place to go to run by real climatologists. Even with your occasional dry-witted (and understandable) cracks toward the denial media, your articles are incredibly even-handed and the discussions surprisingly civilly moderated. I have relied on this site countless times to inject sanity into “debates” on blogs and discussion forums. You are measurably helping to undo the confusion engendered by more than a decade of industry-sponsored disinformation, a sometimes hapless and passive (if generally well-meaning) mainstream media, and a public that is often woefully undereducated for interpreting scientific news and therefore easy prey for those whose goal it is to obfuscate.

    All that glowing adulation aside, I did feel you were a tad generous with Mr. Gore on one point. Getting the “tense” wrong on the evacuations – even if there is little doubt that they are going to occur – is exactly the kind of tolerance for error (without quotation marks) that the denial crowd loves to inflate out of proportion in their desperate attempt to impugn an otherwise sound and thorough rebuttal of the unfortunate court ruling by a non-climatologist judge. It’s important to rigorously call a spade a spade in such a review. Otherwise, you unnecessarily draw into question the objectivity that *I* happen to know (from reading dozens of other pages here) that you are honoring during the other 99% of your discussion. Remember that people like me are directing non-scientists – some of them very skeptical and already predisposed against the scientific community by the drivel they are reading elsewhere – to your site. While much of the discussion here may fly right over their heads (even with the impressively cogent and clear writing), something as simple as “present versus future tense” is at an elementary school level that anyone can “latch onto”. While it’s a tall order to make your discussions 100% bulletproof to someone who may already have their mind made up to dismiss them, lax moments like that make things too easy for them.

    Again, a deep and grateful bow of kudos to all of you here. I take it that this site is self-funded, but if you ever run into trouble in that area I do hope you would make your readers aware. This is a public resource that should NEVER go away.

  38. 288
    Dave Rado says:

    Re. #274, Mary C, I didn’t say that Gore’s movie is alarmist overall, but many respected climate scientists believe that a few parts of it were presented in an alarmist way (and the judge also ruled that this was the case). See for example James Annan’s take, or William Connolley’s, or Bob Ward’s comments in this thread (Bob was until recently the UK Royal Society’s senior manager of policy communication).

    And I didn’t mean that alarmist presentations *state* that there’s nothing we can do, but rather that the effect on the public of alarmism tends to be one of creating despair and of the feeling that there’s no point in acting because apocalypse is inevitable. As for alarmist articles in the media, they appear all the time and Realclimate mentions them regularly – e.g. see here (where Stefan writes “I reject the hype in a recent article in the Independent about a “point of no return” for CO2 emissions.”). Or see Gavin’s criticisms of the BBC’s Global Dimming programme. There are many, many other examples of realclimate articles criticising media hype of this sort.

    The Australian Academy of Science’s rebuttal of Swindle starts by saying:

    It is both exasperating and unfortunate when the media either exaggerate stories, sometimes to idiotic degrees, or air poorly-vetted and inaccurate presentations that are purported to provide journalistic balance. It has been so for global warming ever since the topic burst into the media in the late 1980s with images of floods, droughted crops, storms, lightning bolts, cracked clay pans, carcasses in deserts, and people in deck-chairs on the beach up to their necks in sea water. This has created vividly false impressions. Now the TV program ‘The great global warming swindle’ (aired on Australian Broadcasting Corporation television on 12 July 2007) presents a counter story with even greater, but opposite, exaggeration and inaccuracy. What can the man in the street make of this? How can the publics’ right to be well informed be addressed by such polarizing and incompatible presentations in the media? Is human-induced climate change the biggest threat to the world this century, or is it just a fraudulent claim by climate scientists trying to drum up research dollars?

    My post in #260 was not in any case meant to be a specific criticism of AIT but rather I was making the general point that the media’s love of controversy and sensationalism has often given the uninformed public a false and counter-productive impression; and also that (in response to #252) that it is possible to be irresponsible about how one presents the science to children.

    True science is full of nuances, which it is difficult to convey in popular presentations, but one should try to convey them nevertheless.

  39. 289
    Timothy Chase says:

    Nick Barnes (#279) wrote:

    Timothy Chase @269: yes, I’ve been watching the Tale of the Tape for most of this year.

    What I would like from CT is more raw data, but their graphs are very striking.

    Heck, I have seen the raw data – or at least links to the massive files that I could download if I really wanted to. Graphics, if I remember right. Then its pixel counts, more or less. In this case I would be more than happy to settle for some processed data.

    Ideally, whenever you make available a chart along these lines (assuming it isn’t any more trouble than a moment’s thought) make available the data at different levels of processing. I don’t mind a megabyte or more if its just numbers – and the appropriate labels. Oh… and with description… and sourcing.

    Jeez! Beginning to sound like some perverse Christmas wish-list – and I don’t know if the guy still has a place to call home. (Sorry… black humor. Probably too much Trent – or something.)

    Anyway, I wouldn’t be at all surprised if next year is another jaw-dropper. Especially with the “recovery” we are seeing so far.

  40. 290

    Rich writes:

    [[One problem keeps gnawing at me (besides the oceans representing the biggest natural CO2 interchange) is why water vapor is always left out. It’s by far the most important & effective GHG and I’ve seen models that would explain the atmosphere’s CO2 increase as a result of increased H2O.]]

    Water vapor is not left out. Every global climate model in the world accounts for radiative transfer due to water vapor.

    [[ Again, using Rafael’s (and my students’ logic) it would be a small step to believe that WHATEVER process began heating the Earth 10,000yrs ago (that’s 9,900yrs before serious anthropogenic CO2) continues to increase the evaporative process, which continues to increase oceanic release of CO2.]]

    The ocean emits about 90 gigatons of carbon dioxide a year. It absorbs about 92 gigatons. So the oceans are a net sink for CO2, not a net source.

    [[ Please…I don’t need any of the personal attacks – I realise that significant amounts of anthropogenic CO2 from hydrocarbon use have been released. I’m also aware of the temperature increase over the past 100yrs. I have seen models that support myriad reasons why these two occur. I’m not arguing against anthropogenic causes…I just don’t see enough empirical evidence to support one model over another.]]

    Then you’re not familiar with the bulk of the evidence. Try here:

  41. 291
    J.S. McIntyre says:

    “In the context of showing AIT to school children in a classroom setting, which is what the judge was considering, can it not be argued that the so-called nine “errors” were presented in the movie in a manner that was at least a bit misleading (some would argue for the purpose of evoking fear) to the minds of 10 year olds.”

    Here’s a thought re children, fear and resiliency:

    I’m reminded as I read Tom Holland’s history of the fall of the Roman Republic, “Rubicon”, the Romans never raised their children as “children”, but to be the people their parents believed they should be, beliefs dictated by gender roles, societal perceptions, competition and so forth. I recall reading somewhere that even in the 19th century, children were still viewed as “small adults”. As I understand it, this is not an exception; we see in varying times and cultures that children, by and large throughout history, have not lived the sweet, uncorrupted and free-of-the-world’s-horrors lives we seem to imagine our children of this era live. (And we’re not even touching upon the effect of war and starvation, religious fanaticism and so forth upon inflicted upon children worldwide.)

    Yet somehow, through all of this, in spite of less-than-ideal childhoods (by our “standards”) humanity still ended up with dreamers and scientists, writers and historians, great leaders and people of compassion … people of exceptional ability, people who, both publicly and privately, often in ways we’ll likely never know, helped to make life better for the people around them, either directly or by virtue of their creativity.

    I’m a child of the “duck-and-cover” 50s. I grew up with the bomb. We all did. Now while we could probably devote wings of libraries to the psychological effects and societal implications of a generation of children raised in this fashion, the simple truth is we turned out okay. If anything, a good portion of us grew to not only fear the bomb, but to respect its power to destroy our civilization.

    So pardon me if I’m not getting too worked up about exposing children to a very real threat that, when they reach their majority, will likely have a great and deleterious effect upon their existence. If anything, they might grow to respect and understand the power inherent in the climate, something far too many people seem oblivious to.

    But whatever happens, their psyches will likely do just fine, that you very much. Children are nothing if not resilient.

  42. 292
    Bob Ward says:

    Re #268

    I think you are being a bit harsh on the Judge, Dave. Take a look at his full ruling at:, particularly point 40. You see that the guidance distributed with the film now states: “AIT promotes partisan political views (that is to say, one sided views about political issues)”. You can also see that the judge uses the word error in inverted commas. I think he did a reasonable job. He assessed the nine points against the consensus position represented by the IPCC’s Fourth Assessment Report, and the Government in its defence was aided by Peter Stott of the Met Office, who appears not to have contested that the film differed from AR4 on these points.

    Point 9 of the Judge’s ruling is also interesting, because a representative for the Government gives the following explanation for distributing the film:
    “8. …I should say at once that it was recognised from the start that parts of the Film contained views about public policy and how we should respond to climate change. The aim of distributing the film was not to promote those views, but rather to present the science of climate change in an engaging way and to promote and encourage debate on the political issues raised by that science.”

    It is a shame that the Government could not find a better way of presenting the science of climate change in an engaging way. Instead, through it’s actions, it has now encouraged Viscount Monckton and his cronies to distribute to schools ‘The Great Global Warming Swindle’ along with his own Christmas pantomime (full of fantasy and fiction) about climate change (presumably based on the flawed logic that two wrongs make a right):

    Pity Britain’s schoolchildren!

  43. 293
    Dave Rado says:

    Re. #292 (Hi Bob):

    “Re #268

    I think you are being a bit harsh on the Judge, Dave … You can also see that the judge uses the word error in inverted commas”

    He did, but that is a subtlety that was missed in almost every media report of the ruling (even the BBC, The Independent and The Guardian missed it, and they are hardly denialist in outlook); and in my opinion the judge should have realised that it would be missed and that he needed to spell out that he was referring only to “alleged errors” and was not ruling that they were actually errors (see also here).

    Similarly, as you say, all the judge seems to have meant by “political” was that it expressed views about how one should respond to climate change, whereas many of the press reports have implied that he meant “left wing” or “liberal” or “part of the environmentalist lobby”, which he didn’t mean; and in my opinion, he should have realised that his ruling was likely to be misreported in this way, and he should have made it clearer at the head of the main ruling in an unambiguous way that this was all he meant.

    It is a shame that the Government could not find a better way of presenting the science of climate change in an engaging way.

    Has an engaging documentary ever been made that explains the science effectively? And that explains what the policy options are without doing so in a partisan way?

  44. 294
    J.S. McIntyre says:

    re 292

    “AIT promotes partisan political views (that is to say, one sided views about political issues)”.

    Actually, I believe this reinforces Dave’s point. Regardless of point 9, or to the use of definition in 11, or even the judge’s note in 11 that

    ” Although there was some earlier suggestion on behalf of the Defendant that partisan might relate to ‘party political’, it soon became clear that it could not be and is not so limited.”

    the “partisan” label as used further aids in the misrepresentation of what he was ruling to the uniformed, particularly in light of the understanding that regardless of the merits of the case and the elements that were used to come to a conclusion, it would be inevitable that “partisan” would be interpreted differently re the anti-AGW political spin that followed.

  45. 295

    Re: Mark’s comments in #287. I second those emotions,especially paragraphs 1 and 3. I also agree with the thrust of paragraph 2. Al Gore, nor anyone else involved in calling out the cavalry, have to be right on every point, to be right on the overall picture that global warming is happening and it’s primary cause is the burning of fossil fuels.
    Trying to defend the occasional error by minimizing it, only gives fuel to those with their heads still in the sand.

  46. 296
    inel says:

    Re: 291
    I concur with J.S. McIntyre’s stance as far as children’s resilience, especially when presented with the truth.

    My own two eldest kids (aged 11 and 13) watched AIT with me last year, and it raised questions in their minds that I have tried to answer since.

    By coincidence, the day after the High Court Judgment was handed down, I watched AIT again, this time in a classroom with older pupils and staff at my 13-year-old’s school. Afterwards I attended a session that was deliberately set up to provide “an alternative view” for sixth formers, and this was followed by Q&A moderated by a science teacher. As a result, I think I now have (at least) a fresh perspective on this film and the way it is perceived by students in England in the particular age group for which the climate change pack for schools has been prepared.

    By and large, I think perhaps the student reactions I have encountered so far tend to reflect those of their parents or key leaders in their peer groups. (This is an important point for boys. If they have a “leader” who waxes lyrical on certain well-known arguments, such as the importance of Milankovitch cycles, in an attempt to dismiss anthropogenic influences on climate as insignificant compared to natural factors, it is hard for lads in that group to disagree. This is especially so if, for example, their “leader” is studying Physics at A-level, and his Science or Geography teachers do not have sufficient knowledge nor confidence to point out the flaws in his sceptical argument in class.) Of course, high school students will challenge teachers on particular points that they are familiar with. This is why the Guidance Notes to teaching staff in the climate change pack circulated to state secondary schools in England provide what I would consider to be crucial background material for any Geography or Science teacher, as well as those members of teaching staff in charge of Citizenship studies.

    Certainly, I have watched AIT with students several times this year, and they do NOT appear to find it alarmist (any more than it needs to be to wake dozy adults up from their slumbers and grab the attention of busy people leading busy lives). Even students admit that they are, themselves, far too busy to tackle climate change in earnest, so they can easily see how busy adults may never get around to addressing the issues. Yes, the truth is alarming, and is certainly inconvenient, but the film AIT itself is not half as bad (i.e. excessively scary) as people are led to believe.

  47. 297
    Joe Duck says:

    Mr. dhogaza I certainly don’t mean to be making ad hominem attacks here (though it sure seems to be the standard – this is a scary place even if you think as I do that IPCC is the best standard but AIT was too alarmist).

    You asked for specifics and I certainly thought I was clear with this obvious point:

    You [the post authors] seem to defend the clear implication of the film that sea levels are going to rise catastrophically and that Katrina was caused by Global Warming.

    Are the many scientists / activists participating here saying the film did not exaggerate at all, or that it did not exaggerate enough to be concerned?

    Where in the world would the folks here draw the line with respect to alarmism? IPCC is fairly clear on sea level rise – huge sea level rises attributable to GW are possible, but they are very unlikely. Likely are sea level rises of approximately one to two feet over the next 100 years.

    How in the world can anybody maintain the film made a reasonable case for the most likely scenario of a 1-2 foot sea level rise over the next 100 years?

    Facts and implications are different. If you state factually that several scientists now hypothesize a connection between hurricane strength and global warming and then show pictures of Katrina, the implication for most is that there is a powerful and scientifically documented connection between Katrina and GW.

    The film was designed to spur people to action using a powerful presentation with some alarmist tactics. That’s fine as filmmaking and activism, but the pretense that this was an objective examination of the best data to date is unbecoming to the scientists who are stating that this was an objective, reasoned, unbiased film without any alarmism or exaggeration.

    But I’m starting to get it. We are all silly primates, and rather than stick to the facts and the clear implications of the facts we tend to pick sides and blast away. Science can rise above this tendency, but often scientists cannot. That is too bad, because the stakes here are huge.

  48. 298
  49. 299
    Ray Ladbury says:

    Joe Duck, Excuse me, but Mr. Gore says pretty clearly under which scenarios the various sea level rises he cites apply–melting of Greenland, melting of the WAIS, etc. The fact is that there remains considerable uncertainty about how much melting will occur and how fast. I repeat my point above. You cannot hold someone else responsible for your interpretation of what they say. They are responsible for what they say.
    Look, Joe, I’m not a big Al Gore fan. However, he made a real good faith effort to be consistent with the science as it was accepted at the time. He did a good job at making an entertaining presentation and he deserves credit for it. An academy award, probably not; a Nobel prize–that’s downright funny. However, his status has been elevated to this point because 1)he has stood alone among politicians in calling attention to these risks, and 2)the very vitriol spewed at him by the right exaggerates his importance. So conservatives (real conservatives–not the neocons) need to get a grip. Admit that rejecting sound science and focusing attention on Al Gore aren’t doing them any good.

  50. 300
    Timothy Chase says:

    Hank Roberts directed us to a linear projection of sea rise as a function of temperature in 298:

    Hank, I don’t like it. Doesn’t take into account the positive feedback that we know exists.

    But the graphs look good, and obviously a linear approximation should work for a little bit. Likewise it is a great deal better than the constant rate the IPCC has been using – and will keep having to adjust.

    Given the dynamical response of ice sheets observed in recent decades and their growing contribution to overall sea-level rise, this approximationmay not be robust. The ice sheets may respond more strongly to temperature in the 21st century than would be suggested by a linear fit to the 20th century data, if time-lagged positive feedbacks come into play (for example, bed lubrication, loss of buttressing ice shelves, and ocean warming at the grounding line of ice streams). On the other hand, many small mountain glaciers may disappear within this century and cease to contribute to sea-level rise. It is therefore difficult to say whether the linear assumption overall leads to an over- or underestimation of future sea level. Occam’s razor suggests that it is prudent to accept the linear assumption as reasonable, although it should be kept in mind that a large uncertainty exists, which is not fully captured in the range shown in Fig. 4

    A Semi-Empirical Approach to Projecting Future Sea-Level Rise
    Stefan Rahmstorf
    Science 19 January 2007:
    Vol. 315. no. 5810, pp. 368 – 370

    … and the author is well-aware of the limitations.


    Not happy about it, but definitely an improvement.