Home > Environment > Climate change modellers vindicated

Climate change modellers vindicated

August 16th, 2005

Via Jennifer Marohasy, I found a report on three articles in Science Express that put the closing seal on the most significant issue in the debate about the reality of human-caused climate change: the disagreement between climate models and data from satellites and radiosonde balloons. Now as Real Climate observes “the discrepancy has been mostly resolved – in favour of the models.”

There aren’t many scientifically literate sceptics (that is, people open to being persuaded by evidence, but not yet convinced) left on the global warming issue, and this evidence, along with the continued warming being observed at all levels, should convince most of those who remain. There’s a bit more history over the fold.

The big expert on satellite measurements of climate is John R. Christy of the University of Alabama, who has worked with Roy Spencer. His data, which started in 1979, initially appeared to show a cooling trend in the troposphere. Since satellite data seemed free of many of the errors that affect surface measurements, these results were seized on by global warming ‘sceptics�.

However, it was discovered in 1998 that the satellite data had problems of their own, arising from a failure to correct for the gradual decay in their orbits. Correcting for this, and adding more data, the satellite data now showed a slight warming trend, but not as much as the surface data. More data and alternative analysed reduced the discrepancy somewhat, but it remained a problematic issue. Sceptics also pointed to studies of radiosondes carried on weather balloons. These were much patchier, but also failed to match model predictions.

The latest studies correct errors in the procedures used to derive both satellite and radiosonde time trends, largely eliminating the discrepancy. The most conservative estimates of tropospheric warming, those of Christy and Spencer now show warming of 0.12 C per decade, compared to a surface trend of 0.19 C per decade. Other estimates show tropospheric warming equal to or greater than that at the surface, as predicted by the models.

In view of the predictive success of the models, in which climate change is driven by human-caused accumulation of greenhouse gases, and the repeated failure of empirical challenges, it’s hard to see how anyone without strong preconceptions on the topic can reject the conclusion that, in all probability, we are experiencing human-caused climate change. Most of the models predict that the warming is likely to accelerate in the future.

Categories: Environment Tags:
  1. Dave Ricardo
    August 16th, 2005 at 21:06 | #1

    “Most of the models predict that the rate of change is likely to accelerate in the future.”

    Accelerate, or increase?

  2. jquiggin
    August 16th, 2005 at 21:37 | #2

    Fixed now. Don’t tell Tim Blair about this!

  3. August 16th, 2005 at 22:31 | #3

    Jerry Pournelle might be classed as a scientifically literate sceptic. You can see his latest musings here, here, here and here. He too is incorporating these latest insights into his thinking, but is valiantly resisting where that is taking him.

  4. August 16th, 2005 at 23:58 | #4

    Does the rate at which the story changes not bother anybody? Can we really say we’re now at the end of our journey of discovery on this issue?

  5. Ian Gould
    August 17th, 2005 at 07:13 | #5

    David -accelerate.

    See the recent reports in New Scientist about melting permafrost releasing billions of tons of methane. Methane is a much more powerful greenhouse gas than CO2 but is usually present in much smaller quantities.

  6. Mark Hadfield
    August 17th, 2005 at 07:29 | #6

    RE John Humphreys: “Does the rate at which the story changes not bother anybody?”

    What’s happening now (and has been happening for the last 15 years at least) is that the “story” of recent anthropogenic warming has been becoming more complete and better supported. The different lines of evidence (surface measurements, oceans, glaciers, tropospheric measurements) are all telling more or less the same story.

    The MSU tropospheric “story” is not over. There are still 2 analyses with trends over the last couple of decades of approximately 0.12 K/decade and 0.20 K/decade. (I’m referrring to the analyses usually called UAH and RSS here. I could have the numbers slightly wrong.) They can’t both be correct. I favour RSS, but maybe I’m biased. Longer time series and more careful analyses should reduce these discrepancies.

  7. Helen
    August 17th, 2005 at 09:48 | #7

    Just tangentially, Jennifer Marohasy has now been replaced by Don Burke (!!!) as the environment spokesperson at the IPA/chairperson of the Australian Environment Foundation.

    http://www.theage.com.au/text/articles/2005/07/25/1122143787176.html

  8. wilful
    August 17th, 2005 at 09:48 | #8

    John H, who’s saying the journey of discovery is ending? But who’s saying the story has changed? Is this the new talking point, that climatologists have been inconsistent and we therefore cant believe a word they say? Rubbish. The story has been in the same general direction for decades, the details are firming up daily.

  9. Paul Norton
    August 17th, 2005 at 10:39 | #9

    Helen, Don Burke’s new appointment reminds me of when Harry Butler of “In The Wild” fame became a barrel organ for the Tasmanian Government in 1982 on the Franklin Dam issue.

  10. August 17th, 2005 at 13:02 | #10

    JQ,

    I can understand your eagerness to bash your favourite creationists, but my understanding was that the inconsistency in satellite data was not the key problem with climate models.

    The essential – and continuing – problem with climate models is that they project out over a very long time period an extremely complex simulation. That the models fit historical data is trivial, and expected. This tells us nothing about their ability to predict the future.

    It’s great that we’re learning more, but we don’t have the answers yet.

  11. Mark Hadfield
    August 17th, 2005 at 14:13 | #11

    Re Fyodor “That the models fit historical data is trivial and expected”

    It most certainly is not trivial!

    I was surprised when I first saw results from simulations of the 20th century, showing that with credible estimates of the forcings (solar, aerosols, greehnhouse gases) the climate models reproduce the observed trends in global mean temperature. I had thought the models (and the real world) would have far too much intrinsic variability for this to work. Apparently not.

  12. Chris O’Neill
    August 17th, 2005 at 14:29 | #12

    On ABC’s Landline interview of Don Burke he repudiated the global warming denialist viewpoint and I think he said more environmental funding should be directed towards the issue. So maybe ditching Marohasy is part of an IPA shift on the issue. Unfortunately Landline haven’t put the transcript on their website yet even though the link is on their front page.

    BTW, the worldwide average temperatures for July have been released at http://www.ncdc.noaa.gov/oa/climate/research/anomalies/anomalies.html. This shows we have just had the second warmest July since before 1880 (1998 was the hottest because of El-nino). This follows the second warmest June (1998 hottest), the second warmest May (1998 hottest), the second warmest April (1998 hottest), equal third warmest March, eighth warmest Frebruary and third warmest January. So far 2005 is the second warmest year since before 1880 (1998 is the warmest).

    Of course, this is just a coincidence with record high levels of CO2.

  13. August 17th, 2005 at 15:09 | #13

    Mark Hadfield, it’s called “data-fitting”, i.e. calibrating a model to replicate known historical trends. This is not necessarily helpful in predicting unknown future trends.

  14. StephenL
    August 17th, 2005 at 15:12 | #14

    I suspect the situation with Don Burke is more complex. Judging by things I have seen from him in the past he is genuinely concerned about the environment, but struggles to reconcile this with his generally free market positions, and so has had a rather mixed relationship with the environmental movement.

    When the IPA approached him they probably pitched the position as what they represent the AEF as being – a genuine environmental group that is more pro-free market than the others with a commitment to increased research before lots of money is spent on problems.

    Burke would have been attracted to this, and may not have seen the agenda that those of us with experience of the IPA’s dishonesty on environmental issues expect.

    The IPA scored a coup in getting a high profile and popular frontman, but the downside for them is that he isn’t going to toe their line on everything. Marohasy could be counted on to refuse to believe in any environmental problem the IPA wants to deny (based on her position on such things as the Murray Darling and Global Warming, where no amount of evidence seems to get through to her). Burke probably won’t be like that, so his presence is a two edged sword for them.

  15. conrad
    August 17th, 2005 at 15:34 | #15

    That just isn’t true Fyodor. Calibrating models on data sets often leaves huge amounts of variance unexplained, particularily if the datasets are ridiculously complex and the amount of parameters in your model is few. Thus there is no guarantee your model can fit historical data at all, unless you use a zillion parameters and can somehow work out how to optimize them all (which I doubt can be done easily with climate models that take presumably take ages to test on a single parameter set).

    In addition, if models weren’t useful at predicting future trends in circumstances with some predictability (like when will El nino come ? will we get lower rainfall this year ? etc.), we may as well give up on them right now. Since no-one seems to want to do that, I presume the consensus is that they do have some ability to predict future climate changes.

  16. August 17th, 2005 at 16:04 | #16

    No, Conrad, such multivariate data-fitting happens all the time, in all sorts of industries and scenarios. It’s an innate problem for any model that makes simplifying assumptions about complex systems. Good modellers know it’s a risk and acknowledge the limitations of the models they produce.

    However, even crap models are better than nothing, and that is why we use them. Unfortunately, people like yourself seem to assume that because we are using models we can predict the future. That’s grossly naive and extremely dangerous thinking.

  17. jquiggin
    August 17th, 2005 at 17:42 | #17

    Fyodor, as the post suggests, most of these models were reasonably well-developed before 1997. They predicted warming, whereas the obvious null hypotheses predicted either no change or a return to the long-term mean (that is, cooling).

    As you say, the big test is predicting the future. On this score, the models have been right and the sceptics (to the extent they’ve been willing to make testable predictions) wrong. A notable example is the late John Daly, who predicted a sharp drop in global temperatures right about now.

  18. August 17th, 2005 at 18:20 | #18

    What were the underlying assumptions in John Daly’s models, that were suggestive that global temperatures would be dopping?

    What factor does the location of weather/temperature stations play in the various models. For example, a gauge that was placed on the corner of Bourke St and Swanston street in Melbourne 30 years ago may have registered more ‘heat’ owing to vehicle traffic; but since the volume of vehicles has fallen dramatically owing to the pedestrianisation of that interseaction, so ‘heat’ emitted would have been significantly reduced.

  19. conrad
    August 17th, 2005 at 19:04 | #19

    Fyodor, I don’t disagree with you that all models have limitations and that in some areas the predictive power of some of the models is low. However, I’m not sure why you think using models to try and predict future behavior is naive and dangerous. Even if the models could only explain a small amount of the data, they would still be worthwhile in many areas.

    What other method do you think people should use to plan for the future ? Sit and wait until potentially catostrophic event occurs ?

  20. August 17th, 2005 at 20:02 | #20

    The climate models are not supposed to be 100% accurate and no climate scientist would expect them to be. Some of the large GCM’s that take into account the ocean and run on supercomputers get the closest.

    Computer models are tools only. The allow scientists to conduct experiments on a system where various parameters can be changed to see what happens. Conclusions are then drawn as to what might happen in the real system. Different models are best at investigating different things and even quite simple ones can yield information.

    The problem is that we do not have a spare planet to experiment on so computers are the best we have. No wait – we ARE experimenting on a planet – the planet Earth. We are increasing the atmospheric CO2 concentration and seeing what will happen. Just to make sure the CO2 rises really quickly we are deforesting the planet as well. Pity we do not know the result and are flying blind.

  21. August 17th, 2005 at 23:37 | #21

    John,

    I can’t see that what you have posted above is consistent with what you wrote as a comment on 22nd April at http://johnquiggin.com/index.php/archives/2005/04/21/a-request-for-help/#comments .

    Following is what you wrote in April before it was realized that the satelite data was wrong (i.e. when the data was showing that the troposphere was not warming as much as the earth’s surface):

    Jennifer, I’m not an expert, but here’s my potted summary.

    1. GW models generally predict that the troposphere should warm at the same rate as the surface or even faster.

    2. The first attempts at tracking satellite data, by Christy and Spencer, showed a cooling trend, which caused a lot of excitement particularly among GW sceptics.

    3. Since then, there have been a lot of criticisms of the Christy measurements, new data and alternative analyses.

    4. As a result, all groups now agree that the satellite data shows a warming trend.

    5. Some (e.g. Fu) find a trend very close to that measured at the surface, while others, most notably Christy and Spencer, find a slower warming trend.

    6. Over the same period, the measured warming trend at the surface has become clearer and lots of potential sources of error, such as urban heat islands, have been checked and corrected for, or found to be unimportant.

    7. Based on the history above, while there are still unresolved questions, the satellite data is a very weak reed for GW sceptics. It seems most likely that the true rate of warming is the same, and that the measurement differences will be resolved with an answer close to (but maybe a little bit below) the current surface measurements.

    This article at SEPP is not too bad on the history, though it puts more weight on Christy’s work than is really justified, I think.

  22. August 18th, 2005 at 00:32 | #22

    Sorry, I had to alter the slug for that post as some glitch was preventing comments. The post in question referring to this one is now to be found here.

  23. August 18th, 2005 at 00:35 | #23

    Fyodor Says: August 17th, 2005 at 4:04 pm

    Unfortunately, people like yourself seem to assume that because we are using models we can predict the future. That’s grossly naive and extremely dangerous thinking.

    Why else would anyone use a model, if not to predict the future? Thats what models are for, since they are not just constructed as playthings. Or is Fyodor trying out one of his abysmal puns on the long-suffering readers of this blog?

    We shall just have to be brave about the “extremely dangerous” risks we take when we rely on models to predict the future workings of the world. What with our reckless predictions of the morrows eastern sunrises and who knows what other “naive” beliefs that trail in tow.

    Fyodor’s excessive skepticism is irrational and has a psychological, rather than epistemological, basis. He seems compelled to attempt to reverse conventional wisdom or common sense on a range of disparate subjects.

    He does not believe that Australian political culture, over the past decade, has become more conservative. Although Keating is still on the nose, the DEMs are a spent force and John Howard is now controlling the Senate.

    He does not believe that elements within the TNI encouraged jihadist-style sectarianism in the ETIMOR conflict. Although numerous eye witness report to the contrary.

    He does not believe that racial classifications show real genetic diversity and heredity in psychological traits. Although the evidence of HGP data and the analysis socio-bio scientists shows that Darwinian evolution theory is applicable to the explanation of human bio-diverse behaviour.

    He does not believe that the Holy Wars that began around the turn of the first millenium were, at least in part, caused by Muslim aggression. Although Muslims overran, in succession, Christian lands in Mesopotamia, (Arabs), Iberia (Moors) and Byzantine (Turks).

    And now, apparently, he does not believe in the reality of global warming. Although the experts in the field have repeatedly beaten him over the head and shoulders with an improved hockey stick.

    Fyodor’s epistemology is a good example of the cult of irrationalism that plagues those hooked on post-Popperian “critical rationalism”. David Stove has a good account of the essential frivolity of the hyper-critical attitude (in place of Popper’s name I have substituted Fyodor, otherwise the argument is perfectly transferrable):

    There is another feature of

    [Fyodor's] writings… This is, their levity or enfant-terriblisme.

    The simple and sufficient proof of [Fyodor's] levity is this: that he is always saying `daring’ things that he does not mean. For example he says, and says, as we have seen, with all possible emphasis, that there is no good reason to believe any scientific theory. But he is not in earnest.

    He does not really believe that there is no good reason to believe…In other words, [Fyodor's] daring irrationalist sallies are meant to be tried, like a baron under Magna Carta, only by a jury of his peers, and for the same reason: the other people might not understand.

    The levity of [Fyodor] and his followers concerning science bears a marked analogy, therefore, to a species of political levity which is excessively familiar: what Kipling called “making mock of uniforms that guard you while you sleep”. [ritualistic libertarianism!] For who are the pet aversion of [Fyodorians], as policemen are of parlor-pinks? Why, ordinary flesh-and-blood scientists, of course!

    Any contact with living scientists … can be relied on to bring him out in fury of what we may call `criticism-ism’. Scientists, he finds to his horror, are dogmatic, uncritical, authoritarian, etc., etc. So they are, of course.

    It is the frivolous elevation of the `critical attitude’ into a categorical imperative of intellectual life, which has been at once the most influential and the most mischievous aspect of [Fyodor's] philosophy of science.

    Even in its non-extreme forms, however, the apotheosis of the critical attitude has had, as its principal effect, simply this: to fortify millions of ignorant graduates and undergraduates in the belief, to which they are already only too firmly wedded by other causes, that the adversary posture is all, and that intellectual life consists in “directionless quibble”.

    Can we not see, in Fyodor’s frequent bursts of small-arms fire against the big guns, this self same combination of frivolous levity and nihilistic skepticism?

    Stove sees an unresolved psychological complex behind this compulsion:

    A Freudian might see, or imagine he sees, something more than adolescent revolt, something actually obsessive, in Popper’s compulsion to reverse things.

    I believe that the solution the “Fyodor problem” lies within his twisted psyche. When someone appears to be too disconnected to reality physicians usually characterise them as mad, bad or sad.

    I do not think Fyodor is mad. His arguments per se are intelligent and sane enough to merit consideration, if not condonation, by participants on this blog.

    I do not think Fyodor is bad. He appears to believe in some slightly watered down version of libertarianism. It is a stage many people go through in their undergraduate years, by no means a hanging offence, although it is pathetic at his age.

    I do think Fyodor is sad. His frivolous contrarianism, that takes skepticism to the verge of solipsism, constitutes a cry for help. He needs someone significant to care for him. Someone out there, please, give him the love he so desperately craves, if only to get him off the backs of the knowledge seekers and acquirers. I just don’t have it in me.

  24. August 18th, 2005 at 00:35 | #24

    Jennifer, in April John wrote that “It seems most likely that the true rate of warming is the same, and that the measurement differences will be resolved with an answer close to (but maybe a little bit below) the current surface measurements.” And now his prediction has come true.

    What do you think is the inconsistency?

  25. Nabakov
    August 18th, 2005 at 02:16 | #25

    Shorter Strocchi: Fyodor is pissing me off big time.

  26. August 18th, 2005 at 07:37 | #26

    You know you’ve hit the Jackpot when he goes over two pages of text. The best part of this is he only had to see my name to lose the rag.

    Come in, spinner!

    I’ll return to the usual programme once I’ve stopped laughing.

  27. August 18th, 2005 at 10:01 | #27

    Fyodor, as the post suggests, most of these models were reasonably well-developed before 1997. They predicted warming, whereas the obvious null hypotheses predicted either no change or a return to the long-term mean (that is, cooling).

    As you say, the big test is predicting the future. On this score, the models have been right and the sceptics (to the extent they’ve been willing to make testable predictions) wrong. A notable example is the late John Daly, who predicted a sharp drop in global temperatures right about now.

    Hang on, JQ. Are you seriously suggesting that confirmation of a warming trend of, say, 0.12C to 0.19C for a highly volatile variable over an 8 year period (1997-2005) validates the predictive power of current models? I suggest to you that this is nowhere near conclusive proof of any such thing. The Earth has warmed and cooled by many multiples of this amount several times over just the last millenium, and we simply do not know whether existing models’ projections of sustained warming over a 50 to 100 year period are reliable.

    All that has been confirmed (and this being science, not logic, only contingently so) is that the discrepancy between surface and satellite temperature observations appear to have been resolved in favour of the surface data showing warming. As I stated in my first comment, this is not news. I think there is little room to doubt that the Earth has been warming in recent decades. Why this is so, whether this trend continues and why, are the current points of contention.

  28. August 18th, 2005 at 10:09 | #28

    Fyodor, I don’t disagree with you that all models have limitations and that in some areas the predictive power of some of the models is low. However, I’m not sure why you think using models to try and predict future behavior is naive and dangerous. Even if the models could only explain a small amount of the data, they would still be worthwhile in many areas.

    What other method do you think people should use to plan for the future ? Sit and wait until potentially catostrophic event occurs?

    Conrad (and Ender, too), just to clarify, I do not believe that building and using models is naive and dangerous. My view is that using the output from these models uncritically, without explicit acceptance of their limitations, is naive and dangerous.

    I actually believe that models and simulations are one of the few real tools we have to help us understand current and historical trends, and to make projections for the future. I similarly believe that we’re not there yet, and more research is required before we can truly say that we understand what is going on with global temperature, or forecast with any accuracy.

    Of course, this position makes me an anti-science Creationist, but apparently scepticism isn’t “scientific” any more.

  29. August 18th, 2005 at 10:22 | #29

    Fydor – I absolutely agree with you. Using the output of these models uncritically is wrong. In all cases the investigators using the models will publish at the start of any paper the limitations of the model that they are using along with the assumptions used. These limitations and the acceptance of them by the scientists are not generally communicated to the general public.

    No-one can predict the future. What is not generally understood and often get confused is the climate scientists have never claimed that they can predict the future. They have given us, using the tools at their disposal, their best guess at what might happen.

    It is up to us to decide on what risks we are prepared to take. Right now we are ‘betting the farm’ on there being no climate change or risk to our society. Only time will tell if this gamble is right.

  30. wilful
    August 18th, 2005 at 10:32 | #30

    I’m still hung up on where the inconsistency is between PrQ’s April and current statements… I simply can’t see it.

  31. frankis
    August 18th, 2005 at 13:36 | #31

    You have me beat as well Jennifer, but thanks for reprising John’s synopsis from April which to me still reads very well indeed. I think you may be misreading something, somewhere; would you be more specific about what you have in mind?

  32. Chris O’Neill
    August 18th, 2005 at 14:57 | #32

    The ABC put up the transcript of Don Burke’s Landline interview.

    He says “In other words, there are vast amounts of carbon stored underground – gas, coal, oil. We’re taking that up and we’re dumping it in the easiest place possible – in the atmosphere. If we continue to do that, the world is in deep trouble. It is already in some trouble now, and I think we would be far better off to spend that time and concern working out what we do with all this carbon. We just can’t keep pumping it out into the air. The planet can’t cope with that.”

    Yes, could be a double edged sword for the IPA. Either that or they’re changing their position. Certainly makes a difference from Marohasy.

    Also, Fyodor doesn’t realize or ignored the fact that the warming trend has been confirmed for much longer than 8 years. If the satellite record now confirms the surface record then the rapid warming trend has been confirmed from at least 1980 to 2005. A regression from 1980 gives the world about 0.4 degrees C hotter than 1980. McKitrick in his paper relies on the assumption that the satellite record shows cooling since 1980 to reach the conclusion that we are still cooler than the Medieval warm period. Since this assumption has now been proven to be false we can use even his reconstruction of pre-1980 temperatures and the satellite confirmed temperatures since then to conclude that it is now warmer than any time in the last 1000 years.

    Even McKitrick would be forced to agree that the world is now warmer than at any other time in the last 1000 years. That is news.

  33. August 18th, 2005 at 15:06 | #33

    I’ve said it before, the simplest way to sequester carbon is to grow and bulldoze renewable wood chip timber, make charcoal from it, and bury it in landfill or – better – bulldoze it into rivers and creeks and thence let it pass into the ocean depths. This carbon is non-biodegradable and will only be recycled by geological processes, since it does not get exposed to weathering by ultraviolet light acting on water (the effect that causes sun bleaching by creating trace hydrogen peroxide). Even the processing can be done using the wood chips as fuel, e.g. with gas producers.

  34. Chris O’Neill
    August 18th, 2005 at 15:07 | #34

    That link to McKitrick’s paper should be here.

  35. August 18th, 2005 at 15:21 | #35

    Also, Fyodor doesn’t realize or ignored the fact that the warming trend has been confirmed for much longer than 8 years. If the satellite record now confirms the surface record then the rapid warming trend has been confirmed from at least 1980 to 2005. A regression from 1980 gives the world about 0.4 degrees C hotter than 1980. McKitrick in his paper relies on the assumption that the satellite record shows cooling since 1980 to reach the conclusion that we are still cooler than the Medieval warm period. Since this assumption has now been proven to be false we can use even his reconstruction of pre-1980 temperatures and the satellite confirmed temperatures since then to conclude that it is now warmer than any time in the last 1000 years.

    Even McKitrick would be forced to agree that the world is now warmer than at any other time in the last 1000 years. That is news.

    Chris, the eight year time frame I used refers to JQ’s assertion that we’ve had decent climate models since 1997. Not surprisingly, many of those predicted warming from 1950 to, oh, about 1997. Can you guess how they predicted global temperature retrospectively?

    And, no, we can’t be certain about temperatures in the Medieval warm period, because we don’t have reliable data. We do, however, have reliable historical records suggesting that vineyards in England and abundant pastureland in Greenland during that period weren’t fabrications. The Earth’s temperature appears to have varied significantly during historical and pre-historic periods, without any man-made interference.

  36. jquiggin
    August 18th, 2005 at 16:45 | #36

    Fyodor, there’s a big shift from your initial point

    it’s called “data-fitting�, i.e. calibrating a model to replicate known historical trends. This is not necessarily helpful in predicting unknown future trends.

    to your current position that 8-10 years of successful prediction is not enough to claim success.

    If we had infinite time to make up our minds, then we could wait as long as we liked to validate the models. As it as, we have on the one hand, models based on well-validated physical principles and a substantial amount of confirming evidence and on the other hand, the arguments put up by the likes of Ross McKitrick and John Daly. Given that we have to make some choices now, which do you suggest is more credible?

  37. wilful
    August 18th, 2005 at 16:45 | #37

    I found the McKitrick paper interesting, but only useful when read at the same time as this paper.

  38. August 18th, 2005 at 17:15 | #38

    JQ,

    There’s no inconsistency. The models have been fitted to a posteriori data. You say they’ve been around since 1997, so that means they’ve been able to test a priori assumptions about the future over a period of only eight years. This is inconsequential given the size and scope of the system being modelled.

    If we had infinite time to make up our minds, then we could wait as long as we liked to validate the models. As it as, we have on the one hand, models based on well-validated physical principles and a substantial amount of confirming evidence and on the other hand, the arguments put up by the likes of Ross McKitrick and John Daly. Given that we have to make some choices now, which do you suggest is more credible?

    Why do you reach for absolutes? We don’t need infinite time to improve the models – they’re improving all the time. The models reflect current knowledge and the biases of their creators. This doesn’t make them useless, but it does mean they have about as much predictive power as the people building them, i.e. SFA.

    What do I think we should do? Nothing, at the moment. It’s always an option, and usually a good one until you know what you’re playing with.

  39. frankis
    August 18th, 2005 at 18:13 | #39

    It’s too easy, Fyodor – your comment “… we should do? Nothing, at the moment. It’s always an option, and usually a good one until you know what you’re playing with” clearly is best suited to justifying an immediate cessation of the dumping of gigatonnes per annum of CO2 into the atmosphere of the only known living planet in the universe. There isn’t any scientific doubt, modeled or otherwise, that this should be expected to have potentially bad consequences for global climate and ocean chemistry at least.

    Now for other reasons you’ll agree we can’t just do that (reduce our emissions to zero) yet your argument such as it is above is no good at all for your implied, preferred option of a “business as usual” toying with our atmosphere.

  40. hermit
    August 18th, 2005 at 18:35 | #40

    PML I doubt the Black Sludge method would work. The fuel for machinery requirement would use perhaps more carbon than the volatiles could provide, and the charcoal would initially float and make a grotesque slick. Charcoal also binds nutrients such as phosphorus which would have to be given to the replacement trees.

  41. frankis
    August 18th, 2005 at 19:12 | #41

    Jennifer, I’ve just seen at your blog that you quote Bill Kininmonth as having at some time told you “Greenhouse gases in the troposphere cause the troposphere to cool …” http://www.jennifermarohasy.com/blog/archives/000793.html
    It may be that bloopers like this (let’s face it, it’s a prima facie absurd suggestion in these times of daily discussion of the “greenhouse effect”) from Kininmonth have had something to do with your present state of mild confusion on the issues.

    In reality, “Increases in the concentrations of greenhouse gases reduce the efficiency with which the surface of the Earth radiates heat to space: More outgoing terrestrial radiation from the surface is absorbed by the atmosphere and is emitted at higher altitudes and colder temperatures. This process results in positive radiative forcing, which tends to warm the lower atmosphere and the surface. This radiative forcing is the enhanced greenhouse effect …” from http://www.grida.no/climate/ipcc/aviation/066.htm

    [btw I wouldn't have drawn attention to just a typo; Kininmonth goes on in Jennifer's quoted text to do further damage to both common sense and science]

  42. jquiggin
    August 18th, 2005 at 19:33 | #42

    Fyodor, you’ve gone from making a substantive (but no longer sustainable) critique to a position that, no matter what the evidence (within the limits of what can be feasibly collected in the time available to us) you’re not going to be convinced to abandon your own policy preferences. This is pretty disappointing.

  43. conrad
    August 18th, 2005 at 20:01 | #43

    Fyodor,

    the problem with doing nothing is that the problem never sits still, which might be rather worrisome, especially if you happen to live in Bangladesh or some low-lying island, and particularily given that there are likely to be no cold-turkey solutions. Looking at the last 20 years shows that you can get a reasonable amount of temperature variation in compartively short times (a time shorter than that needed to provide evidence to convince the tobacco industry that smoking is harmful, for instance).

    http://en.wikipedia.org/wiki/Image:Instrumental_Temperature_Record.png

    Thus hanging around and waiting for completely irrefutable evidence might be a poor tradeoff given the potential harm that might occur

  44. Fyodor
    August 18th, 2005 at 21:02 | #44

    Fyodor, you’ve gone from making a substantive (but no longer sustainable) critique to a position that, no matter what the evidence (within the limits of what can be feasibly collected in the time available to us) you’re not going to be convinced to abandon your own policy preferences.

    Not at all, JQ. Indeed, you’re lurching from one strawman to another. Your supposed deadline about the “time available to us” is redolent of the kind of hysteria that is precisely antithetic to the proper use of science. We’ve made tremendous advances in the climate sciences over the last decade, and I’m hopeful we’ll learn even more in the coming decade. Maybe global warming is anthropogenic, maybe it’s not. I’m open to new evidence; you’ve already made up your mind. Tell me who’s the one operating from belief rather than knowledge.

    Your supposed “disappointment” is disingenuous. We’ve played out this argument before and no doubt we’ll do it again.

  45. August 18th, 2005 at 21:50 | #45

    Fyodor – opposing action on climate change because we do not have enough information is basically wrong. It is not about who is right and wrong. It is about risk. The people who make money from assessing risk, the insurance industry, is already moving and urging action on AGW as they are already seeing the effects of climate change in increased payouts.

    What JQ is alluding to is not hysteria. It is an assesment by scientists that we have a rapidly closing window to reduce the effects of AGW. After this time has passed it really does not matter a pair of fetid dingo’s kidneys what we do as the die will be cast and we will have to live with the effects whatever they are.

  46. SJ
    August 18th, 2005 at 22:42 | #46

    P.M.Lawrence Says: August 18th, 2005 at 3:06 pm

    I’ve said it before, the simplest way to sequester carbon is to grow and bulldoze renewable wood chip timber, make charcoal from it, and bury it in landfill or – better – bulldoze it into rivers and creeks and thence let it pass into the ocean depths. This carbon is non-biodegradable and will only be recycled by geological processes, since it does not get exposed to weathering by ultraviolet light acting on water (the effect that causes sun bleaching by creating trace hydrogen peroxide). Even the processing can be done using the wood chips as fuel, e.g. with gas producers.

    hermit Says: August 18th, 2005 at 6:35 pm

    PML I doubt the Black Sludge method would work. The fuel for machinery requirement would use perhaps more carbon than the volatiles could provide, and the charcoal would initially float and make a grotesque slick. Charcoal also binds nutrients such as phosphorus which would have to be given to the replacement trees.

    Isn’t there something about this proposal that strikes you two as a bit odd? Something beyond the simple mechanics and chemistry of it?

    Something along the lines of it being simpler to not dig up and burn an equivalent amout of coal?

  47. Chris O’Neill
    August 19th, 2005 at 00:34 | #47

    Fyodor was being very misleading in asserting that “The Earth has warmed and cooled by ‘many’ multiples of this amount several times over just the last millenium”. “this amount” referring to “0.12C to 0.19C .. over an 8 year period”. The issue with the satellite data is not just about confirming models, it is about confirming surface measurements before you even start thinking about models. As you can see from McKitrick’s paper, he didn’t believe that there’s been any warming since 1980 because the satellite derived temperatures didn’t confirm the surface measurements. Since there is now confirmation, one of McKitrick’s major supporting data has been knocked out.

    I didn’t notice any reference from Fyodor supporting how much he thinks the earth has warmed and cooled in the last millenium. Unless he can find a paper that supports his assertion better, I’ll go by figure 8 in McKitrick’s paper which says the biggest change in the last millenium was a 0.5 degree C fall in the 15th century. I suppose 0.5 is “many multiples” of 0.12 to 0.19 (just!) but 0.12 to 0.19 degrees C is just the per decade warming since 1980, not the total warming. The total warming is around 0.4 degrees C. You can’t quite say 0.5 is “many multiples” of 0.4 can you?

    The original issue of this thread is the effect of the satellite data now confirming the surface data. This may not affect whether someone believes climate models or not. But the one thing it does affect is whether people such as McKitrick believe that there has been substantial warming since 1980. McKitrick’s argument that there hasn’t been has been destroyed.

    So the issue is now can we all agree that the earth is warming seriously, so much so that it’s the warmest in a thousand years, regardless of the cause? Can we now move on to arguing about why the warming is occuring and stop using time arguing about whether serious warming is actually occuring?

  48. August 19th, 2005 at 00:39 | #48

    FyodorSays: August 18th, 2005 at 7:37 am

    I’ll return to the usual programme once I’ve stopped laughing.

    I got to say that it is I who have been the one splitting my sides laughing, following the richly amusing Fyodor-takes-on-all-comers-and-gets-made-into-mincemeat series. Its rather like watching that episode of Daffy Duck where DD tries to call the shots to his animator as the latter slowly erases him from the picture. Or, as Stove remarked in another context, seeing the absurd bluff posture of a frog puffing itself up, in a futile attempt to intimidate a man. Who does he think he is trying to kid?

    Apparently Fyodor thinks it is some kind of wicked methodological sin to construct models on the basis of a set data set, then tweak the models to correct the errors so that the models fit the data in later runs. He is confusing two different activities: tweaking models to fit disparate data and “cooking data” to fit a preconceived model. The latter procedure is the improper activity. But revising the formulation of disparate data sets to reconcile them with an overall predictive model is an example of the former procedure, and is perfectly proper.

    Fyodor is not content to just cast doubt on global warming. He wants to also question the very idea of reliable large scale modelling of complex events. No doubt there are pitfalls in that activity. He is really saying that complex macro-prediction is Mission Impossible, at least for the forseeable future. Since we cant know everything we can never do anything.

    If we were to follow Fyodorian philosophy we would be forever running back and forth between the models and the data without ever running a proper simulation or taking action on the basis of working knowledge. It is “directionless quibble” with a vengance.

    As Stove predicted the Fyodor-types are not satisifed with challenging this or that scientific theory – it is the very methods of practical science that they are going after. This is because they are fundamentally bored with the inevitable imperfections of natural science and social technology, preferring to kick over the traces rather than put their shoulder to the wheel.

    Scientific work is mostly the rather tedious business of data-crunching, which is bound to get in the way of the fun of tearing down idols. But Fyodor is not after working knowledge, like the girls in the song he “just wanna have fun”.

    This mischief is innocent enough in itself. But Fyodor should not pretend to be some kind of scientific or scholarly expert into the bargain.

    Fyodor Says: August 18th, 2005 at 10:09 am

    just to clarify, I do not believe that building and using models is naive and dangerous. My view is that using the output from these models uncritically, without explicit acceptance of their limitations, is naive and dangerous.

    I actually believe that models and simulations are one of the few real tools we have to help us understand current and historical trends, and to make projections for the future.

    So, “just to clarify”, Fyodor does believe in building models but he doesnt believe in using models. Apart from being a most undignified back-pedal this revised position is the frivolous epistemology of the perpetual post-graduate student, not that of a working sci-techhie or a concerned statesman.

    This kind of criticism is an example of what Stove, in another context, calls “cognitive Calvinism” – our models are bad because we, poor forked creatures, made them ourselves with mere facts grubbed from the mysterious and mutable world. Its too early to tell, we have to wait until the end of time! Cognitive Calvinism again, Stove was right on the mark.

    jquiggin Says: August 18th, 2005 at 4:45 pm

    If we had infinite time to make up our minds, then we could wait as long as we liked to validate the models.

    It is striking that Pr Q uses the “infinite time” construction which independently fits Stoves “cognitive Calivinist” coinage. Great minds think alike, especially when slighting lesser ones.

    Pr Q then shows that Fyodor’s position starts to develop contradictory stress fractures under pressure.

    jquiggin Says: August 18th, 2005 at 4:45 pm

    Fyodor, there’s a big shift from your initial point [that the models are invalidly specified] to your current position [there has not been enough time to properly assess the models]

    Most debaters, with a shred of self-knowledge and respect for truth, would have thrown in the towel at this point. But not Fyodor, who keeps throwing wild haymakers at thin air.

    Fyodor Says: August 18th, 2005 at 5:15 pm

    There’s no inconsistency. The models have been fitted to a posteriori data.

    Phew, thats a relief! Fancy if the models had been fitted to a priori data ie made up – then the modellers would really be for the drop.

    Finally even Pr Q, who has shown the patience of a saint up till this time, gives up in despair.
    jquiggin Says: August 18th, 2005 at 7:33 pm

    .no matter what the evidence…you’re not going to be convinced to abandon your own policy preferences. This is pretty disappointing..

    Actually it is pretty much as I expected. Fyodor never admits he is wrong, no matter how compelling the contrary evidence (see the above comment for the syllabus of his uncorrected errors). He is constitutionally incapable of subjective humility, no matter how much objective humiliation he actually suffers. That is pathetic, not disappointing.

    It is also no accident that Fyodor’s skeptical-cum-solipsistic philosophy meshes nicely with his wishy-washy brand of do-nothing “libertarian” policy preferences. (More properly known as proprietarianism, since property rights, rather than protecting the life and liberty of the citizen, are the obscure object of his desire.)

    Fyodor applied the same kind of ritualistic libertarianism (read legalism) in his strictures against anti-terror legislation. But authorities gave violent ratbags a free pass in the free-swinging good old days prior to 911 and Baliand and for our troubles we got sucker punched. Or is this dredging up that unpleasant past another example of me “cooking the data” to fit my rotten authoritarian political model?

    Some advice for Fyodor. He is not stupid and he is entertaining in his own way. But he is not always right and has an unpleasant habit of not suffering his own follies gracefully. The breezy self-assurance he displays in his sweeping generalisations quickly degenerates into bombastic arrogance when a competent scholar points out his errors.

    But he is trading punches with the pros here and its clear that he is out of his league, in over his head an way out of his depth. He needs to re-learn the old lesson that when you are in a hole the first thing to do is stop digging.

  49. Chris O’Neill
    August 19th, 2005 at 00:58 | #49

    If you’re going to make charcoal from forestry, might it be better to use the charcoal to replace the usage of coal and other fossil fuels and thus leave the fossil fuel carbon in the ground rather than replacing it? Is there some economic or other argument for this?

  50. hermit
    August 19th, 2005 at 07:36 | #50

    We seem to have strayed from the topic of weather balloon readings but some big issues have emerged. I agree that there may be a psychological barrier to alternative fuels based on coal, shale or crops such as trees. When an extraordinary amount of visible effort is needed to keep each car on the road people will feel uncomfortable. On the other hand petroleum is like drawing blood; you get an energy rich liquid through pinpricks on the Earth’s surface, not huge quarries or hectares of forest. However if you add the requirement of greenhouse neutrality then biofuels win over oil shale and coal . Since even that is distasteful to some the final option seems to be using less fuel period.

  51. August 19th, 2005 at 07:48 | #51

    Ender,

    We’ve also had this argument before – at Club Troppo, I believe. I think you also made the same points last time:

    Insurance companies think global warming is a problem – yes, but their motives aren’t exactly pure: they get to charge more for bearing risk if the perception of risk increases.

    Decision-making under stress – I’m bored of this one: “we have a rapidly closing window to reduce the effects of AGW. After this time has passed it really does not matter a pair of fetid dingo’s kidneys what we do as the die will be cast and we will have to live with the effects whatever they are.” The problems here are that:

    1) We don’t know whether observed GW is anthropogenic or not;
    2) We don’t know what the “window” for decsion-making is; and
    3) We don’t really know what the effects of AGW will be, if it occurs.

    Faced with that magnitude of uncertainty, I propose the logical course of action is more research until we can answer these questions.

  52. Mark Hadfield
    August 19th, 2005 at 07:55 | #52

    I’m still stuck on Fyodor’s initial assertion: “That the models fit historical data is trivial and expectedâ€?. The subsequent discussion has not clarified what he actually meant by that. People have talked about “data-fitting”, “prediction” and “model limitations” in very non-specific terms. And references to “skeptical-cum-solipsistic philosophy” and “wishy-washy brand of do-nothing “libertarianâ€? policy preferences” don’t advance the discussion in this particular area. (Geat fun, though. Keep it up.)

    Now, I’ve been aware of global climate modelling for some time (I work in smaller-scale ocean modelling myself). I know something about the structure of the climate models and the processes they represent. Over the last decade or two I have heard conference talks about simulating “present” climate (though that’s a moving target), pre-industrial climate, palaeoclimate (eg Last Glacial Maximum) and climate sensitivity. During this time there has clearly been a process of iterative development (simulate, validate, improve) that you might, at a stretch, call data fitting. (But Fyodor this has not been trivial. That was the word that first attracted my attention. I would call it heroic.)

    In recent times there have been several exercises in which a model, resulting from the above iterative development, has been run for the 20th century, more or less, subject to time series of various “forcings”. These time series have, as far as I know, been derived *a priori*. They’re subject ot uncertainty, of course, but they’re best estimates from available knowledge. The model has been run several times on the same forcings with randomly different initial conditions, generating an ensemble of different “predictions”. (Yes, I know they’re not actual predictions of the future.)

    Two things have surprised me about the results of these exercises: 1) for a an integral quantity like global mean surface temperature, the scatter between the members of the enseble has been rather small; 2) the mean of the ensemble has tracked the observed global mean surface temperature very well. But don’t take my word for it, follow the links in this RealClimate post:

    http://www.realclimate.org/index.php?p=100

    The people who do this stuff are aware that their forcing time series are uncertain and try various combinations and perturbations. They conclude that some of the temporal variations are due to the natural forcings (volcanoes, solar) and some due to the anthropogenic ones (tropospheric aerosols, greenhouse gases) but you need both to get a good match.

    Now I can see that dishonest modellers could pervert this process, by choosing the forcings to get the results they want. But they appear to be open about what they have done and I am not aware of anyone having proposed forcing time series that are substantially different *and* plausible. (Eg you could propose that solar forcing has risen in the second half of the 20th century, but as I understand it there is no a priori reason to believe this has happened and recent measurements strongly indicate that it hasn’t happened.)

    So Fyodor, the models (iteratively develpped or fitted as you will) have been driven by a priori forcing time series and have produced surprisingly good hindcasts of the global mean temperature over the last century or so. What problem do you have with that?

  53. August 19th, 2005 at 08:11 | #53

    Chris,

    Your first paragraph is confusing, but your I agree with your concluding point, i.e. it looks like we have resolved the surface-satellite discrepancy.

    Re: your second paragraph, no, I don’t have the data to hand (and can’t be bothered to look for it) and, given we do not have accurate temperature readings earlier than the 20th century (if that), the actual magnitude of temperature changes can only be known approximately. We do know, however, the direction of temperature changes, which varied, and we do know the changes were significant enough to be noticed by historical sources, and to be evident in tree rings, ice core samples etc. It’s also worth pointing out that in just the past fifity years we have seen increases and decreases in temperature. The Earth’s surface temperature clearly changes without human interference, and we don’t know why. Despite this, a lot of people (let’s call it a “consensus”) are certain that recent warming is attributable to human action.

    Re: your third paragraph, reread JQ’s initial comments. The title for this thread is “Climate change modellers vindicated”, not “Surface data vindicated”, so I’m not constructing a strawman here.

    Re: your concluding paragraph, your assertion that the Earth is hotter now than it’s been in the past 1,000 years is contentious, to say the least. I agree with your sentiment, though: the data on recent warming looks solid, so we really should spend more time asking why the Earth has warmed. Unless you’ve got all the answers already, of course, in which case I’m all ears.

  54. August 19th, 2005 at 08:18 | #54

    Plagiarised Nabsy on shorter Strocchi: Fyodor is really pissing me off!

    I hope it didn’t take you a whole day to come up with that exceedingly concise and pithy contribution to the subject of this thread.

  55. August 19th, 2005 at 08:32 | #55

    Mark Hadfield,

    By the statement, “That the models fit historical data is trivial and expected.� I meant that it is not surprising that climate models developed to simulate climate change tend to match historical data, because their output is usually tested for a posteriori predictive power against historical trends.

    The risk in the model building and testing process is that the model builder works through so many iterations to “fit” the model to the historical data, that they lose the rigour of the science used in determining the key variables and the structure of the model, thereby producing a model that works really well at predicting the past, but may be lousy at predicting the future.

    I hope that clarified my position for you. Can you now clarify something for me? Can you elaborate on the following statement, as I don’t understand what you mean.

    In recent times there have been several exercises in which a model, resulting from the above iterative development, has been run for the 20th century, more or less, subject to time series of various “forcings�. These time series have, as far as I know, been derived a priori.

  56. Mark Hadfield
    August 19th, 2005 at 09:15 | #56

    Hi again, Fyodor

    How do you do those verical-line quote thingies? I am new to blog discussions.

    Quoting your paragraph:

    ***

    By the statement, “That the models fit historical data is trivial and expected.� I meant that it is not surprising that climate models developed to simulate climate change tend to match historical data, because their output is usually tested for a posteriori predictive power against historical trends.

    ***

    Aha! Now we’re getting somewhere. It is my understanding that the models have not been tuned to fit historical trends. They have been tuned (iteratively developed) to represent various aspects of equilibrium climate accurately *then* run with historical trends in forcing *then* the trends they produce in global mean surface temperature have been validated against the instrumential record. But I have a lot of reading to do about this.

    Now my paragraph that you don’t understand

    ***

    In recent times there have been several exercises in which a model, resulting from the above iterative development, has been run for the 20th century, more or less, subject to time series of various “forcings�. These time series have, as far as I know, been derived a priori.

    ***

    I’m talking about the GISS hindcast for 1880-2000 described in these links

    http://www.realclimate.org/index.php?p=100
    http://www.realclimate.org/index.php?p=148

    A few years ago I read about something similar by the UK Hadley Centre people.

  57. August 19th, 2005 at 09:27 | #57

    Howdy to you too, Mark,

    There’s bound to be someone around who can explain this more elegantly, but the quote thingies are done by opening an arrow quote, typing “blockquote”, closing with an arrow quote, pasting in the text you want to quote, opening another arrow-quote, forward slash, “blockquote”, then closing arrow quote.

    Christ this is a clumsy explanation, but it should look like a pointier version of this:

    (blockquote)text(/blockquote)

    In case you’re wondering, I don’t know how to type in the arrow-quote without actually launching its function. Hope that helps.

    Thanks for the links – I’ll have a read.

  58. August 19th, 2005 at 09:57 | #58

    Mark,

    I’ve read the links you’ve provided, and I think you’ve confused the meaning of a priori in your original statement. Through many iterations the models the links refer to have been used to, as you say, hindcast (a posteriori) the historical experience, but the track record on actual (i.e. truly a priori) prediction remains extremely limited. If we take JQ’s “start” point of 1997, models have only been forecasting (as opposed to hindcasting) for around eight years. As I said previously, this is not a long time frame for testing the predictive validity of these models.

  59. wilful
    August 19th, 2005 at 10:03 | #59

    carry on…

  60. wilful
    August 19th, 2005 at 10:05 | #60

    wordpress sucks.

    How about some hotlinks to the basic functions, near the comments box?

    I agree with your sentiment, though: the data on recent warming looks solid, so we really should spend more time asking why the Earth has warmed. Unless you’ve got all the answers already, of course, in which case I’m all ears.

    Now that’s the clearest thing you’ve said.

  61. Mark Hadfield
    August 19th, 2005 at 10:18 | #61

    Fyodor

    Yeah, you’re probably right about “a priori”. Strictly speaking it means “beforehand”. My point was that the forcing time series were *not* fudged to get the results the modellers wanted. At least I don’t think they were…

    I think you’re setting the bar of “predictive validity” too high. Natural scientists don’t usually have the luxury of running well-controlled experiments. Mankind’s current greenhouse-gas experiment is an interesting one, but even it is imperfect. Luckily, mankind seems intent on applying a really big greenhouse forcing so the signal will probably be visible above the confounding factors.

    Let’s say we had a perfect model. Our forecasts of (say) global mean surface temperature over the next 30 years would still be limited by: uncertainty in projecting greenhouse concentrations; uncertainty about the other forcings; intrinsic variability (but the models suggest that it’s not all that largeif you average over the whole earth for a decade or so).

    Let’s say in 30 years time we do have very good climate models and very good time series for the forcing factors. Let’s say we run a hindcast and find it matches the observations very well. You will still be able to say that it’s only a hindcast and agreement is only to be expected (but please don’t call it “trivial”).

    I don’t think I can contribute much more to this discussion without doing more background reading…

    Cheers.

  62. August 19th, 2005 at 11:30 | #62

    Fyodor:

    “The problems here are that:

    1) We don’t know whether observed GW is anthropogenic or not;”
    Well yes we do however you are in the minority of people that still think that it is not. In the opinion of most scientists in the world Global Warming is anthropogenic.

    “2) We don’t know what the “windowâ€? for decsion-making is; and”
    Again yes we do. If the rate on CO2 was drastically reduced now then the warming could be held to less than 2 degrees. This has been confirmed in a range of scenerio modelling. If you want proof just wait. After this time the CO2 already in the atmosphere will raise the temperature from 5 to 10 degrees and no decrease in CO2 will stop it. The research is quite clear and we have enough information.

    ’3) We don’t really know what the effects of AGW will be, if it occurs.”
    No we don’t – however I have never seen you write that you might be wrong. I have. You do not know that the effects of GW whether it is antropogenic or not will be.

    “Faced with that magnitude of uncertainty, I propose the logical course of action is more research until we can answer these questions.”
    We will only answer these questions when the effects are irreversible. We have enough information to act now. I never said the insurance industry has pure motives – it is affecting their bottom line. They make money from calculating and assessing risk. If you cannot listen to most of the world’s scientists telling you there is a problem then at least listen to the industry that is the best at assessing risk. They are telling us that there is a non-zero risk that the climate will change.

  63. August 19th, 2005 at 11:55 | #63

    Ender,

    1) Opinion is not science.

    2) Reread my previous comments about the limitations of scenario modelling.

    3) You’ve never seen me write that I might be wrong? I have, but for your benefit let me state it again, categorically: I might be wrong.

    We will only answer these questions when the effects are irreversible.

    Conjecture.

    We have enough information to act now.

    Again, opinion is not knowledge. How can you be certain that you have enough information when you don’t know how the Earth’s weather works?

    If you cannot listen to most of the world’s scientists telling you there is a problem then at least listen to the industry that is the best at assessing risk. They are telling us that there is a non-zero risk that the climate will change.

    I’m always listening, and I do follow the progress of the scientists. Do I believe certain scientists’ forecasts for global temperature in 2055? No, I don’t, for many obvious reasons. Do I question the motives of the insurance industry in modelling catastrophe risk? Absolutely. Do I think their views are as tainted as the astroturf outfits JQ regularly chastises? Absolutely. WTF does “…non-zero risk that the climate will change.” mean? History alone tells us that climate will change. That’s not in dispute.

  64. Ros
    August 19th, 2005 at 12:04 | #64

    Some climate sceptics are prepared to put their money where their mouths are.
    http://www.guardian.co.uk/uk_news/story/0,3604,1552092,00.html

  65. Chris O’Neill
    August 19th, 2005 at 14:50 | #65

    I’m sorry if Fyodor is confused by my explanation of how he was misleading but that’s often the way it is when someone is misleading i.e. showing how someone is misleading is often not a trivial process.

    So Fyodor can’t be bothered to look for data to support his bare-faced assertion that “The Earth has warmed and cooled by ‘many’ multiples of this amount several times over just the last milleniumâ€?. It’s all very well waffling on about how past temperatures have produced a record but until you can come up with a backed-up number you’ve made nothing more than an assertion. It’s just my opinion but I don’t think many people are interested in bare-faced assertions by nobodies like Fyodor.

    When I said “the original issue of this thread”, the intended meaning was the issue that motivated this thread (the resolution of the temperature record discrepancy). I don’t see any problem with pointing out a profound consequence of this, even if it’s not the same consequence that Pr Q wrote about.

    I didn’t actually assert that the Earth is hotter now than it’s been in the past 1,000 years. I implied that I thought it was but more importantly I had previously written that a deduction from the surface instrument and satellite records since 1980 and McKitrick’s reconstruction pre-1980 showed this to be true. So what’s Fyodor’s problem with saying the earth’s surface is the warmest it’s been in a thousand years? Does he wan’t to just say we’re 99% certain the earth’s surface is the warmest in a thousand years? i.e. does he have a problem in this context with the way language is often used. I guess usually when people are 99% certain of something they don’t usually bother saying “99% certain”. Or does he think all the climate reconstructions are complete rubbish?

  66. Stephen L
    August 19th, 2005 at 15:02 | #66

    James Annan has made the easiest $10,000 in the history of scientific work. I wonder if those guys are looking for further people to take their money off them.

    That Lindzen wants odds of 50-1 shows just how much confidence he has in his own claims. Effectively he is saying “there is only a 2% chance that I am right, but the world should risk global catastrophe on that basis”. Actually this is not quite fair, if there was some slight warming Lindzen could still reasonably claim to be right, but would lose his money. However, this could be easily settled with a bet of warming of more than a certain amount. I think Lindzen wouldn’t take that either without favourable odds – in other words he knows he is lying, and putting the world in danger in the process.

    Getting back to Ffyodor, let me see if I have summarised the position correctly:

    Thousands of the world’s finest minds have spent decades trying to model the global climate. They have succeeded in very accurately modelling what has been happening through the period 1900-1997, even though when they started there were divergent results for some of this period. That is when they started the landbased and satellite readings were very different. They created the models, and these matched the land based readings closely, but no matter how hard anyone tried they could not be made to match the satellite readigs. The satellite analysis has since been shown to be wrong, vindicating the models.

    Warming since 1997 has been very much in line with what the models predicted, vindicating the models again.

    The models indicate that if we keep pumping CO2 into the atmosphere at current rates within about 25 years we will have a global disaster that will dwarf the second world war, and a few decades after that the survival of humanity starts to come into question.

    But its still not time to do anything. After all, of the time to predicted disaster available in 1997 we’ve only used a quarter testing the models. Maybe we should use half before we do anything, leaving us with only half the time to actually fix things.

    Fyodor, if you actually lived your life this way you would be dead long ago, having failed to get out of the way of a car because you couldn’t be sure it was actually there.

  67. August 19th, 2005 at 15:32 | #67

    Fyodor Says: August 19th, 2005 at 8:18 am

    Plagiarised Nabsy on shorter Strocchi: Fyodor is really pissing me off!

    I am not that angry at Fyodor. I take some time out to take Fyodor’s comments to pieces as a public service and private pleasure. I am sorry that he wastes other peoples time. I notice that Pr Q has given up on trying to argue with him, so someone has to do it.

    His intellectual tactics are borderline troll masquerading as conceited big mouth intellectual. His combination of arrogance and ignorance, an incoherent jargon with incendiary bluster, has a superficial plausiblity that just begs to be put down.

    It is a pity to see others mesmerized into watching a fool dig himself in deeper and alarming to see him entice them into the bog. Although he himself is apparently incorrigible, hanging him out to dry will encourage the others. Plus it is fun, since it is always enjoyable to highlight a big mouth putting his foot in it.

    Fyodor seems to have started this wild intellectual goose chase by confusing two aspects of mathematical modelling, roughly corresponding to the distinction between historical construction and theoretical application. :

    How do we know that the measurement data is a representative set of possible values?
    Does the model describe well the properties of the system between the measurement data (interpolation)?
    Does the model describe well events outside the measurement data (extrapolation)?

    A common approach is to split the measured data into two parts; training data and verification data. The training data is used to train the model, that is, to estimate the model parameters (see above). The verification data is used to evaluate model performance. Assuming that the training data and verification data are not the same, we can assume that if the model describes the verification data well, then the model describes the real system well.


    Using this terminology, the corrected satellite data can be read as independent (verification) data to the original (training) surface data. So the AGW model extrapolates well to fit disparate data series.

    Fyodor comes up with statements of the kind “That the models fit historical data is trivial and expectedâ€? which refers to interpolation – the efficiency of the model in respect to initial data. This neat dodge allows him to set aside the fact that the AGW model also extrapolates well to fit another data series (derived from a different point in space, rather than time), namely the satellite data.

    It is clear that Fyodor does not know what he is talking about. If commenters dont believe me then consider this sample of “directionless quibble”.

    Fyodor Says: August 19th, 2005 at 8:32 am

    it is not surprising that climate models developed to simulate climate change tend to match historical data, because their output is usually tested for a posteriori predictive power against historical trends.

    The risk in the model building and testing process is that the model builder works through so many iterations to “fit� the model to the historical data, that they lose the rigour of the science used in determining the key variables and the structure of the model, thereby producing a model that works really well at predicting the past, but may be lousy at predicting the future.

    I hope that clarified my position for you.


    Let me clarify this strange passage. Indeed “it is not surprising that climate models developed to simulate climate change tend to match historical data” since that is precisely the aim of fitting a curve. It would be back to the drawing board if they did not. Why is a statistician fitting a curve to data meant to be some extravagant intellectual vice? And what does “they lose the rigour of the science used in determining the key variables and the structure of the model” mean, I wonder?

    Fyodor Says: August 19th, 2005 at 8:11 am

    I agree with your concluding point, i.e. it looks like we have resolved the surface-satellite discrepancy.

    Fyodor has spent the better part of this thread arguing that the data discrepancies between satellite and surface reports is improperly resolved because the rotten modellers have only fitted (meaning retrodictively interpolated) the data to their models. Now he says that Global Warming (GW) models are ok since the data discrepancies have been properly resolved in favour of the GW model which is in accord (meaning predictively extrapolates) with data provisions and revisions! So all is forgiven to those “reckless” and “naive” modellers.

    This means that Fyodor implicitly concedes that models show that GW is occurring. I take it that he has back-flipped from his initial super-skepticism about modelling, in general, and the Anthropogenic GW model, in particular? One will wait in vain for a self-correction on this point.

    Instead of treating this discrepancy-resolution, as any fair and reasonable person would, as a predictive triumph for the AGW model he now withdraws to a falls back position – the AGW models fits key parts of space but not enough periods of time. It is, allegedly, too early to tell if the trend is cyclical or secular.

    Fyodor Says: August 19th, 2005 at 9:57 am

    If we take JQ’s “start� point of 1997, models have only been forecasting (as opposed to hindcasting) for around eight years. As I said previously, this is not a long time frame for testing the predictive validity of these models.

    Who died and made Fydor the Pope of indefinitely extending the duration of time series? A model that consistently predicts a year-on-year trend for more than a few years looks a pretty good bet to me. What are the odds that random noise or accidents will all tip the trend in the same direction?

    Fyodor insists that, deep down, he is really just a critical onlooker who cares only for the advancement of knowledge. Well they all say that. Will he set some benchmarks or litmus tests for the validation of his hyper-skeptical theory of Global Warming? How many years of increasing temperature, and how high will the temperature have to go, before he admits he is wrong? I would be inclined to say that Hell would Freeze over before we saw that happening, if it were not for the inapt natue of the metaphor.

    Fyodor also suggest that GM might not be anthropic in source, so maybe it is geologic, oceanic, cosmic, what ever, and it is only a coincidence that the temperature gets hotter now that 6 bill humans are all burning just about anything combustible. Or perhaps little devils are secretly cranking up everyones thermometer when scientists are not looking.

    By this time we are all so exhausted trying to follow the Byzantine path of Fyodor’s bizarre self-justification we might just be fooled into believing a little diabolical intervention.

  68. August 19th, 2005 at 16:09 | #68

    I’m sorry if Fyodor is confused by my explanation of how he was misleading but that’s often the way it is when someone is misleading i.e. showing how someone is misleading is often not a trivial process.

    Chris, I wasn’t confused by your explanation of how I was misleading, but the point of the paragraph. You start off by quoting my comment on the historical variation in temperature, then leap to a non-sequitur on satellite data, with no relevance to my quote. It’s not my fault you can’t structure a paragraph.

    Re: your second paragraph, it’s true I can’t be bothered to track down the actual data, but here is a sample of charts from several different reconstructions, several of which support my earlier assertion. As I said before, however, these are “reconstructions” of data sets, not accurate observations.

    Re: your third paragraph, I was under the impression that JQ determined the original issue of this thread. I’ll stand corrected if you can prove you’re the evil genius manipulating the good Prof.

    Re: your fourth paragraph, yes, I do have problem with bald statements like “the earth’s surface is the warmest it’s been in a thousand years”, because we simply don’t know. And, yes, you did say it. The quote from comment #31395 is:

    So the issue is now can we all agree that the earth is warming seriously, so much so that it’s the warmest in a thousand years, regardless of the cause?

    The reconstructions above suggest you’re right, but you didn’t qualify the statement with the caveats surrounding the integrity of the underlying reconstructed “data”. I apologise for being pedantic, but you’re the one fixated on the data.

  69. August 19th, 2005 at 16:36 | #69

    Stephen L,

    I’ll address your post in parts, if I may.

    Thousands of the world’s finest minds have spent decades trying to model the global climate. They have succeeded in very accurately modelling what has been happening through the period 1900-1997, even though when they started there were divergent results for some of this period.

    They haven’t actually modelled what happened from 1900 to 1997, as they only started modelling in the early 1990s. I hate to go over this again, but, given they already had the data from, say, 1900 to 1997, making the models fit the historical data was not a stretch. In fact, it’s expected. My point is that it’s much harder to create a model that can reliably predict future temperature and, as the models have only been around for, say, eight years, we don’t have much evidence to validate or invalidate them. A simple univariate trend model could have “forecast” the results we’ve seen, but that’s not evidence of predictive power. Correlation is not causation.

    That is when they started the landbased and satellite readings were very different. They created the models, and these matched the land based readings closely, but no matter how hard anyone tried they could not be made to match the satellite readigs. The satellite analysis has since been shown to be wrong, vindicating the models.

    IMO, that the surface and satellite observation differed was not a problem with the models per se, but with the hypothesis that global warming was actually taking place. I think this is a secondary issue to whether models are reliably predictive or not [the models simply reflect the data and structure that go into them: garbage in, gargage out], but JQ notes that several GW sceptics seized upon this as evidence of weakness in the models. I’m not particularly hung up on this issue, as I think JQ has shown that the discrepancy is fast being resolved in favour of the surface data, and that global warming is taking place.

    Warming since 1997 has been very much in line with what the models predicted, vindicating the models again.

    Eight years worth of model results for a complex and volatile system like the Earth’s weather is not conclusive about the models’ predictive power. As I state above, a simple trend model could have produced a similar result, but been totally worthless as a forecasting tool.

    The models indicate that if we keep pumping CO2 into the atmosphere at current rates within about 25 years we will have a global disaster that will dwarf the second world war, and a few decades after that the survival of humanity starts to come into question.

    The models may suggest that, but if the models are unreliable, so are their forecasts. Back to square one.

    But its still not time to do anything. After all, of the time to predicted disaster available in 1997 we’ve only used a quarter testing the models. Maybe we should use half before we do anything, leaving us with only half the time to actually fix things.

    Again, nobody has any accurate forecast of what will happen in the future, or when. This talk of deadlines is totally unscientific and redolent of hysteria rather than rational decision-making.

    Fyodor, if you actually lived your life this way you would be dead long ago, having failed to get out of the way of a car because you couldn’t be sure it was actually there.

    Very droll. Let me stretch the analogy further: I usually look in both directions, and listen, to make sure no car is coming before I cross the road. You’re suggesting we only need to look in one direction to make that decision.

  70. August 19th, 2005 at 16:46 | #70

    Shorter Strocchi: just to prove I’m not really, really angry at Fyodor, I’m going to have a stab at discussing the thread topic, and prove comprehensively that I am, in fact, a buffoon.

    Love those snappy one-liners, Auntie Jack. It’s good to see you’ve cut back on the aimless verbosity. However, please read my comments before responding – it’ll be less embarassing for you.

  71. August 19th, 2005 at 19:39 | #71

    Fyodor
    “1) Opinion is not science.” – Sorry in their scientific opinion which is based on their studies of the atmosphere – this OK?

    “2) Reread my previous comments about the limitations of scenario modelling.” The models give a range of scenerios and are reliable enough to assess the risk.

    “3) You’ve never seen me write that I might be wrong? I have, but for your benefit let me state it again, categorically: I might be wrong.”
    So now take the logical step and analyse the consequences of you being wrong. You being wrong means is that the global climate will change and people like you will have prevented action to reduce CO2. We will not be prepared and potentially billions of people could have their lives affected. Pretty bad consequences for being wrong!!!

    “We will only answer these questions when the effects are irreversible.
    Conjecture.”
    Not conjecture at all. The CO2 we are putting into the atmoshere will stay around for 50 to 100 years even if we ceased CO2 production now. So the buildup if it is left long enough will not be reversible at least in our lifetime.

    “Again, opinion is not knowledge. How can you be certain that you have enough information when you don’t know how the Earth’s weather works?”
    We have enough information to assess the risk.

    “ises? Absolutely. WTF does â€?…non-zero risk that the climate will change.â€? mean? History alone tells us that climate will change. That’s not in dispute.”

    History might tell us that the climate changes but not exactly when. History also tells us that sometimes it changes around the times when CO2 rises in the atmosphere. Without anthopogenic CO2 and human actions to reduce carbon sinks the climate might not be changing right now. You cannot say that there is a 100% chance that the climate will NOT change in the next 20 or 40 years due to AGW. While you cannot say this then there is a risk. This risk should be mitigated by action to reduce one of the main drivers of climate change – high levels of atmospheric CO2.

  72. Ros
    August 20th, 2005 at 00:30 | #72

    Despite the easy dismissal of the argument about the relationship between the sun and climate change it is very hard to feel comfortable with the declarations about the projections for the warming of the climate and who and what is responsible when the explanations are constantly changing. No doubt someone will explain with gusto why reports such as the following are irrelevant but it is difficult to believe the doomsayers when the only elements which seems to remain unchanged in the debate are political.

    “Typically, warming of the climate leads to increased melting rates of sea ice cover and increased precipitation rates. However, in the Southern Ocean, with increased precipitation rates and deeper snow, the additional load of snow becomes so heavy that it pushes the Antarctic sea ice below sea level. This results in even more and even thicker sea ice when the snow refreezes as more ice. Therefore, the paper indicates that some climate processes, like warmer air temperatures increasing the amount of sea ice, may go against what we would normally believe would occur.�
    http://www.universetoday.com/am/publish/sea_ice_may_increase_in_antarctic.html?1682005

    Scientists face difficult challenges in predicting and understanding how much our climate is changing. When it comes to gases that trap heat in our atmosphere, called greenhouse gases (GHGs), scientists typically look at how much of the gases exist in the atmosphere.

    However, Drew Shindell, a climatologist at NASA’s Goddard Institute for Space Studies, New York, NY, believes we need to look at the GHGs when they are emitted at Earth’s surface, instead of looking at the GHGs themselves after they have been mixed into the atmosphere. “The gas molecules undergo chemical changes and once they do, looking at them after they’ve mixed and changed in the atmosphere doesn’t give an accurate picture of their effect,” Shindell said. “For example, the amount of methane in the atmosphere is affected by pollutants that change methane’s chemistry, and it doesn’t reflect the effects of methane on other greenhouse gases,” said Shindell, “so it’s not directly related to emissions, which are what we set policies for…..
    After isolating each greenhouse gas and calculating the impact of each emission on our climate with a computer model, Shindell and his colleagues found some striking differences in how much these gases contribute overall to climate change……
    According to new calculations, the impacts of methane on climate warming may be double the standard amount attributed to the gas. The new interpretations reveal methane emissions may account for a third of the climate warming from well-mixed greenhouse gases between the 1750s and today. The IPCC report, which calculates methane’s affects once it exists in the atmosphere, states that methane increases in our atmosphere account for only about one sixth of the total effect of well-mixed greenhouse gases on warming

    http://www.physorg.com/news5258.html

    What makes it particularly suss for me is that projections are shouted as predictions and those predictions are confidently, though always with negative outcomes, extrapolated over decades.

  73. August 20th, 2005 at 12:52 | #73

    Ros – Reading the article that you posted it is very interesting that CH4 could be more of a forcing than we thought. This is both good and bad. Good because we can reduce CH4 reasonably easily and maybe keep some of our fossil fuels that we need so badly.

    Really really bad because of this: http://www.newscientist.com/article.ns?id=mg18725124.500

    “THE world’s largest frozen peat bog is melting. An area stretching for a million square kilometres across the permafrost of western Siberia is turning into a mass of shallow lakes as the ground melts, according to Russian researchers just back from the region.

    The sudden melting of a bog the size of France and Germany combined could unleash billions of tonnes of methane, a potent greenhouse gas, into the atmosphere.”

    So of this is true I guess we are pretty well screwed.

    This really goes to what Fyodor has been saying that we should not stop researching climate change. However it does not invalidate what I am saying that we have enough information now to assess that the risk of future climate change is sufficient to take action on reducing greenhouse gases.

  74. Mark Hadfield
    August 20th, 2005 at 14:31 | #74

    Fyodor

    One last try

    I hate to go over this again, but, given they already had the data from, say, 1900 to 1997, making the models fit the historical data was not a stretch. In fact, it’s expected.

    I hate to point out you haven’t gone over it yet, beyond making vague statements about “data fitting”. Please explain *how* you think the modellers made the models fit the historical (20th century trend) data. By fudging the forcing time series? By fiddling with a hidden knob in the back of the computer? Please tell.

  75. August 20th, 2005 at 15:35 | #75

    Mark Hadfield Says: August 20th, 2005 at 2:31 pm

    I hate to point out you haven’t gone over it yet, beyond making vague statements about “data fitting�. Please explain how you think the modellers made the models fit the historical (20th century trend) data. By fudging the forcing time series? By fiddling with a hidden knob in the back of the computer?

    Well said Mark.

    Fyodor assumes because some models have the GIGO form it follows that all models are suspect. That is, what Stove calls, the epistemology of the “silent scream”, where humanity is locked inside its intellectual structures, with no way of reliably transacting knowledge to or from the outside world. A recipe for “directionless quibble” from the one who knows best.

    He has failed to grasp the elementary distintion between empirical data fitting (interpolation) and theoretical data predicting (extrapolation). The AGW model is of course robust for historical data, and now tracks new data. In fact, the AGW model has now received independent corroboration from the satellite data, plus a steady time serial verification from the surface data.

    This would be enough to satisfy anyone but a paid hack of the coal industry or a malicious intellectual mischief maker. No prizes for guessing which category Fyodor fits into.

  76. Simon JM
    August 21st, 2005 at 11:17 | #76

    Ender throw in enormous peat bogs in Indonesia that could dry out and burn releasing huge amounts of CO2.

    I beginning to think we are actually going to have change on the extreme end of the scale. I heard somewhere that the IPPC actually have been being very conservative looking for a consensus and have been ignoring the evidence for a more extreme temperature change.

    Get ready folks its going to be a hell of a ride.

  77. Ian Gould
    August 21st, 2005 at 11:41 | #77

    >I’m beginning to think we are actually going to have change on the extreme end of the scale. I heard somewhere that the IPPC actually have been being very conservative looking for a consensus and have been ignoring the evidence for a more extreme temperature change.

    I forget the details but apparently the IPCC consensus forecasts are simply the arithmetic mean of the different models, when you start adjusting for the different confidence intervals and the differing quality of the models (based on back-casting capacity and the like), the likely warming figures shift up drastically.

    Of course, any such statistical manipulation is immediately suspect.

  78. Ian Gould
    August 21st, 2005 at 11:55 | #78

    Fyodor,

    On the one hand you have a computer model – input a affects output b according to a given mathematical formula and outputs c,d,e and e according to other formula; ditto for several thousand more inputs and outputs. Plug in numerical values for the inputs and you can run the model forward or back in time.

    On the other hand, you have empirical data for the actual past sdtate of the climate.

    Explain ot me, exactly, why you think its a trivial exercise to make the output of the first exercise match the empirical date, remembering that the model also has to demonstrate predictive value over the short term.

    I know a bit about computerised econometric modelling – mainly from the perspective of having been a government employee commissioning such studies and looking at the results – back casting is not the simple process you seem to think and demonstrating the capacity to back-cast is normally regarding as an important demonstration of the robustness of a model.

  79. Mark Hadfield
    August 22nd, 2005 at 06:50 | #79

    Ian:

    back casting is not the simple process you seem to think and demonstrating the capacity to back-cast is normally regarding as an important demonstration of the robustness of a model.

    That’s interesting: in the atmospheric science community it’s called “hindcasting”.

    And then we have “nowcasting”, which actually means short-term forecasting, based on simple extrapolations of the current state.

    But I digress…

  80. August 23rd, 2005 at 09:05 | #80

    test

  81. August 23rd, 2005 at 09:10 | #81

    I hate to point out you haven’t gone over it yet, beyond making vague statements about “data fitting�. Please explain how you think the modellers made the models fit the historical (20th century trend) data. By fudging the forcing time series? By fiddling with a hidden knob in the back of the computer? Please tell.

    Mark, “data fitting” has nothing to do with fudging data, or fiddling with knobs (except, perhaps, figuratively). Data fitting, as I stated here, is working and reworking, through many iterations, a model until its output, based on independent data input, matches the dependent variable being modelled. In the case of global warming, an example would be modelling global mean temperature as a function of many variables, such as solar radiation, volcanic activity oceanic feedback, cloud cover etc. Now, how is this model constructed? Do we set the parameters of the model based upon known scientific principles and relationships, or do we calibrate the model so that it matches the recent historical record? This may seem like a trivial difference, but it’s very important in retaining the scientific integrity of the model. My concern is that many models may be so manipulated to fit the data (i.e. so that they look accurate in hindcasting), rather than based upon sound knowledge of the underlying science (i.e. which would make them perform well in forecasting). As Ian Gould points out, the ability to “predict“ historical observations a posteriori is a good test of a model, but if such testing is used upfront to drive the model calibration, you risk losing the integrity of the model – all it becomes is a “fitâ€? to the past, not a useful model for predicting the future.

  82. August 23rd, 2005 at 09:24 | #82

    Well done, Jack: you’re learning. You may now address me as Dr. Pavlov.

    Your latest effort shows yet again, that your willingness to over-reach your limited intellect and understanding is unmatched. You’ve done nothing more than regurgitate what others have said, less elegantly. It is, however, a huge improvement in focus and brevity, and I suppose I should throw you a bone by correcting your mistakes.

    For your homework, please look up the meanings of “interpolation� and “extrapolation�. There’s no single “AGW model� and of course the models are historically robust – I said that point was trivial, and you’re simply repeating me. The recent work on satellite data doesn’t “corroborate� any models; it confirms the surface data.

    Full marks for “time serial verification�, however. That’s a really impressive Stroppylogism. Honestly, you’re downright embarrassing when you make this stuff up.

  83. August 23rd, 2005 at 09:37 | #83

    Explain ot me, exactly, why you think its a trivial exercise to make the output of the first exercise match the empirical date, remembering that the model also has to demonstrate predictive value over the short term.

    I know a bit about computerised econometric modelling – mainly from the perspective of having been a government employee commissioning such studies and looking at the results – back casting is not the simple process you seem to think and demonstrating the capacity to back-cast is normally regarding as an important demonstration of the robustness of a model.

    Ian,

    It is a relatively trivial exercise to make a mathematical model “fit” empirical data. It is done by selecting independent variables and coefficients for those variables that produce the best fit to the historical data. As you point out, this does not necessarily produce a reliably predictive model, and this is the point that I want to stress. Producing a model that can reliably predict future outcomes is much more difficult than producing a model that can “back-” or “hindcast”.

    I am also familiar with models of many kinds, and it’s not my intention to trivialise the work of the modellers. Rather, I want instead to emphasise how hard it is for them to produce really good models for such a complex system, and how sceptical we should be when using the output of models we know are likely to be flawed, given: a) the risks inherent to modelling; and b) our limited understanding of the forces affecting global temperature.

  84. August 23rd, 2005 at 10:31 | #84

    You may be interested in one technique they use in weather forecasting these days. They make a number of projections based on slight variations of the initial parameters. Typically they get groups of similar results, but not one single group, and maybe a few outliers. They then estimate the probable outcome based on the groups. This rests on having the computer power to do more than one projection before overtaken by events. Presumably something similar could be done with climate modelling; I don’t know if it has been done, though.

  85. Brian Bahnisch
    August 23rd, 2005 at 22:53 | #85

    PML presumably they do. I recall several years ago the National Climate Centre saying that 7 out of 12 models predicted an El Nino.

    But good forecasters also look out the window before issuing a forecast. There is a lot to observe at presesnt. Huge frozen peat bogs in Western Siberia melting, bits falling off Greenland and the Antarctic, loss of sea ice in the Arctic, northern Canada turning mushy, glaciers in rapid retreat just about everywhere, loss of snow on the Australian Alps consistently over 50 years, an increase of average temperatures in Australia of 1 degree, markedly drier autumns and winters, and finally, cricket matches being completed with not too much rain in England. I’m sure I’ve missed about 150 important signals manifestly clear to all who watch the weather.

    An old bloke with relatives in the Fassifern Valley (around Boonah, SW of Brissie) told me the other day that the farmers are confused and don’t know what to plant anymore when they do get rain.

    Not conclusive, mind you, but it’s getting to look awfully suspicious.

  86. Chris O’Neill
    August 27th, 2005 at 23:51 | #86

    Just because a decent climate model doesn’t come along until 1997 doesn’t mean we can’t go back to say 1975 and use only measurements that were made up to that time to test if the model gives accurate forecasts from that time onwards. Those forecasts from pre-1975 measurements can be tested against post-1975 measurements. Such tests would be part of the normal testing of the climate model.

    Fyodor doesn’t give the impression that he thinks anyone might have done such tests. I hope he doesn’t assert that noone has done such tests because that would be a pretty brave assertion to me.

    Saying that models have made forecasts from 1997 to now is thus missing the big picture. It may well be that the warming in 8 years is significantly less than any short term warming in the last 1000 years (although saying “many times” less is stretching it) but that’s missing the real point which is that warming in the last 30 years (about 0.6 degrees C) is more than any short term change in the last 1000 years, according to peer-reviewed estimates. Missing the real point is being misleading. I’d be very surprised if there was no model that confirmed this warming using measurements from before 1975.

    I may well be that JQ determined the original issue of the thread. Of course it may well be that the conclusions about the satellite data came into JQ’s head without him reading about it. Then again, maybe fyodor just has a problem with semantics.

    I asked fyodor if he wanted to just say we’re 99% certain the earth’s surface is the warmest in a thousand years but he ducked the question.

  87. Fyodor
    August 28th, 2005 at 09:06 | #87

    Fyodor doesn’t give the impression that he thinks anyone might have done such tests. I hope he doesn’t assert that noone has done such tests because that would be a pretty brave assertion to me.

    No, I don’t and yes, it would be.

    Re: the “big picture” in your third paragraph, the temperature data you’re talking about over the past 1,000 years is reconstructed. We simply don’t know – with accuracy – what the temperature record was like in the centuries before the 20th.

    Re: your last question, I apologise for not answering it – I wasn’t sure which of the four in that last paragraph wasn’t rhetorical. The answer is no, we’re not 99% certain. Determining such a level of statistical confidence for volatile data that is not observable is difficult, to say the least.

  88. Chris O’Neill
    August 29th, 2005 at 00:08 | #88

    Another part of the big picture is that the models can be tested for more than just 8 years of forecasting ability. Saying that testing for just 8 years of forecasts is an insufficient test is missing the point. The point is that the models forecasting abilities can be tested for forecast periods of 30 years or more. What forecast period is a sufficient test?

    Yes we don’t know what the temperature record was, long before the 20th Century, and this means that it was absolutely pointless trying to find out what temperatures probably were because they could have been absolutely anything. All the research on paleoclimate has been a complete waste of money. Seriously though any scientific research worth its salt makes probability range estimates of its results and indeed this has been done as shown in this Bureau of Meteorology jpeg. Such estimates can allow us to make a probability estimate of whether it is now the warmest in 1000 years. BTW I thought some of my earlier questions were reiterative and none were rhetorical.

  89. August 29th, 2005 at 08:09 | #89

    Chris,

    It’s not a true test if you already know what the results should be and can cheat by changing the model so that the output matches the “expected” result.

    I don’t really understand why you keep harping on about current temperatures being the hottest in the last 1,000 years. We know from palaeoclimatic research [See? It wasn't entirely pointless.] that temperature varies greatly over time, so if it is true what does it prove?

  90. August 29th, 2005 at 12:04 | #90

    Fyodor Says: August 23rd, 2005 at 9:24 am


    The recent work on satellite data doesn’t “corroborate� any models; it confirms the surface data.

    This passage is diagnostic of Fyodor’s methodological confusion and intellectual delusion. He is trapped, poor fool, inside the iron cage of his own solipsistic epistemology. Worse still, instead of trying to escape he has set about hardening the bars.

    I love the sneering “scare” quotation marks around the word “corroboration” – a perfect example of what Stove calls neutralizing success-words.

    One way to neutralize a success-word is to put it in quotation-marks. Such variations as these can achieve, partially or gradually, that separation of a success-word from its success-meaning, which quotation-marks sometimes achieve completely and abruptly.
    One such variation is what I call “suspending” success-grammar: putting a success-word in quotation-marks, not necessarily in order to neutralize it, but just with the intention, or at least the effect, of leaving the reader uncertain whether you have neutralized it or not. (This is the effect momentarily produced by signs advertising `fresh’ fish). It would be no use for such a philosopher, and everyone now knows it would be no use, to cry “stinking fish” about science. But it may well be some use for him to praise science as “`fresh fish’ “; especially if he does it often enough.
    The effect on the reader is characteristic. An episode in the history of science has been described to him, and it is described, as we see, entirely in words importing cognitive achievement. Yet by mere dint of quotation-marks, every single implication of cognitive achievement has at the same time been neutralized or suspended.

    And likewise for Fyodor to heap faint praise on “corroboration”. Thus the madness in Fyodor’s methodology encourages us to believe that empirical corroboration has not only not-occurred in this particular instance, it is perhaps a bad thing in general! Thus the enquiring mind, intoxicated with Fyodor’s epistemological poison, continues to scream in solipsistic silence.

    Fyodor does not appear to understand that independent data corroboration is what counts, in positivist methodology, as model confirmation. This is because positivists (the epistemology of most scientists) are not that fussy about the the explanatory elaboration of models – so long as their construction does not violate fundamental principles.

    They are “unscrupulous opportunists” (Einstein) who just want the black box (model) to crank out predictions (extrapolations) that track the data (dependent variable). In some cases, the more unrealistic and abstract the model the better, so long as the data is tracked accurately (Friedmans notorious F-twist).

    Fyodor believes that the surface data, which describes the behaviour of the dependent variable, is somehow contaminated by association with the, as yet not fully worked out, AGW model. The surface data is one measure of the (AGW-predicted) dependent variable which is global warming in general. Other measures could be ice cores, oceanic metrics etc.

    If the satellite data is in independent accord with the surface data then it does not matter how the AGW model is constructed – it is robust over time and accross space. The AGW is now geographicly, as well as historcally, robust. It has survived critical tests extrapolated accross a number of dimensions, not just interpolation along a single dimension.

    The satellite data is, in short, independent confirmation not an independent variable. It is not self-generated as an independent variable in the model, it is independently collected thats all.

    Fyodor, who suffers from a self-inflicted dose of the “silent screaming” epistemology that has spread like wildfire throughout the slums of academe over the past generation, simply cannot get it into his head that independent data is just that – independent not model-cooked. It is hard to believe that someone who purports to lecture experts in the field could dedicated so much brainpower to justify such a stupid pun.

    of course the models are historically robust

    It is important for commenters to note how much ground that Fyodor, the slippery customer, has conceded in this little aside. This is clear from the spate of “-casting” jargon that has just spread like a rash on this thread, all thanks to Fyodor’s intellectual mischief-making.

    He started off questioning the very idea of robust models for complex phenomenon (call this “non-casting”). Then he said that the models are only robust for the 1997+ time period of dedicated observations (“nowcasting”) because rotten modellers only interpolated pre-cooked data to fit their dodgy model. Now he says that, well of course, the models will fit data going back

  91. August 29th, 2005 at 12:08 | #91

    of course the models are historically robust

    It is important for commenters to note how much ground that Fyodor, the slippery customer, has conceded in this little aside. This is clear from the spate of “-casting” jargon that has just spread like a rash on this thread, all thanks to Fyodor’s intellectual mischief-making.

    He started off questioning the very idea of robust models for complex phenomenon (call this “non-casting”). Then he said that the models are only robust for the 1997+ time period of dedicated observations (“nowcasting”) because rotten modellers only interpolated pre-cooked data to fit their dodgy model. Now he says that, well of course, the models will fit data going back

  92. August 29th, 2005 at 12:19 | #92

    of course the models are historically robust

    It is important for commenters to note how much ground that Fyodor, the slippery customer, has conceded in this little aside. His retreat has been covered by an outbreak of �-casting� jargon that has spread like a rash accross this thread since he decided to make pronouncements on the subject.

    He started off questioning the very idea of robust models for complex phenomenon (call this “non-castingâ€?). Then he said that the models are only robust for the the 1997-plus time period of dedicated observations (“nowcastingâ€?) because rotten modellers only interpolated pre-cooked data to fit their dodgy model. Now he says that, well of course, the models will fit data going back before 1997 (“hindcasting”). It is only a matter of time before he concedes on “forecasting” (sorry, but Fyodor’s kind of intellectual baboonery encourages bad puns).

    Normally someone who backtracked this fast would be laughed out of court as an impostor. But give credit to Fyodor, the bluster that powers his unparalleled combination of arrogance and ignorance comes in handy in when covering hasty backtracks.

    It has been a relief for me that others have done most of the heavy lifting in disentangling fact, fantasy and fallacy from Fyodor’s plausible crankery. (Commenters have no idea how hard it is to provethat water typically runs down hill to a man who does not really believe in the concept of probable proof.)

    But I must also confess to feeling a certain shame in enjoying the spectacle of knowledgeable persons making mincemeat of Fyodor’s arguments, until nothing of his initial position is left but a tattered remnant. The scene exerts a certain gruesome fascination, like being a ghoulish on-looker at a car-wreck amongst. However, there is not much redeeming intellectual merit, so for shame we must avert our gaze.

  93. August 29th, 2005 at 12:30 | #93

    Shorter Stroppy: Fyodor is still pissing me off, AND he’s had the last word!

    What, no Dr. Pavlov? And after all I’ve done for you, you go and throw yourself off the wagon with a reversion to incoherent spray. You get a big Fyodor “F” for “Fail”, Auntie Jack.

    Also, please take care you don’t burn yourself on that Stove. The way you go on about him suggests the book pages might be stuck together.

  94. August 29th, 2005 at 15:49 | #94

    Fyodor Says: August 29th, 2005 at 12:30 pm

    he’s had the last word!

    No Fyodor, this-world reality has the last word. Fydodor has a big mouth which he is always sticking a foot in. But even Fydor’s yawning orifice cannot accomodate the whole world of facts.

    Question: What kind of fool thinks Australian political parties are not more cultural conservative now than a decade ago, that there was no significant Islamic sectarian aspects to East Timor civil strife, that Muslim jihadists did not show at least as much proactive aggression as Christian Crusaders during the Holy Wars and that Darwinism does not apply to humans at sub-special classifications?

    Answer: the Fyodor-ian kind of fool, thats who.

    This is the kind of foolish and mischief making attitude exhibited by the sort of person who denies the reality of anthropogenic global warming, and probably the civilising effect of gun control, simply for the self-indulgent pleasure of deological disputation or maybe because they are just plain dumb. And to give his insane, or insincere, epistemological ideas a bit of publicity.

    Oh how Fyodor would have loved the medieval period when his peculiar blend of ideological rigidity and specious hair splitting was accorded a much higher status than the kind of blogspatting that he adores indulging in these days.

    It is clear that Fyodor’s solipsistic mind is impervious to rational argument and incorrgible to empirical evidence. However, through the miracle of technological inventions and financial institutions, we have an alternative way of resolving the dispute that does not involve resorting to the cerebral domain of the mind. I am talking about a having a little wager, the sort of acquisitive activitiy that would appeal to the livid reptilian lobes of Fyodor’s mind, at least.

    Fyodor is, after all, a true believer in the perfectability of financial markets. So he would have to be impressed that his brother AGW skeptics are prepared to put their money where their mouths are, instead of their feet, like Fyodor.

    So, if he is prepared to stump up some cash, I am prepared to match him dollar for dollar on a bet that AGW is real and will continue to increase in magnitude. I think that the general conditions of the Mashnich/Bashkirtsev-Annan wager look fair enough to me. Pr Q to hold the bets and deciding fair value odds.

    The winnings, I suggest, should be directed to a reputable charity, as directed by the winner. The loser to eat crow in a media to be specified by Pr Q – perhaps this blog who knows?

    No bet that involves long term predictions of complex phenomenon is a sure thing. However, in any argument with Fyodor one is entitled to resort to a supplementary epistemological principle in order to deal with what we might call the “Fyodorising” problem (To Fyodorise : verb. To destroy facts in a ‘Fyodorian’ fashion, to ‘pillage’ the truth, poor or no fact checking, wild accusations, conspiracy theories etc.. – with apologies to Auberon Waugh).

    This Fyodorising thinker is a sort of reverse compass to the true position. I am pretty confident, given Fyodor’s previous abysmal track record on intellectual disputes, that the world will not be at great pains to seperate
    “Fyodor the foolish” from his money.

  95. August 29th, 2005 at 16:11 | #95

    Shorter Stroppy: No, I have the last word!

    Jackpot!

  96. August 29th, 2005 at 17:22 | #96

    So I take it that Fyodor is chickening out on my offer of a bet on the prospects of AGM? What a wimp! Although, given his form, its probably the smartest move Fyodor has made all day.

  97. August 29th, 2005 at 18:15 | #97

    Absolutely, Jack. I have no idea what the temperature’s going to be in 10 years. That’s the point of being a sceptic: I don’t believe.

    Why should I bet on it? I’ll leave that kind of activity to the credulous and financially incompetent. You, for example.

  98. August 29th, 2005 at 20:05 | #98

    Fyodor Says: August 29th, 2005 at 6:15 pm

    That’s the point of being a sceptic: I don’t believe.

    No. The point of a skeptic is to only believe something for which there is reasonably hard evidence. Not to be a “directionless quibbler” or someone engaged in promulgating a solipsistic epistemology.

    I’ll leave that kind of activity to the credulous and financially incompetent.

    Fyodor’s statement implies that the world’s long-term meterological modellers are mostly woolly minded suckers. Coming from a world-class scientst this would be considered a deplorable lapse in academic manners. Coming from a loud-mouthed lightweight like Fyodor it is just pathetic.

    As for financial savviness, I know at least one v-e-r-y scientificly minded multi-millionaire, with a great track record in the futures market, who wants a piece of that action, on the AGW side. And he sure aint Fyodor. So I guess that means Fyodor is all talk and no action, which we already knew anyway.

  99. August 29th, 2005 at 22:25 | #99

    I’m sorry, Jack. I didn’t mean to imply that the world’s long-term meterological modellers are mostly woolly minded suckers. I thought it was clear that you are the woolly-minded sucker. Hope that clears up any confusion.

    I’m very curious about your “friend”, however. Are you sure he’s not a teensy bit like your other imaginary friends?

  100. Andrew Reynolds
    August 30th, 2005 at 11:27 | #100

    Hmmm – the last 11 posts here were a (fairly boring) conversation between Stroppy and Fido. Get together over a beer and slog it out guys. I would pay to see that – although the hot air generated may noticably increase global warming (or is that AGW).

Comment pages
1 2 2572
Comments are closed.