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The Reality of Climate Change?

  1. Jul 27, 2008 #1

    mysearch

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    While I have quickly looked at Monique's sticky thread on ‘Reviews on Global Warming’ I believe the scope of this thread is still relevant. If not, please delete, as I was only making a general inquiry.

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    It appears that the media, in general, is now committed to constantly reminding us that climate change is a disaster that is just around the corner. Likewise, films like the Al Gore film “An Inconvenient Truth” seem unequivocal about the facts supporting their claims about mankind impact on the planet. As such, it seems to be almost heresy to even question whether the ‘green’ position is factually supported by science. However, the other day I was posted a reference to an article, which appeared to cast doubted on the verity of the underlying data.

    http://www.kurzweilai.net/news/frame.html?main=/news/news_single.html?id=9087

    This article related to a report entitled “Climate Sensitivity Revisited” by Viscount Christopher Monckton. However, when I did a bit of research on the author I started to get some doubts about his scientific qualifications, so decided to see if I could find a better source of information. The following site seemed much better in scope:

    http://www.climatechangefacts.info/

    In addition, it author seems to be better qualified:

    http://www.climatechangefacts.info/AboutUs.html

    So my question simply relates to whether anybody in this forum has taken an impartial look at these issues and whether there is any validity in the suggestions that are apparently being raised about some of the issues associated with global warming.

    P.S. I am not an advocate of any position, simply interested in the real facts, so would appreciable any knowledgeable insights. Thanks
     
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  3. Jul 27, 2008 #2

    tmc

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    With Mann's hockeystick graph having been debunked (www.climateaudit.org) and temperatures having fallen continuously over the past ten years, as well as the IPCC review methods having come under heavy fire recently, more and more people are beginning to be skeptic about AGW. Not to mention Hansen's data being widely criticized, and his climate model now completely off the mark.
    There's also a long critique here: http://www.middlebury.net/op-ed/global-warming-01.html

    That's not to say the whole global warming thing is necessarily wrong, but it is definitely open to criticism.
     
  4. Jul 27, 2008 #3
    Steve McIntyre is not a scientist. I might as well ask the bank teller next door whether space-time has curvature. The "hockeystick" has not been debunked, only questioned. Hansen's work has been criticized, but not negatively by a majority of climate scientists.
     
  5. Jul 27, 2008 #4

    tmc

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    McIntyre may not be a scientist, but his work was still published in Geophys. Res. Lett... The work was definitely recognized as being correct.

    Hansen's work cannot be widely criticized, because very little of it actually goes to the public domain. Most of the raw data and analysis are never published anywhere, and his temperature records are increasingly different from other sources. Course, that may just be because his temperature record is the only correct one, but I find that hard to believe.
     
  6. Jul 28, 2008 #5

    vanesch

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    I think the honest answer is that the situation is not entirely clear yet. Come back in 40 or 50 years, and the issue will be settled. What I find sad in the mean time, is that the discussion has left the realm of science and has entered that of religion.
     
  7. Jul 28, 2008 #6

    mysearch

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    Many thanks for the responses, especially the ‘Middlebury’ reference in #2, which seems to tell a similar story to the ‘Climate Change Facts’ website referenced in #1. Having now read both, here are my initial (non-expert) thoughts for what they are worth:

    On the face of it, scientific analysis of the potential for CO2 to be the major contributory cause of global warming seems doubtful. Equally, given the % contribution of mankind’s CO2 emission to this factor, the case for Anthropogenic Global Warming appears weak, at least, in terms of CO2. In contrast, there appears to be sufficient well-founded science to, at least, suggest that there are other ‘natural’ causes of global warming, e.g. solar cycles etc. So, on the assumption that there are errors in Mann's hockey stick analysis, the long-terms variance in global temperature may not have been unduly influenced by mankind’s activity, even up to the present-day. Therefore, the knock-on effects of global warming, such as sea level rises, may be outside human control and any modelling of future sea level rises may be overstated, if inaccuracy exist in the underlying temperature assumptions.

    Now the inference may appear to be that I have concluded that we can simply write off global warming as a media-led conspiracy story that should be unmasked. However, I started to think whether this might be a mistake for a number of different reasons that has little to do with science. While possibly premature, on my part, I was wondering whether this whole issue had another dimension?

    Current estimates of oil, gas and coal are projected to last in the order of 50, 100, 150 years respectively. Without alternative energy sources, all modern societies will be in big trouble. Unfortunately, without some form of all encompassing incentive, i.e. financial, political and social, the research funding into new sustainable energy may not be adequate. Equally, the general public may not start migrating to these new alternatives, if they cost more and have other impacts on their lives. As a broad generalisation, people don’t like change, especially big expensive changes that impact their local environment, unless the alternatives appear far worst. So the thought that oil, gas and coal CO2 emission are the cause of global warming that will destroy the Earth for our children may be acting as a useful catalyst for action and triggering additional investment, and migration, to alternative energy sources, irrespective of whether it is based on sound science or not. As such, widely publicising a truthful answer to `The Reality of Climate Change` question posed by this thread may not be in the best interest of society, as a whole, if it triggers a return to complacency.

    By way of a footnote, it is accepted that there are dangers in ignorance of the underlying science, especially if it triggers development of inappropriate solutions, e.g. excessive bio-fuel planting leading to mono-agriculture dependency and higher food prices for 3rd world countries. Finally, apologises, if this commentary is inappropriate for this forum, but would be interested in any knowledgeable feedback, which totally contradicts these initial thoughts. Thanks.
     
  8. Jul 28, 2008 #7
    There are reasonably objective standards that apply in scientific work(s) of various kinds. A reasonable application of those leads to the conclusion that climate change is likely occuring and that man appears to have a contributory role in that. At a glance, we need only read position papers from APS, Sigma Xi, NAS, NOAA, NCEA, EPA, and (even) the CIA. Although there are dissenting voices within each of these communities, it seems unlikely that the majority in each instance is wrong.

    And, to compare McIntyre to Michael Mann (or especially Mann's late colleague, Walt Pilkey) is, IMHO, rather like calling A Brief History of Time a good textbook in theoretical physics.
     
  9. Jul 28, 2008 #8

    vanesch

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    One of these standards is prediction and falsification.

    That's of course such a minimalistic statement that it can hardly be wrong. I suppose that what one means by AGW is the projected *catastrophic* climate change by the end of the 21st century, mainly due to the emission of greenhouse gasses, and implicit in this is the urgent need to do something immediately and drastically about it.
    I think it is *that* prediction which is not yet firmly established, although plausible, because that prediction is the result of model predictions which are each based upon doubtful hypotheses, the main of which being the supposed feedback mechanism which turns a half-degree equilibrium heating into a 6 degree heating.
    The half-degree heating comes from the simple radiation transport balance, and one needs a serious positive feedback (albedo, but mainly cloud formation, water in the atmosphere, ocean currents, ...) by processes who are not yet understood.
    The reason why I can make that statement is that the very models that predict these 6 degree heatings had already predicted stronger heatings for the last decade than has been observed (that's an understatement). So those models are hereby falsified. Of course, after the fact, they are corrected to fit the data again ("multi-decadal oscillation" ?).

    http://en.wikipedia.org/wiki/Atlantic_Multidecadal_Oscillation

    http://www.aoml.noaa.gov/phod/amo_faq.php

    http://www.realclimate.org/index.php?p=38

    And here:
    http://news.bbc.co.uk/2/hi/science/nature/7376301.stm

    Translated: the IPCC predictions (rising temps) are not observed in the short term. The didn't include it. Nevertheless, it was "obvious" (after the fact):

    Of course, nobody from the IPCC made public statements that the rapid temperature increases observed in the 90ies might NOT be exclusively due to AGW. They were of course not used to show a falsely alarming picture (or did they ?). But now that the trend doesn't continue, it is of course due to a new and unexpected but not surprising (huh?) oscillation known since the beginning of the 20th century (huh?).

    In short, one shouldn't pretend to know what one doesn't know yet for sure. That doesn't mean of course that there is no AGW, and that doesn't mean that AGW might not be catastrophic, but as of now, this has not yet been scientifically demonstrated beyond doubt - at all. Nor has the opposite, btw.
     
  10. Jul 28, 2008 #9

    tmc

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    Oh absolutely. But that doesn't make the hockeystick correct. I think Mann just made a monumental blunder which was caught by an outsider. It also doesn't make Mann's other dozens of papers less valid.
     
  11. Jul 28, 2008 #10
    You are quite correct in both assertions. We are early in the development of a theory and need to be able to make predictions to see if they can then be falsified. That will most likely be a back-and-forth process, where one theory is trotted out, tested, modified or discarded, a competing theory put forward, and so on. Did you by chance read the commentary on Nader Haghighipour's article in the latest edition of American Scientist, describing how the idea of planets orbiting binary stars was put forth, retracted, then reconsidered?

    The problem is that the general public, who by the political process must approve of any actions, generally doesn't understand or even like science. So, when this testability process is carried out, misunderstanding often arise as to whether "scientists know what they're talking about". Critics like Monckton and McIntyre often use this to their advantage by pointing out details that are wrong. Thus, if Hansen's temperatures are incorrect by 18%, climate change must be wrong, rather than saying that the model needs refined. We have seen this process used in the debates over relativity, smoking, evolution, stem cell research, energy, and now climate change.

    So, I framed my questions as simply as I could. If there is climate change, and if man contributes, then there is legitimate cause to ask the questions "How much?" and "Can it be ameliorated?".
     
  12. Jul 28, 2008 #11

    vanesch

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    But then summary reports like the IPCC do the opposite, and claim that the truth is established (not the more detailed reports, BTW, it is interesting to observe the difference in tone between the "physical basis" report, and the summary report for decision makers).

    But I will tell you why the attitude of the AGW/IPCC crowd makes me nervous, and makes me think of a group-think attitude (or a pseudo-religious attitude with a battle between "believers" and "non-believers"). The main error they make IMO, on purpose, is to assign wrong Bayesian probabilities to their conclusions. In other words, to display certainty where uncertainty remains. Again, I'm not saying that what they claim will turn out to be wrong, and that there is definitely no AGW. But I claim that they cannot predict with certainty a catastrophic AGW. Now, one can be of the opinion that displaying a bit more certainty than one actually has doesn't hurt anyone, as this will in the case one is right, favor more action than if one displayed accurate statements of uncertainty. And in the case one is wrong, well, limiting the CO2 emissions somewhat won't hurt, right ?

    But that is wrong. First of all, it is dishonest and bad science. But it is also wrong for another reason. Decision making is based upon comparing risks and benefits, including the uncertainties. If one tells you that with 20% probability, there will be a disaster that will cause one 100 million lives to be lost, but that in order to avoid this, one needs to take an action that will kill 30 million people with certainty, then the best thing to do is not to take that action. Indeed the expectation of victims is 20 million in the first case, and 30 million in the second. Of course, if the probability rises from 20% to 50%, then action is now more beneficial.

    So the amount of uncertainty is an important part in the decision making process, and cheating on that can lead to wrong decisions. Imagine that the probability for 10 degrees warming is really 1%, but one displays this to be 90%. In the latter case, a 10 degree heating is so dramatic that one needs to take drastic action. Even if half of the world population will die of that drastic action, it is still the right decision. However, that is a totally misguided course of action in the 1% case!

    I think that in 3 or 4 decades from now, one will have a much clearer picture on the AGW issue.
     
  13. Jul 28, 2008 #12
    I see your point. However, that in no way disproves the work of either Mann or Hansen. The issues still remain: Is there scientific evidence of climate change? Is man contributing?
     
  14. Jul 28, 2008 #13

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    Your question isn't as clear as you make it out to be.

    Is there scientific evidence of climate change? Well, how do you define climate change? Obviously, yes, there is evidence that temperatures, on average around the globe, are higher today than they were, say, forty years ago. This alone, IMO, doesn't constitute climate change. Real climate change should also include the ideas that temperatures will keep rising in the near future, and will eventually rise up to a point higher than what could be argued as normal. In other words, I see climate change as being temperatures rising to a point quite a bit higher than the MWP in the northern hemisphere, and to at least plateau there for some time, or keep increasing. Recent temperature records, however, show that the temperature may already have stopped rising, though it is still much too early to tell for sure. In any case, I would argue that there is no clear evidence that climate change as I have defined it is happening. Temperatures have risen a bit, they may rise a bit more in the near future, but I disagree that there is clear evidence that such temperature increases are unprecedented, dangerous, or that the temperature will keep on rising.

    Is man contributing? Again, the issue is in the details. Technically, yes, man is spewing lots of CO2 in the atmosphere, this CO2 will create some sort of increase in temperature, so yes, man is contributing. How much is man contributing should be the question. We can pretty accurately estimate how much CO2 we've sent to the atmosphere, so the question then becomes whether we can accurately model changes in temperature due to changes in CO2. The answer is a clear no, or at least not yet, as every model has failed miserably at predicting recent temperatures. But the models are now being updated with the new data, and these new models may fare better. We'll have to see. In any case, I would argue that we currently do not know how much climate change can be attributed to man.

    Ultimately, I think a number of scientists have jumped the gun, and called the issue settled far earlier than they should have. They're not necessarily wrong, but I think they're getting ahead of themselves. If they turn out to be wrong, it will take a very, very long time for scientists to gain the trust of the people again. And if in 30 years, we actually do start to cause global warming through some cool new technologies I'm sure we'll invent, everyone will just go, "yeah, but remember that time when they were wrong before?". Kinda like how now, lots of anti-AGW people use the argument of the global cooling debacle of a few decades back, the magnitude of which was nowhere near what this one could become (in part because most scientists at the time disagreed with the global cooling hypothesis; it was mostly a media scare).



    Mann's work isn't necessarily wrong, but the hockey stick graph is. He's done a lot of other stuff and I doubt he'd still be getting published so much if all of his work was wrong. The problem isn't so much that he made a mistake somewhere, but rather that the hockey stick graph had been the centerpiece of the popular presentation of global warming. The point isn't to discredit Mann himself or any of his other research, but rather that the hockey stick graph is the most prominent figure of the IPCC reports.

    Similarly, Hansen's models were wrong. He predicted temperatures for the past decade which were completely off the mark with what we've seen. Thankfully, science tends to work in the long run. He's continuously modifying and tuning his models according to new data, and I'm sure his newer models are much better than those he used to make those predictions. And in a few years, we'll see how these new models fare up against the new data. The reason he's often talked about, however, is that he first created a model showing gigantic temperature increases, then used these then-unproven, and now disproved models(he was off by an order of magnitude...), to go public and talk to the media every day, saying things like oil CEOs should go to jail and the likes. No matter how you look at this, it isn't science.
     
    Last edited: Jul 28, 2008
  15. Jul 29, 2008 #14
    Referees don't reject papers for religious/political reasons.
     
  16. Jul 29, 2008 #15
    Whether there is something wrong with the "hockeystick" is as relevant as whether the arguments by Copernicus that the Earth revolves around the Sun were 100% rigorous.
     
  17. Jul 29, 2008 #16

    tmc

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    The hockeystick graph implied that the temperatures achieved over the past century were completely out of the ordinary and potentially dangerous. By reintroducing the MWP into it, you instead get the feeling that temperatures are simply coming back up to levels which have previously been attained without major loss of life (and, debatably, actually better living conditions) after a small ice age.
     
  18. Jul 29, 2008 #17

    vanesch

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    Most scientific papers don't make the strong claims the IPCC summary reports make.
     
  19. Jul 29, 2008 #18

    Evo

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    They apparently do for personal/political reasons, read the IPCC report 1 that they hid from the public.
     
    Last edited: Jul 29, 2008
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