SkepticLance
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Let me see if I can kick off this thread with a question, and see if we can get a good debate going without the emotion and hysteria. I am presenting a hypothesis. People designing global climate models on their supercomputers are not able to adequately simulate the process of cloud formation. This leads to serious problems, making long term predictions unreliable and inaccurate. In order to support this hypothesis, I am presenting the following reference, which discusses the efforts modellers are undertaking to try to overcome this problem. http://www.innovations-report.de/html/berichte/umwelt_naturschutz/bericht-37677.html Question : Does my reference support my hypothesis? Any other comments?
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Lockheed What counter-argument?
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iNow The issue we were discussing was clouds. How about talking about that if you have a point to make, and not just waffling.
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To Lockheed When you use words like pollute, you are committing an ad hominem attack. Stop it! For others who don't know what he is talking about, it would appear that he and iNow got upset because they did not like my sceptical approach to their predictions of future doom. There is no dispute about the basic principle of global warming, or its cause. However, when it was suggested that we would get a 3 Celsius warming in the near future, I suggested that was unlikely. Not impossible - just unlikely. We did not define 'near future', and I took it to mean just a few decades. I am not impressed by global climate models, which are still struggling with a number of unknowns. The one recently publicised is the difficulty of accounting for the effects of variable cloud formation. This suggests that the long term reliability and accuracy of these computer models is questionable. However, we do have one clear cut, reasonably long term trend. The past 30 years represent the first clear cut simple case where temperature rise is operating in response to just anthropogenic greenhouse gases, and there is little influence from other factors. Over this 30 year period, there is a steady warming of 0.15 to 0.2 Celsius per decade, and a total of 0.5 C warming for the whole 30 year period. The warming fluctuates up and down on an annual level, but over the whole 30 years can be approximated as a linear event. I am not suggesting that this means future warming must also be linear. However, unless some major change occurs ( such as major change in solar output), the deviations from the current trend should not be dramatic. If we assume that the warming stays close to the present trend, then warming by 2100 will be about 1.5 C. Of course, we cannot know exactly what the warming will be. By the year 2100, the world may have warmed by any amount from 0 Celsius to X Celsius. I have tried to point out the uncertainty of predictions, but get shouted down. Now, anyone else.
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To iNow Saying 'more handwaving' is just a way of avoiding a reply. You did this before. When I posted the rate of warming over the past 30 years, you asked for a reference. I posted references twice, which you must have found inconvenient, since they showed you were wrong. This time, I have told you that climate models are unable to account for cloud formation, and this is a problem with their reliability and accuracy. Again, you cannot rebut the statement. There is a damn good reason you cannot, because it is true. If I spent the time on google, I could find lots of references to this problem, which modellers are still working to correct. Why don't you just get honest and concede the point. Climate models are not able to account for cloud formation, and this is a serious weakness. The modellers themselves know it.
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To Lockheed and iNow These posts of yours are just hot air. How about addressing the issue. I have stated that the lack of ability by climate modellers to adequately model the effects of variable cloud formation is a significant detrement to the accuracy of predictions based on those models. I have also supplied evidence to back this statement. In response you call it hand waving. You gotta do better than that. iNow said earlier "Here is a link to the story from which you cherry-picked (I notice you left out the portion I bolded...hmmm):" Yes, I deliberately left out the statement that the inability to predict the effects of clouds could result in the coming situation being worse. The reason I left it out is because it is meaningless. It is a 'glass half full or glass half empty' situation. If you don't know what's going to happen, then you don't know whether what will happen is better or worse than your prediction. Not very helpful. The point of my argument is that climate models are unreliable. It is anyone's guess as to whether they are in error in a positive or negative way. And that is not the point I was making. My point is simply that they are not reliable or accurate.
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None of you has managed to refute the main point I made. That is ; climate modellers still are not able to accurately model the effects of cloud formation, and this leads to inaccuracies in models. Even Lockheeds posted reference actually says : "Predicting the net influences these feedback loops produce is possibly the greatest challenge facing modern climate scientists who are trying to determine our future climate." That is : feedbacks from cloud formation are NOT currently accounted for in climate models. Here is another reference. http://www.innovations-report.de/html/berichte/umwelt_naturschutz/bericht-37677.html I quote : "Of all the components of climate change, the aerosol indirect effect has the greatest potential cooling effect, yet quantitative estimates are highly uncertain," said Nenes, who holds dual appointments in the Georgia Tech School of Earth and Atmospheric Sciences and the School of Chemical and Biomolecular Engineering. "We need to get more rigorous and accurate representation of how particles modify cloud properties. Until the aerosol indirect effect is well understood, society is incapable of assessing its impact on future climate." "Current computer climate models can’t accurately predict cloud formation, which, in turn, hinders their ability to forecast climate change from human activities. "Because of their coarse resolution, computer models produce values on large spatial scales (hundreds of kilometers) and can only represent large cloud systems," Nenes said." The belief that GCM's can simulate climate change 100 years into the future with accuracy remains naive.
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It is almost ironic. People like iNow are ignoring what I am saying and accuse me of ignoring what they are saying. To iNow Re clouds. Clouds are ONE uncertainty in computer models. There are lots of unknowns. What I am saying is that this demonstrates that models are not completely reliable. Clouds are an unknown that has received some publicity. Other sources of uncertainty are still too poorly understood to even get much publicity. Such as biological effects on climate. And, no. I do not need to quantify the uncertainty. That is why it is called uncertainty. Because it can't be quantified. Once it is understood well enough to be quantified, it will no longer be an uncertainty. I gave a good reference to the fact that uncertainties over cloud formation generate uncertainties in computer models. iNow is repeating history. Because he does not like the fact that there is evidence against his assertions, he is just riding over it - essential ignoring the evidence. The whole point is that it is not possible to accurately predict the future. We can talk about probabilities. But that is all. Anyone who thinks that they can do more is engaged in intellectual auto-eroticism. iNow said ; "So, how is it, precisely, that you feel the climate models fail?" Do you remember the graphs bascule posted? I should have kept them to post again, but didn't. They showed a good correspondence within acceptable error levels with warming over the past 30 years. However, their simulation of the years before that were not good. In some places, they were way out. I would personally be very surprized if the last 30 years could not be reasonable well modelled, since the pattern was so straight forward. When things got complex, the models failed to simulate them with any accuracy at all. Lockheed is demanding evidence. I have given evidence of uncertainty in the impact of cloud formation. However, because it cannot be quantified, it cannot be 'proven'. On the other hand, if you have a reliable and accurate technique, it can be quantified, and therefore generate evidence. The onus is on you to produce that evidence. To Swansont Re Al. Gore Al Gore showed a temperature graph that was discontinuous. I accept that the rate of temperature rise may increase. It may also decrease, but an increase is possible. However, if it increases, it will do so in a gentle curve. Gore showed two straight lines and a sharp corner. I was pointing out that does not happen in nature. Al. Gore, like many other climate catastrophists, is basically dishonest, and misrepresents the science. You keep going back to claiming that I believe warming to be linear. What I have said is that it approximates linearity for the last 30 years, and it is improbable that a major change will happen in the near future. ie. based on trends, it will probably not vary much from the current pattern for a while. It may turn from an approximately linear pattern to a gentle curve, but dramatic changes are not so probable.
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To iNow The problem of cloud formation is not one that I have invented. It was a major topic of discussion in the international conference on climate modelling about 3 years ago, as reported in New Scientist. Australian printed edition. 24 July 2004 page 45. I quote : "While clouds have always been regarded as one of the biggest uncertainties in calculations of global warming, they are turning out to be more of a wild card than anyone imagined. The fear is that global warming will either reduce how cloudy the planet is, or significantly change the type of clouds in the sky, and their influence of the planet's radiation budget." Also " Clouds are clearly linked to water vapour. A lot of water vapour in the air eventually forms clouds. During their short lives clouds produce both positive and negative feedbacks." And so on. The tone of this article is negative and alarmist, which is normal for New Scientist. However, the admission is there, that clouds are a major unknown with unknown effects. Thus, the uncertainty in global climate models. As far as testing the accuracy of climate models - Bascule posted a bunch of graphs showing climate model back models for aspects of climate over the past 100 years. The models were very good at modelling the last 30 years, but got progressively worse beyond that. As I have said, the past 30 years were a very simplified case, and should be easy to model. A good model needs to do better than just that.
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iNow said : "Cloud formation is a local event, whereas climate is a long term average." Not true. Cloud formation MUST be influenced by the amount of water vapour in the air, and we know that warming increases water vapour. There is some satellite evidence that sunspots lead to more cloud formation. There is evidence from satellite studies that phytoplankton blooms over warm patches of ocean are associated with extra cloud cover. In other words, cloud cover and the type of cloud formation are variables that interact with surface temperature. How this feeds back into the whole system remains unclear. We know that low altitude cloud has a cooling effect, and there is some suggestion that high altitude cloud may be warming. None of these influences can currently be modelled by computers.
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From Swansont " But that also means you can't exclude a result, either." Correct. However, what we are talking about are probabilities only. I consider it improbable that long term trends that are very consistent will suddenly change. Unless, of course, a new factor enters the situation. For the past 30 years, we have had a steady increase in CO2 and a similarly steady increase in temperature. If this continues, then we can expect the temperature increase to remain steady. I saw the opposite in Al. Gore's atrocious movie. He showed the current warming as a straight line, and then added another straight line at a much steeper angle as the prediction. Al. baby; it don't work that way! Of course, a new factor could easily enter. It has happened before. It happened in 1910 when sunspot activity suddenly increased, and a 30 year cooling turned into a 30 year warming. It happened again in 1940 when sunspot activity suddenly fell and the world cooled by 0.2C. Something similar could easily happen again, but the outcome would be as likely a cooling as a warming. iNow said "You clearly were not, and I apologize for my error." And thank you for the apology. My respect for you just went up ten notches. "You seem incapable of amending your position when it's been proven false, and you instead keep repeating the same invalid claims as if they were never addressed." The problem, iNow, is that you never present evidence that I can find convincing. I am not interested in the results of calculations or computer models, as I have made clear in the past. These cannot be reliable when we are dealing with a system that contains so many unknowns. As I said before, climate modellers cannot even yet accurately model the effects of variable cloud formation. How can they quantify climatic effects when such basics are not yet understood?
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To iNow I do not believe I ever said that temperature measurements before 1970 were inaccurate or unreliable. Could you please point out where I said that? As far as I can see, the entirety of your last post was to refute things I never said .... To Swansont Also it appears you are misreading my earlier posts. I try to make it very clear that predictions are uncertain. I do not think I ever said that future warming would be linear. What I have tried to say is that a major change in the near future is unlikely. This follows simply from the fact that the last 30 years have been approximately linear, and since long term trends rarely change rapidly, a change to dramatic exponential growth in the next 30 years is unlikely. Sure, it could happen, but if warming becomes exponential, after 30 years of almost linear, it will probably do so gradually. You quoted my statement : "If you assume that the higher part of the warming range (ie. 0.2 C per decade) is correct, then it will take 150 years for a 3 Celsius increase in average temperature on Earth. " Did you fail to notice the first three words? I clearly noted the assumption that deduction was based on. You are fully entitled to dispute the assumption, and I will freely admit that assumption is uncertain. The warming range could indeed rise above the 0.2 C per decade. However, I would ask you not to ascribe to my statement a clear message that future warming must be linear. I did not say that, then, and I am not saying it now. It is all based on probability. I regard, in light of history, it unlikely that we will see a major increase in warming in the near future. You can disagree, and no doubt will. Mr. Skeptic said : "Why would you want to limit your data to that of the last 30 years to predict things more than 30 years in advance?" The short answer is that I don't. I have been at pains to tell everyone that I do not believe accurate predictions can be made at all. Why the past 30 years? Because that is the only period in which a clear cut warming in response to greenhouse gases can be seen. Before that, the situation was difficult. (iNow has an objection to me using the word 'murky', which is a shame, since I think it describes the situation well.) More than 30 years ago the impact of greenhouse gas increase was much less, because greenhouse gas increase was much less. In addition, the impact of other factors, such as sunspot activity, and possibly aerosol pollution, was much stronger. Thus, global average temperature went up and down in response to those influences, masking any effect CO2 might have had. In the last 30 years, sunspot activity, vulcanism, and possibly aerosol pollution have been more consistent, allowing the impact of greenhouse gases to become clear cut. iNow said "My sense is that limiting the data to the past 30 years is the only way that Lance can justify his conclusions regarding future trends." I hope you realise that this is getting real close to the ad hom you accuse me of. Watch out for the chance that you might be getting a wee bit hypocritical.
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To Mr Skeptic The team working on the idea of a space levator for NASA say they will be able to get it done by 2020. However, I am sceptical .... Your point about terrorist targets is a good one. I hope it will not stop the development, but I suspect the necessary security measures if you were going to be a passenger would be horrendous. You would need some way of keeping any aircraft well distant. Maybe you could hang anti-aircraft missiles off the elevator structure, and have them set up to automatically destroy any target within a set distance.
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I suspect that, to a minor degree, the fact that a pandemic has not begun, is partly due to the efforts of the medics who are fighting bird flu. We now have a lot of information on how disease spreads. By using this information, and fighting the spread of bird flu, a lot of cases and a lot of deaths have been avoided.
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To Mr Skeptic. Interesting point. Personally I am a bit of a romantic about that. I love the idea of a new wave of pioneers setting forth to conquer the galaxy. However, getting away from romanticism, and down to hard reality, it seems unlikely that will happen any time soon. When we think of the time gap between the last man on the moon, and the next moon landing ..... I think we will need a space elevator to permit any meaningful colonisation of other planets. And a second elevator down to the planet being colonised (Mars??). When do you think this might happen?
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Let me comment on linearity vs exponential growth. Swansont comments on the fact that CO2 growth has approximated an exponential growth curve. That is correct. However, it is a simplistic conclusion to say that this means future temperature growth must also be exponential. First : the response to CO2 growth as temperature rise is not one to one. It is a reverse exponent. If CO2 rises as an exponent, it may well (in theory)result in a linear temperature rise. Since I do not have a crystal ball, I am not prepared to say whether this will or will not happen. It all depends on how dramatic is the CO2 rise in future. Second : if we look at temperature rise over the past 30 years, which covers a time of exponential CO2 rise, the result approximates a linear rise in temperature. Not exact, since the data shows considerable variation year to year. However, if we draw a suitable straight line through the data points, it fits the graph (for 30 years only) just as well as a slight curve. For this reason, we cannot conclude exponential temperature rise over the past 30 years. If we cannot do that, then we are out of line concluding it for the next 30. The simple reality is that I cannot, and neither can anyone else, predict whether future temperature rise is linear or exponential or anything else. Current temperature rise approximates a linear rise of 0.15 to 0.2 C per decade. This, to me, makes it likely that dramatic temperature rises are not likely in the near future.
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I have a theory about the long term world population. It may be wrong, and someone may point out a flaw. It is based on the assumptions that the process below will not be interfered with by people tinkering with human genes, and that the female desire for children is at least partly genetic. In the short term (next 100 years) world population according to the United Nations will peak at about 9 billion, and then start to decline. The reduction in population will be slow - hundreds of years. I asked myself, in this world of declining population, who will be the mothers? It seems to me that simple evolution will kick in. Over time, a higher and higher proportion of the population will be descendents of women who want more than 2 children. If the desire to have children is at all genetic, then the desire will increase every generation, till eventually, most women will choose to have more than 2 children, and the population will start to rise again. If all this is true, then in the long term (maybe 1000 years plus) there will again be a population problem with too many people.
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To iNow Over the short term you are correct. Over the long term, a declining birth rate, if it goes below fertility of 2, always results in a declining population, except for the United States which has massive immigration.
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To iNow re the relationship. CO2 vs warming. From 1976 to the present, this is crystal clear. Before that it is theoretical and mathematical, for the simple reason that other factors are overwhelming the effect of the CO2. Since the other factors cannot truly be quantified, that makes the whole thing murky. A climate scientist may say that, between 1930 and 1940 for example, the CO2 increase creates a certain warming. However, the warming at that time was far greater than the CO2 calculation would predict. Why? Because of the effects of other factors, with in this case, sunspot activity, being paramount. Note that from about 1910 to about 1940, there was a massive increase in sunspot activity. Since the mechanism by which sunspot activity causes warming of the Earth is poorly, if at all, understood, it cannot be calculated. Thus, for that time, things are murky.
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For those concerned about population growth, I suggest you research the relevent United Nations web site. http://www.un.org/popin In brief, 50 years ago the average fertility (number of children per woman) in third world countries was 5.5. Today, it is 2.5 and falling. The world is NOT going to implode. The best estimate of the United Nations demographers is that it will grow to 9 billion within 50 years and then start to fall. In developed nations, the fertility rate is already below 2. Which means that the population, excluding immigration, is already falling.
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To iNow What I am responding to is the suggestion that there is something wrong with me restricting my affirmation of the current greenhouse gas/global warming relationship to the last 30 years. I do this simply because it is the only period where that relationship is clear cut. Some people do not seem to be able to understand that point and still claim CO2 is driving warming, even for periods where the world is cooling, for Finagles sake! You cannot get a clear cut relationship where other factors are so much more potent than CO2 that they drive the whole planet into a cooling period. Even for the time after 1930, the relationship is pretty damn murky. Only from about 1976 onwards does it become clear cut. And the other factors driving warming/cooling are NOT that well understood. As I have said before, sunspot activity is a potent influence on global temperature. Yet no-one actually knows for sure what the mechanism is. So how can we say we understand what is going on when one of the most potent drivers involves a mechanism that we do not understand?
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To iNow You may be reading into my statements more than I intended. CO2 has been increasing in the Earth's atmosphere since the beginning of the industrial revolution, and it will have a warming effect on the climate in response to the amount of that increase. However, up until about 1930, that increase was trivial. That is the reason that other factors have dominated global warming/cooling. For example : from 1870 to 1930, the increase was only about 10 ppm in total, or 1.7 ppm per decade. In the next 40 years, it ran at 7.5 ppm per decade. Then reached to over 10 ppm per decade. http://www.grida.no/climate/vital/07.htm (Please don't tell me that this reference is not good enough. This data is also accepted by climate scientists and I do not want to go through another trivial argument with you.) To imply that the minor CO2 increases until 1930 could had a significant effect on warming/cooling is not smart. I accept that any increase in CO2 will have a warming effect. However, the early increases were so tiny that they were totally overwhelmed in terms of effect by other factors.
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Dak said : "so yeah, it's not that i'm trying to 'daemonize' SL (or anyone else) for not having a 'politically corect oppinion' , it's just that i wish he'd stop cherry-picking and ignoring the obvious flaws in his arguments once they're pointed out." It amazes me that we still have so much fuss about so little. All this began when iNow, quite wrongly, queried the average warming figures for the past 30 years. I gave two perfectly good references which iNow chose to reject. No one else, except Pangloss, had the integrity to stand up and say : "Hey iNow, stop arguing. Those figures are right." I have not tried to argue that the data was linear, which is an accusation thrown at me rather often - I presume out of desperation, due to having no better argument. I merely said that, if we drew a straight line through the warming figures for the past 30 years, it would approximate a fit quite well. This is true, and does not consitute a claim that all is linear. On the other hand, to look at the very minor changes in warming rate over 30 years, and claim that is statistically meaningful evidence of exponential growth, is a load of crock. My comments about the psychology of group extremism are quite correct, and accurate in terms of what we know of human psychology. The principle applies to scientists as well as anyone else. This is a good reason why data is king. It is a good reason for being sceptical of interpretation. When a scientist like James Hansen comes up with an interpretation that is way out of line with the raw data (5 metre sea level rise in 100 years, versus 3 mm per year, which is what we know is actually happening), then we are right to be very sceptical of his interpretation. bombus said "I'd guess that over 50% of people are still skeptical about it because of idiots like Lomborg and Jeremy Clarkson" As I said numerous times. Don't criticise Lomborg till you read him. You just show your ignorance. Lomborg is not a global warming sceptic. He accepts its reality just as I do. He merely says that we would be better to put those billions of dollars of resources into more important humanitarian projects. You can dispute that idea if you like, but at least dispute with what Lomborg actually says - not just what your prejudice imagines he says.
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To Lockheed, who asked why I chose to limit the data set to the last 30 years. The last 30 years represent a simple case. We have steady CO2 increase and steady temperature increase with no other significant factors involved. If we look further back in time, the situation becomes more complex and the cause/effect relationships become more debatable. For example, the period 1941 to 1976 represents a period in which the net result is a 0.2 C cooling as global average. To talk about this period as global warming is literally incorrect, as it was, overall, a period of global cooling. Before that period, things are also much less clear cut than the last 30 years. 1880 to 1910 is another period of global cooling, while 1910 to 1940 saw a global average temperature increase of 0.4 C. Since the CO2 increase for the cooling 30 years is very similar to the CO2 increase for the warming 30 years, the cause and effect relationship is also unclear. What is obvious is that factors other than CO2 increase were having a very potent effect. Thus, I accept the recent warming as being the clear cut case, where anthropogenic greenhouse gases drive global warming. Before that, such claims become moot. Lockheed said "Well, you are going to have to show us the data for this claim then, because as we keep saying this assumes an exponential rise. " Can you specify? My claim or Hansen's? If you assume an exponential increase in sea level rise, then it is one hell of a kicker to meet Hansen's claim. Currently 3 mm per year. If that doubled, we would still see only 60 cm rise in 100 years. Hansen claimed 5 metres by the year 2100. This would be the exponential rise to beat them all.
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To Dak Get this clear. I have siad it about 1000 times before and I am getting sick of having to repeat it. I am NOT a global warming denier. I never deny good data. And the good data shows clearly that the world has been warming over the last 30 years at the rate of 0.15 to 0.2 C per decade, in spite of certain people trying to claim that is false. I also agree that the recent warming is due to human activity, and we need to do something about it. However, it is also clear to me that there is now a global warming industry that depends on extreme catastrophist predictions to obtain the backing they need. Even Dr. Stephen Schneider, one of the worst, was forced in a TV interview to admit he was in the habit of exaggerating the consequences of global warming. The psychology of that is very clear, as I detailed in my last post. Another example was a recent article in New Scientist by Dr. James Hansen, who predicted sea level rises of 5 metres before 2100. What an exaggeration! Sea level is currently rising at 3 mm per year on average. To increase to the point where his outrageous prediction came true would require an incredible change in ice melting rate. It would, in fact, require a very large part of the ice on the land mass of Greenland or Antarctica to melt. Since the interior parts of both are actually building up ice, albeit to a minor extent, this seems highly unlikely. It is nonsense like that which illustrates the principle of people getting together and reinforcing extreme views. My thanks to Pangloss. I know he does not agree with everything I say, but he is that kind of rare individual with the integrity to stand up for what he knows is right, even despite minor disagreements. I was quite disappointed to see that integrity lacking in others on this forum. When iNow was denying the rate of warming as I posted it, the silence from other people who knew damn well I was right, was very obvious. Good scientific integrity requires a person to stand up for the truth, even when they disagree with some of the positions of the person presenting that truth. Those who disagree with my position, if they have scientific integrity, should affirm the truth when I say it. Permitting a falsehood to stand shows a serious lack of integrity.