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SkepticLance

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  1. Swansont. I don't think you looked at the graphs hard enough. The reference you posted for the USNA gave exactly the same graph as the one I posted, except that yours was in Fahrenheit, whereas mine was in Celsius. A difference that makes no difference. If you look again at the dark black line on the graph, representing the Canadian model that was adopted by USNA, you will see that it shows a temperature rise of 1.5C for the 20th Century. We know from history that the US warmed only 0.5C. Thus a 300% exaggeration. This makes the Canadian model prediction of 5.5C for the 21st Century look very suspect. Apply the 300% correction, and we are back to 1.8C. This is close to Hansen's prediction of 0.75C for 50 years. All this suggests to me that global warming models have been giving alarmist exaggerated predictions, which we should all take with a big pinch of salt. bascule. Posting the IPCC graph of estimated forcings again is not helping. Each of the values on the graph came from calculations and computer models. I think I have shown just how much we should trust computer models! When you can come up with real world measurements, please get back to us.
  2. The reason I posted that rather horrible reference, about the child dying, was not to say a vegan diet is beyond the pale. It was more a warning about extremism. Personally I believe that the vegan diet, though it can be healthy, is not as good as a diet which includes small amounts of animal protein. Although it is probably healthier than a diet with too much meat, and especially animal fat - a la McDonalds! As I understand it, the main problems that stem from vegan diets are lack of vitamin B12 and too little iron. The best source of dietary iron in assimilatable form is actually red meat. A lot of iron in vegetable foods is not readily assimilated by the human body. This is of special concern to women who are in their menstruating years, thus regularly losing iron. The consequence is that anemia is very common among vegan women. It is important for these women to either eat a little meat, or take iron pills. If you are too extreme in your views to do either, then it is vital to concentrate strongly on foods that have a bit extra iron. Among third world women, who are forced to eat a vegan diet through poverty, and especially those who subsist mainly on rice, the World Health Organisation estimates 100,000 die each year in childbirth due to their bodies being weakened by anemia.
  3. AzurePhoenix is travelling backwards through time, just like Merlin the Magician. Her ANCESTORS will live where? Personally I think the question of current human evolution is of academic interest only. Genetics as a practical technology is advancing so fast that we will soon be able to choose the genomes of our offspring. Future humans will be genetic 'supers'.
  4. If you are working out a lot, or engaged in any major athletic pursuit, the main extra thing you need is energy. ie carbohydrate. However, if you plan to be a strict vegan, be very careful. Vegan diets are potentially deficient in a number of things. Vitamin B12 has been mentioned, and is certainly one of the most likely causes of problems. Also the fact that we need 20 amino acids, and no one plant can supply all 20. A mixture of protein rich vegetable foods are needed. Also potentially deficient is iron, zinc and calcium. A lot of people think that animal protein is unhealthy. Not true. It is only excess that is unhealthy - just as anything in excess can be bad. The best way to ensure a completely balanced diet is variety. And that should, ideally, include a little animal protein. A bit of red or white meat, fish, or low fat dairy food can save an awful lot of problems balancing a vegan diet. To give you an idea of the hazards (they are worse for young people), take a look at the following reference, which shows a child that dies due to a vegan diet being too restricted. http://www.theage.com.au/articles/2002/06/13/1023864318459.html
  5. Homo sapiens has been in existence for something like 200,000 years, as a species. For most of that time, our ancestors were limited to bone, wood, and stone for technology. Only since the bronze age, and the iron age (3000 years) has technology been able to grow. It is reasonable to expect that, without copper, tin and iron, (copper and tin make bronze), that we would remain bone, stone and wood technologists for another 200,000 years.
  6. Swansont. You said you failed to get my evidence for the USNA graph. Here it is again. http://putfile.com/pic.php?pic=7/18500012879.jpg&s=f10 Sorry about the quality. I had to scan it from paper copy and upload to the putfile site. You will see that there are a series of models. The Canadian model, chosen for the USNA report, is the most exaggerated, and is shown by the dark black line. Why did they choose this particular model over all the others shown, which were less extreme? At the time, they reported to Vice President Al. Gore, who had set himself up Mr. Global Warming Messiah. It is normal human nature to do what you think your boss wants you to do. It would be very obvious that Al. Gore would prefer the most extreme model to support his extreme views. And so, his underlings would seek to supply him with the most extreme model. In this case, the fact that the Canadian model exaggerates 20th Century warming by 300% is the clearest possible indication that it is WRONG!
  7. bascule. The problem, as the 2003 convention pointed out, is that the global climate system is so complex that simple calculation does not cut it. We have an enormously compicated system of positive and negative feedbacks, with forcings of temperature up and down, and with numerous known and unknown parameters affecting results. You failed to answer my posting on the USNA models. The chosen model predicted 5.5C increase in temperature for the US during the 21st Century, while it missed predicting the known temperature rise of the 20th by 300%. Yet you expect us to TRUST these models????????
  8. bascule said : You're ignoring that the scientific concensus is coupled with empirical evidence of their position and a complete lack of scientific arguments for the opposing viewpoint. It's a triple threat. That is a remarkably cheeky statement to make considering I have asked you repeatedly for empirical evidence, and all you have been able to come up with is the result of calculations and computer models!
  9. Swansont said : According to the legend it's predicting temperatures for the US alone, which I would guess has to be a harder assessment to make, since it relies on more local factors. It's quite obvious that one area of the world can see different trends than the overall behavior at different times. Do you have a link that explains what the differences are between the models and their inputs? Whoops! You are right. I should have been more careful. My apologies. The graph does indeed refer to the United States. This does not, of course, change the point I am making. In fact, in a purely quantifiable basis, it strengthens the point. The Canadian model predicted 1.5C increase for the 20th Century, whereas the United States alone had an increase of 0.5C. The exaggeration was 300%, not the 250% I said. Just for comparison, the average temperature increase for the whole world was 0.6 to 0.7C. This means that, for the United States, the prediction of 5.5C increase must be reduced 3 fold, to 1.83C over the next 100 years. Again, I say, why the panic?
  10. Since bascule is so fond of computer models, let's take a look at one. Specifically, the Canadian model which was adopted as the centre-piece of the US National Assessment report in 2000. In the reference below, showing a range of model results, the Canadian one is the dark line. http://putfile.com/pic.php?pic=7/18500012879.jpg&s=f10 This model predicts a temperature rise of 5.5C for the 21st Century. However, it also predicts a temperature rise of 1.5C for the 20th Century; an exaggeration of 250%. If we apply a correction of 250% to its 21st Century prediction, to bring it into line with its amply demonstrated error factor, then the prediction for the 21st Century becomes 2.2C. This comes reasonably close to James Hansen's prediction of 0.15C per decade for the next few decades. Why would the US National Assessment choose a model that had already been proven wrong? Here's a clue. It reported to Vice President Al. Gore, who has just produced a movie!
  11. bascule, I am glad you agree that a computer model is a hypothesis which must be tested by empirical data. Something I have been trying to get across for ages. Has this been done? Not really. look at the latest IPCC predictions. The error factor is horrendous. The global climate is an immensely complex system, and we are a long way from being able to model it with reasonable accuracy.
  12. bascule. I do not outright dismiss models - just treat them with scepticism. Models that accord with reality, when the prediction is made before the event, deserve respect. So far, it hasn't happened. Temperature rise has not accorded with models. On average, models exaggerate temperature increases, sometimes by 300 %. I do not believe, however, models will ever be totally accurate, for the simple reason that some aspects of global warming are not predictable. Specifically I refer to such things as solar forcings. An international convention on global warming and computer models of the same in 2003 was disturbed by the revelation that cloud formation, details of cloud formation, and the consequence of cloud formation, could not be modelled. The global climate is enormously complex. Computer models still have a way to go before they can be accurate predictors of future climate. Just look at the error bars on current efforts!
  13. Dr. Dalek's views of computer models are very sound. Look at what the climate experts say. 1. Dr. Stephen Schneider, climatologist who is aligned to the catastrophist view. In his book "Laboratory Earth" he says : " ...computer climate models are over complex, and the results fragile." 2. Prof. Michaels, in "Meltdown". says : " climate models are simply strings of computer code that attempt to simulate the atmosphere. The key word is 'attempt'. If their output does not correspond to reality, they require modification. In the parlance of the scientific method, a climate model is a hypothesis in search of validation by observed data."
  14. Another reference for those who do not believe in solar forcings. http://pubs.giss.nasa.gov/docs/1998/1998_LeanRind.pdf Lean and Rind ascribe 30% of all warmings since 1970 to sunspot activity alone. This does not mean that greenhouse gases are 70%, since climate systems have many forcings.
  15. A piece of data for those who do not believe solar forcings can influence global climate. http://www.pnas.org/cgi/content/short/0603118103v1?rss=1 Glaciers in the Andes advance by amounts calculated to be caused by a 2 Degree Celsius drop in temperature, which coincides with a drop in solar forcing. All this during the Little Ice Age. If the effect of the sun's radiance was so potent then, why do people believe it cannot happen today? Bear in mind that sunspot activity, and therefore solar activity, increased throughout the warming period of the 1990's.
  16. Phanerozoic doG. Thank you for this data. Most interesting. Michaels points out the high Carbon dioxide in eras gone by, as well. Carbon dioxide in the Cretaceous once reached ten times the recent historical average. Temperatures reached a maximum of 10 Deg. Celsius more than the present. If you put that on a graph of carbon dioxide versus global temperature, compared to carbon dioxide versus temperature for the last couple of decades, you will see that the relationship cannot be linear. If carbon dioxide levels rise in a linear fashion versus time, temperature rise will fall off. bascule and Swansont. I might have guessed that you would distort the Hansen abstract. He says, clearly, that the most probable warming, according to his model is 0.15 Deg. Celsius per decade plus or minus 0.05 Deg. This equates to 0.75 in 50 years. You cannot cut it any other way. Of course, Hansen could be wrong. As could you, or I, or anyone. Which is what I have said all along.
  17. If anyone is interested; about the Hansen paper I cited earlier, showing that the likely warming over the next 50 years is likely to be in the vicinity of 0.75 Degrees Celsius ...You can get the abstract of this paper on http://www.pnas.org/cgi/content/abstract/98/26/14778
  18. bascule said : Now, can you please show me some scientific criticisms of the papers I've provided, or papers written by others which argue the other side? You are yet to produce one paper which corroborates the alternate hypothesis, namely that natural forcings dominate. I do not need to produce a paper because, as I have said repeatedly, I do not know, nor does anyone else know which forcing is dominant. If we do not know, we cannot produce 'proof'. bascule, my reasoning is based on a recognition of the doubts and uncertainties surrounding this issue. You think that is spurious. If so, can you explain to me why the IPCC cannot come up with a single computer model to give a single answer to virtually any question about global warming, and particularly why the IPCC reports predicted warming that might be 1.5 Deg. Celsius up to 6 Deg. Celsius over the next 100 years. How can they be that uncertain if the science is certain? The simple reality is that the IPCC is not sure of its details, and neither can you or I be.
  19. bascule said : Do you still believe that the assertion that anthropogenic forcings are primarily responsible for global warming is unscientific? bascule, it would make our discussion more meaningful if you would take the time to actually read what I have written. What I have said is that we do not know which is more dominant. A recognition of a lack of data to support a position is very scientific. Drawing definitive conclusions when the data is insufficient is very unscientific. I recognise that there is not sufficient data to say whether natural forcings or anthropogenic forcings are dominant. We know that there have been two major global warming periods in the last 100 years. Both gave a similar degree of warming. About 0.4 Deg. Celsius averaged over the whole world. 1. 1910 to 1940 2. 1976 to 1998 The first was not preceded by a large increase in greenhouse gases, but the second was. Both are associated with significant and substantial increases in solar activity as shown by readings of sunspots. The rational conclusion is that warming number 1 was caused by natural forcings and warming number 2 by both natural and anthropogenic. I regard this as a very rational position to take. Your adamant view that we know it all and it is all 'humans are guilty' is not a reasonable position in view of the facts.
  20. bascule. We would all take you a bit more seriously if you could cool the emotional outbursts. Good science is not emotional. On the business of computer models predicting Arctic warming would be greatest in winter, my most recent source is Prof. Michaels book. However, I also saw it a few years ago in an article by Dr. Stephen Schneider. Why are you unable to admit you made an error in claiming your data disproves my argument? No-one will hold it against you. I have even said that I do not believe that 'warmer in Arctic summer' data disproves your case. So here we have two studies that came up with different results. So what. It happens all the time in a whole range of sciences - all those sciences which are statistical rather than precise. And again, the main thing it points out is the confusion surrounding the whole field. To get away from a point that arouses such vitriol ... A few years ago, a group of economists (including four Nobel Laureates) met and calculated that $ 50 billion per year spent on Kyoto would return a social value of less than $ 1 for each dollar spent. They calculated that, if the money was spent instead on HIV/AIDS prevention, it would save 28 million lives and return $ 40 for each dollar spent. This information came from today's New Zealand Herald, which reprinted an item originally published in the Observer. Yes I know. You will tell me it is not a reliable source of data. Nevertheless, the point made above is valid.
  21. bascule. I looked at your data on winter temperatures in the Arctic with great interest. I accept that it shows a pattern opposite to the study Prof. Michaels quotes, and I accept that it is probably a valid set of results. What I suspect you don't know is that you just scored an 'own goal.' I have said, a number of times, that a computer model has to be treated like a scientific hypothesis. It must be tested empirically. This is done by using the model to make a testable prediction, and then testing it. One of thse testable predictions, from computer models based on the anthropogenic greenhouse gas hypothesis, is that warming in the Arctic will be primarily in winter. If we test this, and discover than the Arctic warms up more in summer, then we have falsified the basic hypothesis. Of course, this is a distorted view of one set of results. It is much more likely that your set of results, which appear to falsify the greenhouse gas hypothesis, is simply another of the many sets of doubts and uncertainties surrounding the whole subject. Swansont. You asked for the Hansen reference. Prof. Michaels gives in his index : Proceedings of the National Academy of Sciences, 2001.98, 4113-20.
  22. bascule said : Not according to the National Snow and Ice Data Center: bascule, there seems to be a misunderstanding here. You have shown average temperature increase in Northern latitudes. I said SUMMER temperatures. Winter temperatures increased 2 to 3 degrees, so the average was an increase. My point, though, is still valid. It does not matter if winter temperatures increase. So instead of minus 40, we get minus 37??? Is anyone concerned??? You seem to like James Hansen? Professor Michaels reports on his work too. Dr. Hansen looked at the horrible range of computer models and their widely differing results. He reasoned (sensibly, it seems to me) that the best models would be the ones that most closely modelled what has already happened. He chose the best model by this standard, and used it to predict the next 50 years. Temperature increase of 0.75 Deg. Celsius! Are you going to get all paranoid about 0.75 degrees over 50 years? If you do, I am sorry for you. I have to say, though, your repeated comparisons to creationists and their opposition to evolution is objectionable in the extreme. I find it most offensive and I ask you to stop. In biology, there are no authorities who support creationism. In Climatology, there are many who are sceptical of the extreme global warming views. There is an enormous world of difference.
  23. Another interesting datum, of relevence if you are a polar bear. Arctic warming is only winter. Summer temperatures have not increased in 100 years. Winter temperatures have increased about 2 to 3 Deg. Celsius on average. This has no significance in terms of polar bear habitat. In winter, it is way below zero, and that warming does not melt ice or snow. Arctic ice is thinning, but not due to warming. The thinning is from changes in wind patterns. At the same time, sea ice in Antarctica is actually increasing, at least as the long term trend. Total ice in Greenland is 'in balance' as the long term trend, though there are places where it gets thicker, and other places where it gets thinner. All the above from Prof. Michaels book.
  24. Swansont said : A predictive model uses a range of parameters because it's predicting future events, and some of the input data are uncertain. If you don't know (or can't know) a parameter exactly, you use best-estimate, best-case and worst-case values, and get a range of answers. e.g. we don't know how much CO2 will be introduced to the environment in the future, so you extrapolate and use a range of values, and you will necessarily get a range of answers. We don't know when there are going to be other events, like volcanic eruptions. To point to that as a weakness or flaw in the science either means you don't understand the purpose of modeling or are being intellectually dishonest Swansont. I have to assume I am simply not getting a message across. I am trying to get back to basics. I am not denigrating computer models, which can be useful scientific tools, not am I asking for conclusive proof. No such thing exists. I am just asking for the normal process of basic science. This is : Start with a hypothesis such as " Global warming is caused solely or at least predominantly by human release of greenhouse gases, and will lead the world into a catastrophic warming." Any scientific hypothesis must be able to generate testable predictions. If it does not, it is worthless. As witness superstring theory, which is (so far) no more than a useless mathematical exercise. Fortunately, the hypothesis above does permit testable predictions. I already gave one example in my previous post. The problem is that, when these predictions are put to the test, they give equivocal results. All I am asking from you is proper empirical evidence that is convincing enough to make the hypothesis probable. I have just begun to read an excellent book. Professor Patrick Michaels, Climate scientist at the University of Virginia is critically looking at the current global warming ideas in a book called "Meltdown." I think Dr. Cloud, bascule, and Swansont should get a copy and read it. Might cut a bit of their certainty down to size. Professor Michaels shows that global warming from 1750 to 1980 follows very closely the pattern of sunspots. He demonstrates from hard data that the global warming prior to 1980 has little if anything to do with greenhouse gases or human activity. He also believes that the warming from 1980 to 1998 is due to a blend of increased solar activity and human activity. (Sunspot activity reached a peak in the late 1990's). He quotes a report which studies the various IPCC scenarios, and shows that the most likely warming over the next 50 years will be no more than 0.75 Deg. Celsius - hardly catastrophic! Professor Michaels has worked with the IPCC and is painfully aware that most of the people there, including those who release reports to the media, are not scientists. The organisation has a majority of politicians and bureaucrats. It appears that some, if not most, of the IPCC reports are not endorsed by the majority of IPCC scientists. This has resulted in an exaggerated view of global warming being presented to the public. Let me finish by repeating, once more, my views of global warming, so that if you attack them, you are at least attacking the right target. 1. No-one yet knows the full picture. Doubt and uncertainty are rife. 2. The causes of global warming are more than one. 3. I accept that human activity is one factor, but I do not think it has been proved for a moment that it is the dominant one. 4. Catastrophist predictions are exaggerated and unlikely to happen.
  25. Dr. Cloud. I tried to download your recent report, without success. However, I suspect it is merely a variation on what bascule has tried to put up as evidence. ie. The results of assorted acts of logic, calculations, and models. These can be interpreted widely. Global climate models spew out all sorts of different predictions, depending on which assumptions are fed in at the front end. We are all familiar with these, predictions ranging from 2 Deg Celsius to about 12 degrees over the next 100 years. Let me throw you a bone. I demand proper, scientific empirical evidence. This type of evidence is based on the prediction principle. Dr. Carl Sagan said it best : "The core of science is prediction." This means that any scientific idea (hypothesis) has to be tested using predictive testing. You take the hypothesis and say, "If my hypothesis is correct, then I make the following novel prediction...." Then you run a test to see if the prediction comes true. The hypothesis we are dealing with is that global warming is caused by human activity, being an increase in greenhouse gases in the atmosphere. And I have accepted that most of the increase in greenhouse gases since 1910 is human caused. It is possible to make predictions. One such, half way successful, prediction is to say that, if greenhouse gases are increasing the insulating power of the lower atmosphere, we will see the greatest increase in temperature in areas that are very dry. Two such areas are high northern latitudes (Siberia, Canada, and Alaska), and the Sahara Desert. In fact this prediction has been demonstrated, mostly, to be true. The exception is the driest continent on Earth - Antarctica, most of which is actually cooling down. Conclusion; some of the global warming is actually caused by anthropogenic greenhouse gases. Is this the dominant cause? Debatable. The results are mixed. I hope, however, Dr. Cloud and Swansont (and bascule if you are still reading) that this will give you an idea of what is meant by empirical evidence.
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