SkepticLance

I have read articles on this. The biggest problem is energy loss. Pumping water uphill loses 20 to 30% of the energy, and other factors increase this to an overall loss of approximately 50%. When you generate power, and lose half of it trying to store that power, it is not generally very economical. It can be done for special purposes, or when energy availability is substantial. But for most places, it makes little sense to waste so much power. A better approach, which does not waste power, is simply to use a wide range of energy generation options, to cover all needs. As previously mentioned, hydro-electricity without pumping uphill allows for short term increase in generation when needed. Nuclear runs 24/365. Wind power gives good generation when the wind is right, and solar when the sun is bright, but they need to be backed up by generation methods that do not suffer the inherent variability of wind and solar.

To Glider I guess my phrase 'non emotional thinking' was a bit ambiguous. And I agree that it is almost impossible to achieve in its entirety. How about a duty to make an honest attempt to think and express ideas in a rational manner, and consciously try to avoid emotional logic in such? Interesting idea about arousal in disaster thinking. I have tended to assume it was a kind of Messiah complex. That is : "I predict a disaster, but don't worry. I am here and all you need to do is follow my lead and all will be well." This makes disaster prediction another attempt to gain status. Do you think there may be any merit in this idea?

Since there seems to be some people on this thread with good knowledge of psychology, can I ask a couple of questions? 1. Is there not a duty for those of us who espouse science to set a good example of rational, and non emotional thinking? 2. I notice that there seems to be a lot of people who revel in disaster predictions. They make predictions and seem to enjoy the thought that these disasters will happen. Could someone comment on the psychology involved?

To Mr Skeptic Good point. I guess today's reality is mainly lack of precision. There have been times in the past when they have also been inaccurate, in that (eg Antarctica) they modelled warming when the reality was cooling. At this point, I cannot be sure enough of either to trust in the predictions (whether conditional or not) of global climate models.

I really do not care whether you believe that climate models are inaccurate because of poor computer resolution as iNow said, or because of unknown factors as I have been saying. The point is that climate models are not accurate. If you agree with that point, I am happy. I am off to Australia tomorrow for a week, so won't be able to continue your debate for that period. Cheers.

Just finished reading an interesting article in New Scientist : 30 August 2008 page 34. The theme is the way people let their emotions dictate their conclusions, even when rational thinking would dictate something quite different. The first bit of this article is found on : http://www.newscientist.com/channel/being-human/mg19926711.500-how-to-keep-your-head-in-scary-situations.html I expect the full text will become available in due course, after readers of the paper versions have moved on. An example of what they are talking about is the travel decisions of people after 9/11. In the 12 months following, many Americans chose to drive rather than fly, leading to an increase in deaths by road accidents of 1600. Yet terrorism of the 9/11 type has killed fewer Americans than lightning strikes. It appears that bad decisions are more likely if the subject is one involved in strong emotion. Words like 'terrorism', 'cancer', and similar can influence the decision making process leading to very poor thinking. What of thinking here on the science forum? I am certain some of the messages placed are more influenced by emotion than good rational logic. I would like to quote from the New Scientist article, the words of Dr. Dan Kahan, researcher at Yale Law School. "If as a citizen you would like to form well considered views on a culturally divisive risk issue - for example, global warming, or gun control - find a knowledgeable person who shares your general cultural outlook, but who disagrees with you. You are likely to give this person's arguments a sympathetic hearing, which will help offset the natural disposition we all have to dismiss as unreliable and biased the views of persons whose basic outlooks are different to our own." Sadly, I have seen little of this good advise being followed. Disagreement seems to arouse more emotion than ever.

I used the example earlier of a new oceanic current making models inaccurate. It appears that oceanic currents are quite a problem. Recently it has become clear that giant ocean circular movements called gyres have a very strong impact on climate. http://www.sciencedaily.com/releases/2008/09/080909094745.htm These have not been well enough understood to be part of climate models up to the present.

I propose a new law making it illegal for lawyers to enter politics. Only people with science degrees are to be permitted. After all, the present Chinese government is loaded with science graduates, and they have the fastest growing economy on Earth. Oh damn! Just remembered. There are so many lawyers in government we could never pass such a law.

Actually, CaptainPainic, we still need quite a lot of technological development to switch to carbon friendly life styles. These are being developed, but the change over will take a few decades. For example : we now have hybrid cars. The first plug-in hybrids will be on the market soon, permitting a car to be run as a pure battery operated vehicle for the normal short trips most of us use cars for. After that comes long range electric cars, and beyond that still comes rapid recharge (10 minutes), long range electric cars. In the mean time, that will not work for trucks and buses for long journeys, and we need to develop fuels for them, such as biofuels and synthetic fuels. That development is also under way. Abundant and non carbon dioxide generating electricity will be required. This need will be met by a range of methods, including new generation nuclear, hot rock geothermal, wind, tide, ocean waves, solar etc. Again, a few decades will be required to develop and build these generating plants. Deforestation needs to be stopped, and a regimen in place to plant two trees for every one that is felled. You may be surprised to know that this is also under way, and the western world is already doing it. New farming methods need to be instituted, and will be. The research into these new agricultural methods is already being done. The thing is : we know what needs to be done, and it is being done. It will not happen overnight, and there is no point rushing into precipitous and stupid measures. The felling of tropical rainforest throughout Indonesia to plant palm oil for biodiesel to supply the EEC is an idiocy we need not repeat.

iNow You are nit picking. A conditional prediction is still a prediction. A model may say, if condition A is met, then result B will occur. That is still a prediction. If there was no prediction, then the model would be useless. Just as a hypothesis that does not permit predictions for testing is also useless. That is the basic reason why super-string theory has got nowhere.

To CaptainPanic I agree with you that sending CO2 into space is not a smart move. There are much better ways of dealing with it right here on Earth. However, we should not suggest it cannot be done. A space elevator has to go about 78,000 kms into space anyway to be able to work. The energy to lift things up the elevator, whether by carriage or by pumping, can be done using nuclear power - hence no CO2 emission. If the CO2 was released into space beyond the 35,000 km mark, and especially if released way out at 78,000 km, the centrifugal effect will flick it out into space, and it will never fall back.

To Edtharan I have never said that models are not useful. I have said that they do not permit accurate predictions, which is a different thing. The reason is mainly due to the fact that there are still a whole lot of unknown factors not accounted for in models. An example I gave some time ago was the prediction of ice melt at the Arctic. The models predicted an amount that was 100% out (the actual melt was double what the model suggested), and the reason was that a warm oceanic current was carrying heat north. This current was slow and was not detected until recently. That is : an unknown factor was present that caused the model to be wrong. I regard models at this point in time as research tools. They help to increase our knowledge by permitting a kind of predictive test. As in : "My model as it currently exists predicts that in ten years something will happen." We wait ten years and see if the model is right. If not, we can modify the model. Eventually, the models will become much more reliable.

There are an awful lot of materials in food of 'natural' origin which are not restricted, for the simple reason that you cannot stop them occurring. For example : we have all been taught to cut out any green in potatoes. That is because the green area (chlorophyll) also contains a natural insecticide - an alkaloid toxin - that can make people sick and even kill them. There was a case in the 1970's when a new strain of potatoes was bred, and a researcher cooked some of them for his meal, and died. That particular strain happened to have excess amounts of this poison. Anyway, here is another food myth. That legally permitted sprays cause food to become harmful. In fact, the opposite is frequently true. If an insecticide spray is used according to directions, the final residual amount of insecticide in food will be one part per million by weight or less. This amount for modern sprays is quite harmless. The insecticide, though, can prevent insects transferring plant diseases that can harm humans. In maize, for example, there is a fungal disease spread by insects caused by the Fusarium fungus, which causes a build up of a fungal toxin, fumonisin. This can lead to a human fetus developing abnormally with neural tube defects. One such is anencephaly - being born with no forebrain. And the incidence of this is much higher among people of Mexican descent who traditionally grow their own, unsprayed maize.

Mechanical deboning of meat is done simply because it is cheaper than manual. The bone flour is ground off because the mechanical device is powerful - lots of horse power. The best high calcium meat is mince (hamburger) since the bone flour is mixed in with the meat.

I like it! Ethanol from corn was never going to be more than a drop in the ocean, and acts to boost food prices in a hungry world. Whole plant digestion using these new bugs seems a lot more practical. We can digest the corn plant - all except the food grain - and make far more fuel.

I am surprised no one has gone for immortality, which is a common theme in Scifi. For example ; you could go for ascendency, as the ancients achieved in Stargate. Mind you, wherever I went, ascendency or anywhere else, I would want to take Seven of Nine from Star Trek Voyager, as my sidekick.

My argument is that our artificial coverings have changed our natural covering. That is : once humans learned to make warm clothing, the need for a thick hair covering disappeared, and having a thinner covering which could be enhanced at need was a real advantage, permitting better cooling in hot conditions, and better parasite control. Thus, human evolution of body covering will in future be better artificial coverings.

To the best of my knowledge, in spite of all the half-assed studies to the contrary, the only substance in milk that has been scientifically demonstrated to be bad for you is saturated fat. Full cream milk is about 5% fat by weight. I drink lots of low fat milk - mainly in coffee, since I make my own latte's. The milk I drink is 0.2% fat by weight. This gives me heaps of calcium and protein etc. Incidentally, another food with lots of calcium is any meat that is mechanically deboned. That is because the knives of the mechanical deboner scrape off bone dust into the meat. The bone dust is a great calcium additive.

insane alien speak with tongue most sensible. I get miffed about all those food faddists who claim that food preservatives are all so toxic they are causing us to develop cancer etc, in spite of the toxicology studies showing the contrary. What would you prefer? Sausage with an aproved and safe preservative, or sausage with the toxin produced by the botulinum bacteria? Here is a clue. Botulinum toxin is the most toxic substance ever discovered. About a thousand times more toxic than the worst of the dioxins.

There is just under 2 billion tonnes of carbon dioxide in the Earth's atmosphere. To remove any appreciable fraction of that immense amount is not feasible. Remember, this gas has real weight, and any pumping of the gas up a space elevator has to lift that large fraction a vast distance. We are talking 38,000 kms to get to the point where it has practically speaking no weight. It has to go even further to get to the point where, when released, it will spin off into space.

Here is another query to throw at you guys. Vitamins and anti-oxidants. We know that vitamins are necessary for good health, and we know that they work on the basis of 'enough is enough'. Vitamin C, for example, is needed by the average person at 50 mg per day. If you ingest 51 mg, the extra is just excreted. But what about anti-oxidants? Tomatoes contain lycopenes, that are supposed to be protective against prostate cancer. Does anyone have evidence of a similar rule, showing enough is enough? Is there an optimum amount, with excess either harmful or just excreted?

To big31 What you say is true. However, the reason nutritionists are taking another look at potatoes is that they now realise that the indigestible starch component acts as a kind of dietary fibre. Fibre associated with starch foods acts to lower the GI. The fibre equivalent in potato means it has an effective GI that is much lower than previously realised. The result is that potatoes are filling - both at the time of eating, and for some time after. You simply do not feel hungry for quite some time. The fad diet industry is starting to get hold of this idea. You may wish to read : http://www.associatedcontent.com/article/910247/the_potato_diet_lose_weight_by_eating.html If you need to experience it for yourself, compare a small hamburger with 500 Calories with 5 medium size potatoes (500 Calories). Eat one for breakfast one day, and see how full you feel, and time how long till you are again hungry. Compare it to the other for breakfast another day. I have been puzzled for a long time by the statements that potatoes were fattening (and I do understand the GI argument). The reason for my puzzlement is that about 25 years ago, I read a report on a diet experiment. The researchers took a bunch of people wanting to lose weight, and randomely divided them into two groups. One group was required to eat a pound of potatoes per day, in addition to whatever other foods they chose, and the other group just to continue eating their normal diet. On average, the potato group lost weight while the other gained. Recent reports suggests that nutritionists are again realising that potatoes are not fattening. This is the international year of the potato (no kidding) which recognises its value as a food. Check http://www.coloradopotato.org/colorado_potato_facts_nutrition.php

To yourdad Yes, I meant Calories (or kilocalories). Sorry for the confusion. According to the article I read recently, there are several different types of starch in potatoes, and some are almost indigestible - providing the equivalent of fibre rather than starch. Hence the lower number of Calories than previously understood. Here's what wiki says http://en.wikipedia.org/wiki/Potato "Nutritionally, potatoes are best known for their carbohydrate content (approximately 26 grams in a medium potato). The predominant form of this carbohydrate is starch. A small but significant portion of this starch is resistant to digestion by enzymes in the stomach and small intestine, and so reaches the large intestine essentially intact. This resistant starch is considered to have similar physiological effects and health benefits as fiber: it provides bulk, offers protection against colon cancer, improves glucose tolerance and insulin sensitivity, lowers plasma cholesterol and triglyceride concentrations, increases satiety, and possibly even reduces fat storage (Cummings et al. 1996; Hylla et al 1998; Raban et al. 1994). The amount of resistant starch in potatoes depends much on preparation methods. Cooking and then cooling potatoes significantly increases resistant starch. For example, cooked potato starch contains about 7% resistant starch, which increases to about 13% upon cooling (Englyst et al. 1992)."

There are lots of widely held beliefs out there about food and health, and a lot have been shown to be incorrect with modern science. here are a couple. 1. Salt. Salt causes high blood pressure - right? Actually only right for a third of the people. There is a gene, common in people of African descent, that causes humans to conserve sodium. This means that with salty food, salt builds up in the body and causes high blood pressure. For the majority of us, that does not happen, and salt is not a cause of high blood pressure. How to tell? Easy. Measure your resting blood pressure. Wait 30 minutes. Eat a teaspoon of salt and wait 15 minutes. Measure it again. If you got the nasty gene, you will see a sizeable jump in blood pressure. 2. Potatoes are fattening. Actually, a medium size potato contributes only 100 calories. A young active male will need 3000 calories per day to maintain weight. That is 30 potatoes per day. Of course, if your potatoes arrive coated with fat, this logic goes down the gurgler. Any other myths?

This topic gave me an idea for another interesting topic. Food myths. Gonna start that as a new thread. Anyone joining me?