SkepticLance

Edtharan A few points from your last post. CO2 versus methane. Forests, whether climax or growing, do not produce methane as a net emission. There were some earlier reports to that effect, but further research has shown no net production. In fact, over the past few decades, methane in the Earth's atmosphere has been falling, albeit by a very small amount. Methane is a relatively short term contaminant in the atmosphere. It has a half life of 12 months. This means that, of all methane released today, 75% is gone in 2 years. It oxidises to CO2 and water vapour. CO2 absorption by old forests. Sadly, your earlier statement was incorrect. I used to believe, as you do, that old forests do not sequester carbon. Now I realise I was wrong. Old forests are continuously adding to carbon in soils, and discharging carbon down waterways. All this from plant fragments that fall to the ground. Some become humus, and sequesters carbon in the soil. Some washes to the sea, and a small fraction ends up as deep sea sediment, which is a long term carbon storage. Some gets buried downriver. Carbon in soils is one of the most important forms of carbon storage. It has been calculated, that if the 50% of the Earth's land area that is fully arable gained 2 mm thickness per decade from extra humus, that would take up all the CO2 released by all human activities. Clearly this is not happening, but it indicates the importance of this means of removing carbon. And forests, old and new, are sequestering carbon into soils. With the world growing more verdant, more carbon gets sequestered. Obviously this is not enough to stop CO2 increase, or to stop warming, and I have never suggested it was. But it may be one reason why warming remains linear, even though CO2 emissions continue to increase. I have never argued that negative feed-back mechanisms act to stop warming, at this point in time. My arguments are simply pointed to the uncertainty of future predictions. Since no-one knows what will happen in the future with respect to the balance between positive and negative feed-back mechanisms, how can anyone try for a prediction? Re your comment about warming being non linear. I have explained before why I stick to the past 30 years as the example of warming. It is simply because that is the only time period in which temperature change is utterly dominated by human carbon emissions. The 35 year period before that (1941 to 1976) was one of net cooling. The 31 year period before that (1910 to 1941) was one of warming - but very substantial warming when the CO2 increase was totally insufficient to be the main cause of that warming. If we are to talk about warming caused by human activities, the picture is clear for the period of 1976 to the present, but utterly muddied before that, to the extent that deriving conclusions about anthropogenic greenhouse gas effect is totally unjustified.

Another calculation. 500 trillion tonnes of copper in the crust. Sayonara said 15 million tonnes mined per year. If only one part per 100,000 is available to exploitation, that is a total of 5 billion tonnes. At 15 million tonnes per year, that is a supply lasting well over 300 years. I accept that finite means finite. However, the supply of the common elements, assuming a reasonable degree of technological development in extraction methods, should last us well into the future. Beyond 300 years, I am not prepared to predict what the world will be like or what our descendents will need in the way of resources. I believe, however, that for most resources, that humanity will cope. Perhaps in 300 years, there will be recycling technology of close to 100% efficiency? Perhaps we will be pumping magma from beneath the Earth's crust and removing minerals and energy, before pumping it back? Perhaps we will be mining the asteroids??? Perhaps we will have developed a 'perfect' means of extracting everything we require from seawater??? Any predictions beyond 300 years will be science fiction, and in that field almost anything goes.

To Nicks A lot of these questions depend on what equipment and skills are available post-holocaust. I have been assuming some kind of return to medieval situation, which makes antibiotic manufacture a real case of 'by guess or by God.' In the course of my work, I often get given samples of various moulds, and get asked what they are. I check them microscopically, which is good enough to derive the genus (most of the time). However, if the species is required, I send the sample off to a laboratory in the USA, which has proper nucleic acid sequencing equipment. A few species of mould are more or less identifiable under the microscope, but even for these few, it is tricky. I remember about 25 years ago working on Trichoderma viride for the timber industry, where it is a problem infection on wood. We were puzzled by some research results that showed that this mould in Finland was easily controlled with methylene bisthiocyanate. The NZ Trichoderma viride, though, laughed at this chemical. That was before good nucleic acid sequencing technology was available. Since then, the answer has been apparent. What we thought was all Trichoderma viride is not actually one species. There are about 100 different species, all of which were originally classified as Trichoderma viride. The point here, is that without advanced technology, when you cultivate a mould, you simply do not know what mould it is. It might be something well able to produce penicillin in quantity, or it might produce nothing. Far better to obtain a sample of purified Penicillium chrysogenum from a specialty laboratory supplies source, and stay with it.

Swansont That may be correct. Operative word - 'may'. We simply do not know what the future holds. Lots of ideas exist, but only time will tell. Will positive feed-back mechanisms be more potent than negative? I do not know. You do not know. We can only guess, and the expressed guess is usually a reflection of a person's political viewpoint, rather than a reflection of good science.

To Nicks About insulin. The web site you quoted is about a form of insulin which they are selling, called recombinant. I will try to explain. The original insulin was pig insulin. At meat works, when pigs were cut up, the pancreas of each pig was set aside to permit the insulin to be extracted. It worked, and helped diabetics, but had side effects. Some side effects were serious, and long term diabetics injecting pig insulin would often go blind, or have problems leading to limb amputation etc. Not nice! It has long been known that human insulin would be better, but no-one was prepared to cut up thousands of people to extract their pancreas! The breakthrough was the isolation of the human gene that makes insulin. This was inserted into a bacterium, and that bacterium was cultured, and the insulin it made extracted, purified, and placed in vials for injection. This was also a much cheaper way to get insulin, and diabetics have benefited from the much lower rate of side effects ever since. To do this post-holocaust would require getting hold of some of these genetically modified bacteria, which I suspect would not be easy. In fact, given another 50 years or so, a great many drugs will be made in a similar way. Post-holocaust, you could make them if you managed to salvage some of the appropriate GM organisms. Again, assuming it is post-holocaust, you are not going to be able to produce purified pharmaceutical grade drugs, even with the right bacteria or moulds. Something like my suggested Penicillium soup would be the only way to go.

YT You can argue that everything is finite, and you would be correct. However, everything is also relative. And relative to what humanity has so far extracted, the resource is still enormous. At least for common elements like copper and lead, though as Sayonara pointed out, it may be more difficult for rarer products like Platinum, Tellurium, Iridium etc.

To Edtharan Actually I agree with you that my wording of 10 million wind turbines was lousy, and misleading. Sorry about that. My recollection of my thinking at the time was related to those people who think that vast quantities of wind turbines is the total solution to global warming, but I did not make that clear. Of course, using wind to generate power is part of the solution, but only part. And probably a small part. Your points 1 to 4. I tend to agree with points 1 to 3. Of course the world is warming, and the main cause is human activity. This has been the situation for the past 30 odd years. Before that, the warming is probably better explained as a return to 'normal' conditions after the Little Ice Age. I have to dispute your item 4, at least on the 30 year time scale, because over that time the temperature increase, with minor fluctuations smoothed out, has been approximately linear. If warming is to accelerate, then carbon emissions have to accelerate at an even greater rate. This may happen, or it may not. Predictions are dangerous. Your description of the effects of melting permafrost is hardly new. It has been discussed on this and other similar threads over a long period, and I do, in fact, understand it. It is a classic example of a proposed positive feed-back mechanism. You may recall that I accept that such mechanisms do exist. You may also remember that I pointed out that negative feed-back mechanisms also exist. For example : the warming of the world will lead to more rapid plant growth. Thus more CO2 absorbed. Try reading : http://www.impactlab.com/2008/06/09/scientists-surprised-to-find-earths-biosphere-booming/ This is one of many possible negative feed-back mechanisms. We do not know if positive or negative feed-backs will dominate in the future, and the idea that positives will be the main effect is common among global climate change pessimists. They may be right, but we do not know.

To Dr P The strongest fibre in terms of tensile is buckytubes. However, we are still a long way off making suitably long continuous fibres, and as soon as someone tries to 'glue' buckytube fibres together, the tensile plummets.

Edtharan You may be reading into my earlier posts some things I did not mean to say. If I calculate a total of (say) a trillion tonnes of an element in the Earth's crust, I am not suggesting that anyone will mine the entire Earth's crust to get that trillion tonnes. The number is there to give an upper limit to the amount potentially available. Of course no one is going to mine the entire crust. If the number is a trillion tonnes, then there may be a total of one part in 100,000 mined over the next 10,000 years. Definitely not the same as total exploitation. Even that is 10 million tonnes, which is hardly inconsiderable. Nor will we be diving into mass mining procedures which will destroy entire ecosystems in the near future. Developments will be slow, and will evolve into new technologies that will permit extra extraction of essential materials. The current trend is towards ever more careful methods with a view to conserving the natural environment, and this trend will probably continue. The main point of my last posts on this topic have been in response to the suggestion that humankind will run out of essential elements, such as copper or lead. I merely pointed out that these materials are not in limited supply. The only limiting factor is the degree of ingenuity that can be put into obtaining what is needed, with appropriate environmental safeguards, of course. For something like Lithium from the ocean ; - The concentration is 0.2 grams of Lithium per tonne of seawater. There are E18 tonnes of sea water, meaning an essentially unlimited quantity of Lithium. To extract a tonne of Lithium ( assuming 100% efficiency) requires 5000 tonnes of seawater to be processed. This amount of seawater a volume of seawater roughly 17 metres by 17 metres by 17 metres. For 1000 tonnes of Lithium, the amount becomes a cube of 170m by 170m by 170m. While large scale exploitation would involve much more volume than this, it too would literally be a tiny drop in the ocean, and should do little in the way of harm to ecology. Even if efficiency is only 10% and 10,000 tonnes of Lithium are made each year, the amount of seawater required to be processed would be only 500 parts per trillion per year. Hardly a big impact on marine ecology.

The gene for spider silk protein manufacture has been successfully isolated, and inserted into a suitable plant. That plant now makes a small amount of spider silk as part of its metabolism. However, that is still a long way from being able to use the protein to make fibres. If it is ever achieved, it would be a great step forwards, since spider silk has the second greatest tensile strength of any fibre known.

A private message for Sayonara, because he rather unfairly criticised my 'lack' of ability to use logic on another thread, and then closed the thread before I could defend myself. Sayonara, please check the following. http://www.newscientist.com/article/dn14647?DCMP=NLC-nletter&nsref=dn14647 Everyone else, please ignore, and my apologies for posting something so off thread, but I was left previously feeling very hurt and very angry.

To Nicks All good questions and comments. I have been more or less addressing the original question, which relates to making penicillin in the kitchen. On this basis, it is not possible to make an equivalent of pharmaceutically pure product. Instead, the best we could do is the equivalent of herbal remedies in that it will have massively variable active ingredient, massively variable efficacy, massively variable levels of impurities, and a final result on the sick person that has to be described as massively variable. That is the sad reality of operating when good science and precise technology are not available. In our doomsday scenario, sterility is still possible. Relatively crude apparatus can be used to build a large equivalent of an autoclave (pressure cooker). The culture medium would have to be something like congealed soup, since more sophisticated materials would not be available. However, mould should grow perfectly well on such a material. Most moulds are not actually toxic, meaning that crude filtering would be enough, and any impurities in the filtrate would not harm the patient. Probably taste awful, though!

To dichotomy I am not sure that 20 years would be enough. The type of crime that we really want to stop is serious assault or murder of children. New anti-spanking laws are really not going to help here. After all, serious assaults and murder have been seriously against the law for ever, and with heavy penalties. No doubt the law and the penalties have stopped lots of child abuse of that type in the past, but not all. Adding a penalty against minor physical punishment of children is not going to stop the serious offenses. And do we really want to punish parents who only spank, without any more serious abuse? In any absolute term, there is no such thing as a good parent - just a whole lot of imperfect humans who love their kids and do their best to raise their kids in the best way they know how. I regard these loving people as close enough to 'good parents'.

An elephant or a whale. You need a heavy calibre bullet to killem.

To Nicks If you can grow a pure culture of Penicillium chrysogenum in sufficient quantity, and I mean a bath full of the stuff, you can prepare a crude solution that might cure an infection. Once you have sufficient mass of the mould, you take it from the culture, and grind it and filter it to remove the trash. The sick person who drinks the resulting disgusting brew may get enough penicillin to save his/her life. No guarantees here, and you would need to be fairly desperate. Personally, I would rather go to my doctor and get a prescription for the good stuff!

I dunno what will evolve. But I could suggest a nice artificial cover. For best thermal insulation, you need the best method of trapping air. Perhaps a three dimensional network of buckytubes combined with Kevlar, which would give insulation, flexibility, and a bullet proof jacket!

To dichotomy Was the law a failure? Depends of which goal you are measuring it against. Those who made the law said it would cut down on serious violent crime against children, and emphasized that it was NOT directed against good parents who used mild physical discipline. Result : Serious violent crime against children, after 2 years, is still as high as ever. A number of good parents who used mild physical discipline have been through the court system and suffered penalties. What do you conclude?

Stevo Here in New Zealand you can, in theory, go to jail for spanking a child. For many years we had a law that said that physical force against a child was assault, with all the normal penalties for assault including jail - but had the clause attached that this did not apply to reasonable force used for disciplinary purposes. Then about two years ago, a bleeding heart liberal took a bill to parliament (and won a law change) rescinding the clause permitting reasonable force. The only concession they made to common sense was a clause saying the police had the right to overlook such 'crimes' if they were trivial. The whole reason for this change in the law was to stop serious offenders who claimed that they were applying discipline. The result has been zero. Just as many serious assaults of children have occurred as before, if not even more of them! Trivial cases have made it to court. Several parents have been charged and been required to suffer penalties. A recent case was a man who flicked his son's ear to stop his son from yelling and running around making a nuisance of himself in a public place. He was charged, convicted, and sentenced to community service. The sad thing is that the law change has not worked. Serious offenses against children continue as before. People who assault and even murder children in their care do not stop because the law says it is wrong. The only people who get punished now, who would not have been punished under the old law, are good parents applying minimal punishment.

Hello Nicks. I do not think I can answer all your queries. Certainly, the highest yielding strains of Penicillium will be restricted to the drug companies. Unless you know someone who is prepared to break all the rules, you are not going to lay your hands on any of those. However, the first Penicillin was made from 'natural' strains of Penicillium. As long as you do not insist of high purity drug, a crude material could be prepared from 'natural' mould. Safety? I would not use such a preparation as long as a modern source was available. Only in extreme circumstances, such as after a nuclear war and collapse of civilisation would I even start experimenting. Freeze dried speciments can survive many years without refrigeration. I buy a few occasionally from a local source, and they come in glass vials that have to be broken to access the sample. I then have to grow it on suitable culture medium to get an actual mould sample.

To Sayonara In our previous posts, I was discussing your earlier example of lead and copper, and other comparable products. I agree that Platinum and Tellurium are somewhat different. Substitution will happen, in spite of your pessimism about that, but to what extent, I am not prepared to predict. We will probably continue to need some of each. There is about 50 billion tonnes of Platinum in the Earth's crust (and only about 50,000 tonnes in the seas), but in the crust, it is not evenly distributed. It is found in much higher concentration associated with ultramafic materials in igneous rocks. Even in those deposits, it is still at low concentration, except for a few richer ores, which are in the process of being exploited. Extraction of Platinum from poorer ores is definitely a possibility. However, that is a development not yet close to fruition, and I am not prepared to make predictions. One source for possible optimism is the new technology for extracting microcrystalline materials. Currently, the research here is on gold, which is present in certain hydrothermal areas in microcrystalline form, widely dispersed, but in relatively very large amounts. Once it can be extracted, the amount available will increase and the price will drop. Platinum also appears to exist in this form, and alongside the gold. If so, the amount available may be more than we realise. I admit that this is very speculative at this stage. Another technology that is being developed, though more for gold at present, is the use of bio-concentrators. For example : genetically modified plants able to grow in the tailings of gold mines, and which concentrate the gold in their leaves. There are some biologists who believe that certain deep dwelling bacteria and archaeans, many kilometres below the Earth's surface, may act to concentrate Platinum, and other materials. This remains to be proven. If so, there will be genetic material that can be harvested and used to modify plants to act as bio-concentrators. Another development under way is from Iceland, where researchers are experimenting with deep drilling to obtain access to ultra-high temperature and ultra-high pressure water. This water will be used mainly as a source of energy, but it is also laden with minerals. The researchers plan to experiment with gradual cooling of the water to separately deposit the various minerals that are dissolved. I admit that these developments are very uncertain right now. Platinum may become more available and cheaper as the result of current technological developments. or those developments may come to nothing, and Platinum will become less common and more expensive. Time will tell. If Platinum remains rare and expensive, humanity will have to learn to live without it, and find other ways of achieving similar ends. Ditto for Tellurium. I doubt that such a shortage will slow human progress too much. People are just too damn clever at finding ways to achieve desired goals.

Sayonara I understand your point. I just don't agree with it. The history of mineral exploitation has always followed the general rule that rich ores are first exploited, and then poorer ores. As time passes, poorer and poorer ores are resorted to. The good thing is that there are a hell of a lot more tonnes of metal in the poorer ores than the richer, simply because poorer ores are far more abundant, and this means that, when we learn to exploit these poorer ores, the substance becomes much more abundant. This is part of the reason that the modern world is so rich by comparison with any time in the past. We have enormously greater amounts of resources. If your thesis is correct, then it means that a very long term trend towards exploiting poorer ores and finding we have more and more of the resource - well that trend will have to reverse. I happen to believe that, because technology continues to get more potent, the long term trend will continue, and we will not run out of resources.

To Sayonara I suspect I am more opimistic than you about the human ability to apply ingenuity, and I think we will, indeed, develop ways that are not too costly to extract lead etc from lower purity ores. An alternative that always exists is substitution. I mentioned the incredible abundance of Titanium. That is an amazing element with enormous potential value. Iron is another material of incredible abundance - the fourth most abundant element at 5% of the crust by weight. It should NEVER run out. If we cannot get as much lead out of the ground, we will move to other materials. For example : as lead/acid batteries become unavailable, we will substitute with Lithium. Lithium is present in enormous amounts in the ocean. 25 billion tonnes of it. The ability to extract Lithium from seawater has just begun and the first small scale pilot plant is now operating. OK. The amounts extracted are still very small (just a gram a day so far), but will grow as the technology improves. http://goliath.ecnext.com/coms2/gi_0199-238828/Saga-University-institute-starts-extracting.html The history of the past 500 years is one of continuous increase in abundance of materials to drive our civilisation. Technology will, if anything, accelerate its development over the next 100 years, and our ability to obtain the massive abundance of elements in the Earth's crust and in the ocean will just improve. Ok, call me a shameless optimist, but I cannot see that improving technology will result in serious shortages when the elements are so abundant.

To Sayonara I have to tender an apology. I double checked my figure for copper, and it is, in fact, 50 parts per million in the Earth's crust. So you will need to revise my figures for copper upwards 50 fold. Lead is 14 parts per million. This means about 150 trillion tonnes in the Earths crust. If we assume that only one part in 100,000 will ever be extractable, this means there is a potentially available resource of well over a billion tonnes of lead. Only a couple of million tonnes dissolved in seawater, though. Of course, none of these resources are evenly distributed, and people will always seek out the highest concentrations. However, given a reasonable amount of technological progress, and the continuing ability to extract lead from lower grade ores, we should not run out in a hurry. However, as before, I cannot guarantee the price will not rise. One that interested me. Since I was looking up relative abundance in the Earth's crust, I noticed this. Titanium is amazingly abundant! It makes up a full 0.44% of the Earth's crust. Titanium is an incredibly useful metal, and once we learn to extract it more efficiently, it will no doubt become a substantial driver of human progress.

To Sayonara In theory, you are correct. However, the numbers are so high that this 'correctness' is meaningless for any foreseeable future. Take the element you mentioned - copper. The Earth's crust is about E22 kg in mass. Copper (as far as we can tell) makes up about one part per million by mass of the Earth's crust. That is a total of 10 trillion tonnes. That is way more than humankind is ever likely to need for any predictable future time - many powers of ten more. Of course, it is a moot point to decide what fraction of that 10 trillion tonnes humans can ever exploit. Still - knock off a few zeros and we are still rolling in copper. Currently we exploit high purity rich ores. There is a rough law of ten (not actually ten - it varies a lot) which says that each time you move from high grade to lower grade ores, the available quantity increases. If we move to two grades lower, the amount increases by 100 (although, as I said, this conversion factor is highly variable - depends on the mineral, and the kind of resource, but I hope you get the principle). The oceans contain some 400 million tonnes of copper dissolved in seawater. It would be difficult and expensive to extract - but a future technology might be able to do it. Short summary - we are not likely to run out. The worst will be an increase in price.

To Mr Skeptic The 'idiot' factor surrounding the addition of iron is simply lack of data. We know that iron stimulates plankton growth. We do NOT know if that translates into carbon removal. To do that, the increased biomass would have to somehow end up in long term storage, so that the carbon is not recycled. It is possible that some would end as deep sea sediment, but there is no data to confirm or deny that. In addition, we need to be aware of possible deleterious ecological effects. Adding heaps of iron, with the subsequent plankton blooms would almost certainly have unpredictable effects on the wider ecology. Until we have a LOT more information, such ideas have to be put into the crackpot hat.