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Post by propman on Aug 27, 2019 10:21:12 GMT
We seem to have a increasinging tendency to attack scientific method. Science can never discover the truth. It's based to a large degree on the Popper falsification hypothesis. We postulate a theory, we compare it with the empirical data, we adjust the theory, we compare again. It's an iterative process. We never attain the absolute truth since that is a meaningless concept but we do have an idea what is conditionally true (based on current data, with some form of error bounds) and what is definitely false.
Now regard to climate change. We know that the planet can only dissipate heat through IR radation. We also know that every economic process requires energy usage and that all energy usage will generate waste energy. This follows from the Second Law of Thermodynamics. In any process we start of with low entropy, concentrated energy, that is used to do some work and we are left with high-entropy, waste energy (typicaly waste heat). The high entropy waste heat cannot be radiated into space due to it wavelength. Therefore the entropy of the planet can only rise and that statement is independent of technology. It's a fundamental physical law. So it's virtually impossible to argue against the idea that human energy usage will not cause the temperature of the planet to rise. You'd have to violate the 2nd law for that not to occur...
For the record I believe that on the balance of probabilities there is sufficient evidence to conclude that we need to take significant action now on a concerted basis.
However if you were correct that no hear could escape the atmosphere we would have perished long ago. Not only was the planet hotter earlier in its life, but the amount of solar heating is significant so without any additions from man we would have heated up however hot is required to allow loss of heat before there was life on earth. Carbon dioxide and other greenhouse gasses are only important as they reduce the loss of heat to space.
Popper also made it clear that the scientific community generally lurches from one state of orthodoxy to another as the tendency is not to believe a change is required past the point when an objective assessment requires a change.
The only reason to postulate disaster if we don't take action soon is that there are feedback loops that will kick in to enhance the warming and which will not be reversible. These include the greater solar warming of bare earth rather than ice and hence loss of ice area will increase warming, and warmer water will release carbon dioxide to the atmosphere. Both have been demonstrated but neither has been quantified as the amounts to date are too small to conclusively quantify based on changes to date. That is why there is still doubt over the timescale for making the adjustments.
In addition, even measuring the changes is far from subjective. Population centres generate heat. Weather stations have generally been set up close to the edges of population centres and these have generally expanded around them. Global warming is based on extrapolating the heat from the centres across the globe. This includes huge areas with very few data points. Warming has not been uniform and the total to date is less than the natural year to year fluctuations. So it is only with the evidence of many data points and an estimate of what the warming would have been if we strip out the effects of urbanisation around them that we have a picture of average global temperatures. These processes are subjective and scientists differ on the correct interpretation. Finally, the warming impacts would explain a much larger movement than any have assessed has happenned. hence models need to add in cooling effects to account for the actual observations. These include increased cloud formation.
I am many years out of date having not researched for 30 years and not kept up to date with the huge amount of research that has happened during this period, so I am far from authorative on the current weight of evidence. But don't be fooled to think that there isn't a huge amount of pro-anthropomorphic Climate Change due to scientists and others with a vested interest in the outcome. It is a fact that you cannot readily get published in serious (peer reviewed) journals if you go against the orthodoxy and funding is very limited (contrary to popular opinion, the energy industry is very sparing on funding compared with the climate activists). So even if anyone could read all the papers on the subject, this would not be representative of the entirety of views in the scientific community and there is not a balance of support for all potentially relevant lines of research including those supporting a longer less dramatic timescale for the changes.
So I do believe that the future effect of our use of fossil fuals and release of large quantities of the more potent greenhouse gases is well understood. That said, it seems likely we are making a difference and there is a very strong case for developing alternative technologies and employing them wherever we can. I am a huge advocate in investing of taking much greater notice of the less likely but more significant consequences that arise in the tails of the potential distribution of investment outcomes. So I agree that taking action to itigate potential disasters at a current cost is justified. But in investment the mainstream takes too little notice of the tail impacts so I am not surprised that people are generally split between the climate warriors and those unconvinced. We are not equipped to make objective assessments individually and I believe institutionally.
- PM
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Post by samford71 on Aug 27, 2019 20:03:48 GMT
We seem to have a increasinging tendency to attack scientific method. Science can never discover the truth. It's based to a large degree on the Popper falsification hypothesis. We postulate a theory, we compare it with the empirical data, we adjust the theory, we compare again. It's an iterative process. We never attain the absolute truth since that is a meaningless concept but we do have an idea what is conditionally true (based on current data, with some form of error bounds) and what is definitely false.
Now regard to climate change. We know that the planet can only dissipate heat through IR radation. We also know that every economic process requires energy usage and that all energy usage will generate waste energy. This follows from the Second Law of Thermodynamics. In any process we start of with low entropy, concentrated energy, that is used to do some work and we are left with high-entropy, waste energy (typicaly waste heat). The high entropy waste heat cannot be radiated into space due to it wavelength. Therefore the entropy of the planet can only rise and that statement is independent of technology. It's a fundamental physical law. So it's virtually impossible to argue against the idea that human energy usage will not cause the temperature of the planet to rise. You'd have to violate the 2nd law for that not to occur...
....
However if you were correct that no hear could escape the atmosphere we would have perished long ago. Not only was the planet hotter earlier in its life, but the amount of solar heating is significant so without any additions from man we would have heated up however hot is required to allow loss of heat before there was life on earth. Carbon dioxide and other greenhouse gasses are only important as they reduce the loss of heat to space. .....
- PM
Of course temperatures have varied over the 4 billion year history of the planet. Plate tectonics, cosmic bombardment, the impact of life (particularly plant life) have all has a fundamental impact on the planet's temperature. We are very fortunate that we are situated in a habitable zone that has been able to absorb such effects. Venus was similar to us in it's early period but eventually succumbed to an runaway greenhouse effect. Mars also early on had running water and an atmosphere but didn't have the gravitational pull to maintain it. Such long-term changes, however, aren't really relevant to the current situation. Nor are the shorter-term (by geological standards) climate effects caused by standard perturbative orbital changes.
My point is not really about carbon dioxide or greenhouse gases either. The Earth has only one mechanism for releasing heat to space, and that’s via (infrared) radiation. The problem is that every economic process uses energy in some format. The energy is high-grade, concentrated, low entropy energy. After doing some form of "work", that energy is expended but some element of waste energy is always left over. That waste energy, thermal in nature, is high-entropy and diffuse and cannot be easily got rid of. You might be able to reuse some of this to do useful “work,” but at very low thermodynamic efficiency. So if you want to use high-grade energy in the first place (which we do), having high-entropy waste heat is pretty inescapable. Technology can reduce that waste heat but having some form of waste is guaranteed since the 2nd Law requires the entropy of the system to rise. Now of course we can try to offset that high entropy energy by doing something to increase the rate of loss of radiation to space (blow a hole in the atmosphere say) or we can try to decrease the amount of solar flux hitting the planet (stick a massive mirror in orbit) but we've just moved into the realms of sci-fi.
The basic problem is that economic growth based upon ever increasing use of energy (which is by construction an exponential growth function) is incompatible with a finite resource system (a.k.a the Earth). At some point, which to be fair is hard to define, we run the risk of tipping the sytem into a cascading change. We have no idea what the outcome of such a rapid change might be. We can, however, look back and see that many previous human societies have gone out of business due to rapid environmental change. Worse, the complexity/sophistication of the society seems to be no protection against such changes. In fact, sophistication may make that society more vulnerable since such complexity often begets fragility.
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Post by martin44 on Aug 27, 2019 22:04:08 GMT
....
However if you were correct that no hear could escape the atmosphere we would have perished long ago. Not only was the planet hotter earlier in its life, but the amount of solar heating is significant so without any additions from man we would have heated up however hot is required to allow loss of heat before there was life on earth. Carbon dioxide and other greenhouse gasses are only important as they reduce the loss of heat to space. .....
- PM
Of course temperatures have varied over the 4 billion year history of the planet. Plate tectonics, cosmic bombardment, the impact of life (particularly plant life) have all has a fundamental impact on the planet's temperature. We are very fortunate that we are situated in a habitable zone that has been able to absorb such effects. Venus was similar to us in it's early period but eventually succumbed to an runaway greenhouse effect. Mars also early on had running water and an atmosphere but didn't have the gravitational pull to maintain it. Such long-term changes, however, aren't really relevant to the current situation. Nor are the shorter-term (by geological standards) climate effects caused by standard perturbative orbital changes.
My point is not really about carbon dioxide or greenhouse gases either. The Earth has only one mechanism for releasing heat to space, and that’s via (infrared) radiation. The problem is that every economic process uses energy in some format. The energy is high-grade, concentrated, low entropy energy. After doing some form of "work", that energy is expended but some element of waste energy is always left over. That waste energy, thermal in nature, is high-entropy and diffuse and cannot be easily got rid of. You might be able to reuse some of this to do useful “work,” but at very low thermodynamic efficiency. So if you want to use high-grade energy in the first place (which we do), having high-entropy waste heat is pretty inescapable. Technology can reduce that waste heat but having some form of waste is guaranteed since the 2nd Law requires the entropy of the system to rise. Now of course we can try to offset that high entropy energy by doing something to increase the rate of loss of radiation to space (blow a hole in the atmosphere say) or we can try to decrease the amount of solar flux hitting the planet (stick a massive mirror in orbit) but we've just moved into the realms of sci-fi.
The basic problem is that economic growth based upon ever increasing use of energy (which is by construction an exponential growth function) is incompatible with a finite resource system (a.k.a the Earth). At some point, which to be fair is hard to define, we run the risk of tipping the sytem into a cascading change. We have no idea what the outcome of such a rapid change might be. We can, however, look back and see that many previous human societies have gone out of business due to rapid environmental change. Worse, the complexity/sophistication of the society seems to be no protection against such changes. In fact, sophistication may make that society more vulnerable since such complexity often begets fragility.
Im sorry but that statement is contradictory to your argument.... when you say "we can look back" .. look back to when?. i doubt the previous human societies you refer to went out of business because of rapid environmental change due to "Burning fossil fuels" .. "Combustion engines"... "Deforestation" or (sarcastically) plastic straws . .. i would suggest "They" ... i'm assuming here but "Egyptians?" Mayans? etc etc.. went out of business due to natural environmental change, rivers change course (Nile, 7 times in 5000 years) due to silting, deserts change there natural progressive course, (Sahara) .. To be quoting our so called understanding of planetary evolution and then comparing it to climate change today is quite frankly ridiculous. And your statement "My point is not really about carbon dioxide" I have always been under the impression that global warming is all about C02..... The most important gas in the whole universe, which without, there is nothing. Im certainly no expert, far from it, but from a layman's perspective, your argument does not hold up.
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michaelc
Member of DD Central
Say No To T.D.S.
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Post by michaelc on Aug 27, 2019 23:10:36 GMT
What irks me is that so many people are so sure about something that they label those who dare to question and spark debate as "deniers".
Debate is always healthy.
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Post by bracknellboy on Aug 28, 2019 8:30:12 GMT
....At some point, which to be fair is hard to define, we run the risk of tipping the sytem into a cascading change. We have no idea what the outcome of such a rapid change might be. We can, however, look back and see that many previous human societies have gone out of business due to rapid environmental change. Worse, the complexity/sophistication of the society seems to be no protection against such changes. In fact, sophistication may make that society more vulnerable since such complexity often begets fragility.
Im sorry but that statement is contradictory to your argument.... when you say "we can look back" .. look back to when?. i doubt the previous human societies you refer to went out of business because of rapid environmental change due to "Burning fossil fuels" .. "Combustion engines"... "Deforestation" or (sarcastically) plastic straws . .. i would suggest "They" ... i'm assuming here but "Egyptians?" Mayans? etc etc.. went out of business due to natural environmental change, rivers change course (Nile, 7 times in 5000 years) due to silting, deserts change there natural progressive course, (Sahara) .. To be quoting our so called understanding of planetary evolution and then comparing it to climate change today is quite frankly ridiculous. .... Im certainly no expert, far from it, but from a layman's perspective, your argument does not hold up. Actually it is your extrapolation of the OPs statements that is illogical. There was very clearly no implication, intended or otherwise, that those prior societies had gone out of business necessarily due to human activity. The point being made was simply as stated: that history may be able to tell us something about the impact on society of rapid environmental change, regardless of the cause of that change.
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Post by martin44 on Sept 2, 2019 22:32:48 GMT
Im sorry but that statement is contradictory to your argument.... when you say "we can look back" .. look back to when?. i doubt the previous human societies you refer to went out of business because of rapid environmental change due to "Burning fossil fuels" .. "Combustion engines"... "Deforestation" or (sarcastically) plastic straws . .. i would suggest "They" ... i'm assuming here but "Egyptians?" Mayans? etc etc.. went out of business due to natural environmental change, rivers change course (Nile, 7 times in 5000 years) due to silting, deserts change there natural progressive course, (Sahara) .. To be quoting our so called understanding of planetary evolution and then comparing it to climate change today is quite frankly ridiculous. .... Im certainly no expert, far from it, but from a layman's perspective, your argument does not hold up. Actually it is your extrapolation of the OPs statements that is illogical. There was very clearly no implication, intended or otherwise, that those prior societies had gone out of business necessarily due to human activity. The point being made was simply as stated: that history may be able to tell us something about the impact on society of rapid environmental change, regardless of the cause of that change. That's a valid statement and i'm happy to concede that your evaluation is pertinent, one reads it one way and others read it another. Hopefully everyone is on the same page ie. something drastic has to be done by all, the biggest challenge is getting all on board, which i fear will prove to be impossible.
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Post by martin44 on Sept 2, 2019 22:48:32 GMT
Only a Buffon would suggest that climate change isn't taking place. Climate change is supposed to be wide variation in temperature year to year but with average temperatures moving upwards. That's beyond doubt. Feel free to disagree on the cause. Personally I am happy to see a little less waste. Do people really need that many clothes? (particularly women) I include myself in that. Although I buy mine mainly second hand on eBay.....I am so tight! Why waste your time on ebay? (Bidding?.. Postage?.. waiting for delivery?.. Having to be "In"... i get many from the extraordinary amount of charity shops that have taken over the high streets... 
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littleoldlady
Member of DD Central
Running down all platforms due to age
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Post by littleoldlady on Sept 3, 2019 6:30:24 GMT
I am a denier.
I do not deny that climate change is happening, nor that it is at least partially (mainly) caused by human activity.
I deny:
1) That the planet is at risk. the planet will be fine. It has already cycled through ice ages and warm periods much hotter than anything forecast for the next century or two. Human civilisation is not the same thing as the planet.
2) That there is anything significant more that the UK can do. Our share of emissions is so small - c1% or so - that any reductions will be meaningless. the only thing we can do is to set an example, which we are already doing, but nobody is responding. Germany panicked after Fukushima and is building 18 coal fired power stations. China increases emissions each year by more than our total. Most of our competitors see our reductions as an opportunity for them to gain a competitive advantage. Extinction Rebellion should up sticks and go (walk) to some of these countries to demonstrate.
In fact, global warming might be essential for the long term future of intelligent life on Earth. As things stand after humanity has become extinct any future intelligent specie could not develop an industrial civilisation in the way we did because we have used up all the easily accessible fossil fuels. What is need is a few million years of high temperatures to lay down a new supply of fuel for such putative intelligent beings to exploit. But I admit this is certainly taking the long view!
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Post by Deleted on Sept 3, 2019 13:26:10 GMT
The whole "we only do 1%" so why bother argument is a little weak as it fails to account for the manufacturing of products we have outsourced to Chinese plants. The maths gets pretty complicated but some good sources are here
Since we have legally agreed to get from 1% to 0% I still think it will some massive stretch and will have significant investment opportunities. After all, while our oil production continues to fall we will need to reduce our net oil consumption significantly and this will then benefit other countries oil production by reducing it.
I agree the planet will be fine, it is just humanity that will be impoverished (oh and all the animals).
Still, if we 1% all just say let the others do all the work eventually no one will do anything. I suspect the "prisoner's dilemma" strategy shows you what to do.
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Post by propman on Sept 3, 2019 14:06:31 GMT
The whole "we only do 1%" so why bother argument is a little weak as it fails to account for the manufacturing of products we have outsourced to Chinese plants. The maths gets pretty complicated but some good sources are here
...
Still, if we 1% all just say let the others do all the work eventually no one will do anything. I suspect the "prisoner's dilemma" strategy shows you what to do.
I thought that Pareto equilibria have been well understood for some time and show that generally you don't get the optimum result that a combined strategy would produce.
Re your original point, it was never suggested that we would not have a carbon impact if you include the impact of carbon produced elsewhere for our benefit. It is thus likely that much of the saving will be at the expense of others increasing their footprint by more than we reduce ours. This is even to some extent the case for all countries as there is significant carbon not allocated to anyone by theusual methods.
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travolta
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Post by travolta on Sept 3, 2019 14:39:31 GMT
Experience from investing in P2P has left me with little or no altruism .
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Post by bracknellboy on Sept 3, 2019 14:42:09 GMT
Experience from investing in P2P has left me with little or no altruism . what about money :-)
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Post by Deleted on Sept 3, 2019 15:34:20 GMT
As Bracknell says, what about the money. The logic requires you to take sides, do nothing or do something. If you believe that the Paris agreement will have effects on the economy you logically should invest to take any benefit from it.
If you take a more sophisticated view, that is that you want to keep enjoying the planet while you are alive then you might also like it to stay nice for you. That is not an issue of altruism but of sheer self-interest.
Your experience with P2P should not influence you one way or another. A study of the basic science and the economics that flow from it suggest that taking it into account for both your wallet and your own well being is a sensible action. Denier or not, please take it seriously.
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Post by Deleted on Sept 3, 2019 15:38:26 GMT
Sounds a bit like the argument that "if others stick their heads out of the train window so should you". If all it took was discussion to change something the world might be a different place, but as well as words, and placards you also need actions. Those actions will eventually be to not trade with countries that refuse to limit CO2 generation, just see how easily Macron began threatening Brasil with that only a couple of weeks ago, it will come. It is going to be a bumpy ride.
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cb25
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Post by cb25 on Sept 3, 2019 16:14:08 GMT
Sounds a bit like the argument that "if others stick their heads out of the train window so should you". If all it took was discussion to change something the world might be a different place, but as well as words, and placards you also need actions. Those actions will eventually be to not trade with countries that refuse to limit CO2 generation, just see how easily Macron began threatening Brasil with that only a couple of weeks ago, it will come. It is going to be a bumpy ride. Given the developed world is quite happy to trade with countries that aren't democratic (e.g. China), I can't see a refusal to reduce CO2 will cause much alarm as long as the price is right (i.e. low). I also can't see people being willing to give up their current lifestyle (flying, cars, consumerism, ..) at all easily.
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