Riedquat Posted January 23, 2014 Share Posted January 23, 2014 Eh? Nonsense. A positive feedback mechanism will amplify change in a positive direction. A negative feedback mechanism will amplify change in a negative direction and a buffering mechanism will keep things stable. No, a positive feedback mechanism is one that amplifies change, a negative feedback one that damps it out. Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 Eh? Nonsense. A positive feedback mechanism will amplify change in a positive direction. A negative feedback mechanism will amplify change in a negative direction and a buffering mechanism will keep things stable. No. That's a basic misunderstanding. Positive feedbacks amplify changes; negative feedbacks damp down changes. Wikipedia has some good entries on the topic: http://en.wikipedia.org/wiki/Positive_feedback http://en.wikipedia.org/wiki/Climate_change_feedback Link to comment Share on other sites More sharing options...
ntb Posted January 23, 2014 Share Posted January 23, 2014 Ok, my bad. What I'm trying to ask is if we have a positive feedback mechanism to amplify the warming effect of CO2 i.e. increased water vapour in the atmosphere, what overrode it in the opposite direction during historical periods that CO2 decreased? Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 Ok, my bad. What I'm trying to ask is if we have a positive feedback mechanism to amplify the warming effect of CO2 i.e. increased water vapour in the atmosphere, what overrode it in the opposite direction during historical periods that CO2 decreased? Nothing. Positive feedback amplifies changes in both directions: Adding CO2 raises the temperature, which increases water vapour, which further increases temperature, etc. Removing CO2 reduces the temperature, which reduces water vapour, which further reduces temperature, etc. Edit: The Earth's climate is characterised by a number of feedback effects, both positive and negative, which operate on different time scales. The Wiki link gives a good summary of them. Link to comment Share on other sites More sharing options...
ntb Posted January 23, 2014 Share Posted January 23, 2014 Nothing. Positive feedback amplifies changes in both directions: Adding CO2 raises the temperature, which increases water vapour, which further increases temperature, etc. Removing CO2 reduces the temperature, which reduces water vapour, which further reduces temperature, etc. Edit: The Earth's climate is characterised by a number of feedback effects, both positive and negative, which operate on different time scales. The Wiki link gives a good summary of them. The Wiki isn't exactly clear on how the CO2 gets removed though. Something must otherwise we would have gone like Venus long ago. Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 The Wiki isn't exactly clear on how the CO2 gets removed though. Something must otherwise we would have gone like Venus long ago. That something is life! Living creatures extract carbon from the air and eventually bury it in the form of limestone, coal, oil, etc. It stays underground for many millions of years, until released back into the atmosphere by volcanic activity. This is called the geological carbon cycle. Recently, of course, life in the form of human beings has joined, and now far exceeds, volcanoes in putting carbon back into the atmosphere. Human emissions are about 150 times those of volcanoes. It's unlikely that this will be enough to turn Earth into another Venus, but it remains a distinct possibility. Link to comment Share on other sites More sharing options...
fluffy666 Posted January 23, 2014 Share Posted January 23, 2014 What changes? I really haven't noticed any at all. Indeed. The earth looks flat from where I'm standing. Link to comment Share on other sites More sharing options...
ccc Posted January 23, 2014 Share Posted January 23, 2014 What changes? I really haven't noticed any at all. What actual real world problems are proven results of global warming? I can't think of any. Increased flooding? Is there? More likely to be down to building on flood plains and changed land usage.. There is no point. Don't waste your time. You are trying to argue against literally a religion here. You may as well go on a catholic chat site and start questioning Jesus and God. Complete waste of time. I have just been out for a lovely run in the chilly Jock climate. Far better use of time. Link to comment Share on other sites More sharing options...
Mr Jib Fingers Posted January 23, 2014 Share Posted January 23, 2014 While the factors you mention almost certainly do play a part in increased flooding, heavier rainfall is also to blame. Average annual rainfall in the UK has increased by about 7% since the early 1900s, with 4 out of the 5 wettest years since 1910 (when records begin) occurring since 2000. I'm bothered by this explanation. We're constantly told that if things don't go to plan for the climate change models for a few years it is because it is down to weather not climate. But then conversely having a few wet years in a decade is somehow long enough to prove that the climate has changed. The period of time that you are permitted to say that observations show a change in climate rather than it just being down to the noise of weather seems to change if it supports the theory of man man climate change or not. If 10 years is long enough to detect long term trends then ok I'm on board for this. Let's hear the predictions of how the climate is going to change and then if the reality doesn't reasonably match the prediction then we'll know the whole thing was flawed. If 10 years isn't enough then let's not start saying things like a couple of wet years in one country proves anything at all. Link to comment Share on other sites More sharing options...
The Eagle Posted January 23, 2014 Share Posted January 23, 2014 There is no point. Don't waste your time. You are trying to argue against literally a religion here. You may as well go on a catholic chat site and start questioning Jesus and God. Complete waste of time. I have just been out for a lovely run in the chilly Jock climate. Far better use of time. Exactly, snowflux's posts are full of bold statements but short of actual proven facts as the whole CO2 'science' is based on estimates and assumption, not on hard proven and measured facts. 'Science' without facts is a pure belief system just like religions. Link to comment Share on other sites More sharing options...
corevalue Posted January 23, 2014 Share Posted January 23, 2014 No. That's a basic misunderstanding. Positive feedbacks amplify changes; negative feedbacks damp down changes. Wikipedia has some good entries on the topic: http://en.wikipedia....sitive_feedback http://en.wikipedia....change_feedback A very simpistic view of feedback systems. For a better description of the problems of analysing dynamic systems, this is the best description I have seen. It describes the derivation of the "error" (negative feedback) for a missile guidance system. The missile knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the missile from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is. Consequently, the position where it is, is now the position that it wasn't, and it follows that the position that it was, is now the position that it isn't. In the event that the position that it is in is not the position that it wasn't, the system has acquired a variation, the variation being the difference between where the missile is, and where it wasn't. If variation is considered to be a significant factor, it too may be corrected by the GEA. However, the missile must also know where it was. The missile guidance computer scenario works as follows: because a variation has modified some of the information the missile has obtained, it is not sure just where it is. However, it is sure where it isn't, within reason, and it knows where it was. It now subtracts where it should be from where it wasn't, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn't be, and where it was, it is able to obtain the deviation and its variation, which is called error. Ed. If you want a stable, predictable system, use positive feedback. Enough will make it lurch of to one extreme of the possible limits and stay there. If you want a wildly oscillating, or an unpredictable system chaotic system, use negative feedbacks. Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 I'm bothered by this explanation. We're constantly told that if things don't go to plan for the climate change models for a few years it is because it is down to weather not climate. But then conversely having a few wet years in a decade is somehow long enough to prove that the climate has changed. The period of time that you are permitted to say that observations show a change in climate rather than it just being down to the noise of weather seems to change if it supports the theory of man man climate change or not. If 10 years is long enough to detect long term trends then ok I'm on board for this. Let's hear the predictions of how the climate is going to change and then if the reality doesn't reasonably match the prediction then we'll know the whole thing was flawed. If 10 years isn't enough then let's not start saying things like a couple of wet years in one country proves anything at all. I'm not sure where you got the 10 years from, but you're right, that wouldn't be enough to detect a trend. The trend can be seen in the records stretching back to 1910. While increasing increasing rainfall in the UK is not a proof of MMGW, it is most likely attributable to it, given that we know that a warmer atmosphere can carry more water. Link to comment Share on other sites More sharing options...
The Eagle Posted January 23, 2014 Share Posted January 23, 2014 This interesting video is full of actual measured facts about CO2 unlike the mumbo jumbo from snowflux and his ilk: http://www.youtube.com/watch?v=YrI03ts--9I For those who don't have the time to watch it, basically the conclusion is that human activity does not in any measurable way influence CO2 concentration in the atmosphere. Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 A very simpistic view of feedback systems. For a better description of the problems of analysing dynamic systems, this is the best description I have seen. It describes the derivation of the "error" (negative feedback) for a missile guidance system. Reminds me of a colleague's thesis that I once tried to proof-read before giving up in bewilderment. Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 This interesting video is full of actual measured facts about CO2 unlike the mumbo jumbo from snowflux and his ilk: http://www.youtube.com/watch?v=YrI03ts--9I For those who don't have the time to watch it, basically the conclusion is that human activity does not in any measurable way influence CO2 concentration in the atmosphere. I assume that you've heard it through and fully understood it. Perhaps you could summarize his main arguments for reaching that conclusion. Link to comment Share on other sites More sharing options...
The Eagle Posted January 23, 2014 Share Posted January 23, 2014 I assume that you've heard it through and fully understood it. Perhaps you could summarize his main arguments for reaching that conclusion. My one line summary is in my previous post, if you would like to know more then watch it yourself, it's very educational (unlike your patronizing posts). Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 My one line summary is in my previous post, if you would like to know more then watch it yourself, it's very educational (unlike your patronizing posts). That's a summary of his conclusion, not his arguments. If you've understood the video, it should be no problem for you to summarize his argument in a few lines so I can decide whether it's worth an hour of my time. Edit: Also, I can support all of what I've said with references to data or scientific papers. Which points do you dispute? Link to comment Share on other sites More sharing options...
The Eagle Posted January 23, 2014 Share Posted January 23, 2014 That's a summary of his conclusion, not his arguments. If you've understood the video, it should be no problem for you to summarize his argument in a few lines so I can decide whether it's worth an hour of my time. It's my conclusion from watching the presentation, the presenter merely presents facts and the presentation is only half an hour, the remaining time is Q&A so if you really feel so strongly about this whole CO2 'business' then just watch it, you have wasted a lot more than half an hour posting hot air in this thread already,so saying you don't have time is a cheap excuse. Link to comment Share on other sites More sharing options...
Kurt Barlow Posted January 23, 2014 Share Posted January 23, 2014 This interesting video is full of actual measured facts about CO2 unlike the mumbo jumbo from snowflux and his ilk: http://www.youtube.com/watch?v=YrI03ts--9I For those who don't have the time to watch it, basically the conclusion is that human activity does not in any measurable way influence CO2 concentration in the atmosphere. Even though atmospheric levels have risen hand in hand with emissions since 1800. Please tell the alternative explanation - Martians, Fairies.... Link to comment Share on other sites More sharing options...
The Eagle Posted January 23, 2014 Share Posted January 23, 2014 Even though atmospheric levels have risen hand in hand with emissions since 1800. Correlation and causation are two completely different things. Please tell the alternative explanation - Martians, Fairies.... If you had watched the video then you wouldn't say this. Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 It's my conclusion from watching the presentation, the presenter merely presents facts and the presentation is only half an hour, the remaining time is Q&A so if you really feel so strongly about this whole CO2 'business' then just watch it, you have wasted a lot more than half an hour posting hot air in this thread already,so saying you don't have time is a cheap excuse. Look, we know both that there are any number of nonsensical YouTube videos out there, and life is short. For the last time, will you please summarize the main points for me so that I can decide if this is one of the few that are worth watching. Link to comment Share on other sites More sharing options...
The Eagle Posted January 23, 2014 Share Posted January 23, 2014 Look, we know both that there are any number of nonsensical YouTube videos out there, and life is short. For the last time, will you please summarize the main points for me so that I can decide if this is one of the few that are worth watching. You start sounding like a broken record... I'm at work (actually working, not simply pretending to work), I don't have the time to write a meaningful summary, this is certainly no nonsensical video it's a serious presentation, if you don't want to watch it because you fear it will shake your beliefs then don't watch it, I couldn't care less what you do. Link to comment Share on other sites More sharing options...
ntb Posted January 23, 2014 Share Posted January 23, 2014 That something is life! Living creatures extract carbon from the air and eventually bury it in the form of limestone, coal, oil, etc. It stays underground for many millions of years, until released back into the atmosphere by volcanic activity. This is called the geological carbon cycle. Recently, of course, life in the form of human beings has joined, and now far exceeds, volcanoes in putting carbon back into the atmosphere. Human emissions are about 150 times those of volcanoes. It's unlikely that this will be enough to turn Earth into another Venus, but it remains a distinct possibility. So plants are growing faster now than a few years ago in response to the increased CO2 levels and that is how historically high levels were reduced? Link to comment Share on other sites More sharing options...
Kurt Barlow Posted January 23, 2014 Share Posted January 23, 2014 Exactly, snowflux's posts are full of bold statements but short of actual proven facts as the whole CO2 'science' is based on estimates and assumption, not on hard proven and measured facts. 'Science' without facts is a pure belief system just like religions. Somewhat like your contrary views on vaccination Link to comment Share on other sites More sharing options...
snowflux Posted January 23, 2014 Share Posted January 23, 2014 So plants are growing faster now than a few years ago in response to the increased CO2 levels and that is how historically high levels were reduced? Historically high levels of CO2 were indeed eventually brought down by plant life and as carbonate in the shells of sea creatures. This takes a long time though, many thousands of years. Certainly, today's increasing CO2 levels will have a stimulating effect on plant growth (this is a negative feedback mechanism!), but this may well be cancelled out by the deleterious effects on their growth of environmental changes. In any case, it would be far too slow to compensate for the rate of fossil fuel burning. Link to comment Share on other sites More sharing options...
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