Unusual Climactic Stability

Newsbusters found this in a 1993 NY Times article:

The scientists said their data showed that significantly warmer periods and significantly colder periods had occurred during the last interval between glacial epochs, about 115,000 to 135,000 years ago. They said they could not tell whether that meant similar changes were in store. Their findings were reported today in two papers in the journal Nature. […]

The new studies found that the average global temperature can change as much as 18 degrees Fahrenheit in a couple of decades during interglacial periods, [Dr. J. W. C. White of the Institute of Arctic and Alpine Research of the University of Colorado] said. The current average global temperature is 59 degrees Fahrenheit. …

At one point between the last two glacial epochs, the climate melted enough polar ice to raise sea levels some 30 feet. As noted by a member of the drilling team, Dr. David A. Peel of the British Antarctic Survey, it was so warm in England that hippopotamuses wallowed in the Thames and lions roamed its banks….

In his commentary, Dr. White wrote: "We humans have built a remarkable socioeconomic system during perhaps the only time when it could be built, when climate was sufficiently stable to allow us to develop the agricultural infrastructure required to maintain an advanced society. We don’t know why we have been so blessed, but even without human intervention, the climate system is capable of stunning variability.

50 thoughts on “Unusual Climactic Stability”

  1. And to think that only 15 years ago a scientist like White could write clear, attractive English.

  2. And this is probably the most important part:

    We don’t know why we have been so blessed, but even without human intervention, the climate system is capable of stunning variability.

    Even if buffoons like this “Scientist” are absolutely 100% correct in their idiotic blather (they aren’t), there still is no way in hell to justify massive draconian measures that will crush world economic development.

    It is socialist peons like Scientist who are using this movement as a means of gaining power and economic rents, all in the name of “saving” civilization. There are far better ways to spend our finite resources.

    Completely, flatly bogus.

  3. I love the contortions denialists have to work themselves into. So scientists 15 years ago were honest and accurate, but in 15 years, our understanding of the climate system hasn’t moved on – oh no, scientists now are all frauds, intent on wrecking the global economy! Ha ha ha.

    “Mesa Econoguy” – you know fuck all about anything, you thick-headed ape.

  4. Y’know, I don’t think we thank Scientist enough. I mean, without him/her around, there’d be nobody to point to and say, “Yeah, that’s the opposition.” Makes even the meanest denier (as opposed to a skeptic, which is to say, denying without rational cause) looks positively brilliant by comparison.

  5. Res ipsa loquitur there, I’d say.

    Scientist, I know a hell of a lot more than you do about economics, you sausage-eating Bolshevik, and that’s at least half of this conversation.

    You can’t even get your “science” straight, so I’d keep my yap shut if I were you.

  6. And where the fuck is the economics in this post? Piss off to an economics discussion if you think you’re so great at it. You’re totally clueless about science. Fucking monkey.

  7. And where the fuck is the economics in this post?
    Posted by: Scientist

    Rorschach test. You failed.

    You (and morons like you) are attempting to argue, based on a statistical lie, and contradicted by the very same evidence quoted above, that you should run the economy based on your hunch.

    Having fairly extensive fancy-school science training (unlike you), I’m fairly confident you’re a) genuinely stupid, b) a moron, and c) probably mildly (?) retarded. And that very same training allows me to expand my perception to encompass a larger view, which you are totally incapable of (see letter c above).

    Meanwhile, you’re drooling on the windscreen, and we’re debating the actual issues, like how fucked up your models are.

    Al Gore invented the internet for fools like you, I would suggest using it for actual research. (Actually, Tim Berners-Lee “invented” the first browser for CERN, utilizing a previously established DARPA infrastructure, but you’ll have to let AlGore know that.)

    Since it’s more or less a “free” medium, you must be cautious about your information. That involves being able to discern between intelligent, and unintelligent sources.

    Guess which one you are, you talentless ass-clown?

    What a fucking retarded idiot…..

  8. Aaaand there’s the reality check. Sigh. Mesa, not to be your mother, but it does do our side a wonder of good when it’s the other side engaging in name-calling, a habit which Scientist is so obliging about.

  9. Sorry Adirian, apparently, all’s fair in love & “science” now….

    Plus, since this asshole wants to confiscate $45 trillion, I think it’s more than fair to namecall, insult, punch, whack, and otherwise abuse people like this.

    Get the science right, knock off the moral indignation bullshit, and I’ll listen.

    Until that happens, expect retaliation.

  10. Well you have to admit that “scientist” has not rebutted the article at all.

    Of course he does not realize it damages the AGW mantra that this “current” warming trend (not anymore) in THIS interglacial epoch is UNPRECEDENTED.

    When the article shows that the previous Interglacial period had much more dramatic warming trends.

    LOL

  11. Okay, okay, okay, last “Scientist is a moron” post:

    And where the fuck is the economics in this post?
    Posted by: Scientist

    “We humans have built a remarkable socioeconomic system during perhaps the only time when it could be built,…

    Seriously, dude. You’re a fucking roadkill gourmet moron, extraordinaire. I salute you. That takes major effort. Well played, sir!

  12. Ha ha ha. The single use of the word ‘socioeconomic’ does not make this a post about economics. And please do point out to me a single post I’ve made anywhere here about economics, that would give you cause to say this asshole wants to confiscate $45 trillion. Fucking retarded cunt.

  13. And please do point out to me a single post I’ve made anywhere here about economics, that would give you cause to say this asshole wants to confiscate $45 trillion.
    Posted by: Scientist

    No, burning fossil fuels is not a prerequisite for being wealthy, and cutting CO2 emissions will not limit economic growth or increase poverty.
    Posted by: Scientist | May 08, 2008 at 04:48 PM

    The second half of this statement is false. The first half is conjecture.

    Have a nice day.

  14. Can you understand a simple question? Please do point out to me a single post I’ve made anywhere here about economics, that would give you cause to say this asshole wants to confiscate $45 trillion. What kind of fucking idiot just invents other people’s views?

  15. Scientist, as a new commenter who is interested in. Both sides of these issues and trying to hear out the differing views impartially, I just can’t resist writing to ask you to at least make an effort not to be such a complete jerk all the time. You can make points without constantly calling everyone names and being arrogant. Really. I see some others do this but no one nearly to tjhe extent you always do. These guys might like your obnoxious behavior because it reflects poorly on your “side,” but I honestly wish you would just go away since you plainly won’t clean up your act.

    Warmest regards (pun intended),

    CThomas

  16. CThomas – I am only abusive to those who are abusive to me. I see no reason to be polite when there are people being fantastically rude to me. I’ll continue to be polite to people who are polite to me, and very rude to people who are rude to me.

  17. Scientist screams:

    “Fucking retarded cunt.”

    So you are SEXIST along with your other wonderful qualities??

    Seriously, CHILDREN should be SEEN and not HEARD!!

  18. Scientist drooled:

    “So scientists 15 years ago were honest and accurate, but in 15 years, our understanding of the climate system hasn’t moved on – oh no, scientists now are all frauds, intent on wrecking the global economy! Ha ha ha”

    Yup, except for the 31,000 and counting who disagree with the CONSENSUS!!

    By the way, if you are a warmer your physics hasn’t moved on from a guy in the early 1900’s who was refuted!!

    HAHAHAHAHAHAHA

  19. CThomas,

    Quite so. I’ve suggested that to him on any number of previous occasions, but we eventually came to the conclusion that his aim is not to have a debate or to make a positive contribution, but simply to cause annoyance and trouble.

    He will disagree with anything said, often in as patronising a way as he can. And then if anyone tries to debate the point he dodges and weaves with fallacious or dishonest tactics until you give up. And if you throw any of his own arrogance back at him, he starts up with the foul-mouthed insults. When I’ve seen this sort of psychological problem before, it’s usually from those with extremely low self-esteem using it to build their self-image up. Trying to confirm to themselves the belief that they’re better than the average by picking fights with those they consider to be weaker, and then counting their ‘victories’ over and over. Basically, the inadequate playground bully mentality.

    An intelligent pro-AGW contributor would be welcome, if they were polite about it. But there are certain rhetorical advantages to having a troll instead, in that it thoroughly discredits the pro-AGW position in the eyes of bystanders at an emotional level. Since he won’t go away, winding him up and setting him going provides excellent ‘target practice’. It’s not terribly constructive, but after having tried to advise him for his own good and got nowhere, we had might as well have some fun.

    If you want a sensible debate for the purposes of listening to both sides impartially, I suggest the only way is for you start one yourself. We can probably ignore the troll if there’s something better going on. But on the whole, you would probably get a better idea of the AGW-sceptic position from one of the more technical sites – ClimateAudit, CO2Science, ScienceBits, Roger Pielke’s Prometheus, Watts Up With That and SurfaceStations. Or look out for interviews with people like Richard Lindzen, William Gray, John Christy, or Roy Spencer.

  20. Stevo — thanks for the sensible response, and for the references to those other sites. I’ll be sure to check them out.

    Best reagrds,

    CThomas (finally writing from a real computer)

  21. Stevo – using the royal ‘we’ again? It does make you look a bit crazy. Now, have you ever complained to any of the people who are regular viciously rude to me? No? Why not?

    Yet again you show what a tribal view of this you have. You really think there are two sides? And that both deserve equal exposure? You recommend the writings of Anthony Watts, who does not understand that GISS, HadCRUT, RSS and UAH anomalies are not all measured relative to the same baseline? You recommend the writings of Roy Spencer, an avowed creationist? And Richard Lindzen, who works as a consultant for oil and gas companies, and claims that lung cancer is not linked to smoking?

    It really is painfully obvious that you have a rigid, preconceived view of this subject, and you will happily ignore anything that doesn’t support it, and enthusiastically endorse anything that you think does support it.

  22. Why would I complain when I see you bring it on yourself? You’re rude and arrogant to everyone else, they’re rude back, so you start swearing.

    I’ve told you time and time again that if you want people to listen to you, to respect what you say, you have to listen to and respect them in turn. To acknowledge it when they’re right. To stick to the argument instead of inserting snide asides and insults. To be tolerant and understanding of those who don’t know or haven’t heard of something. To thank people if they tell you something you didn’t know, instead of trying to pretend you did, or dodge the issue. To be patient when people want more detail, or have arguments or objections. To accept that intelligent people can disagree about things. To take both wins and losses gracefully. It’s your attitude that makes people want to hit you, to fight with whatever you say. If you don’t respect them, why would they respect you?

    Intruding in a place where your view is in the minority, in opposition to what most people there currently believe, means you start off with a handicap which you have to work to overcome. You are always going to get a certain amount of crap, and meet obdurate people who won’t change their opinions. But if you’re polite and civilised and patient, and if you maintain the highest standards of debate – be logical, present evidence, be willing to go into the argument in detail – then people may start to respect you even though they don’t disagree with you, and then later some of them may come to change their views on some parts if they think you’re right.

    If you start off with the attitude that everyone else is a moron and should be told so, and then start throwing around ad hominem arguments and appeals to authority, they’re a) not going to listen, b) will think you’re a jerk, c) will dismiss everyone who holds the same opinions as you as a jerk, and d) will eventually tell you so. And I’m not in the least bit surprised that they do.

    And calling me “crazy” is hardly the way to get me on your side! Or to help you out fighting your corner.

    You get repeatedly insulted because you’ve done everything you can to deserve it. I can’t help you. Only you can.

  23. Think I want you on my side, you patronising shit? You tell it entirely the wrong way around. I wonder why. I have never been rude to someone who wasn’t rude to me first. I am only ever rude when other people are rude to me. I’ll thank someone for telling me something I didn’t know, if and when that happens.

    be logical, present evidence, be willing to go into the argument in detail – yep, that’s what I do. What you do is refuse to accept any evidence that goes against your preconceived ideas. That’s what everyone here does. When I point out the egregious misuse of data, the outright lies, the misunderstandings and the unscientific arguments that the author of this blog trots out time and time again, other people are rude to me. And I’m fucking rude back. Deal with it.

  24. You’ve been rude to people who just disagreed with you, and said you was wrong. You don’t just point out what you think are misunderstandings, you add nasty little comments about how they have to be idiots to have misunderstood. You might think them justified, but nobody else does, they just see it as arrogant nastiness.

    Tell me, on what occasion have you ever accepted any evidence that goes against your preconceived ideas? What would it take to convince you that the ‘consensus’ IPCC ipse dixit could be wrong? Because if your ideas are not falsifiable, they’re not science. I have, from time to time, acknowledged points you’ve made. At first out of principle, and later just to see what you’d do. On the stability of positive feedback question that you’ve often argued about, I’ve even provided explanations and technical arguments to support it (and without having to be rude to anyone while I did so). I can do it. I can’t think of a single occasion when you have, though.

    You are not willing to go into arguments in detail, you post a link to a “peer-reviewed” paper and think that should be the end of the matter – that no further discussion is necessary or possible. (Blatant Appeal to Authority – which you have never understood to be a fallacy.) Unless we post such a link, in which case you’ll allude to subsequent work, attack the author’s credibility, or complain that we only link to results that support our case (as if you didn’t). You recently challenged (rudely) a claim that the latest IPCC report didn’t offer a reason for the Arctic warming orders of magnitude faster than the Antarctic, but when asked on what page of the report they did so, you were quite obviously unable to answer. You could have simply said that you didn’t know for sure that it did, but that you understood that the latest thinking was that the whole of the observed Arctic warming couldn’t be directly attributed to greenhouse effects, that part of the warming of the Arctic was due to other natural effects like the Northern Annular Mode and North Atlantic oscillation affecting the winds and currents, and if necessary be prepared to explain what they were, how they worked, and why (if it wasn’t obvious) they didn’t apply to the Antarctic. Technical details. Physics. Evidence. Not stupid links to the report and an invitation to read it myself. The minor concession combined with relevant technical input would have bought you considerable credibility. But instead you danced around, trying to get me to help you out without ever admitting that you had no idea what the IPCC report said on the subject, and that you’d just been caught out shooting blanks. That sort of behaviour earns you no respect.

    I don’t need to deal with it, because it’s not bothering me. You’re the one who gets all the hostility as a result of your antisocial behaviour.

    You’re not welcome, you’re not useful, you’re not deserving of any respect.

    You won’t get any from me. As you say, “Deal with it”.

  25. What a stupid discussion. Nobody even mentions the complete lunacy of the blogger on posting this “the climate is chaotic” as in being in complete contradiction with his “the climate is a negative feedback system!!” cry. It’s so flagrant! Which is it?

    Of course, it doesn’t matter. If yesterday, negative feedback was the way to disprove GW, then we’ll use it, if today a new find finds that the climate is completely chaotic and can change dramatically in two decades, then THAT’S the way to disprove GW.

    Care not about coherence! What’s the point of THAT?

    So stop discussing an idiotic and childish discussion of bad language. Stick to the points in question. The blogger has made a profound mistake and blunder. As you seem to like to say

    DEAL WITH IT

  26. Stevo, well said. Luis Dias, if you think these are side issues, I respectfully believe you are mistaken. These are the fundamental prerequisites to meaningful interaction that is designed to lead to mutual understanding. Of course, you can take the view that meaningful interaction is simply unimportant because anyone who holds (or even is interested in hearing) the opposing view is “the enemy,” and ipso facto dishonest or stupid (or both). But then that disqualifies you from demanding or expecting others to hear your views on the merits any more than you hear theirs. (Throughout, I’m using the generic “you” here — not directed to you in particular.) And sadly, for whatever reason, these sorts of problems seem alarmingly prevalent on this issue, perhaps because of the serious practical consequences of these issues.

    Regards,

    CThomas

  27. If you don’t like other people’s manners, rightfully say so. But to troll around continuous threads rambling about who’s the most idiot person in the forum tells me a lot about the level of idiocy that has been reached, by all the contenders.

    Grow up. Have you nothing better to do than calling other people’s names just because you must defend your flags?

    And yes, its serious. That’s why good manners are essential. But to stop annoying third parties with personal flame-wars is also a part of a good manner.

  28. Look, my friend, nobody’s going around trolling the message boards for manners infractions. But at a certain point this sort of thing does get genuinely distracting. If you don’t think that floor of minimal civility has been reached here, or if you are able to focus on the merits in a discussion even when they are buried in invective and obscenities, then more power to you. But I doubt I’m alone in my contrary views on these points, and I respect Stevo’s points about them.

    Regards,

    CThomas

  29. “You’ve been rude to people who just disagreed with you, and said you was wrong. You don’t just point out what you think are misunderstandings, you add nasty little comments about how they have to be idiots to have misunderstood. You might think them justified, but nobody else does, they just see it as arrogant nastiness.”

    Keep in mind that “Scientist” is just a troll. In other words, his goal is not to convince anyone about CAGW — his only goal is to evoke a reaction from people. i.e. to yank their chains. He doesn’t care one way or another about global warming.

  30. If you think he’s a troll, then the internet rule is simple: don’t feed it.

    Unless you want a flame-war going on.

  31. Ah Stevo, what a strange character you are. So you claim that you knew all along that there is a rather good understanding of why the Arctic is the fastest warming part of the globe, but rather than pointing out to the author of the blog that he’d (yet again) been barking up the wrong tree, you thought you’d rather try to insinuate that I didn’t know what the IPCC said about it? Can you really not bring yourself to admit that a fellow denier might be thoroughly mistaken? And do you really think a paper from 1999 represents ‘the latest thinking’?

    I don’t think you understand what falsifiable means. If I generally ignore yapping idiots who don’t understand science, that does not mean my ideas are not falsifiable. Real world observations are what matter, not the ramblings of small-minded right wingers.

    I have nothing to deal with. I couldn’t give a shit if a bunch of 12 year olds are rude to me. I’m rude back, and I explain the science at the same time. If it’s not bothering you, then how about you shut the fuck up?

    And who are you, exactly, to tell me I’m not welcome at a website which isn’t yours? Fucking self-important wanker.

    Now then, I can point out your idiocies all day, and you can say “Oooh, but you’re making your side look bad!”, and I can not give a shit. Or how about this. As you often seem to think you’ve been appointed spokesperson for all the deniers here, how about you ask them all to not be rude or childish in their responses but to stick purely to science. And how about you point out their mistakes, like poor sunsettommy failing to understand what ‘peak recorded anomaly’ means. And how about you admit your own mistakes, like your false claim that recalculating the four main temperature datasets so they referred to the same reference period by the simple method I explained to you did not give this graph?

  32. “If you think he’s a troll, then the internet rule is simple: don’t feed it.”

    That’s correct. Normally I don’t pay any attention to Scientrollogist’s posts.

  33. Scientist,

    What’s your goal here?

    If it’s to point out errors in this blog, have them acknowledged and, perhaps, persuade a few non-believers, then you’d do well to follow SteveO’s advice.

    If it’s just to make yourself feel more important at a cost of turning some lurkers off of AGW, then ignore him.

    Whether or not you’re doing the right thing depends on what you’re trying to accomplish.

    P.S. I don’t like the “don’t feed the troll” mantra. Too often trolls are identified as being anyone with the opposite opinion.

    And, Mesa, “our side” looks better when “their side” is the only one behaving badly.

  34. BillBodell – I comment here to point out grievous errors in scientific understanding. There are many. No-one appreciates being told they are wrong, so people are rude to me. I am quite happy to be very rude back. I only ever respond in kind. I only reflect back what is thrown at me. If someone doesn’t like what they see in the mirror, it’s not the mirror’s fault, is it?

  35. Scientist must routinely argue with mirrors over who is being reflected by whom.

    And Luis, you misunderstand what a skeptic is, if you think it is contradictory to posit multiple approaches which contradict one another – a skeptic is somebody who believes the evidence is not sufficient to make a claim; if there are two equally valid propositions, it would be intellectually dishonest to mention only one (although a good “popular” skeptic should make clear what he or she is doing). I could go into more detail, but let’s address your claim that the approaches in question ARE contradictory, first, because I also disagree there –

    First, the claim is not that climate is chaotic, in the purest sense of that word – it is that climate has large internal variances, possibly, but not decidedly, as a result of external variable inputs. (Solar input is one such example, as is orbital variances.) A ball at the bottom of a bowl is the general example of a system in a state of negative feedback. A magnetic force acting on that ball might pull it to one side – this would be an external variable. In this example, changing the magnetic force results in a change to the ball’s x (where x is the dimension connecting the center of the ball to the “center” of the magnetic force, i/e, the angular vector) coordinate – and likely in some subsequent and quite substantial wobbling. The ball is still dominated by a negative feedback, but it can still experience fairly large internal variation before the energy balance returns to normal.

    Climate is somewhat more complex, but needless to say it is possible for it to be dominated by negative feedbacks, and still experience considerable internal variability – indeed, the size of the variability gives a very good clue as to the scope of the feedbacks holding climate in check. By scope I mean the size of the bowl – as a negative feedback can be very powerful, or have a very wide range of effect. Generally feedback effects follow the same trend as atomic forces – the more powerful, the more quickly the force dissipates over distance (That is, the steeper the bowl, the smaller the circumference/radius), and the less powerful, the less quickly (That is, the reverse – the gentler the slope, the larger the circumference/radius.) The reason for this has to do with energy balances and entropy, and I shan’t get into it, but know that as a rule of thumb it generally holds.

  36. I misunderstand what a skeptic is? Oh, I’m sorry if I’m skeptical of any skeptical incoherence of thought. I thought that was only fair game in a skeptic’s blog. Or are we just throwing enough garbage cans to the “mainstream” cloud of scientists to give them literal headaches? If you try make a point about how the climate is ruled by negative feedback, and how wrong all of the mainstream science really is about that, how stupid and completely idiotic it is to post a subsequent vision on how the climate on earth is, after all said and done, “chaotic”? If you can’t see the complete lunacy of this, I’m sorry.

    The ball is still dominated by a negative feedback, but it can still experience fairly large internal variation before the energy balance returns to normal.

    I don’t agree with much you said, but if it “can still experience fairly large internal variation”, then a surge of, oh I don’t know, like 7 degrees celcius is not exactly off the table, now is it?

    Generally feedback effects follow the same trend as atomic forces

    Is that an equation or smth?

    You’ve said idiocies before, and you retracted in your last comment, acknowledging that “it can still experience fairly large internal variation before the energy balance returns to normal.” so I don’t exactly believe in your words. I’m sorry for being skeptical. Show me evidence for this and I’ll think better about it.

    A skeptic, in my dictionary, is someone who doesn’t think that continuous ad hominems and offensive behavior are a good argument. Snobbist smugness should always be met with a) ignore it b) refute the points without any personal remarks (as if the contender doesn’t exist) c) stick to the argument.

    I know, I don’t always follow this rule of thumb, I have little patience, but when things go out of hand, it seems good to get back to it.

  37. Billbodell

    “P.S. I don’t like the “don’t feed the troll” mantra. Too often trolls are identified as being anyone with the opposite opinion.”

    I’d rather people follow that rule than posting nasty stupid ad hominems and offensive remarks just because they are pissed off at their target.

    I don’t take scientist as a troll, but if I saw myself resort to call him an idiot innumerous times, then I’d have labelled him as one in my head already. Thus the rule. It’s a pain to watch this kind of idiotic ping pong over and over again, when a good discussion could be maintained instead. And please don’t go over that “it’s their fault, not mine”, again, scientist. You and your “opponents” lost your grip.

  38. “Too often trolls are identified as being anyone with the opposite opinion.”

    I agree, but in this case I am pretty confident that “Scientist” is a troll.

  39. It seems to me (correct me if I’m wrong) that there is an inherent problem with positive feedback in the climate system.

    Let’s first look at the two different types of feedback: internal and external. External is where some external forcing alters the effect of the initial cause for a change. That is in positive feedback, increase in “x” causes an increase in both “y” and “z” and an increase in “y” causes an increase in “z”. This means that in positive external feedback, when “x” changes, the direct change that causes in “z” is amplified by the change in “y”. An example of this would be the posited cosmic ray hypothesis. Negative external feedback works similarly, only decreasing or even reversing the initial change.

    Internal feedback is a whole different kettle of fish. In negative feedback, an increase in “x” causes an increase in “y”, which causes a DEcrease in “z”. That amplifies (if that’s the word) the increase by between 0 and 1 – we’ll say 0.5 for the time being. So increase “1” in “y” caused by “x” means “z” falls by “0.5”. This lowers “y”‘s increase to “0.5”, but this increases “z” to “-0.25”, raising “y” to “0.75”, decreasing “z” and so one. The point is, the system settles at a value (2/3 in this case). Internal positive feedback does not.

    In internal positive feedback, when “x” therefore “y” rises, so does “z”, increasing “y” again, which again raises “z” etc. “y” carries on rising out of control. Our climate system simply cannot have NET positive feedback or any change up or down, however slight would result in runaway warming or cooling until equilibrium is reached; clearly, once all the ice caps have melted and humidity is at 100%, there is very little positive feedback can do. But the point is, our Earth has not in recent geological history (or, I assume, ever) experienced runaway warming or cooling to this point of equilibrium or else we would not see ice ages that revert back once it has reached it’s peak/trough. We have obviously not reached the point after which positive feedback can have no more effect, or we would not be discussing this.

    Therefore, our climate MUST have no net feedback or negative feedback or we would currently be in a steaming hothouse or a ball of ice. Whatever positive feedbacks may exist, there HAS to exist negative feedback of equal or greater magnitude, or we would have gone the same way as Venus and already have experienced runaway warming/cooling. The only example of internal positive feedback is nuclear fission. Yeah…

  40. It seems to me (correct me if I’m wrong) that there is an inherent problem with positive feedback in the climate system.

    Let’s first look at the two different types of feedback: internal and external. External is where some external forcing alters the effect of the initial cause for a change. That is in positive feedback, increase in “x” causes an increase in both “y” and “z” and an increase in “y” causes an increase in “z”. This means that in positive external feedback, when “x” changes, the direct change that causes in “z” is amplified by the change in “y”. An example of this would be the posited cosmic ray hypothesis. Negative external feedback works similarly, only decreasing or even reversing the initial change.

    Internal feedback is a whole different kettle of fish. In negative feedback, an increase in “x” causes an increase in “y”, which causes a DEcrease in “z”. That amplifies (if that’s the word) the increase by between 0 and 1 – we’ll say 0.5 for the time being. So increase “1” in “y” caused by “x” means “z” falls by “0.5”. This lowers “y”‘s increase to “0.5”, but this increases “z” to “-0.25”, raising “y” to “0.75”, decreasing “z” and so one. The point is, the system settles at a value (2/3 in this case). Internal positive feedback does not.

    In internal positive feedback, when “x” therefore “y” rises, so does “z”, increasing “y” again, which again raises “z” etc. “y” carries on rising out of control. Our climate system simply cannot have NET positive feedback or any change up or down, however slight would result in runaway warming or cooling until equilibrium is reached; clearly, once all the ice caps have melted and humidity is at 100%, there is very little positive feedback can do. But the point is, our Earth has not in recent geological history (or, I assume, ever) experienced runaway warming or cooling to this point of equilibrium or else we would not see ice ages that revert back once it has reached it’s peak/trough. We have obviously not reached the point after which positive feedback can have no more effect, or we would not be discussing this.

    Therefore, our climate MUST have no net feedback or negative feedback or we would currently be in a steaming hothouse or a ball of ice. Whatever positive feedbacks may exist, there HAS to exist negative feedback of equal or greater magnitude, or we would have gone the same way as Venus and already have experienced runaway warming/cooling. The only example of internal positive feedback is nuclear fission. Yeah…

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