Climate Thought for the Day

Via Climate Skeptic:

The catastrophe that Al Gore and others prophesy as a result of greenhouse
gases is actually not, even by their admission, a direct result of greenhouse
gas emissions.  Even the IPCC believes that warming directly resulting from
manmade CO2 emissions is on the order of 1 degree C for a doubling of CO2 levels
in the atmosphere (and many think it to be less). 

The catastrophe comes, not from a mere 1 degree of warming, but from the
multiplication for this warming 3,4,5 times or more by hypothesized positive
feedback effects in the climate.   Greenhouse gas theory gives us warming
numbers we might not even be able to find amidst the natural variations of our
climate;  it is the theory of strong positive climate feedback that gives us the
apocalypse.

So, In a large sense, the proposition that we face environmental armageddon
due to CO2 rests not on greenhouse gas theory, which is pretty well understood,
but on the theory that our climate system is dominated by strong positive
feedbacks.  This theory of positive feedback is almost never discussed publicly,
in part because it is far shakier and less understood than greenhouse gas
theory.  In fact, it is very probable that we have the sign, much less the magnitude,
of major feedback effects wrong.  But if we are considering legislation to gut
our economies in order to avoid a hypothesized climate catastrophe, we should be
spending a lot more time putting scrutiny on this theory of positive feedback,
rather than just greenhouse gas theory.

  • Hank

    Positive feedback in the climate? Hello? Positive feedback means you're going to hit the rails. If any positive feedback existed in the climate, we would have hit the rails millions years ago, and stayed there. We simply wouldn't exist to ponder the question. By the very nature of positive feedback, rest assured that it doesn't exist in the climate. There is absolutely no reason to give credence to such a ludicrous notion. It's a notion generated by complete idiots who are lucky to get the correct shoe on the correct foot on any given day. Anybody who even contemplates that these idiots might have a point is guaranteed to have not the slightest iota of grounding in the hard sciences, and should report to the nearest soylent green processing center.

    Positive feedback is destructive. Negative feeback isn't. It's that simple.

  • Michael J. Bentley

    Feedback is something I can understand. I enjoy reading the many writings and comments on these blogs, and by spending much of my life as an engineer, can even understand a bit of the math. My occupation now is "sound engineering". And feedback is something that I have to deal with every day.

    Positive feedback is easily recognizable as a squeal (hum or whatever) that starts low in the background then rapidly increases to an ear shattering howl. In this case the console operator simply quickly reduces the offending channel (or the main volume) and returns it to a point just below it's previous level. This ends the positive feedback and allows the operator to research the cause of the feedback and eliminate it.

    Ringing is another example of positive feedback that is negatively damped so dies out itself. It tends to add unwanted high pitched tones to musical notes or speaker's words. This ring is annoying and is usually handled by a slight reduction in volume level and a tweek of some tone control (EQ for you sound buffs).

    Each of these has a characteristic pattern seen on a computer screen (or for those my age, an ocilloscope). Negative feedback is normally employed in amplifiers to eliminate feedback which is nothing more than an unwanted oscillation in the first place.

    The interesting thing in all the stuff I've been reading (from the sky is falling crowd too) is I see no indication of "ringing" or "feedback" in the "signal. It looks to me as a noisy source would.

    Humm, in my simplistic mind, it looks like the climate signal is in a really nice groove.

    I'd like to know from you science/math types if my simplistic viewpoint has merit or is just a bunch of ...wait for it... hot air.

    Keep up the good work!

  • Michael J. Bentley

    Feedback is something I can understand. I enjoy reading the many writings and comments on these blogs, and by spending much of my life as an engineer, can even understand a bit of the math. My occupation now is "sound engineering". And feedback is something that I have to deal with every day.

    Positive feedback is easily recognizable as a squeal (hum or whatever) that starts low in the background then rapidly increases to an ear shattering howl. In this case the console operator simply quickly reduces the offending channel (or the main volume) and returns it to a point just below it's previous level. This ends the positive feedback and allows the operator to research the cause of the feedback and eliminate it.

    Ringing is another example of positive feedback that is negatively damped so dies out itself. It tends to add unwanted high pitched tones to musical notes or speaker's words. This ring is annoying and is usually handled by a slight reduction in volume level and a tweek of some tone control (EQ for you sound buffs).

    Each of these has a characteristic pattern seen on a computer screen (or for those my age, an ocilloscope). Negative feedback is normally employed in amplifiers to eliminate feedback which is nothing more than an unwanted oscillation in the first place.

    The interesting thing in all the stuff I've been reading (from the sky is falling crowd too) is I see no indication of "ringing" or "feedback" in the "signal. It looks to me as a noisy source would.

    Humm, in my simplistic mind, it looks like the climate signal is in a really nice groove.

    I'd like to know from you science/math types if my simplistic viewpoint has merit or is just a bunch of ...wait for it... hot air.

    Keep up the good work!

  • Marcus

    I brought this up in another board recently. We're always hearing from the 'catastrophists' (is that a word? Should be) about the positive feedback loops and negative consequences but never about the negative feedback loops and positive consequences.

    If there are only positive feedback loops I imagine our planet would have turned into Venus long ago.

  • Michael J. Bentley

    First, sorry about the double post - reverberation in this venue is not a good thing...

    Yes, there is such a thing as negative feedback - where the outgoing signal is fed back to the incoming signal 180 degrees out of phase. Amplifiers use this to prevent going into oscillation. (OK I'm being general here...) and you're right, a positive feedback system that goes to oscillation (talking electrically here) will change at its resonate frequency (howl that is) which is determined by impedence or alternating current resistance. It will go to the maximum and remain there until something breaks.

    Humm, could it be that the ice-age - - -warm period oscillation is the resonate frequency of the earth??? (a dumb engineer thought...) And what would be the negative feedback - if any...

    Thanks for the support!

    It's snowing in Pueblo Colorado - no doubt the result of positive feedback...

  • Michael J. Bentley

    First, sorry about the double post - reverberation in this venue is not a good thing...

    Yes, there is such a thing as negative feedback - where the outgoing signal is fed back to the incoming signal 180 degrees out of phase. Amplifiers use this to prevent going into oscillation. (OK I'm being general here...) and you're right, a positive feedback system that goes to oscillation (talking electrically here) will change at its resonate frequency (howl that is) which is determined by impedence or alternating current resistance. It will go to the maximum and remain there until something breaks.

    Humm, could it be that the ice-age - - -warm period oscillation is the resonate frequency of the earth??? (a dumb engineer thought...) And what would be the negative feedback - if any...

    Thanks for the support!

    It's snowing in Pueblo Colorado - no doubt the result of positive feedback...