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Post by icefisher on Jun 30, 2010 23:40:10 GMT
Gee I don't see any clouds on that chart! Was everything just sort of a plug figure divvying up the needed perturbation represented by clouds because nobody has clue one what it was? Must be dang hard to capture clouds in an icecore bubble. LOL ;D A nice role for clouds would be negative feedback. As an orbital move is made away from the sun CO2 becomes more important as a greenhouse gas moderating cooling (like we see in the Arctic perhaps misapplied as an amplification) As the orbit adjusts towards the sun water increases its role making CO2 less important. Seems logical as opposed to the theory that water only changes states in the presence of CO2 changes.
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Post by northsphinx on Jul 1, 2010 6:19:50 GMT
Socold you wrote: "The glacial/interglacial cycles are timed with orbital cycles. Clearly they are externally forced. If the climate reacts to those forcings by changing cloud forming and allowing in more or less sunlight, that would be a feedback."
But that is a dramatic difference in a orbital cycle that change high latitude season incoming radiation with a factor of 50-100 w/m2 than a earth average claimed forced radiation change of 2-3w/m2 induced by CO2. This averaging of radiation is plain wrong. And it fails completely when explaining a orbital cycle. Ice ages are there because of change in absolute incoming radiation. Not average.
An orbital cycle explanation of glacial times also suggest that the needed forcing to make a change is in that range. Locally= high latitudes about 25-30 times larger than any claimed CO2 influence. THEN is the changed albedo cooling the earth. And there is a new equilibrium climate state regime. That new equilibrium climate state need a low radiative sensitivity to not fall out from this new orbital induced state at once.
So to start or stop an ice age do the earth need a absolute radiation change of 50-100 w/m2 in high latitudes. According to Your orbital view.
That should tell You that CO2 forcing cant be the reason for ice ages. Or for melting the poles ice sheet.
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Post by steve on Jul 1, 2010 7:01:23 GMT
steve, They did not just keep rising or we would not be here. Water vapor does not merely act as a ghg. Clouds change everything and they are notably a big problem for CAGW promoters. True believers like yourself are the only one ignoring things here, and it is rather pitiful. I was assuming people were bright enough to not fall into the trap of claiming feedbacks go on forever. The clue was right above you when you were writing the above.
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Post by steve on Jul 1, 2010 7:03:27 GMT
That's a god of the gaps argument. Not really...since your side claims it knows all of the forcings and feedbacks but can't explain the LIA/MWP. I am merely pointing out the gaps in your "gods". Since they claim the knowledge but cannot explain the LIA/MWP there must indeed be a pretty substantial "gap" in there. There are very reasonable explanations for the LIA and MWP. Didn't you know that.
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Post by steve on Jul 1, 2010 7:12:06 GMT
No. For example, looking at just a water vapor feedback: The energy comes from the sun. The extra CO2 results in less energy radiating from the earth. The energy build up in the earth warms the earth. The warming causes a rise in humidity. The extra water vapor acts as a greenhouse gas and *even less* energy radiates from the earth. This causes a bit more warming. Runaway is usually prevented because radiation is proportional to temperature to the power 4, so a few degrees is enough to balance the reduction in radiation caused by the CO2 and the water vapor. The last four steps are relevant whether the initial cause of warming is a build up of CO2, an increase in TSI, a change in albedo etc. etc. None of it breaks any of the laws of thermodynamics. Not the first. Not the second and not the zeroth. Your original statement. "Warm the climate a bit and it will tend to warm a bit more. Cool it, and it will tend to cool a bit more." That is not right. You know that, so now You changed to vapor feedback. As I suspect You would do. Then You claim that a strong vapor feedback is no problem because of radiation is proportional to temperature to the power 4. That is the Planck effect which behaves like a strong negative feedback. That prove a negative feedback from vapor increased temperature, if You think twice about of what you write. The two posts are consistent. The second post looks, in particular, at the water vapour feedback. It could have made similar points by looking at the albedo feedback from melting ice, but it is fair to say that the albedo feedback from melting ice was more important in the ice age cycles than now. It could have looked at clouds, but it is fair to say that clouds may act as a negative forcing despite what most models say. I know that the proportionality of radiation to the power 4 is called the Planck feedback. Why does giving it a name change its character Why does proving that some feedbacks are negative feedbacks change the observed fact that most feedbacks tend to be positive feedbacks Why is it relevant to make this point when the point I am making is that past climate variability cannot be explained unless you have positive feedbacks. Since we had positive feedbacks in the past (even after making estimates for feedback from changes in albedo and so forth), it is not unreasonable to look for positive feedbacks now, unless you are prepared, like poitsplace, to say that "God commanded that positive feedbacks due to CO2 would be zero".
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Post by northsphinx on Jul 1, 2010 9:48:08 GMT
Steve You ask two specific questions "Why does proving that some feedbacks are negative feedbacks change the observed fact that most feedbacks tend to be positive feedbacks " Why is it relevant to make this point when the point I am making is that past climate variability cannot be explained unless you have positive feedbacks." Because: It is assumed that there is radiative positive feedbacks because current radiant models need positive feedback to explain climate variability. There is no real observation of positive feedback other than model calculations. My point is that temperature feedback is negative. CO2 feedback is also negative if the atmosphere is cooled by radiation and heated by convection. Then is vapor and cloud left in the calculation. Which depending on many thing can be acting as positive or negative feedback. My answer is that the radiative model start from wrong initial assumptions.
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Post by hunter on Jul 1, 2010 11:33:55 GMT
steve, I am bright enough to know not to fall for apocalyptic bullshit. I am bright enough to know that CO2 is not the main driver of climate and will not drive world climate to a catastrophe if it has not done so in the past when it was higher. Arguing from your gullibility and ignorance does not make you bright. And in our part of the country, where the humidity is now >75% for several days due to Alex, the net impact has been to drop temps significantly. That is because humidity has this habit of forming clouds. As I have said before, and you perfectly illustrate, AGW/CAGW is a social mania, not a science.
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Post by steve on Jul 1, 2010 13:35:43 GMT
steve, I am bright enough to know not to fall for apocalyptic bullshit. So am I. In that sentence I spotted a strawman argument, and a logical fallacy wrapped up with the (likely) error of fact. Are you bright enough to know why I think that? Well in most aspects of my life I am not gullible - eg. I've never invested in the stock market , and while I'm ignorant, my stand concurs with that of many people who are patently bright. Suggest you look up the concept of relative humidity to spot where you've gone wrong here. I seem to have run out of fish to shoot in this barrel. You are definitely the one with the maniacal fixation on those who you perceive as alarmist.
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Post by steve on Jul 1, 2010 13:46:56 GMT
Steve You ask two specific questions "Why does proving that some feedbacks are negative feedbacks change the observed fact that most feedbacks tend to be positive feedbacks " Why is it relevant to make this point when the point I am making is that past climate variability cannot be explained unless you have positive feedbacks." Because: It is assumed that there is radiative positive feedbacks because current radiant models need positive feedback to explain climate variability. No. Radiative positive feedbacks are a product of the model because the physical laws as simulated in the models tends to result in the models keeping relative humidity constant. Therefore as temperatures rise, absolute humidity rises. Observations are consistent with predictions of constant relative humidity (but because we are only talking of a small percentage change in absolute humidity and a lot of weather variability the error bars are quite large). Observations of past climate change are hard to explain without invoking additional feedbacks. I recall we've already discussed your faulty understanding of radiative cooling in another thread. Vapor definitely positive. Cloud possibly positive, possibly negative...
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Post by northsphinx on Jul 1, 2010 14:43:39 GMT
No Steve "No. Radiative positive feedbacks are a product of the model because the physical laws as simulated in the models tends to result in the models keeping relative humidity constant. Therefore as temperatures rise, absolute humidity rises." Relative humidity constant if temperature rise? That is a very good example of wrong assumptions in the radiative model. Then "Observations of past climate change are hard to explain without invoking additional feedbacks." But it is easy without positive feedback if You leave the "average forcing corner" and see to local conditions . As orbital changes in high latitudes. Local change do change global circulation pattern. That change local and global climate and that change the radiative balance. In that order! A good example is ENSO. Or do You belive CO2 balance start a El nino? But of course is then CO2 not the cause and that must be difficult to comprehend. And: "Vapor definitely positive. Cloud possibly positive, possibly negative..." and cloud is formed by what? Forgot that? If vapor enter the atmosphere and are wind driven polewards and form cloud in high latitudes is that a very strong positive forcing. Especially locally in high latitudes. If vapor is lifted locally to condensation levels to form clouds is that a negative forcing. As in the tropics. A global circulation pattern that drive moist air polewards for cloud forming is a positive forcing. A global circulation pattern that keep moist air in low latitudes is negative forcing. That is the global circulation is the strongest forcing! Not temperature, not CO2, not CH4. Even not vapor itself. Add Svensmark hypothesis to this and You can model climate shifts depending on CR. Because of changed circulation pattern.
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Post by icefisher on Jul 1, 2010 15:35:43 GMT
Not really...since your side claims it knows all of the forcings and feedbacks but can't explain the LIA/MWP. I am merely pointing out the gaps in your "gods". Since they claim the knowledge but cannot explain the LIA/MWP there must indeed be a pretty substantial "gap" in there. There are very reasonable explanations for the LIA and MWP. Didn't you know that. Send your explanation to Keith Briffa and Michael Mann. They haven't seen the memo yet.
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Post by icefisher on Jul 1, 2010 15:46:59 GMT
Vapor definitely positive. Cloud possibly positive, possibly negative...
I sure am glad that the clerks at my local grocery store don't count change like that. Lets see copper, copper, nickle. . . . .uh, paper is not a precious metal so we will leave that out. ;D ;D
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Post by hunter on Jul 1, 2010 16:01:25 GMT
I would say that never investing in the stock market demonstrates economic and historical illiteracy and reactionary ignorance rather well. The gap in your reasoning irt MWP LIA and RWP is that it is the CAGW promoters who ahve disappeared these historical facts due to their inconvenience. The irony of your offering a badly informed god of the gaps argument is pleasant to watch.
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Post by northsphinx on Jul 1, 2010 21:26:09 GMT
"AFRICAN ENVIRONMENTAL AND CLIMATIC CHANGES AND THE. GENERAL ATMOSPHERIC CIRCULATION IN LATE PLEISTOCENE. AND HOLOCENE" 128.186.98.10/people/nicholson/papers/afenv80.pdfA lot of climate change due to atmospheric circulation change without CO2 forcing/sensivity.
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Post by icefisher on Jul 1, 2010 22:20:47 GMT
Well in most aspects of my life I am not gullible - eg. I've never invested in the stock market , and while I'm ignorant, my stand concurs with that of many people who are patently bright.
You mean you stood with other bright people who did not invest in the stock market. Sorry couldn't resist!!
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