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Post by glc on Jan 31, 2011 18:00:16 GMT
If positive feedbacks are dominant, then how did the earth get out of an ice age and not become a frozen wasteland ad infinium?
Just because a feedback is positive it doesn't necessarily mean that the output increases 'ad infinitum'. For example, the following series tends to a value of 2, i.e. it is a finite number.
1 + 1/2 + 1/4 + 1/8 + 1/16 ............
In climate the effect is that a new equilibrium is reached.
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Post by dontgetoutmuch on Jan 31, 2011 19:01:23 GMT
Fair enough. But the first statement wasn't flippant and is very important. Restated as a question: If feedbacks are negative (i.e. sensitivity is very low) then how did the earth enter (and come out of) the ice ages? The flippant answer is of course flatulence. (Mammoth, Al Gore, what have you) Lemme 'splain... See in the beginning Gaea was a wonderful place, then she developed a bad case of parasites... Life. The cause of all warming on Gaea is of course life. Yes the sun does play a small part, but the heat is mostly caused by evil life. (And please shut up you useless deniers, we have heard enough from you...) More precisely the warmth is caused by gas emitted by life. As everyone knows warmth is bad. (At least for Gaea, and that is what matters here.) in the beginning there was no flatulence... then life began and farts happened. This is how it works... 1. Gaea gets a bad case of life. 2. Life passes gas. You don't think so? Then hold your breath til the feeling passes. 3. The Gas traps heat and the planet warms. 4. Warmer planet = bigger and more life = more gas. 5. Has the planet reached the tipping point when the warming causes cold, blizzards, rain, snow, droughts, usual weather, unusual weather, all weather? If so skip line 7. 6. Loop to 2. 7. The tipping point has been reached, the extreme heat causes many areas to freeze and much snow leading to an ice age. 8. This destroys much of the current crop of parasites. (Life, humans that sort of thing.) As life dies off, the warming blanket of gas thins out and Gaea cools causing the ice to melt. 9. Loop to 2. Simple. The solution is of course for everyone to (In an environmentally safe method.) Stop emitting gas... permanently. Or for three easy payments of 10% more then you have, and of course all of your freedoms. I and my watermelon friends can offset your emissions by enriching ourselves to the point where the tipping point will not be reached. Trust us, we have done the math for you... |
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Post by AstroMet on Feb 1, 2011 0:42:27 GMT
If positive feedbacks are dominant, then how did the earth get out of an ice age and not become a frozen wasteland ad infinium? Just because a feedback is positive it doesn't necessarily mean that the output increases 'ad infinitum'. For example, the following series tends to a value of 2, i.e. it is a finite number. 1 + 1/2 + 1/4 + 1/8 + 1/16 ............ In climate the effect is that a new equilibrium is reached. The earth emerged out of the ice age the way it always does - by the activities and conditions of the Sun. |
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Post by steve on Feb 1, 2011 10:39:28 GMT
So why do the ice age cycles align with the Milankovitch cycles? A scientific argument would be more interesting than a pronouncement that it is because it is.
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Post by glc on Feb 1, 2011 10:44:46 GMT
The earth emerged out of the ice age the way it always does - by the activities and conditions of the Sun.
So what aspect solar activity caused the earth's temperature to drop by more than 5 degrees.
I'd like to see some actual calculations rather than your usual, long winded, hand waving.
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Post by steve on Feb 1, 2011 12:21:49 GMT
Yes with some "real math" please.
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Post by AstroMet on Feb 1, 2011 21:58:54 GMT
The earth emerged out of the ice age the way it always does - by the activities and conditions of the Sun. So what aspect solar activity caused the earth's temperature to drop by more than 5 degrees. I'd like to see some actual calculations rather than your usual, long winded, hand waving. You wouldn't even be able to comprehend my "calculations" Glc, since it is quite obvious that you cannot see that it is mathematically impossible for man-made global warming to occur on this Earth. Moreover, I continue to state that at no time has the ability to say for certain what the Earth's global temperature is now, or has been in the past, has been achieved. So stop playing with yourself. |
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Post by matt on Feb 1, 2011 23:17:34 GMT
You wouldn't even be able to comprehend my "calculations" At least you put calculations in quotes. |
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Post by AstroMet on Feb 2, 2011 3:47:53 GMT
If positive feedbacks are dominant, then how did the earth get out of an ice age and not become a frozen wasteland ad infinium? When the ice did melt, why didn't it continue until the oceans boiled away? It works both ways and why negative feedbacks lead to stability rather than out of control runaway climate. That is the natural order of things. It is only in post normal science that assumes climate is dominated by positive feedback. P.S. the use of "very low" is funny. The use of "dominant" is funny too. So feedbacks are high during changes in the cycle and low at the ends? Well maybe, but it is not a given! The last glacial maximum ended roughly 20000 years ago, so the ice albedo feedback managed to induce a warming of roughly 0.05C per 100 years (lower than I said above). So the climate *is* quite stable. But not so stable that the slight wobbles of the Milankovitch effect eventually turn the tide. But it isn't completely stable and it is easy to calculate that the changes due to adding CO2 are far more rapid than the average rate of ice gain or loss even leaving aside the feedbacks in addition to the albedo feedbacks that can be inferred. PS. Maybe we should take this onto arthur's thread and leave space for Jim to explain his understanding of G&T's 2nd law statements, and for astromet to show off with some integration over spherical coordinates. You would not be able to comprehend my spherical calculations since you are not knowledgeable about astronomic forecasting. It always amazes me how the fuzzy math proponents like to nickel-and-dime with their theories that do not have any meaning at all in the real world of climate and weather, but who go on as if they understand what causes these events on Earth. You cannot put the Earth's climate in a laboratory and test it. That is impossible. Nor can you possibly presume to use computer models to calculate changes in the Earth's climate. That is impossible as well, and this is the very reason why AGW is a total lie and has always been. You can go on and on with wanting to pick apart the Earth's climate and measure it to death searching for some "mechanism" that does not exist in the way you want it to. However, until you realize and accept what causes and forces the climate and weather you are simply wasting your time. No amount of fuzzy math is going to get you any closer to coming to terms with the truth of the matter. |
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Post by glc on Feb 2, 2011 12:42:21 GMT
You would not be able to comprehend my spherical calculations since you are not knowledgeable about astronomic forecasting.
Oooh! spherical calculations, eh. Why don't you take it slowly for us then we can ask questions as you go along.
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Post by AstroMet on Feb 2, 2011 19:56:58 GMT
You would not be able to comprehend my spherical calculations since you are not knowledgeable about astronomic forecasting. Oooh! spherical calculations, eh. Why don't you take it slowly for us then we can ask questions as you go along. You have been provided with the basics of astrometeorology, not only on this forecast thread, but on other posts on this forum Glc. I suggest you read them to learn rather than pestering me to take it *slowly* for you. I work for a living as a professional and you are not paying me to teach you astronomic forecasting. Moreover, your attitude and sniveling comments do nothing for you except to further close your already ideological mind to those things of which you lack knowledge. In order for you to use more than 10% of the power of your own brain you will need to unlearn that which you have learned and that effectively blocks you from learning more in order to access the remaining 90% of the brain power of which you are not using. |
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Post by magellan on Feb 2, 2011 20:11:23 GMT
If positive feedbacks are dominant, then how did the earth get out of an ice age and not become a frozen wasteland ad infinium? Just because a feedback is positive it doesn't necessarily mean that the output increases 'ad infinitum'. For example, the following series tends to a value of 2, i.e. it is a finite number. 1 + 1/2 + 1/4 + 1/8 + 1/16 ............ In climate the effect is that a new equilibrium is reached. you are not describing positive feedbacks. Negative feedbacks in nature strive for equilibrium. |
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Post by AstroMet on Feb 3, 2011 0:43:44 GMT
So why do the ice age cycles align with the Milankovitch cycles? A scientific argument would be more interesting than a pronouncement that it is because it is. Take a look out of your window and the world's real weather and climate. |
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Post by trbixler on Feb 3, 2011 2:52:25 GMT
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Post by glc on Feb 3, 2011 8:58:55 GMT
you are not describing positive feedbacks. Negative feedbacks in nature strive for equilibrium
You are confusing positive feedback with a "runaway" effect. Equilibrium was achieved during the ice ages - despite the fact that feedback must have been positive.
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