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Post by socold on Apr 25, 2009 11:53:57 GMT
When you say that CO2 is a "driver" of climate change, I gather you are saying that the heat of the atmosphere increases in some way proportional to the quantity of CO2 in the atmosphere. In that case, Mars, which has an atmosphere comprised of 95% CO2, should have a warmer atmosphere than is recorded. Mars has about 12 times as much co2 as earth, but no water vapor. Given the amount of sunlight it absorbs, Mars should have an average surface temperature of about 215C, but it's actual average is about 225C making for a roughly 10C greenhouse effect, most of which comes from the co2 in it's atmosphere. You can see the big byte of IR absorption in Mars emission spectrum caused by the co2: www.xtec.es/recursos/astronom/mars/mgs/tese.htm
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Post by curiousgeorge on Apr 25, 2009 12:26:09 GMT
Here's another question I've had for some time. If we (people and related ) require such a razors edge environment for our physical and cultural well being (referring to the few degrees of temp swing and it's results that are claimed by the AGW argument ) then how have we managed to get to where we are today? We (Homo Sapiens ) have been around for ~250,000 years, so in terms of global warming (flooded cities, and other apocryphal consequences ), we've "Been there, done that, got the T-shirt" . I tend to think that people (physically, culturally, and otherwise ) are far more adaptable and robust, relative to environmental changes, than we are given credit for. We succesfully populate every corner of the globe, from the arctic to the tropics, and I personally have lived reasonably comfortably in both (without benefit of air conditioning, I might add ). Or is the argument more about maintaining an arbitrary economic "comfort zone" for a select few?
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Post by nautonnier on Apr 25, 2009 15:50:10 GMT
AGW Questionable Assumption 4" While a large volcanic eruption could have a negative forcing for a few years, there really isn't another negative feedback that is going to save us from the coming warming. There is much paleoclimate evidence that when the atmosphere held more carbon dioxide, temperatures were warmer and sea levels were higher. There is no evidence of a negative feedback that stabilizes the global temperature"I don't suppose you have read what you just wrote and realized the illogicality? If there is no negative feedback to stabilize the global temperature then Earth should be a sun-blasted rock like a hot Mars. There must be a negative feedback or once CO 2 causes the warming it would runaway. I want to question your logical analysis of what Ken said. I'm interested because I see this kind of obtuse analysis, or attempt to win an argument through flawed reducto absurdium a lot of times when debating with some sceptics. Ken referred to negative feedbacks that would "save us from the coming warming". In the context he's far more likely to be referring to warming in line with IPCC projections, rather than your fantasy runaway greenhouse effect. So is it fair to interpret him in this way just to try and win a debating point? I was mainly replying to his last sentence: " There is no evidence of a negative feedback that stabilizes the global temperature"
I don't think that you would support that statement either and it was why I suggested he read it again as there is plenty of evidence for many negative feedbacks and lack of such negative feedback _would_ lead to a runaway effect. So I am surprised that you call this a flawed analysis or a reducto absurdium - I think that you would agree that it is relatively primitive systems theory.
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Post by steve on Apr 25, 2009 16:17:47 GMT
I want to question your logical analysis of what Ken said. I'm interested because I see this kind of obtuse analysis, or attempt to win an argument through flawed reducto absurdium a lot of times when debating with some sceptics. Ken referred to negative feedbacks that would "save us from the coming warming". In the context he's far more likely to be referring to warming in line with IPCC projections, rather than your fantasy runaway greenhouse effect. So is it fair to interpret him in this way just to try and win a debating point? I was mainly replying to his last sentence: " There is no evidence of a negative feedback that stabilizes the global temperature"
I don't think that you would support that statement either and it was why I suggested he read it again as there is plenty of evidence for many negative feedbacks and lack of such negative feedback _would_ lead to a runaway effect. So I am surprised that you call this a flawed analysis or a reducto absurdium - I think that you would agree that it is relatively primitive systems theory. Context is important. It is quite clear that Ken is not saying that there is no upper limit to the warming.
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Post by nautonnier on Apr 25, 2009 17:26:32 GMT
I was mainly replying to his last sentence: " There is no evidence of a negative feedback that stabilizes the global temperature"
I don't think that you would support that statement either and it was why I suggested he read it again as there is plenty of evidence for many negative feedbacks and lack of such negative feedback _would_ lead to a runaway effect. So I am surprised that you call this a flawed analysis or a reducto absurdium - I think that you would agree that it is relatively primitive systems theory. Context is important. It is quite clear that Ken is not saying that there is no upper limit to the warming. Not what he said - sorry I am used to dealing with engineers who are precise in their language
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Post by donmartin on Apr 25, 2009 18:29:48 GMT
My information arises in the data provided by rovers and landers placed on Mars in the 21st century.
It seems to me that the density of atmosphere, which is a function of mass, is of greater significance than atmospheric composition in determination of heat content. Mercury is a planet of lesser mass than Venus or Earth, and has a cooler atmosphere than Venus. Venus, which is of a mass approximately equivalent to the Earth, has a much hotter atmosphere than Earth, but it is subject to a much greater solar IR than Earth. An excellent study along these lines is the atmospheric composition of Jupiter where density/mass/atmospheric heat content are correlative. In other words, it is arguable, perhaps, that distance from the Sun and mass have a greater bearing on atmospheric heat content than atmospheric composition, and indeed, atmospheric composition is a function of those two variables.
In respect of the atomic model, atoms, absorption, colliding, excitement, etc. I am mindful of the perfect beauty of Ptolemy's solar model. All one need do is believe in the little epicycles of certain planets, ignore the orbital recession of mercury, and everything was explained and our species was the centre of the universe. Fortunately, an inquisitive, scientific mind, namely, Copernicus, let loose the notion of infinity and the heliocentric model.
I will take a leap in thought. Perhaps every smallest point in space is a blackhole from which energy "escapes" and from which "mass" eventually arises. There is no such thing as an atom or molecule. And this may be why quantum gravity is posing such a difficulty.
And can anyone assist me in the following?: Is the greatest gravitational effect of the Earth experienced at the Earth's surface, and is there a horizontal gravitational force as one descends through the Earth?
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Post by donmartin on Apr 25, 2009 18:51:27 GMT
cg: Homo sapiens sapiens has been around for about 65 to 75 thousand years. We were "born", so to speak, in a period of glaciation, and the evidence now suggests we survived only by eating Neanderthals who had been around for a few hundred thousand years, were more intelligent than us, and were more physically suitable for the cold, but unfortunate for them, we could run faster than they could and we were likely a bit more aggressive. On the other hand, some believe our species survived due to our relationship with dogs, our hunting partners. So much for evolution.
In any event, and dogs notwithstanding, we have survived to now because we breed like rabbits in the face of driving ourselves to extinction through wars and idiotic behaviour. Also, we have technology which permits efficient conversion of energy to power. But we are about to eliminate that advantage unless saner heads, wherever they are, prevail.
The foregoing probably explains Fermi's paradox. We have been visited in excess of a thousand times by aliens from space, but it doesn't take a very intelligent alien to conclude they just have to wait us out in order to inherit a beautiful planet.
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Post by curiousgeorge on Apr 25, 2009 20:12:16 GMT
cg: Homo sapiens sapiens has been around for about 65 to 75 thousand years. We were "born", so to speak, in a period of glaciation, and the evidence now suggests we survived only by eating Neanderthals who had been around for a few hundred thousand years, were more intelligent than us, and were more physically suitable for the cold, but unfortunate for them, we could run faster than they could and we were likely a bit more aggressive. On the other hand, some believe our species survived due to our relationship with dogs, our hunting partners. So much for evolution. In any event, and dogs notwithstanding, we have survived to now because we breed like rabbits in the face of driving ourselves to extinction through wars and idiotic behaviour. Also, we have technology which permits efficient conversion of energy to power. But we are about to eliminate that advantage unless saner heads, wherever they are, prevail. The foregoing probably explains Fermi's paradox. We have been visited in excess of a thousand times by aliens from space, but it doesn't take a very intelligent alien to conclude they just have to wait us out in order to inherit a beautiful planet. I think you missed my point. Sometimes I fail to make myself clear. I won't argue the details of the many arguments surrounding evolution/religious/space alien/ad nauseum theories, since they've all been beaten to death and folks will believe whatever suits them. To clarify: I doubt we, as a species/culture, are as delicate as various people would have us believe. Or we wouldn't be here. We are survivors. There is something to be said about being at the top of the food chain. It follows therefore, that this hobgoblin of imminent catastrophic consequences if we do not address climate change by throwing mountains of money at it and lowering our standard of living, must be political/personal gain in nature. Whether it's due to deliberate malfeasance, ignorance, ideology, or some other incentive/motive, is debatable . Are you familiar with Marvin Harris' work? (Cannibals and Kings ) . Cultural anthropology.
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Post by FurryCatHerder on Apr 26, 2009 5:52:28 GMT
George, We're rily smart, but every other species (except dolphins ) is dumber and less able to adapt.
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Post by nautonnier on Apr 26, 2009 10:45:06 GMT
George, We're rily smart, but every other species (except dolphins ) is dumber and less able to adapt. Strange. Apart from some noticeable 'extinctions' that even humanity might have succumbed to - the other species appear to have been able to adapt well in the past - that's why they (and we) are here. Of course now that in many cases habitats are closely controlled and limited by human created borders - adaptation and moving to new areas can be difficult.
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Post by curiousgeorge on Apr 26, 2009 11:56:22 GMT
George, We're rily smart, but every other species (except dolphins ) is dumber and less able to adapt. You might get an argument from cockroaches and rats (among others ) about that. I'd say we (people) are clever, not necessarily smart. But that get's into definitions; and I've not heard from any unbiased arbiter on the subject. It's been said that the jury is still out on whether "intelligence" is a useful survival characteristic.
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Post by curiousgeorge on Apr 26, 2009 12:50:01 GMT
George, We're rily smart, but every other species (except dolphins ) is dumber and less able to adapt. Strange. Apart from some noticeable 'extinctions' that even humanity might have succumbed to - the other species appear to have been able to adapt well in the past - that's why they (and we) are here. Of course now that in many cases habitats are closely controlled and limited by human created borders - adaptation and moving to new areas can be difficult. Difficulty is the engine that drives adaptation/migration/evolution. Without it we'd all still be pond scum. You may also enjoy Marvin Harris' book's on cultural anthropology that I mentioned earlier. He provides some excellent insights into what drives us to do the things we do.
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Post by nautonnier on Apr 26, 2009 13:01:20 GMT
Strange. Apart from some noticeable 'extinctions' that even humanity might have succumbed to - the other species appear to have been able to adapt well in the past - that's why they (and we) are here. Of course now that in many cases habitats are closely controlled and limited by human created borders - adaptation and moving to new areas can be difficult. Difficulty is the engine that drives adaptation/migration/evolution. Without it we'd all still be pond scum. You may also enjoy Marvin Harris' book's on cultural anthropology that I mentioned earlier. He provides some excellent insights into what drives us to do the things we do. Well cultural anthropology may be interesting - but evolution tends to be a bit of a blunt instrument and if you are of a genotype that cannot resist say the 'swine flu' then intelligence and culture may not be enough. I always felt rather than being called 'survival of the fittest' it should have been called 'death of the least fit' These are not the same thing.
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Post by steve on Apr 26, 2009 13:06:00 GMT
Context is important. It is quite clear that Ken is not saying that there is no upper limit to the warming. Not what he said - sorry I am used to dealing with engineers who are precise in their language It's alright being critical of Ken's imprecise language (it's a forum post, not a dissertation), but it is you who drew the out of context conclusion. The precision has to be both in the writing *and* the reading
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Post by curiousgeorge on Apr 26, 2009 13:28:39 GMT
Difficulty is the engine that drives adaptation/migration/evolution. Without it we'd all still be pond scum. You may also enjoy Marvin Harris' book's on cultural anthropology that I mentioned earlier. He provides some excellent insights into what drives us to do the things we do. Well cultural anthropology may be interesting - but evolution tends to be a bit of a blunt instrument and if you are of a genotype that cannot resist say the 'swine flu' then intelligence and culture may not be enough. I always felt rather than being called 'survival of the fittest' it should have been called 'death of the least fit' These are not the same thing. Agreed. With both your comments. But it is an interesting discussion, yes?
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