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Post by speakertoanimals on Jun 17, 2011 12:42:37 GMT 1
And how's that supposed to keep it cool, it doesn't act like a fan you know.........................
Venus has a substantial atmophere, Mercury doesn't, go figure.............
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Post by speakertoanimals on Jun 17, 2011 12:57:30 GMT 1
So, you ADMIT you don't have the background, yet you still (based on personalities no doubt!) maintain your contrarian position.
And think that simulations are crap!
ALL of science to do with any complex system is based on modelling and PREDICTIONS to some extent. Predictions for starters because you make a prediction from a theory and then test it experimentally if you can.
You ASSUME that climate science can't do much the same thing. Except it CAN, and this paleoclimate stuff is one example.
Simulations is just another word for -- computations we could do by hand, but they would take an unfaesibly large amount of time, so we'll use a computer instead. It's the SAME sort of process that is used to design aircraft, or model any complex system, from a biological molecule, to the planetary movements in the solar system.
There is no other way to do science on such systems, given that our planetary engineering isn't up to building an alternate earth without greenghouse gases, and waiting to see what the difference is.
I will admity, I'm amazing that someone who speaks so confidently about the teeny amounts of CO2 involved could get atmosphere figures SO wrong, but at least you had the good grace to admit it.
You miss the point. We understand (WHY do I have to keep saying this!) the basis of variations in the earths orbit. Computing the change in the heat received by the sun is trivial. We understand the basic physics of the CO2 molecule, and why it should cause a greenhouse effect (despite the REAL nutters who claim it violates the second law of thermodyanmics!). Putting the two together to make a PREDICTION (using a model based on the actual physics) as to how we'd expect the temperature to vary during ice-ages is fairly trivial and tests our understanding of the basic physics.
then you test the prediction against the data, science 101.
ANY system in science nowadays involves some sort of modelling, and from a mathematical point of view, its everyday stuff, mathematical modelling. Doesn't mean it is automatically wrong.
Perhaps 'it's only a model' had come to be the new catechism of the deniers, akin to the 'its only a theory' of the creationists? Based on same problem -- c reationists don't understand the way that the word theory is used in science, and deniers who use that don't understand the models are used in almost ANY branch of science...................................
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Post by StuartG on Jun 17, 2011 13:22:26 GMT 1
"We understand the basic physics of the CO2 molecule" Fair enough, but we don't seem to understand that same molecule when it aggregated in the atmosphere in what is called 'positive feedback'. There doesn't seem to be any evidence that this is real. On the subject of 'computer modelling' of complex systems, You'll have to pardon the average person if they look at the Met Office weather predictions for the long term as an example. They might be better than they were, but apply that success back to 'climate modelling', which to many 'is the same only different' [applied to a longer time scale] and then add to that the need for our politicians to want to use this as a further 'tax excuse', You [royal You] have got a problem. StuartG
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Post by speakertoanimals on Jun 17, 2011 13:40:20 GMT 1
Except weather is much harder than climate, since climate is in effect, the long-term average! As regards planetary rotation -- okay, I'll admit I shouldn't have been quite that scornful, the rate of rotation averages out the temperature, but it's the average temperature that simple radiative physics tellls us. Another thing about Mercury versus Venus is that albedo -- Venus only absorbs about 35% of incident sunlight. SO, this is why it used to be thought that given higher albedo than earth, despite being closer to the sun, Venus should be at a temperature about the same as Earth. Except it isn't -- Venus is considerably hotter than earth, and hotter than Mercury, which is closer again. So,Venus only receives about a quarter of the sunlight that Mercury does, albedo ignored. Yet it's warmer than Mercury. So, a shame about all those old sci-fi stories which saw Venus as some sort of exotic wet jungle world! Venus also has a fairly SMALL temperature range, despite slow rotation, because of all that atmosphere. You can see a planetary scientists take on the greenhouse effect here, where a REAL runaway greenhouse effect would be the oceans boiling! cseligman.com/text/planets/atmosphere.htm
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Post by buckleymanor1 on Jun 17, 2011 14:01:03 GMT 1
Take a planet that don't rotate facing the sun and one that does. The planet that turns will radiate more heat into space as the face which was heated by the sun rotates towards space. The planet that don't rotate just gets hotter and hotter.
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Post by speakertoanimals on Jun 17, 2011 15:33:24 GMT 1
Take a planet that don't rotate facing the sun and one that does. The planet that turns will radiate more heat into space as the face which was heated by the sun rotates towards space. The planet that don't rotate just gets hotter and hotter. Okay, I guess what I should have said is that as far as I can judge, what is used is more like the average temperature, to account for the fact (this is an extreme case) where daylight and night sides are going to be different. Even for a planet that doesn't rotate, it will still radiate. And since radiation received from sun goes as cross-sectional area (pi r squared), whereas radiated heat goes as surface area (2/3 pi r cubed), means that you still get a temperature where incoming and outgoing balances. So, rotation (and atmopshere), just evens things out a bit. That still doesn't explain why Venus is hotter than Mercury, AND hotter than Earth........................ Other planets interesting as well -- we have simple prediction for Jupiter, say, but slightly hotter than that because Jupiter still contains quite a bit of heat from when it formed. This site will do an average temperature prediction: I would have tried it, but my machine going very slow today! Try for venus (star, 1 solar mass, distance 0.95, no greenhouse) and see what you get!
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Post by marchesarosa on Jun 17, 2011 19:43:05 GMT 1
Re Computer simulations of climate Comments from the Mark Lynas blog relevant to STA's lauding of computer climate models. Philip Bratby said: As physicist I disagree. The “greenhouse effect” theory does not stand up to scrutiny by physicists and there is evidence to support the theory. Computer models have no validity.
Barry Woods said I take real exception to having simulation runs described as experiments (without at least the qualification of ‘computer’ experiments). It does a disservice to centuries of real experimentation and allows simulations output to be considered as real data. This last is a very serious matter, as it can lead to the idea that real ‘real data’ might be wrong simply because it disagrees with the models! That is turning centuries of science on its head.
from the Mark Lynas blog www.marklynas.org/2011/06/questions-the-ipcc-must-now-urgently-answer/Good debate going, initiated by a green who is now alarmed by the IPCC!
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Post by principled on Jun 17, 2011 20:05:41 GMT 1
STA Oops After putting up such a strong defence for computer modelling...
the site you linked to keeps saying "You have typed a letter or some character into the Greenhouse box. retype the number and then press calculate". I did, but it didn't! They're a bugger these models, one minute they work and then next they don't!
P
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Post by StuartG on Jun 17, 2011 22:04:20 GMT 1
StA, I read Seligman's piece, it's well written for the layman, but it lacks something in the argument. 'Well what's it lack?" You might reply. Good question, If I could voice it I would. Not enough of the parameters that might be included, are. Something is being ignored. The amount of total energy from Sun to this planet is around 1300 kW/m² according to NASA/Kopp in Wiki en.wikipedia.org/wiki/Solar_radiation#Total_.28TSI.29_and_spectral_solar_irradiance_.28SSI.29_upon_Earth and it makes the same/similar point as Kirkby [poster-boy's fave] about UV. "Furthermore the Spectral Irradiance Monitor (SIM) has found in the same period that spectral solar irradiance (SSI) at UV (ultraviolet) wavelength corresponds in a less clear, and probably more complicated fashion, with earth's climate responses than earlier assumed". No doubt, at this point, You'll be throwing up Your arms. Further on in the article is states [on UV] "Ultraviolet B or (UVB) range spans 280 to 315 nm. It is also greatly absorbed by the atmosphere, and along with UVC is responsible for the photochemical reaction leading to the production of the ozone layer." Well now we are seeing the results of the 70's reaction to the 'Ozone problem' just recently it's been allowed to seep out that the Ozone 'hole'/thinning is still apparent [believed by 'moi' to be as a party result of 'Glopak'] Short comment We/They don't know enough to make such a judgement [yet]. Incidentally is it so that UV being 'higher up the scale is more energetic? than say visible light and IR. From the Wiki IR en.wikipedia.org/wiki/Infrared "Sunlight at zenith provides an irradiance of just over 1 kilowatt per square meter at sea level. Of this energy, 527 watts is infrared radiation, 445 watts is visible light, and 32 watts is ultraviolet radiation." From that we can see that Visible light has an energy input, what effect does this have. Little or none? One last thing, the picture with the fella with his ball, there's another lesson that can be drawn, notice how nice an shiny and a dapper chappie he is, especially considering his environment. You might like to ask Your scientific colleagues to study his lifestyle and then apply it when dealing with politicians, because this is really now 'Political'. Seligman says "Continental and sea ice will retreat and disappear, and sea levels will rise throughout our lifetimes, and the lifetimes of our descendants. And there is nothing that we can do, to prevent this. The only question is, what can we do to reduce these effects, and in some distant future, reverse them? " If it's that important, then the science of it and it application, is equally so, wrong decisions will be just as damning. StuartG
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Post by buckleymanor1 on Jun 18, 2011 0:19:42 GMT 1
Yes I can go with the fact that incoming radiation and outgoing radiation balances and is the same for a rotating planet and a none rotating planet over time. What is hard to accept is that a none rotatating planets temperature won't rise significantly more before it's outgoing radiation is the same as a rotating planet. The whole planet would act as a heat sink before radiating. Where as a rotating planet is dumping heat into space constantly.
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Post by speakertoanimals on Jun 21, 2011 12:37:28 GMT 1
Easy to make these claims, and easy to find a blog where they are stated. But that doesn't make them true! Greenhouse effect doesn't stand up to scrutiny by physicists? As a physicist, I disagree, and so do many other physicists. Who is this Philip Bratby? What are his reasons for claiming that physicists have a problem with the greenhouse effect? Without that information, this is just empty bluster (that could have just been made-up, frankly, without proper links and references we have no way of knowing...................) Is it this one: www.publications.parliament.uk/pa/ld200708/ldselect/ldeconaf/195/195we07.htmthat would be Phillip then.............. What he seems to be saying is that: So not doubting the greenhouse effect per se, just whether such seemingly low levels of CO2 can have the effect claimed. Plus a general attempt to disparage climate scientists for not being physicists, and presuming that they have got the physics of the greenhouse effect wrong in their modelling. Saying computer models have no validity is what you might expect from someonw who appears to be slightly aged (semi-retured energy consultant) -- the days are long gone when you could make a decent prediction using just pen and paper. I've read several of his posts on various sites, and its little more than a continued restatement of his BELIEFS on the matter, plus the old claim: Not that we are necessarily that interested in the results of polls, but is this true (depends what you mean by significant?). This claim is just a plain LIE. TO quote our own Royal Society: Try this Wiki page for various scientific organisations, plus similar pages for polls of scientists: en.wikipedia.org/wiki/Scientific_opinion_on_climate_change#Statements_by_dissenting_organizationsVery few? Given the FUSS that was made in the Royal Society when someone suggested something about evolution/creation in schools, IF a significant number of members of the Royal Society (or just british scientists in general) DISAGREED with this statement, they'd be jumping all over it. So, is he hiding behind the use of the word 'significant'? The rest of his statement, just empty, because despite him claiming that computer models aren't valid, what evidence does he advance that it WON'T cause such warming? None, he just repeats his opinion ad nauseam. P.S. I looked up Bratby at sheffield. Thesis title: The viscosity of liquid Ne20 and Ne22, the specific heats of liquids. from 1973. Hence probably knows diddly about computer models. What else can I find? CO2 is plant-food, climate has always changed, and the Met Office can't predict the WEATHER repeated ad nauseam as well, to conclude: It's just his belief, and he has even less evidence to support it than the evidence that he so disparages that supports AGW. Seems like a semi-retired slightly hoary ex-physicist from the punch-card days of computing................................ Rubbish as evidence. Just another semi-retired bloke with a doctorate who has got a bee in his bonnet -- could have been UFOs or something, he just happens to have chosen the great AGW conspiracy as his madness of choice.
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Post by StuartG on Jun 21, 2011 19:00:50 GMT 1
"the days are long gone when you could make a decent prediction using just pen and paper. " I expect You're correct, the variables seem complex with many yet unknown, it must be that Man has had an effect on the environment, after all 'England's green and pleasant land'* is down to us. It's another matter to take all the modern 'evidence' without a whimper and allow the resultant rules, regulations and laws to be enacted on such thin evidence. So incorrect conclusions drawn from uncertain science, [uncertain science in that some of the variables are not known or not sufficiently shown] will lead us down to something just as bad. Leglislation made in the light of unclear facts will be bad leglislation. The document that has been found is entitled "The Economics of Renewable Energy - Economic Affairs Committee" ...see the bit on the end 'Economic Affairs Committee' that should tell You why there are no real scientific references, if on the other hand it had been to the "The Parliamentary and Scientific Committee" www.vmine.net/scienceinparliament/ then some might be expected. Back to the report under discussion "The Economics of Renewable Energy - Economic Affairs Committee Contents " as may be seen the title has been extended in this latest paste and it contains the word 'Contents' if this is 'tapped on' a new page appears entitled "Economic Affairs - Written Evidence The Economics of Renewable Energy" there will be found all the written evidence submitted to the Committee under this subject, taking the first reveals "Memorandum by Professor Andrew Bain" who says "I am a semi-retired professional economist" but I expect He still knows 'how many beans make five'. further down there's one from the "Memorandum by Bishopton Village Hall Management Committee ". So You see it's not a scientific committee, it's economics. These are people's opinions including the "semi-retired slightly hoary ex-physicist from the punch-card days of computing" How would it be if the designers of the ""Porsche Semper Vivus (always alive), an all-wheel drive, petrol-electric hybrid with hub-centre electric motors in the front wheels "" where brought back from 1900, would their far sightedness be now dismissed as as "resurrected grease monkeys from the dog cart days of motoring"? radio4scienceboards.proboards.com/index.cgi?action=gotopost&board=politics&thread=248&post=12346StuartG ps. I know diddly about computer models. * www.nationalarchives.gov.uk/utk/england/land.htm
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Post by principled on Jun 22, 2011 9:49:15 GMT 1
Hi Stu Thanks for the link. The report on the Economics of Renewable Energy makes sober reading. It would seem from the report that our masters have decided to take us into totally uncharted waters in terms of the amount of non-firm renewable energy that the grid will need to deal with. The costs of the doubling of the necessary "spinning back up" needed to cope with this variability are truly eye watering. Then one sits back and looks at what entering into this experiment (for that is what it is) means in global terms, well a saving of about 0.8% of the world's output of CO2. This saving will be swallowed up by China's INCREASED CO2 output in about 5 months. One can only assume that self-flagellation and beating one's chest whilst reciting Mea Culpa are part and parcel of the British character, otherwise none of it make sense.
P
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Post by StuartG on Jun 22, 2011 12:09:23 GMT 1
p. I'm glad You see the logic, or the lack of it. "self-flagellation and beating one's chest whilst reciting Mea Culpa are part and parcel of the British character" You can assume that, but I would contend that it's not the 'British Character' but that of the trendy, wine supping, types who populate the 'meejah'. The Act-tors, 'personalities', and those who consider themselves 'international citizens'. Trouble is with those they are usually found wanting under closer scrutiny, with examples of arriving by 'air' or gas guzzler at conventions to make the point. If we are to believe the 'science' so far, and the climate is to change, then it is better to let it be so, for the moment. Wait until the science is better understood, and more of the variables are known. Meanwhile 'white - van - man' on £7.30/hr is expected to foot the bill, and for what gain to Him? Quote from #93 'Seligman' "But if you are concerned about the "fate of the Earth", or the future faced by your children and grandchildren, then perhaps it would be better to do what you can to use less energy, and to convince your representatives to vote for measures which would make it easier for you to use less energy, than to seek ways to burn more and more fossil fuels at a faster and faster rate. Or, if it seems too painful to do anything, you could do nothing. For many lifeforms, such as mosquitoes and millipedes, crocodiles and cockroaches, molds and mildews, a warmer, wetter Earth would be marvelous. It just depends upon whom or what you want to inherit the Earth. " Quote that to 'yer man in the van' and He'll look at You with disbelief mixed with 'comprehension climax', "Whaat?" .. "Well" You say, "how about 'the future faced by your children and grandchildren' He replies with a smile, "That's up to them, I've got my work cut out, just paying for them now, are You on a different planet mate, spouting all that stuff?" Consider my hero from #92, He makes little fuss, does a valuable and messy job, and manages to keep Himself pristine whilst doing it. If I sound socialist, I'm not, just trying to see what facts are around whilst trying to roll the rest of the garbage into a ball. [and trying to stay pristine] www.youtube.com/watch?v=zQjxamBe03Min this video is a another lesson 'the bigger Your balls the better Your chances' StuartG
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Post by speakertoanimals on Jun 22, 2011 14:11:04 GMT 1
This is rather a different argument to trying to diss the science per se (or even the totally mad route of trying to claim the greenhouse effect per se violates the second law of thermodynamics!).
SOME variables not being known is why, as I understand it, practioners run simulations with a RANGE of parameter values. We also have different people running different models. They aren't hiding the complexity, but in effect (in my perhaps naive view), undertaking an investigation of the space of possible climate models and climate scenarios, trying to investigate enough of the space to estimate how likely it is that we are destined for some nasty further warming.
Much of your objections seem to be about politics, rather than science. The SCIENCE may be clear, but unfortunately a somewhat simplified version has to be presented to the masses (not helped by the fact that many arts-educated politicians are scientifically illiterate). What sells the deal politically is often a very warped version of the actual science, and just because the publicity material is warped, doesn't mean the actual science is.
My judgement so far is that the science isn't as uncertain as some would like us to believe. And the science certainly isn't WRONG for any of the naive and misunderstood reasons that M would have us believe!
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