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Post by glc on Sept 6, 2009 10:06:42 GMT
Why not start with a model of clouds that move?
Why would you necessarily start there. Any change in the behaviour of clouds due to enhanced ghg is a feedback. On this blog we are still trying to establish that more CO2 is likely to result in warming.
Sunray shines and heats the unclouded ground, cloud moves exposing low emitting cold ground and covering warm ground.
Indeed - and for the time being we can assume that process will continue. First, though, we need to confirm that the a proportion of LW radiation (forget convection, conduction, latent heat) that is emitted from the earth's surface is absorbed by gases in the atmosphere. That's why ~390 w/m2 leaves the earth's surface but only ~235 w/m2 is emitted to space. That is why the average temperature of the earth is ~287K (14 deg C) rather than ~255k (-18 deg C)
If more absorbing gases are added to the atmosphere then it follows that more absorption will take place and the earth will get warmer. If all other factors remain constant then we'll get about 1 deg warmer. But it's not likely that all other factors will remain constant. This brings up the question of feedback of which there is much more uncertainty.
However, the uncertainty of feedback does not falsify the basic AGW theory. It just means there is a genuine argument over climate sensitivity. This is where I probably disagree with Socold and Steve.
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Post by socold on Sept 6, 2009 10:58:53 GMT
I just did, it's not very good. The second link is a lesson in nitpicking. Wow, you're a quick reader and no doubt thoroughly discredited everything he says. What exactly isn't very good? Laying down facts is nitpicking? Thanks, no I haven't discredited everything he says, I just note some of the points seem unwarranted. For example: "Yes, Gavin is aware of Lorenz’ butterfly. He fails to state, however, that the average prediction horizon of weather forecasts is comparable to the lifetime of synoptic weather systems. I would not mind this omission, were it not for the fact that the (unknown) prediction horizon of climate models is determined in part by the life time of circulation systems in the ocean, such as the Pacific Decadal Oscillation. Since weather models and climate models are conceptually similar, one must expect similar predictability problems." This would be a good point if climate models actually presented evidence of a prediction horizon after say 20 or even 50 years, but they don't. Models runs for the 21st century show a similar path even if initial conditions are slightly changed. In contrast weather model runs would diverge to the point of being useless after two weeks if initial conditions are slightly different between runs. So while it's a nice touch to play on Gavin's use of the term "conceptually similar", I think the evidence in this case is that in terms of prediction horizons weather and climate models are not similar.
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Post by woodstove on Sept 6, 2009 13:04:29 GMT
Oh, OK, glc -- how about "troll-like"?
I've seen you doubt the existence of the LIA on at least four or five threads. When you lose the argument you simply bring it up again later and waste a lot of people's time. This is troll-like behavior.
Whereas the LIA is well-established FACT in the annals of climatology, you keep on with the misdirection about realist climate scientists agreeing with you about a THEORY:
"Richard Lindzen, Pat Michaels, Jack Barrett (who has actually taken on the IPCC in debate), Garth Paltridge and numerous others all recognise that doubling CO2 (at equilibrium and with other factors constant) will result in a temperature increase of ~1 deg C." [emphasis added]
1. Show me one quote of mine saying that this is not the case. You say I've said it, so put your money where your mouth is.
2. More important, "at equilibrium and with other factors constant" honestly doesn't matter. If the Earth stopped turning, the coriolis effect would suddenly end, too, but only a fool would do a study on the highly significant risks attached thereto.
3. Your beloved modelers are DIVORCED from reality.
Mourning would be appropriate.
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Post by icefisher on Sept 6, 2009 18:05:50 GMT
Why not start with a model of clouds that move?Why would you necessarily start there. Any change in the behaviour of clouds due to enhanced ghg is a feedback. On this blog we are still trying to establish that more CO2 is likely to result in warming. Thats completely non-responsive! The existing cloud state is not feedback. You asked "Why don't we start by you explaining how the earth has managed to achieve an average temperature of ~287K (~14 deg C)." Sunray shines and heats the unclouded ground, cloud moves exposing low emitting cold ground and covering warm ground.Indeed - and for the time being we can assume that process will continue. First, though, we need to confirm that the a proportion of LW radiation (forget convection, conduction, latent heat) that is emitted from the earth's surface is absorbed by gases in the atmosphere. That's why ~390 w/m2 leaves the earth's surface but only ~235 w/m2 is emitted to space. That is why the average temperature of the earth is ~287K (14 deg C) rather than ~255k (-18 deg C) [/quote] You begged the question GLC! I was answering your question If more absorbing gases are added to the atmosphere then it follows that more absorption will take place and the earth will get warmer. If all other factors remain constant then we'll get about 1 deg warmer. But it's not likely that all other factors will remain constant. This brings up the question of feedback of which there is much more uncertainty. However, the uncertainty of feedback does not falsify the basic AGW theory. It just means there is a genuine argument over climate sensitivity. This is where I probably disagree with Socold and Steve. [/quote]
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Post by glc on Sept 6, 2009 18:47:03 GMT
I've seen you doubt the existence of the LIA on at least four or five threads. When you lose the argument you simply bring it up again later and waste a lot of people's time. This is troll-like behavior. I haven't lost any argument. I ask for the temperature observations that show the LIA existed and all I get are proxy reconstructions that show some places were cold for some of the time in the LIA period. These are proxy reconstructions which rely on the modern thermometer - a record which is generally rejected on this thread. You cite Akasofu, but his evidence is weak and relies on the long term european records - none of which support he so-called recovery after 1800. The CET record is flat through the entire 19th century. Uppsala is colder in the 1850s than in the early part of the century. Armagh nor De Bilt provide much support. Anthony Watts posted this article recently wattsupwiththat.com/2009/09/02/woods-hole-embraces-the-medieval-warm-period-contradict-manns-proxy-data/His intention was to cast further doubt on the Mann H-S. It did no such thing. The reconstruction shows only a small temeprature difference between the MWP and LIA. Mann's H-S actually has a greater range of temperature change. I have yet to see any evidence that there was a simultaneous cooling across the majority of world during the LIA.
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Post by woodstove on Sept 6, 2009 19:03:43 GMT
I've seen you doubt the existence of the LIA on at least four or five threads. When you lose the argument you simply bring it up again later and waste a lot of people's time. This is troll-like behavior. I haven't lost any argument. I ask for the temperature observations that show the LIA existed and all I get are proxy reconstructions that show some places were cold for some of the time in the LIA period. These are proxy reconstructions which rely on the modern thermometer - a record which is generally rejected on this thread. You cite Akasofu, but his evidence is weak and relies on the long term european records - none of which support he so-called recovery after 1800. The CET record is flat through the entire 19th century. Uppsala is colder in the 1850s than in the early part of the century. Armagh nor De Bilt provide much support. Anthony Watts posted this article recently wattsupwiththat.com/2009/09/02/woods-hole-embraces-the-medieval-warm-period-contradict-manns-proxy-data/His intention was to cast further doubt on the Mann H-S. It did no such thing. The reconstruction shows only a small temeprature difference between the MWP and LIA. Mann's H-S actually has a greater range of temperature change. I have yet to see any evidence that there was a simultaneous cooling across the majority of world during the LIA. NASA has several paleoclimatology papers on different websites that it runs that take the LIA for granted as a global phenomenon, and NASA is far from alone in this. Your view appears to be well-encapsulated in the following: 1. Proxies are not to be trusted, unless we are talking about Mann's bristlecone pine temperature reconstruction. 2. The Little Ice Age cannot be proven to have taken place. 3. Even though it did not take place, any recovery from it did not start in 1800 as Akasofu states but in the mid-20th century as Mann has so ably demonstrated. Do I have it yet?
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Post by icefisher on Sept 6, 2009 20:12:42 GMT
Why not start with a model of clouds that move?Why would you necessarily start there. Any change in the behaviour of clouds due to enhanced ghg is a feedback. On this blog we are still trying to establish that more CO2 is likely to result in warming. You are not paying attention GLC. I suggested that the initial state of clouds contributes to a warmer planet. . . .I am not addressing at all any differences in clouds created by changing levels of so-called greenhouse gases. Your question was: "Why don't we start by you explaining how the earth has managed to achieve an average temperature of ~287K (~14 deg C)." I agree thats an important question but we should not assume we know the answer until we do. Giving it some thought I have thought of about 3 mechanisms besides GHG. 1) conduction from an efficient blackbody to an inefficient non-ghg emitter (i.e. the surface warming the air above it and the air above it being a non-blackbody and a less efficient emitter of IR accumulates some degree of heat before hitting equilibrium) None of this has ever been quantified as near as I can tell. People have been focusing exclusively on efficient emitters and back radiation as opposed to considering the effect or potential emission delay of inefficient emitters. 2) low level LW IR absorption by the mass of non-ghg in the atmosphere. (really nothing is completely transparent). Again collecting heat in an inefficient emitter. This might seem unimportant except that we are talking about multiple factors of magnitude here in larger numbers of molecules so measurements of emissivity and emissivity efficiency would need to be very highly accurate to eliminate this route for initial warming of the atmosphere to 287k. Now these are two I did not provide as an answer because I have provided these to you in the past. But here is the one I did provide that you just brushed aside as a feedback. 3. Take a given level of clouds. Those clouds result in only 255k reaching the surface due to reflectivity. If the clouds stayed in one place the heat would be in equilibrium and an average of 255k would reflect back out to space (ignoring GHG and 1&2). But if the clouds move, which they do, they will uncover unheated ground and cover heated ground. Since the clouds are 100% opaque to LW IR (as opposed to GHG only being fractionally opaque) the clouds will now be absorbing those 4th power warmer emissions instead of the cold surface emissions that are cold because the clouds initially blocked those areas from getting SW to heat with. Nobody has measured or estimated this effect as far as I know. One would think one would need to pin the above down before attributing all planet warming to GHG. If I am off track here, provide some references please, not just a wave of your hand to make it go away. If more absorbing gases are added to the atmosphere then it follows that more absorption will take place and the earth will get warmer. If all other factors remain constant then we'll get about 1 deg warmer. Doesn't that assume all the initial warming from 255k to 287k is attributable to GHG? Logically that seems implausible for the three reasons I provided above.
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Post by icefisher on Sept 6, 2009 20:17:02 GMT
You cite Akasofu, but his evidence is weak Akasofu's work may not be ironclad but it sure beats the wool the warmologists try to pull over our eyes.
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Post by northsphinx on Sept 6, 2009 20:29:23 GMT
glc wrote "First, though, we need to confirm that the a proportion of LW radiation (forget convection, conduction, latent heat) that is emitted from the earth's surface is absorbed by gases in the atmosphere. That's why ~390 w/m2 leaves the earth's surface but only ~235 w/m2 is emitted to space. That is why the average temperature of the earth is ~287K (14 deg C) rather than ~255k (-18 deg C)" But there is no strange with that. But what have that to do with CO2 in reality? I belive You refer to this picture: disc.sci.gsfc.nasa.gov/oceancolor/images/energy_balance.jpgThere is one wrong with this picture though. Greenhouse gases is not the right word because tha make some people refere to CO2 and only CO2. Here is another similar picture with a better explanation: www.env.go.jp/en/wpaper/1994/eae230036000001.gif"Greenhous effect" Which is a natural effect mainly caused by H20 Good reading by the way: earthobservatory.nasa.gov/Features/EnergyBalance/page7.php"The exact amount of the energy imbalance is very hard to measure, but it appears to be a little over 0.8 watts per square meter." For CO2 And on page 3: earthobservatory.nasa.gov/Features/EnergyBalance/page3.php"Areas around the equator absorbed about 200 watts per square meter more on average (orange and red) than they reflected or radiated. Areas near the poles reflected and/or radiated about 200 more watts per square meter (green and blue) than they absorbed. Mid-latitudes were roughly in balance" A 0,8 w would make a difference? I dont think so in the reality. This -200 and plus 200 Wm-2 is balanced by the global water balance. Also a nice site: geography.uoregon.edu/envchange/clim_animations/And Please do not come with the CO2 forcing again due to more vapor in the atmophere because the equator is cooled by clouds and only the arctic is warmed by clouds. As the global water balance is a proof of. It is all about the clouds.
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Post by socold on Sept 6, 2009 20:56:59 GMT
Giving it some thought I have thought of about 3 mechanisms besides GHG. 1) conduction from an efficient blackbody to an inefficient non-ghg emitter (i.e. the surface warming the air above it and the air above it being a non-blackbody and a less efficient emitter of IR accumulates some degree of heat before hitting equilibrium) This doesn't provide any additional energy to the surface or reduce energy loss from the surface, so it cannot lead to a surface warmer than what direct sunlight can allow. I take it as a given that science has quantified the IR absorption of air without greenhouse gases. They don't need to move to have a warming effect. Clouds are part of the greenhouse effect, they are strong IR absorbers and also strong emitters. Im sure scientists have.
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Post by icefisher on Sept 6, 2009 21:18:15 GMT
Do you cast a few herbs in the pot when you say that?
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Post by socold on Sept 6, 2009 21:47:53 GMT
Do you cast a few herbs in the pot when you say that? Call it intuition, common sense, whatever but when a question that boils down to "have scientists ever tried shining IR light through a tube filled with only nitrogen and oxygen at varying concentrations?" comes along I think it's more than a safe bet that they have even if I don't know the whos and whens of specific studies that did it.
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Post by spaceman on Sept 6, 2009 21:48:40 GMT
the net effect of clouds at least on this planet, is cooling. The net from reflected energy back into space and what the clouds keep from escaping is negative. If anything increased cloud cover, caused by global warming, is a feedback to cool the earth. My disagreement is the cause of global warming. One is a cause and the other is a minor player. The unmoving belief that co2 is the only cause of global warming is certainly political. I asked 'if co2 is the cause of global warming, then what caused the LIA or the medeval warming period?' The response is it didn't happen! Of course not, the history of the world didn't start until 1978. How can we know whether anything happened at all? If science is reduced to this level, we don't need rational inquiring minds we need wizards and magic spells
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Post by poitsplace on Sept 6, 2009 23:22:20 GMT
Do you cast a few herbs in the pot when you say that? Call it intuition, common sense, whatever but when a question that boils down to "have scientists ever tried shining IR light through a tube filled with only nitrogen and oxygen at varying concentrations?" comes along I think it's more than a safe bet that they have even if I don't know the whos and whens of specific studies that did it. Yeah, obviously they Have. Heck, the tube even heats up some. Of course, the only limiting part of the atmosphere is the tropopause (the coldest and therefore lowest emitting part so far as CO2 is concerned) and GET THIS...some people have this crazy idea that making that region absorb more will somehow make it cool down and the regions that are emitting more warm up. Ain't that a hoot? They also believe that the part that will be made to get cooler...will radiate energy downward even more. Man the crazy things people believe.
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Post by icefisher on Sept 6, 2009 23:55:37 GMT
Do you cast a few herbs in the pot when you say that? Call it intuition, common sense, whatever but when a question that boils down to "have scientists ever tried shining IR light through a tube filled with only nitrogen and oxygen at varying concentrations?" comes along I think it's more than a safe bet that they have even if I don't know the whos and whens of specific studies that did it. Well besides picking the one study of at least 3 that would most likely have been done; common sense does not serve here. As common sense would say its not been done as most stuff has not been done. Intuition is something akin to faith. You should serve a few terms as an auditor and find out just how often stuff that should be done gets done. That would serve as an eye opener to your naivete. This is kind of like one of those arguments like how many angels can dance on the end of a pin. Socold and the IPCC say 1.5 to 4.5 . . .and Socold is convinced because no other scientist has built a model that demonstrates less. Yet when asked if the assumptions of his models might be imaginatory he replies that it is commonsense they are not. Charles Dodgson became wealthy writing about folks like you.
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