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Post by sigurdur on Feb 1, 2012 1:55:45 GMT
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Post by steve on Feb 1, 2012 13:27:51 GMT
Icefisher, I meant to say "net rate of energy change at the surface". What distracted me was the fact that I'd used an example of why radiation models were needed in forecast models to calculate the rate of cooling at night.
Either way, whether talking about cooling, warming or staying the same temperature, the radiation emitted by the atmosphere and received at the earth's surface needs to be included in the equation.
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Post by numerouno on Feb 1, 2012 13:38:44 GMT
Steve I wonder if you could verify my thinking on the term "insulation"? People might think differently in different cultures, but I understand "insulation" means a practical and literal gap in thermal conductivity. When Icefisher talks about "insulating gases", as if as a matter of verified fact, I can't figure out a situation where they would actually form physical bands of less conductivity, as convection forces are constantly at work (at least underneath the tropopause). Even if there were theoretical 100% concented bands of such gases, what would they mean in terms of conductivity? They are, we hear, trace gases after all. Just a need to check out the densities?
If Icefisher is basing his non-greenhauz theory on the popular Internet meme of "colder objects can't warm warmer ones", his theory can be simply discredited right away. The trouble with theories such as his, is that they are basically public domain internet memes that have been "pimped up" to suit a person's own particular taste.
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Post by steve on Feb 1, 2012 13:52:37 GMT
numerouno, without reviewing the thread (so hopefully remaining relatively unbiased), insulation has an official physical definition that relates only to the transmission of heat via conductivity.
Insulation also has a common meaning which can be applied to just about anything (emotions, effects of economic damage etc. etc.) so one *could* use the term "insulating gases" to simply explain that the existence of the gases "insulate" in a "common sense" the earth's surface from the coldness of outer space.
If one is trying to have a discussion about the physics, though, one should be more careful about definitions, and one should not read too much into what others say if they use terms loosely.
I've struggled to understand icefisher's theory which is why above I stopped reading when I picked up what I saw as the first misunderstanding. In previous similar discussions, I've offered him a "simple model" in computer code that I hoped would enable him to see that even if you have a system where net energy can only go from warm to cold, you can still have a system in which an increase in the insulating and/or opaqueness of layers will lead to the layers closer to the heat source becoming warmer (because they cool more slowly).
(For the earth, the layer closer to the heat source is really the surface because the sun's rays mostly penetrate the atmosphere and are absorbed at the surface.)
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Post by icefisher on Feb 2, 2012 0:55:32 GMT
Icefisher, I meant to say "net rate of energy change at the surface". What distracted me was the fact that I'd used an example of why radiation models were needed in forecast models to calculate the rate of cooling at night.
Either way, whether talking about cooling, warming or staying the same temperature, the radiation emitted by the atmosphere and received at the earth's surface needs to be included in the equation.
We are not in disagreement on that.
Where we are in disagreement is in a passive solar water heating system a temperature gradient in the system is almost non-existant during times of the day when the system is peaking. Convection kills or more correctly minimizes the gradient.
At night when the coils cool a large temperature gradient forms between the water in the collectors and the water in the storage system.
As the night progresses conduction slowly cools water from the bottom up. The tank being insulated loses little out the top.
The average water in the tank is warmer than the average ambient temperature. It would not be under a uniform radiation condition. It would not be if the storage cooled at the same rate as the collectors.
Requirements for this system: 1) gravity to move expanded liquids or gases up and colder ones down. 2) a liquid or gas medium capable of storing heat. 3) an input that oscillates, namely the sun coming up and going down. 4) a collector more efficient at gaining heat than the storage system is at losing it.
Result an increase in the storage medium temperatures.
Our land sky interface corresponds to this and has all these features.
1) gravity is common to both systems. 2) the atmosphere uses a gas, the hot water system uses water 3) the sun comes up and goes down each day for both systems. 4) the ground is closer to a blackbody than the atmosphere. The emissivity difference allows the collectors to collect and accumulate heat until the storage medium's total heat loss rate equals the collector gain rate.
So you claim there is something wrong with this, that I fail to understand something. Be specific.
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Post by icefisher on Feb 2, 2012 1:23:58 GMT
Where we are in disagreement is in a passive solar water heating system a temperature gradient in the system is almost non-existant during times of the day when the system is peaking. Convection kills or more correctly minimizes the gradient.
At night when the coils cool a large temperature gradient forms between the water in the collectors and the water in the storage system.
As the night progresses conduction slowly cools water from the bottom up. The tank being insulated loses little out the top.
The average water in the tank is warmer than the average ambient temperature. It would not be under a uniform radiation condition. It would not be if the storage cooled at the same rate as the collectors.
Requirements for this system: 1) gravity to move expanded liquids or gases up and colder ones down. 2) a liquid or gas medium capable of storing heat. 3) an input that oscillates, namely the sun coming up and going down. 4) a collector more efficient at gaining heat than the storage system is at losing it.
Result an increase in the storage medium temperatures.
Our land sky interface corresponds to this and has all these features.
1) gravity is common to both systems. 2) the atmosphere uses a gas, the hot water system uses water 3) the sun comes up and goes down each day for both systems. 4) the ground is closer to a blackbody than the atmosphere. The emissivity difference allows the collectors to collect and accumulate heat until the storage medium's total heat loss rate equals the collector gain rate.
Now that I have this sukka figured out do you need an address to mail me my Nobel Prize?
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Post by icefisher on Feb 2, 2012 6:21:25 GMT
And of course this theory works quite nicely with variations.
For example the maximum average temperature the atmosphere could be, ignoring conduction out the bottom and a zero emissivity would be about 394k or 121C or about the maximum temperature the surface of the moon reaches during its 28 day long day.
It would be that hot due to no emissions from the atmosphere, no blocking of emissions from the sun, no water as that increases the emissivity, no clouds because of no water.
AGW theory believes everything hitting the surface would radiate to space. But to do that you would have to stop conduction and a warm surface is going to conduct to a cold atmosphere.
In fact it will continue to conduct until its probably over 100C as there is virtually no loss of heat. It would not balance sooner because of the presence of gravity and what it does with expanding gases and liquids.
It would stop at a max of 121C by virtue of having nothing hotter than that to input heat into the system. Remember you can only transfer heat if you have a store of heat and its hotter than where its going to go.
For the same reason it the heat pump would not operate with uniform radiation it cannot exceed the maximum radiation the sun shines on the earth either which is 1366 watts/m2.
There are a series of 5 threads on WUWT (starting Jan 13) with more than 4,000 comments.
These are somewhat related to the theory I present above that gravity is a big player in the greenhouse effect.
The thread comments center on whether gravity can do it alone.
The physicists made some good arguments that gravity could not do it alone but may have left something out that would allow gravity to do it (remember gravity attracts photons with Einstein's proof of bending light rays).
But nevertheless we don't have to depend on gravity doing it alone we have all the elements in the above machine that can do it. Gravity may not be a condition sufficient for warming a planet by putting an atmosphere around it with X heat content but it may be a condition necessary.
Its was interesting that all the counter arguments to gravity doing it alone was an argument a planet with only gravity to drive warming the lapse rate would break down and become isothermic.
But if that were true in this isolated system there would only be one place heat could come from to make the atmosphere isothermic and that would be by taking heat from the bottom of the atmosphere and putting it in the top.
Hmmm, sounds like at an equilibrium the surface is warmer than its average would be if the atmosphere was not in motion.
Fits kind of nicely with 60+ degrees temperature differential from top to bottom with an average of 30 degrees too much heat at the very bottom and 30 degrees too little at the very top. About exactly what the greenhouse effect is at this time.
So if in fact you need more than gravity you need an oscillating source of heat. Certainly our passive solar water heater needs this as well.
We also know what the atmosphere emissivity is from budget calculations. Cloudy skies are about .36 emissivity and the non-clouded sky is about .13 emissive for an average of .26 emissivity.
If you increase the emissivity of the atmosphere its going to cool faster. Where is it going to get the heat from?
Well if you increase emissivity remember half of solar incoming is longwave. So not only do you increase the emissivity of the atmosphere making it lose heat faster but you have less radiation hitting the surface.
Only in the bizarro world of backradiation can you imagine something to cause two colder things adding up to both being hotter.
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Post by icefisher on Feb 2, 2012 9:01:21 GMT
If you are discussing heat you need to understand the relative nature of the various "warmths" involved.
Iceskater, I design and build the damn things. If you want to drop by I will show you how they work.
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Post by icefisher on Feb 2, 2012 9:58:19 GMT
Yes i noticed you were totally unable to understand why a sheet of foil is such a poor insulator and instead you rambled on, as appears to be your habit, where nothing anybody else says makes any difference whatsoever to you.A sheet of foil is a good way to avoid heat loss. It may not technically be an insulator but it accomplishes the same thing. In my experience as a designer of passive solar systems you can lose heat two ways. 1) from conduction; 2) from radiation. Foil will deal with the radiation. If you don't believe that, like I say drop by, bring a thermometer and I will demonstrate it for you. You are the one now arguing that conduction is hugely important compared to radiation. Seems no matter what the subject you just like the contents of your own mind.Actually my belief, and I can't prove it, is that conduction and radiation are so similar that a perfect conductor for conduction is equal to an empty space for radiation. Makers of thermos bottles understand that. So they create a vacuum between between the walls and polish at least one surface. Meanwhile if you could leave me alone in peace here in this thread that i created, i will do you the same courtesy from now on in your own.they have a PM capability on this forum for private discussions Iceskater. I suppose the big beef has to be that you can't find anything wrong with the passive solar heating analogy either or directly deal with any of the assertion challenges I offered nonum. I have to admit I am appalled at climate science that they cannot discredit that mechanism. A physics teacher on WUWT just bowed out on it also. I mean its so damn simple that if it does turn out I am right on it, it will be the greatest boondoggle religious dogma scandal of all of mankind's history. And by the way. If you move two objects closer together in a radiation field they will get warmer. A variation of it is known as the George Hamilton suntan machine. Its a passive solar device. I have used it to get a suntan (like 45 years ago) and its an important element of passive solar design heat collection. But we are not talking here about moving the atmosphere closer to the surface so it does not apply in this instance.
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Post by icefisher on Feb 2, 2012 15:29:04 GMT
I am very confused as to what we are talking about here.
I already agreed that convective warming of the surface and radiation of that warmth back to the surface must be a factor in keeping the earth warmer.
I am confused by what you are thinking. Convection facilitates the cooling of the surface it warms the atmosphere taking heat from the surface.
You dismiss all of this however without answering my points
For example you just mentioned this hamilton effect. My observation was ignored
I just dont now what you are thinking or why you think it.
The George Hamilton suntan machine is when you lay out in your yard to get a sun tan you place a mirror nearby positioned so it shines on you.
I also find your writing style confusing.
Could you explain to me why my 'thought experiment' about two bodies in space where one is warmed is wrong according to your knowledge, beliefs and methods?
Did I say its wrong? If it were wrong the George Hamilton suntan machine would not work and I know it does as I got myself a suntan twice as fast with one mirror.
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Post by cnlmustard on Feb 8, 2012 3:56:04 GMT
I noticed this Graph, from the US Global Change Research Program (http://www.usgcrp.gov/usgcrp/images/Vostok.jpg) after reading a press release about the Russians, who successfully drilled down to Lake Vostok in Antartica this month. This thread has mentioned the Vostok ice cores a few times, and I thought it was odd that the CO2 values have a regular pattern to them on this graph. Is it naive or unrealistic to derive from this, that there is a natural cycle of CO2 on earth? (Note: I am NOT a scientist, and my comment is not sarcastic) Attachments:
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