Global Mean Temperature

[palerider]

I am so surprised you still don't understand the radiation physics involved.

Clearly, it is you who doesn't understand the physics of radiation. It is you who believes in the multiplication of energy. It is you who believes that energy can be somehow created from nothing. You made that perfectly clear when you said:

I say the temperatures of the two hotplates will both rise until they are hot enough that the BB radiation at the higher temperature becomes 14,000 watts per centimeter. That will again achieve thermal equilibrium, and the total radiation flux will be 2000 watts, and the system will no longer rise in temperature. In reality the whole thing will melt before equilibrium happens.

It is you who believes that two hotplates at a temperature of 150 degrees will somehow generate so much heat that they will both melt even though the amount of electricity flowing into them is only enough to raise their respective temepratures to 150 degrees. You believe in a fantasy and completely disregard the laws of physics in favor of that fantasy. Do feel free to drop by Wally World and pick yourself up a couple of hotplates. You can get them for about 15 dollars each. Get yourself an infrared thermomenter from lowes and try the experiment yourself. What you will see is that the temperature of the heating elements will not raise.

How many crazies over the years have tried to somehow get more energy out of a system than they put in? The experiments always fail. If you were able to raise the temperature of either element above 150 degrees you would be creating energy. Raising the temperature enough to melt the whole system would give you enough excess to power a steam engine.

 

[Lagboltz]

Clearly, it is you who doesn't understand the physics of radiation. It is you who believes in the multiplication of energy. It is you who believes that energy can be somehow created from nothing. You made that perfectly clear when you said ...

If you don't believe my calculation, show me where conservation of energy was violated. I always said 2000 watts in, and 2000 watts out.

It is you who believes that two hotplates at a temperature of 150 degrees will somehow generate so much heat that they will both melt even though the amount of electricity flowing into them is only enough to raise their respective temepratures to 150 degrees. You believe in a fantasy and completely disregard the laws of physics in favor of that fantasy. Do feel free to drop by Wally World and pick yourself up a couple of hotplates. You can get them for about 15 dollars each. Get yourself an infrared thermomenter from lowes and try the experiment yourself. What you will see is that the temperature of the heating elements will not raise.

How many crazies over the years have tried to somehow get more energy out of a system than they put in? The experiments always fail. If you were able to raise the temperature of either element above 150 degrees you would be creating energy.

Now, now Pale. Calm down. Unbridled vitriol is hardly a substitute for a simple high school physics exercise. You are avoiding some simple math. Really, it is simple. You said you understand science so let's see the numbers. In your calculation be sure not to confuse energy with energy density, and please recognize that energy is incessantly being pumped into the system at 2000 watts. I know it's hard for you to believe the results right now, so prove it to yourself that your gut instincts are right. That is what any objective scientist would do, especially with such a simple exercise. C'mon, you can do it.

If you were able to raise the temperature of either element above 150 degrees you would be creating energy.

Don't forget Pale that the energy isn't being created, it is continually being supplied by the power cord and pouring into the system at 2000 watts, and if that 2000 watts can't get out quickly, what do you think happens with the temperature.

Raising the temperature enough to melt the whole system would give you enough excess to power a steam engine.

Sure, the hotplates could power a steam engine if you wish, but only at 2000 watts.

P.S. You still haven't shown a physics principle where two photons can annihilate each other. That is a fundamental premise for your gut feelings to be valid.

 

[palerider]

P.S. You still haven't shown a physics principle where two photons can annihilate each other. That is a fundamental premise for your gut feelings to be valid.

Subtraction of vectors explains where the photons go. You, on the other hand haven't shown that photons are anything more than the radiation that makes up an EM field and we know beyond doubt that EM fields can cancel each other out.

 

[Lagboltz]

Subtraction of vectors explains where the photons go. You, on the other hand haven't shown that photons are anything more than the radiation that makes up an EM field and we know beyond doubt that EM fields can cancel each other out.

I think I finally see what your problem is. You are thinking of static electric fields. Yes those fields can add or subtract, but do not involve photons.

We are talking about black body radiation -- electromagnetic waves. Those are not static fields. The waves you want to subtract are moving in opposite directions in the hotplate example but there is no principle that says they can completely cancel.

I'm disappointed in you. You didn't show any math. You still need to answer the question:
Energy being supplied by the power cord is continually pouring into the system at 2000 watts, and if that 2000 watts can't get out sufficiently through the gap, what do you think happens.

Sure, there is the particle-wave duality, but using that to say, "Subtraction of vectors explains where the photons go," would get you a failing grade in any physics course. Please go into detail and cite a source that has the same explanation. You must show a principle where photons can annihilate each other.

 

[palerider]

I think I finally see what your problem is. You are thinking of static electric fields. Yes those fields can add or subtract, but do not involve photons.

No, I am not thinking of static electric fields. And you just said that you can not subtract photons. The fact is that the very careful consideration that goes into the installation of every EM or infrared communications tower on earth is evidence that EM fields can interfere with, or cancel each other out. Destructive interference results in both fields being diminished and can result in the complete cancellation of one or both fields. If the field is diminished, or cancelled, tell me what you believe happens to the photons that the field is made of.

We are talking about black body radiation -- electromagnetic waves. Those are not static fields. The waves you want to subtract are moving in opposite directions in the hotplate example but there is no principle that says they can completely cancel.

And the Stefan-Boltzman equation is obviously the subtraction of two EM fields. Lets go through it again.

P= the radiated power. If T1 and T2 are equal, what is the amount of power being radiated?

I'm disappointed in you. You didn't show any math. You still need to answer the question:
Energy being supplied by the power cord is continually pouring into the system at 2000 watts, and if that 2000 watts can't get out sufficiently through the gap, what do you think happens.

The math is right there in front of you. If the radiation can't escape, then the EM fields cancel. If T1 and T2 are equal, what is the amount of power being radiated from one to the other?

Sure, there is the particle-wave duality, but using that to say, "Subtraction of vectors explains where the photons go," would get you a failing grade in any physics course. Please go into detail and cite a source that has the same explanation. You must show a principle where photons can annihilate each other.

Perhaps in an atmospheric physics course but then atmospheric physics is teaching a corrupted version of the SB law that classical physics courses don't, and never have taught.

And again, when vectors are subtracted, the EM field is diminished or cancelled. If the field is made of photons, where do you think those photons go when the magnitude of the field is diminished or cancelled. Photons represent energy. The diminishment or cancellation of one or both fields represents work being done. Energy is required to do work. Photons are, in fact, the energy that makes up an EM field. If the number of photons are not being diminished during destructive interference, then how can the field, in fact, be diminished. The number of photons describes the magnitude of the field. Lesser magnitude, fewer photons, greater magnitude, more photons. What do you think is being diminished when the magnitude of an EM field is diminished or a field is cancelled?

 

[Lagboltz]

.... And the Stefan-Boltzman equation is obviously the subtraction of two EM fields. Lets go through it again.

P= the radiated power. If T1 and T2 are equal, what is the amount of power being radiated?

The math is right there in front of you. If the radiation can't escape, then the EM fields cancel. If T1 and T2 are equal, what is the amount of power being radiated from one to the other?

If the temperatures are equal they radiate equal amounts of energy to each other. No radiation cancels. See the references below.

Perhaps in an atmospheric physics course but then atmospheric physics is teaching a corrupted version of the SB law that classical physics courses don't, and never have taught.

Classical physics has known about radiation physics for about a century.

And again, when vectors are subtracted, the EM field is diminished or cancelled. If the field is made of photons, where do you think those photons go when the magnitude of the field is diminished or cancelled. Photons represent energy. The diminishment or cancellation of one or both fields represents work being done. Energy is required to do work. Photons are, in fact, the energy that makes up an EM field. If the number of photons are not being diminished during destructive interference, then how can the field, in fact, be diminished. The number of photons describes the magnitude of the field. Lesser magnitude, fewer photons, greater magnitude, more photons. What do you think is being diminished when the magnitude of an EM field is diminished or a field is cancelled?

There are many references about EM radiation fields that disagree with you. Some are cited below. The first two say that radiation is still exchanged when the temperatures are the same. The third reference says that radiation is being exchanged, no matter what the temperature difference is.

http://en.wikipedia.org/wiki/Radiative_equilibrium
Planck (1914) refers to a condition of thermodynamic equilibrium, in which "any two bodies or elements of bodies selected at random exchange by radiation equal amounts of heat with each other."

http://quantummechanics.ucsd.edu/ph130a/130_notes/node48.html
"A black body is one that absorbs all the EM radiation (light...) that strikes it. To stay in thermal equilibrium, it must emit radiation at the same rate as it absorbs it ...".

http://en.wikipedia.org/wiki/Thermal_equilibrium
"One form of thermal equilibrium is radiative exchange equilibrium. Two bodies, each with its own uniform temperature, in solely radiative connection, no matter how far apart, or what partially obstructive, reflective, or refractive, obstacles lie in their path of radiative exchange, not moving relative to one another, will exchange thermal radiation, in net the hotter transferring energy to the cooler, and will exchange equal and opposite amounts just when they are at the same temperature"

How can you argue against all that and still maintain you understand radiation physics more than what is taught in physics courses? There is even a phrase in physics , "radiative exchange equilibrium," which is contrary to your post.

 

[palerider]

If the temperatures are equal they radiate equal amounts of energy to each other. No radiation cancels. See the references below.

If T1 and T2 are equal, P=0

Classical physics has known about radiation physics for about a century.

Yep, but it doesn't preach the existence of backradiation while atmospheric physics does. How long before they are teaching back conduction and back convection as well since they are as likely as backradiation?

There are many references about EM radiation fields that disagree with you. Some are cited below. The first two say that radiation is still exchanged when the temperatures are the same. The third reference says that radiation is being exchanged, no matter what the temperature difference is.

Wiki? Chuckle.

http://quantummechanics.ucsd.edu/ph130a/130_notes/node48.html
"A black body is one that absorbs all the EM radiation (light...) that strikes it. To stay in thermal equilibrium, it must emit radiation at the same rate as it absorbs it ...".

That statement assumes absorption. If T1 and T2 are equal, P=0. What is there to absorb?

How can you argue against all that and still maintain you understand radiation physics more than what is taught in physics courses? There is even a phrase in physics , "radiative exchange equilibrium," which is contrary to your post.

Show me a single repeatable, observable experiment that demonstrates backradiation from a cooler object to a warmer object.

 

[Lagboltz]

Yep, but it doesn't preach the existence of backradiation while atmospheric physics does. How long before they are teaching back conduction and back convection as well since they are as likely as backradiation?

Wiki? Chuckle.

The previous several posts concern a hotplate system example, which only considers radiative exchange equilibrium. That is a fundamental concept that you are disputing. You are now trying to distract that topic to different topics and simply answering with your usual mockery. Please stick to the current subject. Focus focus focus.

That statement assumes absorption. If T1 and T2 are equal, P=0. What is there to absorb?

You haven't been paying attention. Each plate is emitting and absorbing equivalent amounts of radiation energy from the opposite plate. That is what radiative exchange equilibrium is. You are disagreeing by saying there is no radiation because it cancels, and there are no photons being exchanged. That is the topic.

Show me a single repeatable, observable experiment that demonstrates backradiation from a cooler object to a warmer object.

You are digressing to a topic on a non-equilibrium condition. That is not the current topic. Please focus. You are denying radiative exchange equilibrium, and I am answering to that. Equilibrium is the simplest topic in radiative thermodynamics. If you can't understand that, then you can't understand any related topic.

Since you continually mock wiki, these three references are all from Nobel Prize winners and represent the current thought in thermodynamic equilibrium. Einstein's paper is in German, so the third citation is a reference to his ideas.

Wilhelm Wien Nobel Prize speech.
http://www.nobelprize.org/nobel_prizes/physics/laureates/1911/wien-lecture.html
"[Equilibrium state] ... taken as a whole for many atoms in the stationary state, the absorbed energy after all becomes equal to that emitted..."

http://ia700300.us.archive.org/28/items/theoryofheatradi00planrich/theoryofheatradi00planrich.pdf
Max Planck's original paper, page 40:
"...it is evident that, when thermodynamic equilibrium exists, any two bodies or elements of bodies selected at random exchange by radiation equal amounts of heat with each other..."

http://physics.ucsc.edu/~michael/ajpman1.pdf
"3. Extension of Albert Einstein's detailed balance argument to stochastic variables:
... Even in thermal equilibrium, transitions associated with the absorption and emission of photons are occurring continuously... "

All three references refer to radiation being exchanged between two bodies, and not radiation being canceled.

Now it's your turn. Show me some references that say that radiation cancels between objects in thermal equilibrium, and that no photons are exchanged between such bodies.

 

[palerider]

Please stick to the current subject. Focus focus focus.

I am afraid that it is you who has drifted off topic. We were discussing backradiation and whether or not the earth could be warmed by energy from the atmosphere. I believe the last pertinent question was whether or not you could provide a single observable, repeatable experiment that demonstrated that a warm object could be further warmed by a cool object.

Since you continually mock wiki, these three references are all from Nobel Prize winners and represent the current thought in thermodynamic equilibrium. Einstein's paper is in German, so the third citation is a reference to his ideas.

Aren't algore and obama nobel prize winners? Chuckle.

 

[Lagboltz]

I am afraid that it is you who has drifted off topic. We were discussing backradiation and whether or not the earth could be warmed by energy from the atmosphere. I believe the last pertinent question was whether or not you could provide a single observable, repeatable experiment that demonstrated that a warm object could be further warmed by a cool object.

Aren't algore and obama nobel prize winners? Chuckle.

I'm sorry but the pertinent question has been on thermodynamic equilibrium since post 66. We are now on post 85.

How can we possibly discuss thermodynamics of any kind when you can't even understand the most fundamental principle of radiative equilibrium. You continually were not able to tell the difference between power in watts and the power density in watts per square inch. You continually could not distinguish between the properties of coherent radiation and incoherent radiation. These topics are very pertinent to the discussion and should be very simple for anyone slightly adept in science.

So you chuckle off the work of top physicists of the last century simply because they got a Nobel prizes in physics and you compare them to the Nobel peace prize? That is simply juvenile. If you are adept in science like you claim you are, I certainly don't see it in your posts. This discussion with you is like an argument with a sullen 7 year old that has an attention deficit disorder when he is not blocking his ears.

Don't forget to do the light bulb experiment where there would be a black column between the bulbs due to canceled radiation if your theory is correct.

Again, show me some references to support your claim that that radiation cancels between objects in thermal equilibrium, and that no photons are exchanged between such bodies. You can't continue an argument in physics until you do that.

 

[dogtowner]

first we wander down a swimming pool tangent, now a hotplate tangent.

I really would like to hear an answer to the question PR poses.

 

[Lagboltz]

first we wander down a swimming pool tangent, now a hotplate tangent.

I really would like to hear an answer to the question PR poses.

Do you really think that would have any value when he doesn't understand radiation physics?

 

[dogtowner]

Do you really think that would have any value when he doesn't understand radiation physics?

yes.

if there is a way that this happens without violating physical laws, lets hear it.
when you start with a statement that directly contradicts the 2nd law of thermodynamics thats not the be3st first stab.

 

[Lagboltz]

yes.

if there is a way that this happens without violating physical laws, lets hear it.
when you start with a statement that directly contradicts the 2nd law of thermodynamics thats not the be3st first stab.

I actually was on the topic that you suggested in Post 56 where I say,

1. Radiant energy flows from a cold body to a hot body.
2. Simultaneously radiant energy flows from the hot body to the cold body.
3. The net energy flow is always from the hot body to the cold body. (2nd law)

My statement is very similar to this statement held by all scientists in thermodynamics.
http://en.wikipedia.org/wiki/Thermal_equilibrium

"One form of thermal equilibrium is radiative exchange equilibrium. Two bodies, each with its own uniform temperature, in solely radiative connection, no matter how far apart, or what partially obstructive, reflective, or refractive, obstacles lie in their path of radiative exchange, not moving relative to one another, will exchange thermal radiation, in net the hotter transferring energy to the cooler, and will exchange equal and opposite amounts just when they are at the same temperature"

The words in red in the quote are what I was saying in statements #1 and #2. The words in blue are equivalent to my statement #3. When I made those statements Pale was bent out of shape and couldn't understand the simple hotplate explanations that followed. Believe me the hotplate example is not a digression. It is fundamental concept to any discussion of backradiation.

 

[dogtowner]

I actually was on the topic that you suggested in Post 56 where I say,

My statement is very similar to this statement held by all scientists in thermodynamics.
http://en.wikipedia.org/wiki/Thermal_equilibrium

The words in red in the quote are what I was saying in statements #1 and #2. The words in blue are equivalent to my statement #3. When I made those statements Pale was bent out of shape and couldn't understand the simple hotplate explanations that followed. Believe me the hotplate example is not a digression. It is fundamental concept to any discussion of backradiation.

Saying somebody else believes something to be true is not the same as explaining what was asked.

2nd law says that flow from cold to hot is not possible without without external work being performed on the system.

so whats the external work ? and how does it allow CO2 to redirect energy that passes through it at near the speed of light ? I know that there are no swimming pools or hotplates out in the atmosphere so lets steer clear of them please.