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#56123 - 06/26/16 09:03 AM Follow the photon! Is this right?
samwik Offline
Megastar

Registered: 10/10/06
Posts: 1164
Loc: Colorado
I'm hoping to turn a fairly off-topic reply into an interesting and instructive lesson in physics.
So here is an attempted description for radiative heat transfer, istm, related to a question from greenhouse theory.

Originally Posted By: paul
OK , I read the highly informative and scientific article
on the "NEW SCIENTIST" web site that you posted the link to.

Quote:
we know that co2 is a greenhouse gas because it absorbs
and emits infrared radiation , basic physics tells us that
gasses with this property trap heat radiating from the earth...


basic physics tells us the following about the above MYTH !!!

lets reduce this process down to a earth that has only 1
co2 molecule in the atmosphere.

tell me at which time in the following basic physics processes
does the earth or the atmosphere warm due to the co2 molecule in the
atmosphere.

where t = time interval
and E = added energy
Earth = the earth
Atmos = the earths atmosphere

t=1
Earth E = 0
Atmos E = 0

sunlight passes by the co2 molecule on its trip to
the earths surface because its frequency is different
from the co2 molecule.

t=2
Earth E = 1
Atmos E = 0

the sunlight is absorbed by an object on the earth.
at this point for a fraction of a second there is a
tiny amount of heat transferred into the object on the
earth.


t=3
Earth E = .5
Atmos E = 0

a fraction of a second later the object then emits
infrared light (a photon of light)
at this point the object retains some of the heat energy
that it initially received from sunlight.
because the object released energy when it emitted the infrared light


t=4
Earth E = .5
Atmos E = .5

the infrared light that was emitted from the object
is then absorbed by the co2 molecule in the atmosphere.
at this point the co2 molecule becomes excited and undergoes
a frequency change ... and it cannot absorb another photon
until it emits a photon of the same energy that it absorbed.
for a tiny fraction of a second the co2 molecule moves around
in the atmosphere faster than it did before it became excited
by the infrared light that was emitted from the object on the earth.

t=5
Earth E = .5
Atmos E = 0

the co2 molecule then emits a photon with the exact energy
that it absorbed.

so far during this process the earth has gained .5 energy from the
visible light not the infrared light as the energy of the infrared light
is emitted by the object.

the co2 molecule has not gained any energy and the atmosphere has not
gained any energy.

so where in physics can it be claimed that co2 causes any warming?

the energy that is sent into the atmosphere (infrared) is not stored.

it is immediately released mostly back into space or towards the earth again.

now suppose the co2 molecule emits its infrared photon towards the earth
and the infrared photon is absorbed by the object on the earth.

t=6
Earth E = 1
Atmos E = 0

the infrared light is absorbed by the object on the earth.
and almost immediatly the object emits a infrared photon with the exact same energy.

t=7
Earth E = .5
Atmos E = 0

the photon of infrared light emitted from the object
is now traveling to the co2 molecule that is in the atmosphere.

--------------------------------------------------------------

this process can never change in a way that will cause
any additional energy (heat) to be stored on the earth or
in the atmosphere.

and it does not matter how many times the process is repeated.

and adding more co2 molecules to the atmosphere will deliver the same
results per each co2 molecule added.

note: where the belief , thoughts or claims that co2 causes any warming at all
is in question everything , all evidence , every claim and every word that exist above
the basic fundamental physical processes involved are muted debunked and totally
refuted by basic physics.

also:

if you desire to claim that the time interval between
t=4 and t=5 where the co2 molecule moves around in the
atmosphere faster and that an interaction with other
particles and/or molecules in the atmosphere causes some
degree of heat to build in the atmosphere then you will
need to explain where the energy that causes the heat comes
from ... because the co2 molecule must release a photon of
the same energy that it absorbed.

and as we you all know
" you cant get a free lunch "
" you cant pull yourself up by your bootstraps "
and
" you cannot create energy "

etc ... etc ... etc ...but your welcome to try if you like.


Paul, this is an interesting description, and I have some ‘physics’ questions,
such as how molecules “must release a photon of the same energy” …or how an “object retains some of the heat energy …because the object released energy when it emitted the infrared light,”
which I’d like to ask about later.

Now however, I'd like to question your two claims, just based on your understanding (regardless of its validity) as you’ve described it here.

So, working from your description quoted above (after the initial sunlight is absorbed by the ground)
the process seems to boil down to this:
...
t=3 (IR photon emitted by ground)
t=4 (IR photon absorbed by CO2)
t=5 (IR photon emitted by CO2) [by chance “…towards the earth again.”]
t=6 (IR photon emitted by ground) [after ground absorbs IR photon from t=5]
t=7 (IR photon absorbed by CO2) [IR photon from ground might again be absorbed by CO2]

…and as you say, “it does not matter how many times the process is repeated.”
So, for instance, t=8 (same as t=5) …and [t=7 essentially the same as t=4].

So, potentially, we have this IR photon bouncing back and forth between the ground and a CO2 molecule …potentially for hours on end
…before the IR photon might finally “miss” the CO2 molecule and head blissfully out into deep space. Right?
===

But....
Heading out into deep space, for the IR photon, is what we call cooling of—or losing heat from—the planet.

Before the IR photon leaves the planet, especially while it is bouncing around down in the lower troposphere,
it will still function as heat if/when it hits a body or a thermometer. Won’t it?

This is why I question your two claims that “it does not matter how many times the process is repeated. and adding more co2 molecules to the atmosphere” does not matter either.

Wouldn’t anyone expect that “adding more co2 molecules to the atmosphere” would provide more chances
for the IR photon to get intercepted, and bounce back and forth between ground and any other CO2 molecules,
before finally getting lucky enough to head out into deep space, thus finally helping to cool the planet?

The more time that IR photons spend bouncing-back-n-forth near the surface,
the more chance those IR photons have of being sensed or detected as extra heat.
Despite the numbers you’ve (seemingly randomly) assigned to your “Earth E & Atmos E” designators,
that 'extra heat' is what the greenhouse effect is, right?

~ confused
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

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.
#56124 - 06/26/16 04:20 PM Re: Follow the photon! Is this right? [Re: samwik]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
I take it Paul doesn't believe in the greenhouse effect or global warming which doesn't surprise me as GOD is supposed to control things for him. I wouldn't waste my time trying to convince him it's pointless.

However as wrong and crazy as Paul may you can't fix Paul's issues up by making up your own equally bad answers, Samwik.

Let me give you the problem with your answer, yes the chance of the photon leaving Earth is increased but so is the chance of it being absorbed in the first place. If the probability of both processes is directly related to the atmospheric concentration then changing the concentration of C02 does nothing.

So for either heating or cooling to work in what you describe you require one of the processes to not change at the same rate. That is not how the greenhouse effect works.

In fact you can't bring any of the effect down to what is happening in a simple photon interaction. That is easy to prove because the ISS temperature in full sun is 149° C. That is the simple photon interaction of a body at the Earths distance from the sun. The sun side of the moon is similar temperature for exactly the same reason.

So the first problem both you and Paul need to discuss, is not what you talking about the stupid photon, but why isn't the sun side of Earth at 149° C.

Now we have the converse problem in the shadows. The ISS in the shadow of Earth and the dark side of the moon both drop to -184°C. So that's the second part of the problem why doesn't dark side of Earth (AKA night) drop to -184°C.

You can also easily calculate that if all the atmosphere was doing is averaging half the earth in light and half the dark side, the temperature of Earth would be -17°C. (the average of 149° C and -184°C).

Both start with that problem and leave the poor photon alone.


Edited by Orac (06/26/16 05:06 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#56129 - 06/28/16 09:51 PM Re: Follow the photon! Is this right? [Re: Orac]
samwik Offline
Megastar

Registered: 10/10/06
Posts: 1164
Loc: Colorado
Originally Posted By: Orac
Both start with that problem and leave the poor photon alone.
Orac, you want to “leave the poor photon alone” and avoid “an interesting and instructive lesson in physics?”
This must be a first!

Hopefully we all know why the moon and ISS, with no atmosphere, don’t experience a greenhouse effect,
and how albedo does affect their temperature. But maybe that would be a good new topic to start.

Please though could you explain what “answer” you are talking about,
when you say “…the problem with your answer …yes the chance of the photon leaving Earth is increased….”

What, from any of those postulated scenarios or descriptions,
leads you to see “the chance of the photon leaving Earth is increased”?
Sure, if two competing processes are balanced, then there won’t be any net effect.
Where do you see that balance, or any “chance …increased,” occurring here?
===

I thought Paul described (as I mentioned, “regardless of its validity”), an IR photon leaving the planet (one process),
or that photon being returned to the planet—being delayed, before leaving the planet—(a second process).
But both processes would not be equally or “directly related to the atmospheric concentration …of CO2” as you suggest.
Wouldn’t it be more like an unequal, inverse relationship?

But please feel free to clarify the above, or postulate some other scenario, where we might “follow the photon,”
and see if we can learn more about physics. Already, I think, we know that
it is not an “individual photon” that we are metaphorically following; but rather,
it’s the energy represented at various times, however it might be distributed and flow,
and from whence it came and to where it may go.

~ wink
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

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#56130 - 06/29/16 01:56 PM Re: Follow the photon! Is this right? [Re: samwik]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4136
Sam
Quote:

So, potentially, we have this IR photon bouncing back and forth between the ground and a CO2 molecule …potentially for hours on end
…before the IR photon might finally “miss” the CO2 molecule and head blissfully out into deep space. Right?


in the example process I posted I only used 1 co2 molecule and 1 photon to show that there
is zero energy gain that occurs in the atmosphere due to any interaction between the co2 molecule
and the photon.
I also show that by repeating the process there is no build up of energy
on the earths surface and that is what basic physics says about it ... Im simply repeating
what physics says will happen during photon absorbtion and emmition.

Quote:

Before the IR photon leaves the planet, especially while it is bouncing around down in the lower troposphere,
it will still function as heat if/when it hits a body or a thermometer. Won’t it?


think about a 1 dollar bill.
if you go to a store and buy something for 1 dollar then decide to get a refund
then you go to another store and do the same thing , and you repeat this over and
over and over ... you still have your 1 dollar even if you have went to a gazillion
stores and bought something and then gotten a refund as long as you get a refund from the last store that you visited.

and none of the gazillion stores have your dollar or any part of your dollar.

Quote:

Wouldn’t anyone expect that “adding more co2 molecules to the atmosphere” would provide more chances
for the IR photon to get intercepted, and bounce back and forth between ground and any other CO2 molecules,
before finally getting lucky enough to head out into deep space, thus finally helping to cool the planet?


thats the reason why I only used 1 photon and 1 co2 molecule.
if there is zero energy gain in the atmosphere with only 1 co2 molecule then
there is no way that adding more co2 molecules will show a gain either.

any energy gain that is possible in the atmosphere due to the 1 photon interaction
with the 1 co2 molecule should be seen in the 1 co2 molecule but it isnt seen.
and adding more photons or co2 molecules to complicate the issue will not add any
energy to the atmosphere nor will it add any energy to the earths surface
due to the infrared light bouncing back and forth between the earths surface
and the earths atmosphere.

from what I can tell the only energy that can be stored in this process is the energy
from sunlight that remains on the surface of the earth after the object emits the photon
of infrared light.

and that stored energy is due to energy from the ultra violet and visible light not energy from
the infrared light.

as for non co2 storage the below solar irradiance graph
shows that infrared radiation is stored in H20 mostly
in water vapor , clouds and in surface water etc ... the
graph does reference co2 absorbtion as tiny amounts.





but we dont want to complicate the issue because the focus is
on the possibilities of co2 being a molecule that is having
such a dramatic effect on our climate.

even though the co2 molecule possibly has the least
effect on the climate.

and of course co2 is the only molecule that taxes or fees or blocks can be sold or issued for profit in the carbon credit scam.

Quote:
Already, I think, we know that
it is not an “individual photon” that we are metaphorically following; but rather,
it’s the energy represented at various times, however it might be distributed and flow,
and from whence it came and to where it may go.


exactly!

but by following the photon we see where the energy
comes from and where the energy goes to.

and even if the energy flows to here or to there the
magnitude of the energy does not increase unless there
is some form of free energy developing in the process
somewhere.

so the title of the thread is correct.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#56131 - 06/29/16 03:27 PM Re: Follow the photon! Is this right? [Re: samwik]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: samwik
Hopefully we all know why the moon and ISS, with no atmosphere, don’t experience a greenhouse effect,
and how albedo does affect their temperature. But maybe that would be a good new topic to start.

Great you have worked out the the atmosphere is what is different. Now you need to establish what it does.

So now you have introduced a new concept albedo, and yep we need that one. So what is the difference in temperature if I paint the ISS white or black? That is the easiest way to look at that effect.

There is another effect you both haven't explained which is how is it the temperatures don't go to the extremes we see on the moon or the ISS. Our day/night temperatures are tiny compared to the normal swing you would expect. This is actually important in understanding what is happening as well.

Originally Posted By: samwik
When you say “…the problem with your answer …yes the chance of the photon leaving Earth is increased….”

What, from any of those postulated scenarios or descriptions,
leads you to see “the chance of the photon leaving Earth is increased”?

It's called probability smile

You have a non zero chance that any photon emitted in a random direction will be towards space. The more you "bounce your photon" the more chances there are for that photon to leave.

Lets do this with a dice, any time I roll my dice if I throw a six the photon goes out to space.

You now have the photon, quote "bouncing around" so lets say it bounced 3 times. You now throw the dice 3 times and any of those 3 throws that lands on a six means the photon went bye bye to space. See what happens to your photon if you start bouncing them around.

You might want to be very careful with bouncing photons around if you understand the above smile

Originally Posted By: samwik
But both processes would not be equally or “directly related to the atmospheric concentration …of CO2” as you suggest. Wouldn’t it be more like an unequal, inverse relationship?

Neither of you have actually got close to understanding what is happening because you seem lost playing ping pong with a photon. Lets give you a hint the back radiation is not the same IR photon that left earth and got absorbed by the CO2 molecule .... it's not a ping pong process you two seem to have turned it into.

Hint: IR bands like 7u an 15u will be very high in the back radiation but you will find very little 10u.


Edited by Orac (06/29/16 04:32 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#56132 - 06/29/16 04:32 PM Re: Follow the photon! Is this right? [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4136
Quote:
It's called probability


yes .. why dont you tell us what the probability will be
of a photon interacting with a co2 molecule in the atmosphere.

in fact give us a complete run down of the probability of the
processes involved but dont leave out the things of reality
such as the concentration of co2 , the inability of an excited
co2 molecule to absorb another photon of IR until it has emitted
an exact copy of the absorbed IR photon returning it to its previous energy level.

I believe we both would value your determination of the
probabilities involved and it will give you something to
do while sam and myself discuss the frivolous.

obviously you already know exactly how it should work.

so dont keep it a secret.
_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#56133 - 06/29/16 04:55 PM Re: Follow the photon! Is this right? [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
For a religious nutcase that is about the most intelligent statement made on the subject by you ... it almost makes sense except the whole probability bit went right over your head. The probability wasn't important it was something for SAM and his ping pong match.

There is one big error in your statement which I will fix, the CO2 molecule doesn't have to re-emit the photon, it can kinetically run into something else and change energy that way.

Remember ye old classic GOD physics where little gas molecules ran around colliding into each other and changing there energy.

For the record even a CO2 laser with a perfect setup does not obey 100% re-emission they make a lot of ... wait for it ... HEAT as the kinetic gas molecules smash into the glass. Almost all large CO2 lasers require a cooling jacket to deal with it.

So the CO2 molecule in the atmosphere may or may not re-emit the photon that is a case of wait for it .... probability.

Anyhow I will leave you two with it, I really have no intention of getting into ye old GOD physics with you in another stupid pointless discussion.


Edited by Orac (06/29/16 05:12 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#56134 - 06/29/16 05:31 PM Re: Follow the photon! Is this right? [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4136
Quote:
There is one big error in your statement which I will fix, the CO2 molecule doesn't have to re-emit the photon, it can kinetically run into something else and change energy that way.


we didnt have anything else up there for the co2 molecule to run into.

so it probably wouldnt run into anything that wasnt there and
it would eventually emit a photon.

I believe that is one of the things that sam wanted to discuss
later however so now I suppose that has been broken out
and you have already agreed to the kinetic transfer of energy
between molecules in the atmosphere.

still a kinetic energy transfer from one molecule to another
molecule only causes energy levels to change in the molecules
and does not cause heat to build up in the molecules or in the surrounding molecules in the atmosphere.

all of the transfered kinetic energy is used up in the energy
level changes.

else there is some form of energy being created or destroyed.

and the molecule that kinetic energy was transfered to will
immediately emit a photon of the same energy it received from
the kinetic energy transfer returning it to its previous energy level or it will collide with another molecule and once again a kinetic energy transfer will occur
etc ... etc ... etc ...

energy does not build up in the above process either.

so what we have in the example is that
the time interval where the re-emitted photon traveled
from the co2 molecule to the earths surface and was
absorbed by the object on the earth is removed and
replaced by the above process.

ie...
where before the introduction of another molecule into the example we had...

t=6
Earth E = 1
Atmos E = 0

we now have...

t=6
Earth E = .5
Atmos E = .5

as we started with 1 unit of energy in the 1 photon of
sunlight there is no change in the total energy.

in t=6 what has happened with the introduction of another
molecule for the co2 molecule to collide with and transfer
its energy into vs re-emitting a photon and sending the
photon back to the earths surface to warm the earths
surface has caused the energy of the earth to be reduced
or the earth to cool.

still theres no change in the total energy.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#56135 - 06/30/16 01:37 AM Re: Follow the photon! Is this right? [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
According to the above a gas can't get hot or cold the energy remains the same ... the gas is just a conduit for photons to bounce thru, that is literally what it says smile

So Paul the atmosphere is just a conduit then why doesn't the Earth behave like the moon and the ISS and go from -180 to 300 degrees C? You keep ignoring the fact the Earth is behaving differently to those close space bodies, which Samwik claimed was because of an atmosphere.

Your above statement says the energy should just bounce thru the atmosphere so why is the Earth different?

This goes back to my original post to you both, first identify what the atmosphere is doing and stop playing with bouncing photons.

Samwik correctly identified one thing called Albedo for the ISS and Moon. The bit he missed is for Earth that is two directional incoming and outgoing. Earth is an emitter of IR radiation and the atmosphere has an Albedo for that as well as incoming radiation from the sun.

So a key difference between Earth and the Moon/ISS is earth has two Albedo (one in and one out) for the atmosphere, something often missed by layman. Albedo is an overall average reflection coefficient of an object, the object in our case is the atmosphere, and we have two different but linked sources being Sun and Earth IR.

An easy way to deal with that would be to break the spectrum into bands and discuss the albedo and effects to both the sources. You might also discuss things that may change the Albedo of either direction.

So there we have one difference the atmosphere makes. Can you think of any others which might explain why Earth is reacting different to the Moon and ISS?

I am giving you a big hint there that "GreenHouse effect" is not a singular thing smile

For my part I have no intention of discussing the bouncing photon laugh


Edited by Orac (06/30/16 04:11 AM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#56141 - 06/30/16 11:45 AM Re: Follow the photon! Is this right? [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4136
orac

using the Moon and the ISS to attempt to describe the
earth is like comparing the earth to a large hollow tin can
and a solid ball of stone.

neither of which has its own internal heat like the earth does.

the ISS has to be supplied with heat and cooling.

and trying to heat the moon up by giving it an atmosphere
would be like trying to boil water for a cup of coffee
with a cigarette lighter outside in the wind during a
snowstorm at the north pole while standing on your head
and wondering why your doing this.


Quote:
According to the above a gas can't get hot or cold the energy remains the same


then explain how a gas gets hot or cold due to an interaction
between gas molecules.

if energy is conserved then how could any interaction
between gas molecules cause any heat without also having
caused a lower total energy in the gas molecules?

so if you know of a way to heat up or cool down gas
molecules by allowing them ( not forcing them ) to collide
with each other then I want to know how.

I have a propane cylinder that I recently filled and it
has a gazillion gas molecules in it and the gas molecules
in the container are all moving around inside the container
but when I touch the container its not hot its cold to the
touch.

you would think that I could heat my home with this container
of gas molecules without ever consuming any of the gas because
of all of the heat that is being ( CREATED ) due to the
gazillion collisions each nano second but thats not the case.

so why isnt the container heating up and heating up my house?

Quote:
the gas is just a conduit for photons to bounce thru, that is literally what it says


actually a photon never bounces , portions of photons are
always absorbed or reflected.

but I know what your saying.

and that is literally what photons are doing.

they are being absorbed and emitted , never causing a
gain or loss in total energy.

and if the absorption of a photon causes a collision with
other molecules and energy transfers occur between molecules
then there is still no gain or loss in the total energy.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#56143 - 06/30/16 02:23 PM Re: Follow the photon! Is this right? [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: paul
I have a propane cylinder that I recently filled and it has a gazillion gas molecules in it and the gas molecules in the container are all moving around inside the container but when I touch the container its not hot its cold to the touch.

you would think that I could heat my home with this container
of gas molecules without ever consuming any of the gas because
of all of the heat that is being ( CREATED ) due to the
gazillion collisions each nano second but thats not the case.

so why isnt the container heating up and heating up my house?

ROFL I do love Paul physics ..... try looking at how refrigeration or reverse cycle air conditioning works .. even putting your hand on the container while filling would have been funny laugh

Anyhow I am done with this rubbish please resume discussion with Samwik. I am definitely not touching this much Paul physics and there is too much work to bother dealing with. Ignore factor warp 10 engaged.


Edited by Orac (06/30/16 02:42 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#56144 - 06/30/16 02:51 PM Re: Follow the photon! Is this right? [Re: Orac]
samwik Offline
Megastar

Registered: 10/10/06
Posts: 1164
Loc: Colorado
Originally Posted By: Orac
...first identify what the atmosphere is doing and stop playing
with bouncing photons.
...
Samwik correctly identified one thing called Albedo for the ISS and Moon. The bit he missed is for Earth that is two directional incoming and outgoing.
...
For my part I have no intention of discussing the bouncing photon laugh
So much to say, to these insightful and remarkably coherent replies, yet so little time!

Thank you, Orac, for focusing on how the greenhouse-effect operates.
It is an important topic, which is why I’ve spent years posting information hoping to correct, or fill in, some of the many misguided misconceptions about the greenhouse effect that I often find being promoted, as if they were valid and complete, on the internet.

Back in late 2013, iirc, a report from NASA verified that CO2 has a cooling effect up in the stratosphere (which climate science already expected and predicted), and a few bloggers took that (perhaps as an excuse) to mean it wasn’t true that CO2 is a greenhouse gas. Anyway, some of that confused viewpoint, and rhetoric, turned up here at SAGG in 2014. With my old chemistry/biochemistry degrees, and having taken some university-level climate science classes fairly recently, in 2011 and 2014, I thought I should try helping where I could see obvious or common mistakes.
===

Several of these points, which you are trying to lead us to discover, have already been hashed out extensively.
For instance, you mention one point that I “…missed is for Earth that is two directional incoming and outgoing.”
There are many posts, such as those on Paul's thread, “Carbon Dioxide Trapping of Earth's Heat,” where I’ve endeavored to explain those specific points—the difference between the incoming and outgoing radiation—to Paul, regarding the greenhouse effect.

And ...I may have made some or many mistakes, or been unclear, myself in any of those posts where I try to explain the necessary details and/or nuances needed to fully understand, as Paul seeks to do—or thinks he has done—the true physical mechanisms that underlay the terminology and models used by the sciences.
....Or words to that effect. So please feel free to correct anything you might find.


I’ve also posted about, roughly, how as you said “IR bands like 7u an 15u will be very high in the back radiation but you will find very little 10u,”
when trying to explain to Paul about the difference between “atomic” absorption and “molecular” absorption of energy,
in Paul's thread, “NASA report verifies CO2 cools atmosphere.”
I’m fairly sure that this specific confusion, on Paul’s part, is why he thinks (erroneously)
that a molecule must always emit a photon of exactly the same energy as it absorbed.
===

In fact, that is why I thought this topic in the physics forum, where we try to follow a photon, would be helpful. It is clear from Paul’s post, quoted in the OP, as well as comments he’s made following up, that there are a few gap or oversimplifications or mix-ups, in his views related to radiative heat transfer, to say the least.

As I’ve repeated, even if Paul’s description is wrong, or “regardless of its validity” or lack of validity, I want to start with Paul’s description, and use his language,
to begin pinning down the misconceptions he operates under.
Then, with the fundamental root of the problem identified, my hope is to fill in the gaps, or correct the misunderstandings, so Paul can see
the science isn’t wrong or backwards, as he occasionally claims.
Originally Posted By: paul in August, 2014
bear with me , Im working on a anti green house effect.

global warmers want to count the heat each time it bounces back and fourth from the surface to the atmosphere , Im planning to counter that with run away cooling...

because its exactly backwards from what science says it will be , therefore it must be correct.

main line science makes a excellent backwards barometer.

It’s become apparent, in discussing the greenhouse effect with Paul on the climate-science forum, (as you may notice on this forum) that he doesn’t correctly or completely enough, understand the actual processes or mechanisms by which physical reality operates; and yet he uses his misconceptions as proof …to disprove the validity of the physical sciences needed to understand climate.

That is why I think it is still worth following a photon, even if we are starting out with a very unrealistic description. I expect to pick out certain points, which when corrected or fully explained or properly understood, will turn the hypothetical journey of a photon (or some energy) into a more realistic, as well as more fully informative and instructive, description.

For instance, the notion that, as Paul says,
"...at this point the object retains some of the heat energy
that it initially received from sunlight.
because the object released energy when it emitted the infrared light"
clearly indicate a confusion of some sort relating to how energy is absorbed, partitioned, or distributed.
That is also why his numbers, associated with the different steps, don't seem to make sense, istm, and need to be
questioned and more fully explained ...mańana.

~ wink
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

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#56145 - 06/30/16 11:28 PM Re: Follow the photon! Is this right? [Re: samwik]
paul Offline
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Registered: 03/21/06
Posts: 4136
Quote:
For instance, the notion that, as Paul says,
"...at this point the object retains some of the heat energy
that it initially received from sunlight.
because the object released energy when it emitted the infrared light"


oh I see it now , so the object (atom) that absorbed the photon
emitted a photon with the same energy.

yes , I was thinking along a broader base when I wrote that
part as in many photons that could
be absorbed or reflected by the object ... we should just
use a single atom on the earth instead of an entire object
... and we dont need an entire object anyway we only need a single atom to examine this because we only have 1 photon.

so you got me on that one.

this changes a lot though this means that when the atom on the earth emits the photon that is sent to the co2 molecule
the earth does not retain any of the energy.

because from what I understand when an atom absorbs a photon
it must emit a photon with the same energy in order to return
to its previous energy level.

so what we have now is

1 incoming photon from the sun.
1 atom on the earths surface.
1 co2 molecule in the atmosphere.

and thats all we have.

so

t=1
the photon is absorbed by the atom on the earth.

Earth E=1
Atmos E=0

t=2
the atom on the earth emits a IR photon.
Earth E=0
Atmos E=0

t=3
the co2 molecule absorbs the photon.
Earth E=0
Atmos E=1

t=4
the co2 molecule emits a IR photon
Earth E=0
Atmos E=0

t=5
the atom on the earth once again absorbs the photon.
Earth E=1
Atmos E=0

the process repeats and there is never any gain.

nothing stored.

unless the co2 molecule collides with another
molecule in the atmosphere.

in which case we have

t=6
the atom on the earth emits a IR photon.
Earth E=0
Atmos E=0

t=7
the c02 molecule absorbs the photon
Earth E=0
Atmos E=1

t=7
the c02 molecule collides with another molecule in the
atmosphere and a energy transfer occurs.
Earth E=0
Atmos E=1

if there are more co2 molecules in the atmosphere then
the odds of the co2 molecules colliding are greater
than if there are fewer co2 molecules in the atmosphere.

so lets let them collide with each other.
we add another co2 molecule.

time passes ............1 second

t=408
the c02 molecule collides with the other co2 molecule
400 times in 1 second (and thats being lenient)
and a energy transfer occurs each time.
Earth E=0
Atmos E=1

( only valid if a collision requires .0025 seconds)

Earth E=0
Atmos E=1

no change from t=7

and we had 2 co2 molecules !!

I understand the point of the greenhouse effect

in the above the energy stays in the atmosphere longer.

where it would normally have been sent away from the earth.

that makes sense , but that doesnt warm the planet.

note: unless there is energy being created and being
added as heat into the atmosphere by the co2 molecules
colliding then there is no added heat due to the collisions.

if that were possible then my propane tank would heat my
entire city.
because the gas in the tank is concentrated @ 1,000,000 ppm

we currently have 400 ppm in the atmosphere.

so lets say that the odds of a photon being absorbed by
a co2 molecule is 400 to 1,000,000

the same as saying the odds are 2500 to 1 that a photon will be absorbed by a co2 molecule.

and those odds are only valid if all of the co2 molecules are
spread out in a really super thin perfect sphere that surrounds the earth.

the odds increase as the sphere becomes thicker.

anyway.

what we need to examine now I suppose is this question.

will added co2 in the atmosphere cause or will it not cause
any warming of the earths surface?

so far all of the added energy is in the atmosphere.

also: would it stand to reason that having more particulate
matter in the atmosphere such as co2 would cause the earth
to recieve less sunlight?

I remember an experiment that shows that co2 traps heat.

here it is.



ooops wrong video...

well this one shows that air traps heat much better than co2

oh well that would be good evidence in the court when they
start prosecuting the climate deniers.


whats relevant about this video is that the bottle with the
co2 in it heats up much slower than the bottles with air
only in them ........ and that the bottle with
the co2 is cooling much faster and to a greater extent
than the bottles with only air in them.


but still this does not prove to me that co2 warms or cools
as the bottle disappears from view too many times in the
video.

can the climate deniers prosecute the climate believers?
given that we DO have evidence and they have had decades
and a few gazillion dollars yet they havent produced a
single tid bit of valid evidence to date that shows
any warming due to co2.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#56146 - 07/01/16 03:04 AM Re: Follow the photon! Is this right? [Re: paul]
samwik Offline
Megastar

Registered: 10/10/06
Posts: 1164
Loc: Colorado
Originally Posted By: paul
also: would it stand to reason that having more particulate
matter in the atmosphere such as co2 would cause the earth
to recieve less sunlight?
... cry Paul, in this one post of yours,
you've referred to CO2 as an atom, as a molecule, and finally as a particulate!
No, co2 won't "cause the earth to recieve less sunlight,"
because co2 is not a particulate.

CO2 is a molecule, so it will absorb a photon, rather than reflect or scatter a photon.
===


Originally Posted By: paul
I understand the point of the greenhouse effect
in the above the energy stays in the atmosphere longer.

where it would normally have been sent away from the earth.

that makes sense , but that doesnt warm the planet.
What?!? Why not?
Yes, it does warm the planet.
It is mostly the troposphere that is warmed when "the energy stays in the atmosphere longer,"
and some of that heat bounces back down to the surface of the planet. It is especially noticeable at night.

Your numbers don't add up. You have a total energy of one, in steps 1, 3, 5, and 7,
but total energy of zero for the even-numbered stages of your description.

I think your sequence needs more detail or nuance to show where the energy is going
...unless you want to be the one creating and destroying energy out of nowhere every other moment.


Originally Posted By: paul
note: unless there is energy being created and being
added as heat into the atmosphere by the co2 molecules
colliding then there is no added heat due to the collisions.

and those odds are only valid if all of the co2 molecules are
spread out in a really super thin perfect sphere that surrounds the earth.

the odds increase as the sphere becomes thicker.
...well I wasn't talking about heat transfer [not added (created?) heat] "due to the collisions"
...but I'm glad you can see how a sphere of co2 molecules could have an effect
...which would increase if the sphere got thicker.

...but if you're talking about "added heat due to the collisions" here, I hope you're not picturing collisions only occurring "horizontally" or side to side,
in that super-thin layer (up in the atmosphere?) somewhere.
I'm not sure why you think the sphere needs to be "super thin" and "perfect," but I suppose that is the simplest way to visualize or model the situation.

But whatever that layer is like, some of the extra heat bounces back down to the surface,
and it will warm anything on the surface of the planet,
or anywhere in between (the surface and your super-thin perfect sphere),
which absorbs that heat.



Originally Posted By: paul
what we need to examine now I suppose is this question.

will added co2 in the atmosphere cause or will it not cause
any warming of the earths surface?

so far all of the added energy is in the atmosphere.
...gee, I wonder if anybody has ever asked this question before. Maybe we could do some research and see if anybody has checked. confused

But please don't focus too much on the greenhouse effect. This is just about following a photon.

Originally Posted By: paul
...because from what I understand when an atom absorbs a photon
it must emit a photon with the same energy in order to return
to its previous energy level.
Okay, so here is a photon we can follow.

CO2 is a molecule, so when it absorbs a photon, it is not causing a single electron to jump up into a higher atomic orbital
...in the way you seem to be familiar with atoms doing.

It isn't the same process, which is why the photon re-emitted
from any molecule
doesn't need to be the same frequency as the original absorbed photon.

But I'd like to hear from an expert on the absorption of photons, by both atoms and molecules,
because I'm sure I've probably oversimplified too much too, or worse..... whistle

~
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

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#56147 - 07/01/16 04:29 AM Re: Follow the photon! Is this right? [Re: samwik]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
I understood what you were trying to do Samwik, and I could at least follow your argument, I could just see the simplification wouldn't work as I think you have now worked out.

The problem is that "greenhouse effect" is not a simple thing to understand and indeed the greenhouse effect on earth as a planet doesn't even work the same way as the greenhouse after which it is named. I would argue the name of the effect should actually should be changed which would help layman. It took months of arguing to get wikipedia to actually accept the analogy was faulty and the article still contains some errors.

As the process is very complicated and then you get the next problem you correctly identified in this quote
Originally Posted By: samwik
It’s become apparent, in discussing the greenhouse effect with Paul on the climate-science forum, (as you may notice on this forum) that he doesn’t correctly or completely enough, understand the actual processes or mechanisms by which physical reality operates; and yet he uses his misconceptions as proof …to disprove the validity of the physical sciences needed to understand climate.

That is true of every layman discussion I have ever seen on the subject, it's just the how out of depth that varies.

As you probably guessed my background is hard sciences and I care little about the result and politics, what I care about is that people don't butcher the physics.

The problem with the photon story is that a photon in the range of 4-100um has the mean free path of about 25 meters here at around sea level. You guys didn't even discuss and I suggest even know what that means. It basically mans an IR photon emitted off the earth as such won't make it 25m before it is absorbed by the atmosphere. Do you see the problem with the bouncing photon you are trying to tell me its going to climb up thru a couple of km of atmosphere 25 meters at a time. That isn't remotely what happens.

The story is the same as a garden hose or an electron in a wire you can't follow the movement of an individual electron or molecule of water.

A related question we sometimes get asked is how fast does an electron move thru a wire. That we we can answer and it's called drift velocity and it has simple mathematics.
http://resources.schoolscience.co.uk/cda/16plus/copelech2pg3.html

It's funny Layman imagine electrons flying thru wires at some incredible speed the reality is like in the worked example 5 amps in 0.5mm area cross section wire the electron moves at a slow tenth of a mm per second. The same situation exists for H2O molecule in a hose.

The movement of the IR energy thru the atmosphere looks much more like the hose or wire situation and I can always tell peoples understanding of the physics in how they discuss it. One of my concerns with climate scientists is many don't themselves understand the movement of the energy.

For example the roll of Nitrogen (which makes up 78% of the atmosphere as N2) is important. It shares a resonant frequency with CO2 and the two can easily kinetically exchange energy. The N2 can not emit the energy as a photon (its a Homonuclear molecule) and it stays in the N2 a long time ... hint it might move a fair way in that time in the atmosphere before it bumps into another CO2 molecule and gives the energy back.

There are in fact hundreds of these pathways and they do not all change the same with changing CO2 levels.

The reason the Earth doesn't rapidly change between -180 and 300 deg C is also telling you the energy isn't just transparently moving thru the atmosphere. The atmosphere itself must be holding onto some of the energy so it has the thermal equivalent of inertia. That is also obvious in that the temperature profile thru the height of the atmosphere.

The lesson here is the free mean path of an IR photon in the atmosphere is small and the photon bounce story thru the atmosphere as some fully transparent media is fanciful.


Edited by Orac (07/01/16 04:46 AM)
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I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#56148 - 07/01/16 05:03 AM Re: Follow the photon! Is this right? [Re: samwik]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: samwik
It isn't the same process, which is why the photon re-emitted from any molecule
doesn't need to be the same frequency as the original absorbed photon.

But I'd like to hear from an expert on the absorption of photons, by both atoms and molecules,
because I'm sure I've probably oversimplified too much too, or worse..... whistle

Yes you have gone to far and are now completely wrong. Paul is partially right but mostly wrong because he is ignoring the elephant in the room.

The CO2 molecule absorbs the IR photon and it goes to another stable state. You can't have a fractional state it won't be stable so the energy has to come back out reverting the state of the CO2 to any other stable state. So you can't get any different emission unless some interaction occurs that leaves our CO2 molecule in a new stable state.

Paul simplifies that to the CO2 reverts back to its original state and gives the photon back. Yes that can and does occur but the elephant in the room he won't talk about is that is but one of a pile (probably hundreds) of other things that can and do happen as well.

As I discussed above CO2 has a resonant frequency in common with Nitrogen in N2 form. They can easily transfer the energy in a kinetic energy exchange and in fact we use that to help pump CO2 laser tubes.

https://en.wikipedia.org/wiki/Carbon_dioxide_laser
Quote:
The population inversion in the laser is achieved by the following sequence: electron impact excites vibrational motion of the nitrogen. Because nitrogen is a homonuclear molecule, it cannot lose this energy by photon emission, and its excited vibrational levels are therefore metastable and live for a long time. Collisional energy transfer between the nitrogen and the carbon dioxide molecule causes vibrational excitation of the carbon dioxide, with sufficient efficiency to lead to the desired population inversion necessary for laser operation. The nitrogen molecules are left in a lower excited state.

The process occurs both direction but you can push the process by using the N2 by injecting electrons to pump the process in a controlled way.

Nitrogen (N2) makes up 78% of the atmosphere so you may want to ask how far a CO2 molecule is going to be able to go before it runs into an N2 molecule .. hint free mean path.

That are hundreds of other possible transfers and even some chemical reactions that can happen with a CO2 molecule which is ionized by our IR photon, all of which Paul just ignores. All he does is go for the one that returns the original photon.

N2 reacts in this frequency range with many gases as does CO2 and given the percentage of N2 in the atmosphere you might look at the frequencies involved and guess that the atmosphere is basically a transparent window at 10um and understand why as the nitrogen essentially transports that frequency thru. Outside the 10um range this process and N2 is not important at all. However given the percentage of N2 you might guess that is the one of the frequencies that would be very hard to block escaping the Earth as the N2 will effectively always carry it. The tricky bit is N2 doesn't absorb photons at that frequency (same as it can't emit them) and the energy exchange must be kinetic ... so you can't pick the behaviour by looking at a photon transmission graph which often throws layman and the odd climate scientist (its a non albedo effect but requires a catalyst/mediator which is the role the CO2 and other gases play .. N2 by itself would not act as such).

The fun frequencies to look at for climate change are 7um where water is king and 15um where both water and especially CO2 play a role. What you call global warming is actually what is happening pretty much solely in those two frequency (wavelength) ranges.

The above makes the point you need to look at the process on a frequency by frequency basis there is no generic case and it certainly isn't a bouncing photon.


Edited by Orac (07/01/16 06:17 AM)
_________________________
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#56149 - 07/01/16 01:25 PM Re: Follow the photon! Is this right? [Re: samwik]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4136
Sam

Quote:
you've referred to CO2 as an atom, as a molecule, and finally as a particulate!
No, co2 won't "cause the earth to recieve less sunlight,"
because co2 is not a particulate.


woops , I fudged that one , what I meant to say is would
the co2 in the atmosphere block the incoming sunlight.

and you say that co2 will not block the incoming sunlight.

in the below video a candle is being used to demonstrate that
co2 blocks IR light.

I have read that the only real difference between the light
from a candle and sunlight is the intensity of light.

now if co2 does not absorb incoming direct sunlight then please
tell me how the direct candle light in the below video
is being absorbed by the co2 in the tube.



at first in the above video there is nothing but air in the
tube and the IR camera is picking up the heat from the candle.

then when the co2 is introduced into the tube the image from
the IR camera somehow begins to dim and continues to dim until
there is no image of the candle being picked up by the IR
camera and displayed on the screen.

so according to the above video evidence co2 does in fact
block incoming direct sunlight.

this only shows that the IR light (infrared heat) is being blocked.

it does not say that all of the suns light is being blocked.

only the IR light (heat).

so from what I gather from this and the previous video is
that increased concentrations of co2 in the atmosphere
will cause the earth to cool.

Quote:
...but I'm glad you can see how a sphere of co2 molecules could have an effect
...which would increase if the sphere got thicker.


when I said thicker I was only referring to the volume of
space that the sphere occupied in other words the odds
would increase from 2500-1 to higher odds for instance
5000-1 making it less likely that a co2 molecule would
absorb a IR photon as it travels away from the earth.

making the sphere thicker would spread the co2 molecules
further apart from each other.

like taking a single sheet of notebook paper and vertically
distributing the atoms of that single sheet of paper inside
a area that has the same width and length but has a depth of
several miles.

while the sheet was intact the odds of tossing a photon
through the sheet of paper without having an interaction
between the photon and the sheet of paper would be zero.

yet when the atoms are vertically distributed the odds
increase greatly.

orac

I understand that there may be hundreds of interactions
that a photon traveling away from the earth can and most
likely will undergo but I could not use those interactions
in my simple example that sam and myself are discussing as
we were basically trying to figure out the interactions
between the single photon and the single co2 molecule.

but now that you have broke that out and placed it on
the table do you expect that even if the photon undergoes
the hundreds of interactions on its way to our single
co2 molecule in the atmosphere the single photon will
somehow no longer have the same frequency as it did when
it was first emitted by the object on the earth?

this may be where energy is being created or destroyed... laugh








_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#56151 - 07/01/16 02:26 PM Re: Follow the photon! Is this right? [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Paul I am not interested in discussing anything with you, it is simply too silly. Like your example of the video above ... stop and think .. lets give you why what you said is really really silly ... the camera above is AN INFRARED CAMERA it can't see normal visible light that is why the flame image looks funny on the screen.

https://en.wikipedia.org/wiki/Thermographic_camera

Get it the CO2 is absorbing the INFRARED light so the camera cant see the flame, nothing to do with visible light AKA sunlight .

Here is the hint if the CO2 absorbed VISIBLE LIGHT you wouldn't be able to see thru the cylinder ... DOH. You can still see the window in the background thru the cylinder when the flame image goes out. Here is the key frame image study it, the IR camera can't see thru the tube but you can see the window thru the tube AKA no visible light was harmed.

You can't see in the IR range which is why he needs the camera in the first place.

This is sort of why I can't deal with you I am sorry.



Edited by Orac (07/01/16 02:40 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#56152 - 07/01/16 02:39 PM Re: Follow the photon! Is this right? [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4136
Quote:
Get it the CO2 is absorbing the INFRARED light so the camera cant see the flame


exactly!! thank you.

https://en.wikipedia.org/wiki/Sunlight#Composition_and_power

Quote:
The Sun also emits X-rays, ultraviolet, visible light, infrared, and even radio waves;


so the sun emits infrared light and from the video we see
that co2 blocks infrared light.





_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#56153 - 07/01/16 02:41 PM Re: Follow the photon! Is this right? [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Did you also notice that the IR didn't re-emit like you claim it should? It also didn't absorb a fixed amount and then get saturated ... so where is the IR going?

I will give you a hint if he turned the camera to the side of the vessel you would see something interesting and I gave you the answer for a laser tube.

Your experiment image is exactly what I told you would happen.


Edited by Orac (07/01/16 02:47 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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