What explanation of the Greenhouse Effect do you use?

[Olde Europe]

Show me where I ever used the words "inputs" or "outputs" in regards to a closed system, idiot.

The Greenhouse Effect, stated simply is any closed system where more infrared energy is trapped than released artificially raising the mean temperature above what it would be otherwise unless a thermal equilibrium is reached. What determines the equilibrium point or whether it becomes thermal runaway is the fact that as heat increases, so does the rate of radiative escape, hopefully to some point where the elevated rate of escape finally equals the incoming energy. It is at that point the system stops heating.

 

[Olde Europe]

Odd that you don't think the atmosphere can absorb heat from the Sun yet you think it can be warmed by the Earth? Is it really that hard to understand that as Sunlight filters down from the Sun that it strikes dust particles and other particulates which are heated by the Sun and water droplets which are both heated by the Sun as well as acting like tiny spherical lenses to refract sunlight? Any wavelength which is transparent to a material like water passes through mostly, merely being changing in direction by an alteration of its speed of propagation through the medium as a function of its refractive index while the remaining energy acts to heat the substance. Of course, water droplets are not pure, full of contaminants and solids from the Earth, but as the wavelength becomes increasingly less transparent to the material it becomes increasingly more converted into infrared energy. The Sun puts out far more than just visible light.

Simply put: The earth's atmosphere is largely transparent to sunlight. That's why we don't live in permanent darkness on the surface, and we can catch a sunburn, too. The atmosphere is, however, largely opaque to the infrared radiation the earth's surface is emitting.

Greenhouse effect

Greenhouse gases effectively absorb thermal infrared radiation, emitted by the Earth’s surface, by the atmosphere itself due to the same gases, and by clouds. Atmospheric radiation is emitted to all sides, including downward to the Earth’s surface. Thus, greenhouse gases trap heat within the surface-troposphere system. This is called the greenhouse effect. Thermal infrared radiation in the troposphere is strongly coupled to the temperature of the atmosphere at the altitude at which it is emitted. In the troposphere, the temperature generally decreases with height. Effectively, infrared radiation emitted to space originates from an altitude with a temperature of, on average, –19°C, in balance with the net incoming solar radiation, whereas the Earth’s surface is kept at a much higher temperature of, on average, +14°C. An increase in the concentration of greenhouse gases leads to an increased infrared opacity of the atmosphere, and therefore to an effective radiation into space from a higher altitude at a lower temperature. This causes a radiative forcing that leads to an enhancement of the greenhouse effect, the so-called enhanced greenhouse effect.

Definition courtesy of IPCC AR4.

All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.​

 

[IanC]

The atmosphere serves as the MECHANISM by which the greenhouse takes effect. It first takes sunlight and converts it into IR radiation, then acts as an insulating layer to hold it in from escaping back out into space

The same guy who made this statement called me a 'tard.
And he wonders why people don't take him seriously.

This from a guy whose made NO qualification of any of his statements and has made nearly a dozen nonsensical statements of juvenile proportions now disputes that you need an atmosphere in order to have a greenhouse effect. Do you have any formal training in science at all?

I quoted you saying that solar insolation is converted to IR by the atmosphere. In fact the vast majority of solar input is absorbed by the surface and transformed there.

Did you actually mean what you said? I made sure it was quoted in context.

Unfortunately your supposed training has not taught you to think or write critically.

 

[IanC]

Odd that you don't think the atmosphere can absorb heat from the Sun yet you think it can be warmed by the Earth? Is it really that hard to understand that as Sunlight filters down from the Sun that it strikes dust particles and other particulates which are heated by the Sun and water droplets which are both heated by the Sun as well as acting like tiny spherical lenses to refract sunlight? Any wavelength which is transparent to a material like water passes through mostly, merely being changing in direction by an alteration of its speed of propagation through the medium as a function of its refractive index while the remaining energy acts to heat the substance. Of course, water droplets are not pure, full of contaminants and solids from the Earth, but as the wavelength becomes increasingly less transparent to the material it becomes increasingly more converted into infrared energy. The Sun puts out far more than just visible light.

Simply put: The earth's atmosphere is largely transparent to sunlight. That's why we don't live in permanent darkness on the surface, and we can catch a sunburn, too. The atmosphere is, however, largely opaque to the infrared radiation the earth's surface is emitting.

Greenhouse effect

Greenhouse gases effectively absorb thermal infrared radiation, emitted by the Earth’s surface, by the atmosphere itself due to the same gases, and by clouds. Atmospheric radiation is emitted to all sides, including downward to the Earth’s surface. Thus, greenhouse gases trap heat within the surface-troposphere system. This is called the greenhouse effect. Thermal infrared radiation in the troposphere is strongly coupled to the temperature of the atmosphere at the altitude at which it is emitted. In the troposphere, the temperature generally decreases with height. Effectively, infrared radiation emitted to space originates from an altitude with a temperature of, on average, –19°C, in balance with the net incoming solar radiation, whereas the Earth’s surface is kept at a much higher temperature of, on average, +14°C. An increase in the concentration of greenhouse gases leads to an increased infrared opacity of the atmosphere, and therefore to an effective radiation into space from a higher altitude at a lower temperature. This causes a radiative forcing that leads to an enhancement of the greenhouse effect, the so-called enhanced greenhouse effect.

Definition courtesy of IPCC AR4.

All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.​

Thanks.

Perhaps I expect too much. The atmosphere has an emissivity that is different for individual bands. I find it hard to simplify down to one height, one temperature.

To me the reason the GHE works is because the surface warms up to send more radiation through the Atmospheric Window which directly escapes to space because the atmospheric emissivity is close to zero for those bands.

 

[IanC]

The Enhanced GHE works by raising the emission height which means a lower temperature which in turn means less radiation produced to escape.

 

[Olde Europe]

To me the reason the GHE works is because the surface warms up to send more radiation through the Atmospheric Window which directly escapes to space because the atmospheric emissivity is close to zero for those bands.

Not sure I understand what you are saying here. Have you tried to say, "The reason why the GHE does not result in runaway heating is because the surface warms up to send more radiation through the Atmospheric Window." Is that it?

 

[IanC]

Odd that you don't think the atmosphere can absorb heat from the Sun yet you think it can be warmed by the Earth?

Here is a statement taken slightly out of context.

OE is correct that the atmosphere absorbs little of the solar insolation but does absorb a considerable fraction of surface emitted IR.

Tubesucker is more wrong than right when he focuses more on exceptions like particulates than the actual constituents.

 

[toobfreak]

• highly ordered high energy wavelength solar: What the hell is "highly ordered?" You mean circularly polarized? What? You mean phased? What is a high energy wavelength? How does frequency relate to energy? If there are any "higher energy" wavelengths, wouldn't they be the UV and SHORTER wavelengths rather than the lazy long IR wavelengths of heat? Now you are talking like you got your degree from the back of a box of Corn Flakes.
• diffuse longwave radiation: Again, are there some longwave radiation that isn't diffuse? And what makes it diffuse? Isn't blue light more diffuse in the fact that it is scattered by water droplets while IR passes through largely unchecked?
• Entropy? WTF?

Polarized? By what mechanism? By highly ordered I mean that it is collimated. The reason why you can focus sunlight with a magnifying glass.

High energy wavelength? We can tell the temperature of a distant star by the proportions of the radiation reaching us. A hotter star has the capability of producing higher energy photons than a cooler star. But the main clue is the amount produced at specific bands. Hot produces more radiation, at higher energy wavelengths on average.

Diffuse longwave? For wavelengths directly escaping through the Atmospheric Window the radiation is somewhat ordered because the photons only travel in a direct line away from the surface. Radiation absorbed and emitted by GHGs is totally scattered in all directions.

Entropy is a fairly difficult concept. If we are having problems coming to agreement on simple concepts it would be a waste of time to skip ahead several levels.

Alright. Let's take a look at what crap is being spewed by this shithead. Another USMB shithead who questions and refutes everyone else's qualifications and education while in usual Tard fashion, refuses to give us the slightest detail of his own. Yet somehow we are supposed to take him seriously?

Funny, anywhere else, you tell someone you are a CPA, chemist, doctor, etc., and people accept that on the face of it. Only here do people talk at length about all manner of subject with no qualification as to their background or experience in the matter and those that do state some qualification get soundly dismissed! So we have those that never state any qualifications at all and those that do in the second group being dismissed by the first!

Anywhere else, in talking about economics, a person stating they are an economist is listened to, in discussing education, a person stating they are a teacher is believed, in talking about automobiles, a person giving advice stating he works as a car mechanic is listened to. I've found that people who refuse to discuss themselves do so because they operate from a vulnerable position they wish to hide, especially when they attack and criticize others for no reason then question THEIR qualification! Here is this "IanC" ass whose been on this board for ten years yet this is the first time I've seen him post? A man of few posts and even fewer likes comes on here making nonsensical statement after another while attacking others who are aboveboard.

AS the famous Albert Osborn once said, THOSE WHO EXPOSE THEIR UNDEVELOPED NATURES WOULD OF COURSE NOT DO IT IF THEY KNEW THEY WERE DOING IT. THE TRAGEDY OF IGNORANCE IS IGNORANCE OF IT. And here we have IanC painting himself an ignorant fool by merely allowing himself to paint himself into a corner of his own doing.

Let's lumber through IanC's statements step by step:

• By highly ordered I mean that it is collimated. The reason why you can focus sunlight with a magnifying glass. In nearly a lifetime of study of light, optics, stars, etc., I've never heard sunlight referred to as being "collimated" -------- until NOW. "Highly ordered." A totally vague description which could mean anything. Is sunlight collimated? No. Anything collimated is understood to be put into alignment. Sunlight leaves the solar surface radiating outward as a spherical wavefront. The Sun is no more collimated than any other radiative body. It arrives at the Earth sensibly parallel only because of the great distance it has traveled resulting in the fact that we are sampling so small a surface area of its spherical front that any given portion appears to us as planar. A lens would focus sunlight in any regard being a converging (biconvex) lens, perhaps to a different focus unless the light was wholly diffuse, making IanC's claim that sunlight is "highly ordered," or collimated, nonsensical, or as they say on the street: HORSESHIT. No one with any real sense or understanding of light or optics would refer to sunlight in this way unless they were just trying to pass on sophisticated sounding jargon hoping to impress. Try searching for the term: Collimated Sunlight and see what you get. Conclusion: BUSTED.
• High energy wavelength? We can tell the temperature of a distant star by the proportions of the radiation reaching us. A hotter star has the capability of producing higher energy photons than a cooler star. But the main clue is the amount produced at specific bands. Hot produces more radiation, at higher energy wavelengths on average. "High energy wavelength," a clumsy terminology. High energy refers to short wavelengths, x-rays, gamma rays, etc. Wavelength is normally referred to by it's length not by its energy, which here is totally open to asking what constitutes "high energy" in IanC's mind? For all intents and purposes, I can only assume he was intending to refer to blue light and UV light, the SHORTER end of the Sun's primary spectrum. As for the bit about judging stellar temperature, it is not done by the "proportions of the radiation," producing higher energy," etc., it is done by simple spectral analysis of the star's color spectrum in what is referred to as its spectral and luminosity classification, according to Hertzsprung-Russel, along the main sequence typically known as OBAFGKM, with a type O star being the hottest and bluest. This is a function of the star's apparent blackbody radiation. The DEGREE of radiation (intrinsic brightness) we cannot know directly, a stars distance must be inferred by parallax or other means (t tauri stars etc.). Not sure how any of this relates to our thread topic here, but once again, IanC shows himself to be rather cavalier in his jargon as if he were talking down to us trying to make it simple enough to understand when in reality it simply sounds like he has a far less than perfect understanding himself. For what it's worth, the Sun is a yellow dwarf, a type G3 star if I remember right. The reason why our eyes are keyed to be most sensitive to around 550 nm wavelength, the yellow-green, or put another way, the color of grass and most stuff growing around us. Conclusion: BUSTED. IanC sounds like he is just trying to repeat stuff he barely understands himself.
• Diffuse longwave? For wavelengths directly escaping through the Atmospheric Window the radiation is somewhat ordered because the photons only travel in a direct line away from the surface. Radiation absorbed and emitted by GHGs is totally scattered in all directions. Eeya. I'll skip over the reference to "diffuse longwave" because again, it is so vague a term as to again sound like empty jargon. I can only assume he was trying to say scattered IR light. Generally, all IR is scattered. "Atmospheric Window," another jargon phrase sounding like a "tech-speak" term hoping to impress presumed to be an attempt to refer to that percentage of energy re-radiated back out into space. BTW, all light travels in a straight line unless acted upon by an outside force (intense gravitational warping of the space it is in, going through some refractive medium like air, glass, etc). It should be noted that even in warped time-space, light is still traveling in a straight line, relative to the space it is in. As to radiation being "somewhat ordered" because photons only travel in a straight line away from the surface," again, HORSESHIT, radiation traveling in a straight line away from the Earth's surface means it is traveling in all directions outward spherically, the exact OPPOSITE of what he initially claimed, not unlike the GHG radiations going in all directions he refers to as scattered in his very next sentence! And unless you can show me a study done where they measured Earth energy radiating into space from out in space by a probe to determine that it all radiate at a right angle to the Earth's surface (directly away and not at some random angles), I must call BULLSHIT to this claim as well. Conclusion: BUSTED. More techno-jargon half-baked crap spoken by some clown who read a few articles or books on a subject and now thinks himself an expert.
• Entropy is a fairly difficult concept. If we are having problems coming to agreement on simple concepts it would be a waste of time to skip ahead several levels. Ahha. I was studying entropy as a schoolboy. Entropy of matter is a rather big question in cosmology in deciding the ultimate fate and timescale of the universe. In the context of this discussion, it is assumed to mean the gradual decay of energy and/or order in an ordered system to a state of total DIS-order and total unpredictability (statistical or otherwise). Was this the "fairly difficult concept" that was just too far over our heads to verbalize, son?

Conclusions: If IanC knows anything at all about climate, atmospherics, gases, light, etc., it would seem to be that of an amateur on a grade school level. If you tell me you actually work in the field, it would not bode well for the general "science." Mind you, I do not even claim to be an expert at all on climate, climate change, etc., though I have studied weather extensively along with the aforementioned general physics and optical science, but I'm no dummy, I have yet to read or hear any model of why we should think the Earth is coming to a disastrous end of irreconcilable changes due simply to a few years of industrial production in lieu of what the Earth routinely deals with that ever meets the common sense test, and anyone I've ever discussed the matter with or listened to, the more caught up they are in it the more they seem bent on just selling me an unprovable model which very imperfectly represents the Earth.

Climate is always changing, always has been, and every factor touted as being responsible by man has been present to a far greater degree before without us. If the Earth warms a little, if some of the ice melts, if the oceans rise a few cm, they have before and they will do so again, with or without us. What amazes me is how mankind has built all this stuff right along the water's edge with NO THOUGHT or planning or apparent consideration that shit goes up and down! Now we are shitting ourselves because the sea has risen a few centimeters? It's another century before mankind can dare call himself "green" and you cannot force it. For now, if you want to cut production of agents to reduce GHG particulates, you need to slowly reduce human population, simple as that. ITMT, the Earth will adjust as it always does, the question is, can mankind?

 

[Wuwei]

Wow that is the most verbose diatribe I have ever seen at USMB.

 

[toobfreak]

The atmosphere serves as the MECHANISM by which the greenhouse takes effect. It first takes sunlight and converts it into IR radiation, then acts as an insulating layer to hold it in from escaping back out into space

The same guy who made this statement called me a 'tard.

And he wonders why people don't take him seriously.

Serious question, Ian: Why on earth don't you help him to clean up that statement? That way we all might learn something about the issue, and arrive at something like a clearer depiction of what the GHE really is. For, as of now, all we learned was about your ability to heap contempt on others.

Yes, it isn't the atmosphere that "converts" sunlight into IR radiation. Simply put, it's the surface that absorbs sunlight, warms up, and emits IR radiation, which is then absorbed by the GHGs in the atmosphere.

Odd that you don't think the atmosphere can absorb heat from the Sun yet you think it can be warmed by the Earth? Is it really that hard to understand that as Sunlight filters down from the Sun that it strikes dust particles and other particulates which are heated by the Sun and water droplets which are both heated by the Sun as well as acting like tiny spherical lenses to refract sunlight? Any wavelength which is transparent to a material like water passes through mostly, merely being changing in direction by an alteration of its speed of propagation through the medium as a function of its refractive index while the remaining energy acts to heat the substance. Of course, water droplets are not pure, full of contaminants and solids from the Earth, but as the wavelength becomes increasingly less transparent to the material it becomes increasingly more converted into infrared energy. The Sun puts out far more than just visible light.

I meant to add this diagram before but got caught up in writing another post. For all the asshats like cnm and IanC who have a problem understanding that our atmosphere CONVERTS solar energy to infrared, here is a diagram:

The atmosphere blocks a full 30% of the direct incoming solar flux with a full 18% of that ABSORBED. HOW is it absorbed? It can only be absorbed as heat energy (converted to IR), thereby raising the energy state of the ensuing matter (raising valence electron energy to a higher level). All those who scoffed at this are hereby busted again as just more climatology asshats with no real understanding of physics. BTW, if you want the source or more info to read on sunlight, greenhouse effect and related topics, you can do so here:

www.eng.uc.edu/~beaucag/Classes/SolarPowerForAfrica/BookPartsPVTechnical/Sunlight_01.pdf

 

[jc456]

well a greenhouse is a house with glass. it's effect is to cause plants to grow. Plants grow all over the globe. moisture and warmth with sun do quite a lot. The arctic and antarctic don't work cause you can't get to soil, and instead you get the reverse, snow and ice. don't recall snow and ice in a greenhouse.

 

[toobfreak]

Wow that is the most verbose diatribe I have ever seen at USMB.

TRANSLATION: You can't dispute the material so again, attack the messenger. Probably more substance in my one post there than all 3,400 of yours.

 

[jc456]

Wow. It didn't take long for this thread to be hijacked from GHE explanations to arctic ice.

how can you have arctic ice if you have a greenhouse effect? so when you go to a greenhouse with plants, there's ice in the building? hmmmm show me where

 

[jc456]

Wow. It didn't take long for this thread to be hijacked from GHE explanations to arctic ice.

I should have made it more clear. There is a dearth of decent explanations for the GHE.

I have my own understanding of it but I would be hard pressed to pass it along to a layman because the literature is so poor.

I was hoping someone else had stumbled onto a good site.

funny, cause no one can actually find a greenhouse effect cause there is actual ice on two ends of the globe. how can you say greenhouse and ice in the same sentence other than making a point?

 

[Wuwei]

I meant to add this diagram

Look up Trenberth Diagram. for a more complete picture that I think is "sanctioned" by the IPCC. However some of the deniers here scoff at Trenberth.

...raising valence electron energy to a higher level...

That is not part of the greenhouse effect. That happens with shorter wave energy, but cannot happen with thermal radiation from the earth. The valence states are unaffected. It's the vibration states of triatomic molecules that can absorb radiation given by the LWIR from the earth. It is that energy range that is important in the GHE. ( Molecules with more than 3 elements also have vibration modes.)

.

 

[Olde Europe]

The atmosphere blocks a full 30% of the direct incoming solar flux with a full 18% of that ABSORBED. HOW is it absorbed? It can only be absorbed as heat energy (converted to IR), thereby raising the energy state of the ensuing matter (raising valence electron energy to a higher level). All those who scoffed at this are hereby busted again as just more climatology asshats with no real understanding of physics.

It may surprise you to learn that, but everyone posting on here (as far as I can see them) knows that.

Those 18% compare to the 77% of sunlight warming the surface PLUS another roughly 100% of back radiation doing the same, how?

Which is why we say, sunlight largely warms the surface, which radiates infrared, which in turn warms up GHGs, which radiates back to warm the surface more (compared to a non-GHG scenario). That doesn't mean the sun doesn't warm the atmosphere directly, just that it's a small part of the overall energy flux.

See:

 

[Sunsettommy]

I meant to add this diagram

Look up Trenberth Diagram. for a more complete picture that I think is "sanctioned" by the IPCC. However some of the deniers here scoff at Trenberth.

...raising valence electron energy to a higher level...

That is not part of the greenhouse effect. That happens with shorter wave energy, but cannot happen with thermal radiation from the earth. The valence states are unaffected. It's the vibration states of triatomic molecules that can absorb radiation given by the LWIR from the earth. It is that energy range that is important in the GHE. ( Molecules with more than 3 elements also have vibration modes.)

.

It can be applied to ANY atom that absorbs energy, as shown here:

Electron Configuration and Valence Electrons

"The outermost orbital shell of an atom is called its valence shell, and the electrons in the valence shell are valence electrons. Valence electrons are the highest energy electrons in an atom and are therefore the most reactive. While inner electrons (those not in the valence shell) typically don't participate in chemical bonding and reactions, valence electrons can be gained, lost, or shared to form chemical bonds. For this reason, elements with the same number of valence electrons tend to have similar chemical properties, since they tend to gain, lose, or share valence electrons in the same way. The Periodic Table was designed with this feature in mind. Each element has a number of valence electrons equal to its group number on the Periodic Table."

===========================================================================
I knew about this from High School Chemistry class, around 1978.

 

[toobfreak]

I meant to add this diagram

Look up Trenberth Diagram. for a more complete picture that I think is "sanctioned" by the IPCC. However some of the deniers here scoff at Trenberth.

Simple enough model. Unprovable. Obviously a source for a lot of the internalized climatological jargon I see thrown around here.

...raising valence electron energy to a higher level...

That is not part of the greenhouse effect. That happens with shorter wave energy, but cannot happen with thermal radiation from the earth. The valence states are unaffected. It's the vibration states of triatomic molecules that can absorb radiation given by the LWIR from the earth. It is that energy range that is important in the GHE. ( Molecules with more than 3 elements also have vibration modes.).

Be clear that I did not say that any electrons were risen to the next stable energy shell or forced to leave the atom. Any material heated is absorbed energy in the form of greater vibrational energy in the electron cloud, triatomic or otherwise.

 

[Wuwei]

Wow that is the most verbose diatribe I have ever seen at USMB.

TRANSLATION: You can't dispute the material so again, attack the messenger. Probably more substance in my one post there than all 3,400 of yours.

Wow that is the most verbose diatribe I have ever seen at USMB.

What I meant by that is your unnecessary and lengthy references to the Hertzsprung Russell diagram and general relativity, etc. etc.


.

 

[Sunsettommy]

The atmosphere blocks a full 30% of the direct incoming solar flux with a full 18% of that ABSORBED. HOW is it absorbed? It can only be absorbed as heat energy (converted to IR), thereby raising the energy state of the ensuing matter (raising valence electron energy to a higher level). All those who scoffed at this are hereby busted again as just more climatology asshats with no real understanding of physics.

It may surprise you to learn that, but everyone posting on here (as far as I can see them) knows that.

Those 18% compare to the 77% of sunlight warming the surface PLUS another roughly 100% of back radiation doing the same, how?

Which is why we say, sunlight largely warms the surface, which radiates infrared, which in turn warms up GHGs, which radiates back to warm the surface more (compared to a non-GHG scenario). That doesn't mean the sun doesn't warm the atmosphere directly, just that it's a small part of the overall energy flux.

See:

"which radiates back to warm the surface more..."

This incorrect since that specific energy flow first LEFT the surface to be absorbed again then radiated back down, thereby NO additional increase in warming happened. You can't create energy out of nothing.