In previous remarks on the HOME page, I've quoted authorities, such as Prof. Reid Bryson, and well-known history, such as the Norse settlement of Greenland and Vinland, to assure you that the global warming "crisis" is exaggerated. Serious scientists, such as Prof. Bryson (and others on the references page) tell us so; the recorded history of Western civilization (and other civilizations) tell us so as well. Many of those scientists and historians point to other likely causes of global climate change (both warming and cooling). You can find a discussion of what really controls the climate
here
This page explains the science behind "greenhouse warming". As you'll see, "greenhouse warming" is very limited, for several reasons.
The fundamental fallacy in the man-made global warming hoax is the claim that carbon dioxide (CO2) is an important greenhouse gas. It isn't, for several reasons. I'm going to explain the reasons, qualitatively, and then give you some quantitative numbers that show how unimportant CO2 is.
Reason #1: A greenhouse can get only so warm...
Most people don't understand how a GHG works. It doesn't PREVENT infrared (IR) photons from escaping, it just slows them down, by absorbing them and re-emitting them. The re-emission is into all directions. The photons emitted downward haven't cooled the earth at all; the ones emitted upward have a chance to escape to space (= cooling) or to be absorbed by another GHG molecule, where the process is repeated. Eventually the IR photons escape, but the Sun returns before they all can, and warming begins again. (In the Arctic and Antarctic Winter, of course, the Sun doesn't return very soon, IR photons continue to escape, and it gets very cold.)
A blanket on your bed slows the escape of air warmed by your body (and replacement by cooler air). Adding more GHG to our atmosphere doesn't guarantee continued warming, anymore than adding a fifth blanket on the bed will make you warmer than the fourth blanket. The upper limit is 98.6 F; once you're there, you won't get any warmer. Once you have enough GHG to intercept all the infrared photons, adding more GHG has no effect. Over most of the earth, this is true. Because of H2O (not CO2), the greenhouse effect is maxed out.
Mathematically, GHG's obey a logarithmic law. Like adding multiple blankets to the bed, each successive increment of GHG has only half the warming effect of the previous increment. That's because the newly-added molecules of GHG have to compete with the ones already there - both H2O and CO2. If dx of GHG causes dT of warming,
then all the GHG that can be added (an infinite series of dx's)
causes warming of dT + dT/2 + dT/4 + dT/8 + dT/16 + dT/32 + ....... = 2 dT.
If we assume (for argument) that all the warming in the 20th Century (1 F) was caused by GHG, the maximum additional heating to be caused by all future GHG is another 1 F. BTW, world temperature during the Medieval Warm Period was more than 2 F warmer than now.
Eventually the atmosphere (at a particular wavelength) becomes opaque; no infrared photons can escape. Additional GHG has no effect beyond that point. In the real atmosphere, CO2 added by humans has to compete with much more natural CO2 and vastly more H2O. It just doesn't make any difference across most of the spectrum.
Reason #2: CO2 is not an important absorber.......
We need to remember that molecules (H2O, CO2) have resonant frequencies (wavelengths); the tri-atomic molecules,
depending on their geometry, may absorb infrared radiant energy by vibrating and by rotating. Take a look at the sketch on the right, a representation of the two major greenhouse gasses, H2O and CO2. Notice H2O is asymmetrical, and slightly polarized. That is, the hydrogen (H) end of the molecule tends to be slightly positive, and the oxygen (O) end slightly negative. An electromagnetic (E-M) wave, alternating between positive and negative, causes the H2O molecule to rotate, and absorb anergy. In addition, electromagnetic waves of a resonant frequency cause the H-O bonds to resonate, to vibrate. Both vibration and rotation absorb energy from the E-M wave.
Now look at the CO2 molecule (O-C-O). It's symmetrical and unpolarized, so it doesn't rotate when an E-M wave passes by. It has only one vibrational mode, along the O-C-O axis. It's a much less efficient absorber of E-M energy than H2O, and that's what the greenhouse effect is all about.
Because of its single (vibrational) resonance, CO2 has only a few absorption lines in Earth's infrared spectrum, around 2.5, 3.5, and 14.8 micrometers (um). What kind of infrared photons does a CO2 molecule "catch" at these wavelengths? At 14.8 um, they come from an object whose temperature is about 200 degrees K - about 100 degrees F below zero. Nothing on earth is really that cold, but everything emits radiant energy photons across the infrared spectrum. There just aren't many of them emitted at 14.8 um, and they carry very, very little energy. Capturing them does very little to keep Earth warm, like a blanket that covers only a small part of your body. 
Likewise, photons at 3.5 um wavelength correspond to a temperature of 828 degreees K. Terribly hot, but nothing on Earth's surface, except the inside of a volcano, or a forest fire, is like that. This is also an insignificant source of photons for the greenhouse effect.
The figure on the left illustrates the broad spectrum of absorption (top) by the H2O molecule - across the emission spectrum of the earth and lower atmosphere - in comparison with the narrow spectrum (bottom) of CO2. CO2 just doesn't catch most of the infrared energy leaving the earth - effectively, it isn't there.
Reason #3: There's very little CO2 around.......
Another reason global warming by CO2 is unimportant is because there's very little of it - 388 parts per million by volume (ppmv). That's less than 0.04 % of the atmosphere. Water vapor, on the other hand, ranges up to 4% - 100 times as much.
The real reason man-made global warming is unimportant is because natural CO2 is more than 96% of all the CO2 in the atmosphere. Even if CO2 were an important infrared absorber (as it isn't), complete elimination of all human CO2 emission would have no practical effect. Suppose we were to cut all human CO2 emission by 25% (which would cripple our economy). That would be 1% of all the CO2 in the atmosphere. Changing anything by 1% is unlikely to lead to catastrophe.
And, of course, the major emitter of CO2 is China - which is opening a new coal-fired electricity generating plant every week, and will do so for the next 15 years. They understand the science, and have no intention of restricting their CO2-based economy. India and Brazil are following the same path. But the UN - and Obama, Ritter, Udall, Bennett, Pelosi, Clinton, and our other politicians - want the US to reduce our CO2 emissions 80% by 2050. Just us. Just you. These are the politicians who just passed a "stimulus bill" - mostly pork - that will cost you, your children, and your grandchildren, trillions. A reduction of 80% in CO2 emissions means:
- The CO2 emissions level of the United States in 1910.
- A per capita CO2 emissions level as in 1875 (there will be more of us in 2050).
Incidentally, greenhouse gases lead to warming, not cooling. I hope that's obvious from the discussion above, but as "global warming" becomes less and less credible, the alarmists are beginning to claim the crisis is "climate change" - including cooling.
Another major agent of climate change - much more important than CO2 - is cloud cover. We all have experience of that; we know how a cloudy sky cools a hot Summer day, and how clouds warm a Winter night. In radiative terms, clouds are black bodies - objects which absorb all the infrared photons they receive. This is true across the IR spectrum; they're much better than gaseous H2O and CO2 in their "greenhouse effect." In daylight, they scatter sunlight back, away from Earth. So what is their net effect? Cooling? Warming? Nobody knows. Whatever it is, it's more important than CO2, and it's not controllable by humanity. Another fatal flaw in controlling the "climate crisis."
Did you get all that?
- CO2 is a weak absorber, much less important than water vapor and clouds,
- temperature DOESN'T continue to increase with added greenhouse gas,
- the vast majority of CO2 in the atmosphere is natural (and far less than it has been in the past),
- and foreigners - China, India, Brazil - are too smart to believe the "climate crisis" fraud.
Those are the qualitative explanations of the unimportant greenhouse warming due to CO2. Let's now look at some numbers describing the magnitude of CO2's greenhouse effect. The numbers come from the IPCC's Fourth Assessment Report, Working Group 1. This document can be downloaded from the University Corporation for Atmospheric Research, at
Working Group 1 Working Group 1 contains the scientific rationale and data on which other parts of the IPCC report are based.
In AR4WG1_Pubs_FAQs, FAQ 1.1, Figure 1, you'll find a diagram of the solar energy that warms our planet's surface (168 watts/sq meter) and atmosphere (67 w/sq m), totalling 235 w/sq m. If the earth is not to warm or cool on a long term basis, that incoming solar energy must be balanced by outgoing energy in the longwave infrared (5 - 15 micrometers) spectrum. As may be seen on the right in the diagram, 235 w/sq m eventually escapes.
Of particular interest are the two energy exchanges in the lower right of the figure, 390 w/sq m radiated (up) from the surface, and 324 w/sq m radiated down from the atmosphere. This 324 w/sq m is the "greenhouse effect"; it's the radiant energy the atmosphere captures and returns to the surface, like a second sun in the sky. Fortunately, this "sun" shines even during the night. The greenhouse radiant energy warms the earth by about 33 degrees C, or 60 F. Without it, the earth would be uninhabitable. How much of this beneficial greenhouse effect is due to water vapor, and how much is due to carbon dioxide? A later table in the IPCC report tells us (though they try to hide the values).
In AR4WG1_Pubs_FAQs, you'll find FAQ 2.1, figure 2. This figure itemizes the anthropogenic greenhouse gasses
that contribute to global warming. The total radiative forcing from carbon dioxide and all other anthropogenic gasses is only 1.6 watts/ square meter. That's out of the total of 324 w/sq m due to the total greenhouse effect. The rest - i.e., 322 w/sq m - comes from natural greenhouse gasses, which don't appear on Figure 2. If they did, any casual reader would immediately recognize how natural water vapor and natural carbon dioxide dominate the greenhouse effect.
In case you're wondering how many degrees C or F these "radiative forcings" amount to, the 324 w/sq m from the atmosphere warms the earth by 33 C, so it's about a 10:1 ratio (9.81818...) of w/sq m to degrees C. So the 1.6 w/sq m of radiative forcing due to all man-made greenhouse gasses causes a warming of 0.16 C or 0.29 F.
Yes, that's what this "global warming crisis" is all about. All the carbon dioxide and other industrial greenhouse gasses added to the atmosphere have warmed the earth by a third of a Fahrenheit degree.
Incidentally, the cartoon above, of incoming and outgoing energy, is by Dr. Kevin Trenberth of NCAR; it was done for an IPCC report. Dr. Trenberth is quoted in the "ClimateGate" emails as saying:
"We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!" The numbers you see in the figure, according to Trenberth - don't work out. But that's the basis of the claims of a crisis of climate, due to CO2.
So if CO2 doesn't control Earth's climate, what does? In the long term (tens of thousands of years), it's our current location of continents, resulting from Continental Drift. In the short term (decades and centuries), it's solar and ocean variability.
Man, you wimpy Americans are nothing like us Norsemen. I'm kind of ashamed of you - since, in a sense, I 
was the First American. We Norse found this continent a thousand years ago. Now you're letting Socialist politicians - like the ones I left behind in Europe - take it away from you. Lucky Leif
Home
Rev. Mar 2009
Reason #1: A greenhouse can get only so warm...
Most people don't understand how a GHG works. It doesn't PREVENT infrared (IR) photons from escaping, it just slows them down, by absorbing them and re-emitting them. The re-emission is into all directions. The photons emitted downward haven't cooled the earth at all; the ones emitted upward have a chance to escape to space (= cooling) or to be absorbed by another GHG molecule, where the process is repeated. Eventually the IR photons escape, but the Sun returns before they all can, and warming begins again. (In the Arctic and Antarctic Winter, of course, the Sun doesn't return very soon, IR photons continue to escape, and it gets very cold.)
A blanket on your bed slows the escape of air warmed by your body (and replacement by cooler air). Adding more GHG to our atmosphere doesn't guarantee continued warming, anymore than adding a fifth blanket on the bed will make you warmer than the fourth blanket. The upper limit is 98.6 F; once you're there, you won't get any warmer. Once you have enough GHG to intercept all the infrared photons, adding more GHG has no effect. Over most of the earth, this is true. Because of H2O (not CO2), the greenhouse effect is maxed out.
Mathematically, GHG's obey a logarithmic law. Like adding multiple blankets to the bed, each successive increment of GHG has only half the warming effect of the previous increment. That's because the newly-added molecules of GHG have to compete with the ones already there - both H2O and CO2. If dx of GHG causes dT of warming,
then all the GHG that can be added (an infinite series of dx's)
causes warming of dT + dT/2 + dT/4 + dT/8 + dT/16 + dT/32 + ....... = 2 dT.
If we assume (for argument) that all the warming in the 20th Century (1 F) was caused by GHG, the maximum additional heating to be caused by all future GHG is another 1 F. BTW, world temperature during the Medieval Warm Period was more than 2 F warmer than now.
Eventually the atmosphere (at a particular wavelength) becomes opaque; no infrared photons can escape. Additional GHG has no effect beyond that point. In the real atmosphere, CO2 added by humans has to compete with much more natural CO2 and vastly more H2O. It just doesn't make any difference across most of the spectrum.
Reason #2: CO2 is not an important absorber.......
We need to remember that molecules (H2O, CO2) have resonant frequencies (wavelengths); the tri-atomic molecules,
Now look at the CO2 molecule (O-C-O). It's symmetrical and unpolarized, so it doesn't rotate when an E-M wave passes by. It has only one vibrational mode, along the O-C-O axis. It's a much less efficient absorber of E-M energy than H2O, and that's what the greenhouse effect is all about.
Because of its single (vibrational) resonance, CO2 has only a few absorption lines in Earth's infrared spectrum, around 2.5, 3.5, and 14.8 micrometers (um). What kind of infrared photons does a CO2 molecule "catch" at these wavelengths? At 14.8 um, they come from an object whose temperature is about 200 degrees K - about 100 degrees F below zero. Nothing on earth is really that cold, but everything emits radiant energy photons across the infrared spectrum. There just aren't many of them emitted at 14.8 um, and they carry very, very little energy. Capturing them does very little to keep Earth warm, like a blanket that covers only a small part of your body. Likewise, photons at 3.5 um wavelength correspond to a temperature of 828 degreees K. Terribly hot, but nothing on Earth's surface, except the inside of a volcano, or a forest fire, is like that. This is also an insignificant source of photons for the greenhouse effect.
The figure on the left illustrates the broad spectrum of absorption (top) by the H2O molecule - across the emission spectrum of the earth and lower atmosphere - in comparison with the narrow spectrum (bottom) of CO2. CO2 just doesn't catch most of the infrared energy leaving the earth - effectively, it isn't there.
Reason #3: There's very little CO2 around.......
Another reason global warming by CO2 is unimportant is because there's very little of it - 388 parts per million by volume (ppmv). That's less than 0.04 % of the atmosphere. Water vapor, on the other hand, ranges up to 4% - 100 times as much.
The real reason man-made global warming is unimportant is because natural CO2 is more than 96% of all the CO2 in the atmosphere. Even if CO2 were an important infrared absorber (as it isn't), complete elimination of all human CO2 emission would have no practical effect. Suppose we were to cut all human CO2 emission by 25% (which would cripple our economy). That would be 1% of all the CO2 in the atmosphere. Changing anything by 1% is unlikely to lead to catastrophe.
And, of course, the major emitter of CO2 is China - which is opening a new coal-fired electricity generating plant every week, and will do so for the next 15 years. They understand the science, and have no intention of restricting their CO2-based economy. India and Brazil are following the same path. But the UN - and Obama, Ritter, Udall, Bennett, Pelosi, Clinton, and our other politicians - want the US to reduce our CO2 emissions 80% by 2050. Just us. Just you. These are the politicians who just passed a "stimulus bill" - mostly pork - that will cost you, your children, and your grandchildren, trillions. A reduction of 80% in CO2 emissions means:
Incidentally, greenhouse gases lead to warming, not cooling. I hope that's obvious from the discussion above, but as "global warming" becomes less and less credible, the alarmists are beginning to claim the crisis is "climate change" - including cooling.
Another major agent of climate change - much more important than CO2 - is cloud cover. We all have experience of that; we know how a cloudy sky cools a hot Summer day, and how clouds warm a Winter night. In radiative terms, clouds are black bodies - objects which absorb all the infrared photons they receive. This is true across the IR spectrum; they're much better than gaseous H2O and CO2 in their "greenhouse effect." In daylight, they scatter sunlight back, away from Earth. So what is their net effect? Cooling? Warming? Nobody knows. Whatever it is, it's more important than CO2, and it's not controllable by humanity. Another fatal flaw in controlling the "climate crisis."
Did you get all that?
Those are the qualitative explanations of the unimportant greenhouse warming due to CO2. Let's now look at some numbers describing the magnitude of CO2's greenhouse effect. The numbers come from the IPCC's Fourth Assessment Report, Working Group 1. This document can be downloaded from the University Corporation for Atmospheric Research, at
Working Group 1 Working Group 1 contains the scientific rationale and data on which other parts of the IPCC report are based.
In AR4WG1_Pubs_FAQs, FAQ 1.1, Figure 1, you'll find a diagram of the solar energy that warms our planet's surface (168 watts/sq meter) and atmosphere (67 w/sq m), totalling 235 w/sq m. If the earth is not to warm or cool on a long term basis, that incoming solar energy must be balanced by outgoing energy in the longwave infrared (5 - 15 micrometers) spectrum. As may be seen on the right in the diagram, 235 w/sq m eventually escapes.
Of particular interest are the two energy exchanges in the lower right of the figure, 390 w/sq m radiated (up) from the surface, and 324 w/sq m radiated down from the atmosphere. This 324 w/sq m is the "greenhouse effect"; it's the radiant energy the atmosphere captures and returns to the surface, like a second sun in the sky. Fortunately, this "sun" shines even during the night. The greenhouse radiant energy warms the earth by about 33 degrees C, or 60 F. Without it, the earth would be uninhabitable. How much of this beneficial greenhouse effect is due to water vapor, and how much is due to carbon dioxide? A later table in the IPCC report tells us (though they try to hide the values).
In AR4WG1_Pubs_FAQs, you'll find FAQ 2.1, figure 2. This figure itemizes the anthropogenic greenhouse gasses
In case you're wondering how many degrees C or F these "radiative forcings" amount to, the 324 w/sq m from the atmosphere warms the earth by 33 C, so it's about a 10:1 ratio (9.81818...) of w/sq m to degrees C. So the 1.6 w/sq m of radiative forcing due to all man-made greenhouse gasses causes a warming of 0.16 C or 0.29 F.
Yes, that's what this "global warming crisis" is all about. All the carbon dioxide and other industrial greenhouse gasses added to the atmosphere have warmed the earth by a third of a Fahrenheit degree.
Incidentally, the cartoon above, of incoming and outgoing energy, is by Dr. Kevin Trenberth of NCAR; it was done for an IPCC report. Dr. Trenberth is quoted in the "ClimateGate" emails as saying:
"We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!" The numbers you see in the figure, according to Trenberth - don't work out. But that's the basis of the claims of a crisis of climate, due to CO2.
So if CO2 doesn't control Earth's climate, what does? In the long term (tens of thousands of years), it's our current location of continents, resulting from Continental Drift. In the short term (decades and centuries), it's solar and ocean variability.
Man, you wimpy Americans are nothing like us Norsemen. I'm kind of ashamed of you - since, in a sense, I depending on their geometry, may absorb infrared radiant energy by vibrating and by rotating. Take a look at the sketch on the right, a representation of the two major greenhouse gasses, H2O and CO2. Notice H2O is asymmetrical, and slightly polarized. That is, the hydrogen (H) end of the molecule tends to be slightly positive, and the oxygen (O) end slightly negative. An electromagnetic (E-M) wave, alternating between positive and negative, causes the H2O molecule to rotate, and absorb anergy. In addition, electromagnetic waves of a resonant frequency cause the H-O bonds to resonate, to vibrate. Both vibration and rotation absorb energy from the E-M wave.
that contribute to global warming. The total radiative forcing from carbon dioxide and all other anthropogenic gasses is only 1.6 watts/ square meter. That's out of the total of 324 w/sq m due to the total greenhouse effect. The rest - i.e., 322 w/sq m - comes from natural greenhouse gasses, which don't appear on Figure 2. If they did, any casual reader would immediately recognize how natural water vapor and natural carbon dioxide dominate the greenhouse effect.
was the First American. We Norse found this continent a thousand years ago. Now you're letting Socialist politicians - like the ones I left behind in Europe - take it away from you. Lucky Leif
Home
Rev. Mar 2009