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Posted at 12:45 PM ET, 11/12/2010

Discovery of the greenhouse effect: a short history

By Steve Tracton

* Rain early next week? Full Forecast | November 11, 1987 memories *

greenhouse.jpg
Diagram of the greenhouse effect. Source: EPA

Whether you are a die-hard denier of anthropogenic global warming, believe unequivocally in catastrophic human-caused global warming, or lie skeptically somewhere between these "wing nuts", there is (at least) one critically relevant common denominator: the greenhouse effect.

Yet, I'll bet wherever you stand on the subject of global warming a vast majority believe the greenhouse effect is an invention of the 20th century. Not so!

The first science (physics) based possibility of what is now known as the greenhouse effect was proposed by Joseph Fourier in 1824. Fourier calculated the earth would be an average of about 60 degrees Fahrenheit cooler if it was warmed only by incoming (short-wave) solar radiation. He concluded the atmosphere must act as an insulator of heat loss by the outgoing (long-wave) radiation emitted by the earth's surface. However, Fourier did not speculate on what gases in the atmosphere were responsible for trapping the heat.

That question was not addressed until 1859 when John Tyndall began to study the capacities of various gases to intercept and absorb the heat radiated toward space. The general view of physicists at this time for seemingly inexplicable reasons was that atmospheric gases were effectively transparent to radiant heat leaving the earth's surface or absorbed imperceptible amounts.

Tyndall constructed an apparatus to measure the capacity of the individual gaseous constituents of the atmosphere to absorb or transmit heat. He showed that the main atmospheric gases, nitrogen and oxygen, are almost transparent to radiant heat. The most important discovery was that carbon dioxide and water vapor were strong absorbers of radiant energy and that even in relatively small quantities they could account for the heat trapped by the atmosphere. Indeed, New Scientist referred to Tyndall as the "man who discovered greenhouse gases".

Moreover, Tyndall was convinced that changes in the various components of the atmosphere could have produced "all the mutations of climate which the researches of geologists reveal". He could not possibly have imagined that this very subject 150 years later would become the science and political hot potato at the center of the intense discussion (debate) on global warming and climate change.

Note: An organization was established in 2000 based in the United Kingdom to bring together scientists, economists, engineers and social scientists to the issues surrounding climate change. In recognition of John Tyndall's contributions, it is known as Tyndall Centre for Climate Change Research.

By Steve Tracton  | November 12, 2010; 12:45 PM ET
Categories:  Climate Change, Tracton  
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Comments

Tyndall is perhaps best known for what is now known as the "Tyndall effect", the visible scattering of light caused by small particles in a colloidal suspension.

Smog is a good example of a gaseous colloid. The particles of fog and smoke [airborne particulates]remain suspended and are visible to the eye. Particles in a true solution are too small to be visible to the eye. Pure air is basically a solution of oxygen plus small amounts of each inert gas [argon, neon, krypton, etc.] in nitrogen and is a true mixture, chemically speaking.

Posted by: Bombo47jea | November 12, 2010 1:11 PM | Report abuse

I think you need to switch long and short in the third paragraph, incoming short wave and outgoing long wave.

Posted by: eric654 | November 12, 2010 2:48 PM | Report abuse

@eric654

You're right. Fixed.

Posted by: Jason-CapitalWeatherGang | November 12, 2010 2:58 PM | Report abuse

Water vapor is the most meterologically significant gaseous component of the atmosphere. Based on this premise, I did a paper in grad school which concluded that for many purposes the atmosphere could be viewed as simply dilute water vapor.

Posted by: SteveT-CapitalWeatherGang | November 12, 2010 3:18 PM | Report abuse

Thanks. The EPA diagram is a little simplistic, leaves out an important step. The outgoing LW is absorbed by the CO2, but before it can be re-emitted be that same CO2 molecule the molecule bumps into an O2 or N2 molecule and warms it. Once all the gases of the atmosphere are warmed that way, the warm CO2 molecules radiate LW in all directions as stated at a rate proportional to their warmth.

Posted by: eric654 | November 12, 2010 3:28 PM | Report abuse

You can substitute "CO2 or H20 or other GHG" for "CO2" above.

Posted by: eric654 | November 12, 2010 3:30 PM | Report abuse

You forgot part of the Greenhouse Effect.
Namely that it required that an IR energy photon (radiated by the warm ground temperature) MUST be available for the Greenhouse effect to work to accomplish warming.
ON Earth there is an excess of greenhouse gases above the number of energy photons. The GHE STOPS because the photons are all in use, but there are excess GHGs still available. This is why the ocean or GHG Water Vapor exists and is not all vaporized when it absorbs the photon. This is what limits the GHE warming This is why at night when the number of energy photons decreases it cools in spite of man producing more CO2 from his heating /electricity plants.

What this means is that more GHGs does NOT means more warming. When the models say that there is Water Vapor feedback they assume that Adding CO2 first causes more warming, and teh warming ccuses more water vapor and teis causes even more GHE feedback. BUT if all the photons are in use, the added CO2 & added Water vapor will not cause feedback waarming. Arrhenius in 1896 however said that more GHGs does cause more warming. The IPCC and current computer models also adopted this erroneous Arrhenius conclusion, and wrote it into the computer models. This is why all the computer models always produce warming, and do not allow the models to produce cooling, even though it is obvious that cooling happens.
In summary the so called science that justiies the very real observed global warming is flawed.
The real story is that there is a variable cyclic insrease ans decrease in teh ground temperature and teh avaiable number of energy photons to cause warminf. An alternate theory of hoe gravity and planetary eccentricity cause energy to move from heat or kinetic energy to gravitational potential energy as the Earth gets further away from the sources of gravity- ie the sun and the planets- primarily Jupiter. It then returns to heat as the Earth gets closer to the planets as their orbits get closer. This is discussed in the paper "Gravity causes Climate Change" available in www.scribd.com. The IPCC climate models do not address gravity or potential energy.

Posted by: JDoddsGW | November 12, 2010 9:12 PM | Report abuse

JDoddsGW, there are a number of notions in your post that are incorrect. First, there are IR photons passing through the atmosphere without being absorbed by any clouds or gases. They are shown in the IR satellite pictures, e.g. http://www.goes.noaa.gov/ECIR4.html Note that the images display the warmest objects in black and the coldest in white. So cold, high clouds are white and the warm ground is dark and the warmer ocean is darker.

Second, increases in CO2 cause increases in warming as shown in simple experiments by Dr. Spencer (a CAGW skeptic); http://www.drroyspencer.com/2010/08/help-back-radiation-has-invaded-my-backyard/ He shows, for example, that the back radiation from CO2 decreases as he gained elevation (since there was less CO2 above him to radiate down to him). This was despite the fact that the ambient temperature was the same at the bottom and top of the hill.

Third, while gravitational potential energy is real (i.e. an object further from Jupiter has more potential energy than closer), it is not clear how the change in potential is converted to heat in quantities comparable to the energy from CO2 back radiation. From CO2 we are talking about 10^18 Joules per second for back radiation from CO2 for the planet. For Jupiter varying in distance by 300,000,000 km from earth, the g.p.e. is 10^23 Joules over a year (G is 10^-11, atmosphere is 5 × 10^18 kg, Jupiter is 1.8986×10^27 kg) But CO2 is about 10*25 Joules per year of direct heat.

That's versus at least 100x less in potential energy, not heat. It is not clear how that gets converted to heat. For example, the ocean tides caused by the moon contain far more energy but are a small part of the earth's energy budget.

Posted by: eric654 | November 12, 2010 11:22 PM | Report abuse

Eric654
Thanks for responding . This is the first scientific response I've had. Would appreciate talking scientifically offline if you have the time. Email: JDoddsGW@sbcglobal.net

Responses:
1.Yes there are IR windows in the spectrum and we do get direct to space radiation. Trenberth says it is less that a few percent of the total. BUT the spectra for CO2& water vapor absorbtion show 100% absorbtion. ie there is excess CO2 & WV in the air so adding more GHG does NOT result in more absorbtion at the absorbtion frequency. hence no added warming by GHG addition. HOWEVER you will get more warming if you add more photons (sun rising every morning)
2. Dr Spenser's back radiation: First the Trenberth Energy BAlance diagram is incorrect. First it is at a transient condition not equilibrium. At equilibrium in equals out. The NET energy in from the sun equals the energy out to space. The back radiation number reflect the situation of a single bounce at the ground. IN reality the ground radiates, it is absorbed, half goes up& out half goes down (as backradiation) which then MUST also bounce at the ground to go up as "rebounced radiation?". & join the incoming Sun's radiation, After 6-8 ground bounces we are at equilibrium (microseconds)Then suns total energy in equals the energy out to space. The back radiation number exactly cancels the the return of the back radiation to space from the ground. ie they cancel vectorwise. & we are left with equilibrium energy from sun (converted to IR) equals NET energy to space.

The exact same scenario occurs in an electrical wire conducting electrons (ie electricity) When an electon goes down the wire it hits an atom. Half bounces forward, half backward. at equilibrium you still get energy in equals out & we get electricity based on the power in= out (less inefficiency losses of course)
In both cases there IS back radiation which on a vector basis gets cancelled out. My explanation is that we MUST account for the vectors of the energy flow- and use the NET flows. ??? )
3.Gravity:
I do not know how PE gets converted to KE & temp- my best explanation is friction. But try explaining a pendulum. PE goes to KE as velocity with no apparent mechanism. If you stop a pendulum at the bottom you WILL get friction heat when it hits the wall.
MAgnitude: What your math is implying is that sunlight is greater than gravity changes. So why can gravity move the Earth 300,000,000 KM in eccentricity, but sunlight shining on Earth can not budge it? My intuitive explanation is that gravity is WAY bigger than sun light. Sunlight can only push the Earth in its orbit out. Gravity counters that by bringing the Earth back into the eccentric orbit closer to the sun. Also in your calcs (I assume its correct) you only considered Jupiter. What about the SUN, & other planets ?Sun & moon's gravity (1yr)effects are much greater than Jupiter-12 yr orbit. BUT changes in Jupiter effects are greater than sun's changes. Need more space

Posted by: JDoddsGW | November 19, 2010 2:01 PM | Report abuse

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