There's a lot more to it than absorbing radiation
There was a very peculiar way of explaining global warming developed early on. It wasn't derived out of credible science; it came out of a need to rationalize. Strangely, it was too easy for inept scientists to convince themselves that global warming was occurring, and they needed an explanation. So they contrived an incredible logic and convinced themselves that it was true. Here's how the rationalization goes:
Some molecules absorb radiation more strongly than others. This was determined in organic chemistry, where infrared radiation is passed through molecules to identify them. When scientists did this with carbon dioxide around 1850 and found that it absorbs easily, some scientists assumed this must be occurring in the atmosphere and heating the atmosphere.
There is a saying that the first impression is the last. It's only true for persons who refuse to learn. The learning process adds to and modifies what a person already knows. Some persons are less inclined to add to and modify their knowledge than others, and they should not be scientists. Too many of them are. Instead of noticing that there are a lot of things wrong with global warming assumptions, they concocted absurd rationalizations for it.
Absorption as Trapping
The first error was to assume that absorption of radiation by carbon dioxide in the air was a process of trapping heat. All matter absorbs infrared radiation. Not realizing this contributed to the first error in assuming heat gets trapped in the atmosphere.
A jar of pickles on a kitchen table absorbs radiation. Does it trap heat? Not hardly. It emits radiation at the same rate it absorbs it.
Physicists say, emissivity equals absorptivity. It means matter emits and absorbs infrared radiation at the same rate. They also say that it doesn't matter what the chemistry of the material is, only its temperature matters. They aren't entirely correct; in fact they make adjustments for such things as the nature of the surface of solids, and there is much evidence that they got the graph wrong for the relationship between temperature and absorption, called the Stefan-Boltzmann constant. But the rationalizers of global warming missed this whole subject in assuming heat gets trapped when it is absorbed by carbon dioxide in the atmosphere.
The 33°C propaganda
The next fact that they missed was even more preposterous. They assumed that there is no other way that heat gets into the atmosphere. Could anyone miss the fact that wind sweeping over any surface carries heat away through conduction and convection? The rationalizes of global warming missed it.
Rationalizers created a mathematical formula for eliminating all methods of heat entering the atmosphere other than radiation. They applied the Stefan-Boltzmann constant, which they missed earlier, for this math. They used this constant to determine the temperature that would be required to absorb and emit the amount of radiation that the sun adds to the surface of the earth (235 watts per square meter).
The Stefan-Boltzmann constant says that an object at -18°C emits 235 W/m² of radiation. But the average temperature of the earth's surface is 15°C. So the earth's surface is 33°C warmer than it would be without an atmosphere.
That part is no concern when ignoring errors in the Stefan-Boltzmann constant. But then someone said only greenhouse gases in the atmosphere are responsible for this temperature increase of 33°C. The claim misses the conduction, convection and evaporation adding heat to the atmosphere.
Nonscientists promote this bit of absurdity claiming greenhouse gases heated the atmosphere by 33°C. State and local governments often have web sites on global warming which show this number at the top, getting their information from the federal bureaucrats who prescribe this method of proceeding. This number seems to lock in the science for nonscientists. Perhaps it's what they mean by settled science and flat earthers.
The absurdity is compounded claiming that nothing but greenhouse gases heat the atmosphere, and without greenhouse gases, the planet would be icy cold. The warm air is supposedly proof that greenhouse gases exist and trap heat in the atmosphere. If anyone actually believes such malarkey, then those of us who don't must believe the earth is flat. That set of assumptions seems to be quite common in the self-righteousness of attacking with vehemence anyone who doesn't "believe" in global warming.
Other methods show 1°C
Elsewhere, climatologists decided that humans increased the near-surface temperature by 1°C, when they increased the amount of CO2 in the air from 280 parts per million (ppm) to 380 ppm. That amount wasn't enough to rattle the journalists, so climatologists tripled it to 3°C and said the additional amount was due to secondary effects caused mostly by water vapor. Supposedly, the first 1°C of temperature increase caused more water to evaporate, and water vapor is a stronger greenhouse gas that CO2.
There is way too much difference in scale in the different methods of calculating. If humans doubling the CO2 only increases the temperature by a few degrees, how did the first 33°C occur with nature adding little more than half as much CO2 as exists now? No explanation. These are not definable, scientific concepts. The discrepancies are never looked at or explained.
Apparently, someone noticed the error in the claim that nothing but greenhouse gases add heat to the atmosphere, as this claim was removed from some web sites, but not all.
Was anyone in science really stupid enough to believe the 33°C claim, or was it just a temporary gimmick for getting the ball rolling, which is no longer needed? Either way, it's a major indication of there being no real science to the subject.
What is a stronger greenhouse gas?
Another absurdity is trying to figure out what in the H a stronger greenhouse gas is. Ignoring the fact that there is no such thing as a greenhouse gas, what is someone trying to say about stronger greenhouse gases? There is no science to be applied to the question.
Apparently, the claim starts with a measurement in an infrared spectrophotometer, where some so-called greenhouse gases absorb all radiation at lower concentrations. Such gases absorb the small amount of radiation available to them in a short distance. Shortening the distance is not increasing the heat.
Saturation was disappeared
Absorbing all available radiation is called saturation. Saturation was recognized about a century ago, and it was a good reason to discredit the whole subject. After saturation, adding more greenhouse gas does nothing more beyond shortening the distance required to absorb all available radiation. Shortening the distance is not increasing the heat.
The concept of saturation was not enough of a reason to ignore the subject by alarmist scientists. So they found methods of going around the subject of saturation. They contrived a method of calculation through "radiative transfer equations" which gets a result in spite of saturation. Did they reduce saturation to a trivial effect? It can't be reduced that much. They have never explained how saturation disappeared in the analysis of radiative transfer equations.
Saturation was mentioned in early versions of the IPCC reports, but it disappeared several reports back with no further mention. Here's how it was described in the IPCC report, AR3, 2001: "Carbon dioxide absorbs infrared radiation in the middle of its 15 mm [sic] band to the extent that radiation in the middle of this band cannot escape unimpeded: this absorption is saturated. This, however, is not the case for the band’s wings. It is because of these effects of partial saturation..."
They are saying that the edge of the absorption curve allows some radiation to be absorbed and some to go through and into space, so adding CO2 to the atmosphere allows more radiation to be absorbed. The problem is the infinitesimal amount is so absurd that no further mention of it has existed since 2001.
To understand how absurd the concept is for absorption along the edge of the curve, called shoulders, not wings (Apparently the term wings, along with misrepresenting microns as millimeters is supposed to mean that a nonscientist wrote it up and thereby washed the hands of scientists, as futile as that logic is.) it's necessary to know how saturated CO2 is. This amount is represented by the distance which radiation must travel to be completely absorbed. No official measurement can be found for this, but a German scientist, Heinz Hug, did such a measurement, which only takes a few minutes in a laboratory, and said the distance for complete absorption is 10 meters for carbon dioxide under near-surface atmospheric conditions. He said others have indicated similar results.
This means it is zilch. There are no "wings" that are going to salvage non-saturation under such conditions. If the "wings" contained one thousandth of the CO2 molecules, saturation would still occur in ten kilometers, which means inside the earth's atmosphere. One thousandth of the heating due to CO2 is not relevant.
Of course, Heinz Hug could not publish such critical information scientifically, so he put it on the internet. No significant criticism of global warming is allowed in science or mainstream journalism. Scientists who are the least bit critical lose their ability to get grants or publish. Judith Curry is the most recent example. She was chairman of the earth science department at Georgia Tech, until she lost her ability to publish due to not enough diligence in attacking critics of global warming. She wasn't a direct critic herself, just not critical enough of those who are. This is why you get this criticism from an independent scientist or not at all.
Why there is no such thing as a greenhouse gas
The reason why there is no such thing as a greenhouse gas is because absorbed radiation is re-emitted in about 83 femto seconds. Heating for 83 femto seconds is not heating. One wave of radiation being absorbed has about the same energy as one wave being emitted. A wave is absorbed and emitted in 83 femto seconds at an average infrared wavelength of 25 microns. An emission is actually stronger, because it includes the entire infrared band of frequencies, while absorption by carbon dioxide only includes 8% of the infrared frequencies.
Of course, absorption and re-emission is some heat regardless of how little. Does a small amount add up? If the heat is "trapped," it is adding up. But there is no such thing as trapping heat in the atmosphere. The term "heat trapping gas" was contrived for propaganda purposes. Look how hard it is to trap heat in a thermos bottle for keeping coffee warm. A reflective surface is used, sometimes a vacuum and two layers of insulating material. None of those insulating methods exist in the atmosphere. In fact, radiation leaves uninhibitedly from all points in a transparent gas.
This is why the atmosphere gets cold fast when going up to higher elevations. It's because radiation leaves so fast from the transparent atmosphere that heat can only be significant near the surface, where it gets added rapidly through conduction and convection. Even if greenhouse gases were relevant, 15-30% of the infrared radiation goes around greenhouse gases and cools the atmosphere. The rest of the radiation goes through greenhouse gases almost as fast by being re-emitted.
This raises the question of how strong is the radiation compared to the conduction, convection and evaporation. Radiation is very weak by comparison. Evidence indicates that 1-3% of the heat leaving the surface of the earth is in the form of radiation.
The weakness of radiation is highly visible when working with electronics, where heat build-up is always a concern. Cooling devices must have a lot of surface area, often requiring metal fins, and when a fan is used, cooling increases by a factor of 40 or more. There is always some air movement on the surface of the earth, which is like a strong fan doing the cooling.
But physicists say 79% of the energy leaving the surface of the earth is in the form of radiation. White hot metals could not emit 79% radiation under atmospheric conditions. A vacuum environment would be required to get 79% radiation from white hot metals.
The claim of 79% radiation was so ridiculous that the NASA lab tried to improve it somewhat by showing 41% radiation with their energy budget. After a few years, they reconstructed their energy budget to show 79%. The reason is because when applying the Stefan-Boltzmann constant, something close to 79% is required. That's because the Stefan-Boltzmann constant is in error and shows 20-50 times too much radiation at normal temperatures. So the IPCC reports state the number to be 79%, and NASA had to conform to that number in spite of its total ridiculousness.
When climatologists have to stick with such an absurd number, how reliable are they? Propaganda is more important to them than real science.
Trapping cannot occur as heat build-up
The absurd amount of radiation doesn't salvage the global warming concept. However easy radiation is emitted from the opaque surface of the earth, it will be emitted much easier from the transparent gas of the atmosphere. In other words, the energy leaves the atmosphere much easier than it gets in. Radiation can leave from every point in a transparent gas, top to bottom, but only from the surface of an opaque solid.
This means the concept of global warming by greenhouse gases is dependent upon heat build-up resulting from the 83 femto seconds that is required for it to be re-emitted after absorption. There is no such thing as heat build-up for so-called greenhouse gases, because radiation leaves easier than it is absorbed.
In fact, each molecule of a gas in the atmosphere will bump into its surrounding molecules while emitting radiation. This bumping (conduction) spreads the energy to about five molecules. This is not a heat build-up, because each of those five molecules is also radiating. The heat will radiate faster from five molecules than one. It means absorption into one molecule is emitted from five molecules in a little more than 83 femto seconds.
Whatever it does, it's diluted by a factor of 2,500
Is heat spreading into five molecules for each molecule of a greenhouse gas the cause of global warming? Each carbon dioxide molecule in the atmosphere is surrounded by 2,500 air molecules at 400 parts per million CO2. However much heat is added to those five molecules, it is diluted by the other 2,500 molecules. If the five molecules increase in temperature a billionth of a degree, the net air temperature increase would be 0.4 trillionths of a degree, which is about what global warming by greenhouse gases consists of. It doesn't build up to more than that, because there is no such thing as trapping heat in the atmosphere.
To claim that the atmosphere is heated 1°C through this process, is to say the temperature of each CO2 molecule increases 2,500°C, because the heat must be spread over that many additional molecules.
Physicists admit that the temperature of the CO2 molecules cannot be much different than the rest of the air temperature. Therefore, to get significant temperature increase would require a trapping effect to build up the heat over time. There is no such trapping effect, and no scientist has ever described one. The contradictions go unaccounted for, and they are endless.