The thrust of what I and the “Slayers” are saying could be summarized as follows …
We don’t have to wait for the climate in the next few years to tell us who’s right and who’s wrong. Physics all along has been telling us. The warmists just don’t understand physics.
The most glaring mistake they make is in saying the atmosphere has warmed the surface (like a blanket) from -18C to +15C. The first figure is a theoretical temperature (call it small t) which is only related to the intensity of radiation via the S-B law which only relates to perfect blackbodies. Such blackbodies are usually other bodies in space which are perfectly insulated by space so there is no heat loss by conduction. In contrast the Earth’s surface is continually losing heat to the first millimetre of the atmosphere by diffusion (see Wikipedia “Heat Transfer” second paragraph) and also into the depths of the Earth’s crust or the oceans. So there is less energy left to radiate.
The actual temperature (call it capital T) is a totally different entity without direction for a start. So you cannot just subtract and get T – t = 33 deg.C, because t is not a real temperature. Without carbon dioxide and its colleagues, thermal energy would still diffuse from the surface into the atmosphere, greatly reducing the radiation, as it does. In fact the net radiation from the surface is probably less than 25 W/m^2, so what value of little t would that give you? Very cold I assure you.
This is why an IR thermometer cannot calculate temperature by measuring the intensity of the radiation and using S-B law. It can only do so by measuring the frequency and using Wien’s Displacement Law which says absolute temperature is proportional to the peak frequency.
So, given the major fallacy in the warmists “science” when they calculated and widely promulgated that 33 degree “difference” between apples and oranges, what confidence could we possibly have in any other deductions of theirs? They are also wrong in assuming radiation from a cold atmosphere can warm an already much warmer surface.
The atmosphere cools the Earth by reducing the amount of incident solar radiation which gets through. Hop out of a spacecraft and see how hot you feel in the sun’s rays. But radiation “temperature” is a very different thing from ambient temperature, both in space and, for example, at the top of a high mountain where the Sun’s rays might feel like 40C but the actual temperature of the air might be -15C.
It is important to remember that a measure of radiation is a measure of energy (Watts) transferred through a unit cross section (one square metre) and it is thus a vector with both magnitude and direction, nothing like a temperature. The only “connection” with temperature can be made if a true blackbody is emitting it, and that body is not also losing thermal energy by conduction, diffusion, convection, evaporation or any other means. If it does lose energy in such ways then, at the very least, you would need much more information before making any inferences about its temperature.
Yes, the whole Earth plus atmosphere system looks like a blackbody from outer space and some average radiating temperature could be calculated by remembering that it is a spinning sphere, not a flat disk as warmists treat it as being. But whatever temperature is calculated is merely an average temperature somewhere in the atmosphere.